Figure 3. Computed contour of velocity magnitude (m/s) for Run 1 to Run 15.

FLOW-3D 소프트웨어를 이용한 유입구 및 배플 위치가 침전조 제거 효율에 미치는 영향

Ali Poorkarimi1
Khaled Mafakheri2
Shahrzad Maleki2

Journal of Hydraulic Structures
J. Hydraul. Struct., 2023; 9(4): 76-87
DOI: 10.22055/jhs.2024.44817.1265

Abstract

중력에 의한 침전은 부유 물질을 제거하기 위해 물과 폐수 처리 공정에 널리 적용됩니다. 이 연구에서는 침전조의 제거 효율에 대한 입구 및 배플 위치의 영향을 간략하게 설명합니다. 실험은 CCD(중심복합설계) 방법론을 기반으로 수행되었습니다. 전산유체역학(CFD)은 유압 설계, 미래 발전소에 대한 계획 연구, 토목 유지 관리 및 공급 효율성과 관련된 복잡한 문제를 모델링하고 분석하는 데 광범위하게 사용됩니다. 본 연구에서는 입구 높이, 입구로부터 배플까지의 거리, 배플 높이의 다양한 조건에 따른 영향을 조사하였다. CCD 접근 방식을 사용하여 얻은 데이터를 분석하면 축소된 2차 모델이 R2 = 0.77의 결정 계수로 부유 물질 제거를 예측할 수 있음이 나타났습니다. 연구 결과, 유입구와 배플의 부적절한 위치는 침전조의 효율에 부정적인 영향을 미칠 수 있음을 보여주었습니다. 입구 높이, 배플 거리, 배플 높이의 최적 값은 각각 0.87m, 0.77m, 0.56m였으며 제거 효율은 80.6%였습니다.

Sedimentation due to gravitation is applied widely in water and wastewater treatment processes to remove suspended solids. This study outlines the effect of the inlet and baffle position on the removal efficiency of sedimentation tanks. Experiments were carried out based on the central composite design (CCD) methodology. Computational fluid dynamics (CFD) is used extensively to model and analyze complex issues related to hydraulic design, planning studies for future generating stations, civil maintenance, and supply efficiency. In this study, the effect of different conditions of inlet elevation, baffle’s distance from the inlet, and baffle height were investigated. Analysis of the obtained data with a CCD approach illustrated that the reduced quadratic model can predict the suspended solids removal with a coefficient of determination of R2 = 0.77. The results showed that the inappropriate position of the inlet and the baffle can have a negative effect on the efficiency of the sedimentation tank. The optimal values of inlet elevation, baffle distance, and baffle height were 0.87 m, 0.77 m, and 0.56 m respectively with 80.6% removal efficiency.

Keywords

Sedimentation tank, Particle removal, Central Composite Design, Computational
Fluid Dynamics, Flow-3D

Figure 3. Computed contour of velocity magnitude (m/s) for Run 1 to Run 15.
Figure 3. Computed contour of velocity magnitude (m/s) for Run 1 to Run 15.

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Figure 1 | Schematic of the present research model with dimensions and macro-roughnesses installed.

On the hydraulic performance of the inclined drops: the effect of downstreammacro-roughness elements

경사 낙하의 수력학적 성능: 하류 거시 거칠기 요소의 영향

Farhoud Kalateh a,*, Ehsan Aminvash a and Rasoul Daneshfaraz b
a Faculty of Civil Engineering, University of Tabriz, Tabriz, Iran
b Faculty of Engineering, University of Maragheh, Maragheh, Iran
*Corresponding author. E-mail: f.kalateh@gmail.com

ABSTRACT

The main goal of the present study is to investigate the effects of macro-roughnesses downstream of the inclined drop through numerical models. Due to the vital importance of geometrical properties of the macro-roughnesses in the hydraulic performance and efficient energy dissipation downstream of inclined drops, two different geometries of macro-roughnesses, i.e., semi-circular and triangular geometries, have been investigated using the Flow-3D model. Numerical simulation showed that with the flow rate increase and relative critical depth, the flow energy consumption has decreased. Also, relative energy dissipation increases with the increase in height and slope angle, so that this amount of increase in energy loss compared to the smooth bed in semi-circular and triangular elements is 86.39 and 76.80%, respectively, in the inclined drop with a height of 15 cm and 86.99 and 65.78% in the drop with a height of 20 cm. The Froude number downstream on the uneven bed has been dramatically reduced, so this amount of reduction has been approximately 47 and 54% compared to the control condition. The relative depth of the downstream has also increased due to the turbulence of the flow on the uneven bed with the increase in the flow rate.

본 연구의 주요 목표는 수치 모델을 통해 경사 낙하 하류의 거시 거칠기 효과를 조사하는 것입니다. 수력학적 성능과 경사 낙하 하류의 효율적인 에너지 소산에서 거시 거칠기의 기하학적 특성이 매우 중요하기 때문에 두 가지 서로 다른 거시 거칠기 형상, 즉 반원형 및 삼각형 형상이 Flow를 사용하여 조사되었습니다.

3D 모델 수치 시뮬레이션을 통해 유량이 증가하고 상대 임계 깊이가 증가함에 따라 유동 에너지 소비가 감소하는 것으로 나타났습니다. 또한, 높이와 경사각이 증가함에 따라 상대적인 에너지 소산도 증가하는데, 반원형 요소와 삼각형 요소에서 평활층에 비해 에너지 손실의 증가량은 경사낙하에서 각각 86.39%와 76.80%입니다.

높이 15cm, 높이 20cm의 드롭에서 86.99%, 65.78%입니다. 고르지 못한 베드 하류의 프루드 수가 극적으로 감소하여 이 감소량은 대조 조건에 비해 약 47%와 54%였습니다. 유속이 증가함에 따라 고르지 못한 층에서의 흐름의 난류로 인해 하류의 상대적 깊이도 증가했습니다.

Key words

flow energy dissipation, Froude number, inclined drop, numerical simulation

Figure 1 | Schematic of the present research model with dimensions and macro-roughnesses installed.
Figure 1 | Schematic of the present research model with dimensions and macro-roughnesses installed.
Figure 2 | Meshing, boundary condition, and solution field network
Figure 2 | Meshing, boundary condition, and solution field network

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Figure 4. Rectangular stepped spillway with (a) three baffle arrangement (b) five baffle arrangement

Prediction of Energy Dissipation over Stepped Spillwaywith Baffles Using Machine Learning Techniques

Saurabh Pujari*
, Vijay Kaushik, S. Anbu Kumar
Department of Civil Engineering, Delhi Technological University, India
Received February 23, 2023; Revised April 25, 2023; Accepted June 11, 2023
Cite This Paper in the Following Citation Styles
(a): [1] Saurabh Pujari, Vijay Kaushik, S. Anbu Kumar , “Prediction of Energy Dissipation over Stepped Spillway with
Baffles Using Machine Learning Techniques,” Civil Engineering and Architecture, Vol. 11, No. 5, pp. 2377 – 2391, 2023.
DOI: 10.13189/cea.2023.110510.
(b): Saurabh Pujari, Vijay Kaushik, S. Anbu Kumar (2023). Prediction of Energy Dissipation over Stepped Spillway with
Baffles Using Machine Learning Techniques. Civil Engineering and Architecture, 11(5), 2377 – 2391. DOI:
10.13189/cea.2023.110510.
Copyright©2023 by authors, all rights reserved. Authors agree that this article remains permanently open access under
the terms of the Creative Commons Attribution License 4.0 International License

Abstract

In river engineering, the stepped spillway of a dam is an important component that may be used in various ways. It is necessary to conduct research dealing with flood control in order to investigate the method, in which energy is lost along the tiered spillways. In the past, several research projects on stepped spillways without baffles have been carried out utilizing a range of research approaches. In the present study, machine learning techniques such as Support Vector Machine (SVM) and Regression Tree (RT) are used to analyze the energy dissipation on rectangular stepped spillways that make use of baffles in a variety of configurations and at a range of channel slopes. The results of many experiments indicate that the amount of energy that is lost increases with the number of baffles that are present in flat channels with slopes and rises. In order to evaluate the efficiency and usefulness of the suggested model, the statistical indices that were developed for the experimental research are used to validate the models that were created for the study. The findings indicate that the suggested SVM model properly predicted the amount of energy that was dissipated when contrasted with RT and the method that had been developed in the past. This study verifies the use of machine learning techniques in this industry, and it is unique in that it anticipates energy dissipation along stepped spillways utilizing baffle designs. In addition, this work validates the use of machine learning methods in this field.

Keywords

Rectangular Stepped Spillways, Baffle Arrangements, Channel Slope, Support Vector Machine (SVM), Regression Tree (RT)

Introduction

To regulate water flows downstream of a dam, a spillway structure is employed, with stepped spillways preventing water from overflowing and causing damage to the dam. These spillways consist of a channel with built-in steps or drops. Flow patterns observed include nappe flow, transition flow, and skimming flow [1]. Numerous scholars have looked at the energy dissipation in stepped spillways [2-4]. Boes and Hager [5] looked at the benefits of stepped spillways, such as their simplicity of construction, less danger of cavitation, and smaller stilling basins at downstream dam toes owing to considerable energy loss along the chute. Hazzab and Chafic [7] conducted an experimental study on energy dissipation in stepped spillways and reported on flow configurations. Additionally, the Manksvill dam spillway was examined using a 1:25 scale physical wooden model [6]. For moderately inclined stepped channels, Stefan and Chanson [8] explored air-water flow measurements. Daniel [9] discussed how the existence of steps and step heights affect stepped spillways’ ability to dissipate energy. A comparison of the smooth invert chute flow with the self aerated stepped spillway. The energy dissipation in stepped spillways was investigated using various methods. Katourany [10] compared experimental findings to conventional USBR outcomes to examine the effects of different baffle widths, spacing between baffle rows, and step heights of baffled aprons. Salmasi et al. [11] assessed the energy dissipation of through-flow and over-flow in gabion stepped spillways, discovering that gabion spillways with pervious surfaces dissipated energy more efficiently than those with concrete walls. Other forms of stepped spillways, such as inclined steps and steps with end sills, were also quantitatively studied for energy dissipation [12]. Saedi and Asareh [13] examined how the number of drop stairs affected energy dissipation in stepped drops and suggested using stepped drops to increase energy dissipation by providing flow path roughness. Al-Husseini [14] found that decreasing the number of steps and downstream slopes led to an increase in flow energy dissipation, and that the use of cascade spillways reduced energy dissipation compared to the original step spillway. MARS and ANN methods were used to estimate energy dissipation in flow across stepped spillways under skimming flow conditions, with both models proving reliable [15]. Frederic et al. [16] evaluated the energy dissipation effectiveness and stability of the Mekin Dam spillway by confirming that flow did not result in transitional flow and by calculating safety factors at various intervals. A numerical model was developed to validate a physical model examining the impact of geometrical parameters on the dissipation rate in flows through stepped spillways [17]. The regulation of the rates of dissipation is studied using a particular kind of fuzzy inference system (FIS). The findings are compared with a predefined numerical database to determine the predicted energy dissipation under various circumstances. The findings show that the suggested FIS may be a useful tool for the operational management of dissipator structures while taking various geometric characteristics into account. Nasralla [18] studied the four phases of the spillway and conducted eighteen runs to enhance energy dissipation through the contraction-stepped spillway. The study considered alternative baffle placements, heights, and widths. The results showed that downstream baffles on the stepped spillway of the stilling basin improve energy dissipation. Using the Flow 3D software, Ikinciogullari [19] quantitatively analyzed the energy dissipation capabilities of trapezoidal stepped spillways using four distinct models and three different discharges. The findings showed that trapezoidal stepped spillways are up to 30% more efficient in dissipating energy than traditional stepped spillways. In previous works, only a few machine learning algorithms were used to forecast energy dissipation across a rectangular stepped spillway without baffles. Therefore, this study used machine learning approaches such as Support Vector Machine (SVM) and Regression Tree (RT) to predict energy dissipation across a rectangular stepped spillway with varied rectangular-shaped baffle configurations at different channel slopes. The study compared these models using statistical analysis to assess their efficiency in predicting energy dissipation over rectangular stepped spillways with baffles. 2. Materials and Methods 2.1. Experimental Setup The experiments were carried out at the Hydraulics laboratory of Delhi Technological University. The tests were performed in a rectangular tilting flume of 8m long, 0.30m wide and 0.40m deep which has a facility to make it horizontal and sloping as well (shown in Figure 1). The flume consists of an inlet section, an outlet section, and a collecting tank at the downstream end which is used to measure the discharge. Figure 2 depicts the model of a rectangular stepped spillway prepared using an acrylic sheet having a width of 0.30m, a height of 0.20m and a base length of 0.40m. A total of four steps were designed with a step height of 0.05m, the step length is 0.10m and rectangular-shaped baffles of length 0.10m and height of 0.05m were arranged in different manner. Figure 3 represents the different baffle arrangements used in the experimental work. At first, the experiment was conducted for no baffle condition. Thereafter the experiment was conducted for the first arrangement of three baffles, in which two baffles were placed at a distance of 0.10m from the toe of the spillway and a distance of 0.10m was maintained between the first two baffles and the third baffle was placed between the first two baffles at a distance of 0.20m from the toe of the spillway (figure 4a). After that, the experiment was conducted for the third arrangement of baffles which consists of five baffles, two more baffles were introduced at a distance of 0.30m from the toe of the spillway and a distance of 0.10m was maintained between them (figure 4b). The baffles used in the experiment were rectangular shaped which had a height of 0.05m and length of 0.10m. The experiments were conducted for five different discharges 2 l/s, 4 l/s, 6 l/s, 8 l/s and 10 l/s. For the purpose of determining the head values both upstream and downstream of the spillway model, a point gauge with a precision of 0.1mm was used. In order to determine the average velocities of the upstream and downstream portions, respectively, a pitot static tube was used in conjunction with a digital manometer.

Figure 1. Rectangular tilting flume
Figure 2. Dimensions of classical stepped spillway
Figure 3. Arrangements of baffles in classical stepped spillway
Figure 4. Rectangular stepped spillway with (a) three baffle arrangement (b) five baffle arrangement
Figure 1. Three-dimensional finite element model of local scouring of semi-exposed submarine cable.

반노출 해저케이블의 국부 정련과정 및 영향인자에 대한 수치적 연구

Numerical Study of the Local Scouring Process and Influencing Factors of Semi-Exposed Submarine Cables

by Qishun Li,Yanpeng Hao *,Peng Zhang,Haotian Tan,Wanxing Tian,Linhao Chen andLin Yang

School of Electric Power Engineering, South China University of Technology, Guangzhou 510640, China

*Author to whom correspondence should be addressed.J. Mar. Sci. Eng.202311(7), 1349; https://doi.org/10.3390/jmse11071349

Received: 10 June 2023 / Revised: 19 June 2023 / Accepted: 27 June 2023 / Published: 1 July 2023(This article belongs to the Section Ocean Engineering)

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Abstract

Local scouring might result in the spanning of submarine cables, endangering their mechanical and electrical properties. In this contribution, a three-dimensional computational fluid dynamics simulation model is developed using FLOW-3D, and the scouring process of semi-exposed submarine cables is investigated. The effects of the sediment critical Shields number, sediment density, and ocean current velocity on local scouring are discussed, and variation rules for the submarine cables’ spanning time are provided. The results indicate that three scouring holes are formed around the submarine cables. The location of the bottom of the holes corresponds to that of the maximum shear velocity. The continuous development of scouring holes at the wake position leads to the spanning of the submarine cables. The increase in the sediment’s critical Shields number and sediment density, as well as the decrease in the ocean current velocity, will extend the time for maintaining the stability of the upstream scouring hole and retard the development velocity of the wake position and downstream scouring holes. The spanning time has a cubic relationship with the sediment’s critical Shields number, a linear relationship with the sediment density, and an exponential relationship with the ocean current velocity. In this paper, the local scouring process of semi-exposed submarine cables is studied, which provides a theoretical basis for the operation and maintenance of submarine cables.

Keywords: 

submarine cablelocal scouringnumerical simulationcomputational fluid dynamics

1. Introduction

As a key piece of equipment in cross-sea power grids, submarine cables are widely used to connect autonomous power grids, supply power to islands or offshore platforms, and transmit electric power generated by marine renewable energy installations to onshore substations [1]. Once submarine cables break down due to natural disasters or human-made damage, the normal operation of other marine electric power equipment connected to them may be affected. These chain reactions will cause great economic losses and serious social impacts [2].

To protect submarine cables, they are usually buried 1 to 3 m below the seabed [3]. However, submarine cables are still confronted with potential threats from the complex subsea environment. Under the influence of fishing, anchor damage, ocean current scouring, and other factors, the sediment above submarine cables will always inevitably migrate. When a submarine cable is partially exposed, the scouring at this position will be exacerbated; eventually, it will cause the submarine cable to span. According to a field investigation of the 500 kV oil-filled submarine cable that is part of the Hainan networking system, the total length of the span is 49 m [4]. Under strong ocean currents, spanning submarine cables may experience vortex-induced vibrations. Fatigue stress caused by vortex-induced vibrations may lead to metal sheath rupture [5], which endangers the mechanical and electrical properties of submarine cables. Therefore, understanding the local scouring processes of partially exposed submarine cables is crucial for predicting scouring patterns. This is the basis for developing effective operation and maintenance strategies for submarine cables.

The mechanism and influencing factors of sediment erosion have been examined by researchers around the world. In 1988, Sumer [6] conducted experiments to show that the shedding vortex in the wake of a pipeline would increase the Shields parameter by 3–4 times, which would result in severe scouring. In 1991, Chiew [7] performed experiments to prove that the maximum scouring depth could be obtained when the pipeline was located on a flat bed and was scoured by a unidirectional water flow. Based on the test results, they provided a prediction formula for the maximum scouring depth. In 2003, Mastbergen [8] proposed a one-dimensional, steady-state numerical model of turbidity currents, which considered the negative pore pressures in the seabed. The calculated results of this model were basically consistent with the actual scouring of a submarine canyon. In 2007, Dey [9] presented a semitheoretical model for the computation of the maximum clear-water scour depth below underwater pipelines in uniform sediments under a steady flow, and the predicted scour depth in clear water satisfactorily agreed with the observed values. In 2008, Dey [10] conducted experiments on clear-water scour below underwater pipelines under a steady flow and obtained a variation pattern of the depth of the scouring hole. In 2008, Liang [11] used a two-dimensional numerical simulation to study the scouring process of a tube bundle under the action of currents and waves. They discovered that, compared with the scouring of a single tube, the scouring depth of the tube bundle was deeper, and the scouring time was longer. In 2012, Yang [12] found that placing rubber sheets under pipes can greatly accelerate their self-burial. The rubber sheets had the best performance when their length was about 1.5 times the size of the pipe. In 2020, Li [13] investigated the two-dimensional local scour beneath two submarine pipelines in tandem under wave-plus-current conditions via numerical simulation. They found that for conditions involving waves plus a low-strength current, the scour pattern beneath the two pipelines behaved like that in the pure-wave condition. Conversely, when the current had equal strength to the wave-induced flow, the scour pattern beneath the two pipelines resembled that in the pure-current condition. In 2020, Guan [14] studied and discussed the interactive coupling effects among a vibrating pipeline, flow field, and scour process through experiments, and the experimental data showed that the evolution of the scour hole had significant influences on the pipeline vibrations. In 2021, Liu [15] developed a two-dimensional finite element numerical model and researched the local scour around a vibrating pipeline. The numerical results showed that the maximum vibration amplitude of the pipeline could reach about 1.2 times diameter, and the maximum scour depth occurred on the wake side of the vibrating pipeline. In 2021, Huang [16] carried out two-dimensional numerical simulations to investigate the scour beneath a single pipeline and piggyback pipelines subjected to an oscillatory flow condition at a KC number of 11 and captured typical steady-streaming structures around the pipelines due to the oscillatory flow condition. In 2021, Cui [17] investigated the characteristics of the riverbed scour profile for a pipeline buried at different depths under the condition of riverbed sediments with different particle sizes. The results indicated that, in general, the equilibrium scour depth changed in a spoon shape with the gradual increase in the embedment ratio. In 2022, Li [18] used numerical simulation to study the influence of the burial depth of partially buried pipelines on the surrounding flow field, but they did not investigate the scour depth. In 2022, Zhu [19] performed experiments to prove that the scour hole propagation rate under a pipeline decreases with an increasing pipeline embedment ratio and rises with the KC number. In 2022, Najafzadeh [20] proposed equations for the prediction of the scouring propagation rate around pipelines due to currents based on a machine learning model, and the prediction results were consistent with the experimental data. In 2023, Ma [21] used the computational fluid dynamics coarse-grained discrete element method to simulate the scour process around a pipeline. The results showed that this method can effectively reduce the considerable need for computing resources and excessive computation time. In 2023, through numerical simulations, Hu [22] discovered that the water velocity and the pipeline diameter had a significant effect on the depth of scouring.

In the preceding works, the researchers investigated the mechanism of sediment scouring and the effect of various factors on the local scouring of submarine pipelines. However, submarine cables are buried beneath the seabed, while submarine pipelines are erected above the seabed. The difference in laying methods leads to a large discrepancy between their local scouring processes. Therefore, the conclusions of the above investigations are not applicable to the local scouring of submarine cables. Currently, there is no report on the research of the local scouring of partially exposed submarine cables.

In this paper, a three-dimensional computational fluid dynamics (CFD) finite element model, based on two-phase flow, is established using FLOW-3D. The local scouring process of semi-exposed submarine cables under steady-state ocean currents is studied, and the variation rules of the depth and the shape of the scouring holes, as well as the shear velocity with time, are obtained. By setting different critical Shields numbers of the sediment, different sediment densities, and different ocean current velocities, the change rule of the scouring holes’ development rate and the time required for the spanning of submarine cables are explored.

2. Sediment Scouring Model

In the sediment scouring model, the sediment is set as the dispersed particle, which is regarded as a kind of quasifluid. In this context, sediment scouring is considered as a two-phase flow process between the liquid phase and solid particle phase. The sediment in this process is further divided into two categories: one is suspended in the fluid, and the other is deposited on the bottom.When the local Shields number of sediment is greater than the critical Shields number, the deposited sediment will be transformed into the suspended sediment under the action of ocean currents. The calculation formulae of the local Shields numbers θ and the critical Shields numbers 

θcr of sediment is given as [23,24

]

𝜃=𝑈2𝑓(𝜌𝑠/𝜌𝑓−1)𝑔𝑑50,�=��2(��/��−1)��50,(1)

𝜃𝑐𝑟=0.31+1.2𝐷∗+0.055(1−𝑒−0.02𝐷∗),���=0.31+1.2�*+0.055(1−�−0.02�*),(2)

𝐷∗=𝑑50𝜌𝑓(𝜌𝑠−𝜌𝑓)𝑔/𝜇2−−−−−−−−−−−−−−√3,�*=�50��(��−��)�/�23,(3)where 

Uf is the shearing velocity of bed surface, 

ρs is the density of the sediment particle, 

ρf is the fluid density, g is the acceleration of gravity, d

50 is the median size of sediment, and μ is the dynamic viscosity of sediment.And each sediment particle suspended in the fluid obeys the equations for mass conservation and energy conservation

∂𝑐𝑠∂𝑡+∇⋅(𝑢𝑐𝑠)=0,∂��∂�+∇⋅(�¯��)=0,(4)

∂𝑢𝑠∂𝑡+𝑢⋅∇𝑢𝑠=−1𝜌𝑠∇𝑃+𝐹−𝐾𝑓𝑠𝜌𝑠𝑢𝑟,∂��∂�+�¯⋅∇��=−1��∇�+�−�������,(5)where 

cs is the concentration of the sediment particle, 

𝑢�¯ is the mean velocity vector of the fluid and the sediment particle, 

us is the velocity of the sediment particle, 

fs is the volume fraction of the sediment particle, P is the pressure, F is the volumetric and viscous force, K is the drag force, and 

ur is the relative velocity.

3. Numerical Setup and Modeling

In this paper, a three-dimensional submarine cable local scouring simulation model is established by FLOW-3D. Based on the numerical simulation, the process of the submarine cable, which gradually changes from semi-exposed to the spanning state under the steady-state ocean current, is studied. The geometric modeling, the mesh division, the physical field setup, and the grid independent test of CFD numerical model are as follows.

3.1. Geometric Modeling and Mesh Division

A three-dimensional (3D) numerical model of the local scouring of a semi-exposed submarine cable is established, which is shown in Figure 1. The dimensions of the model are marked in Figure 1. The inlet direction of the ocean current is defined as the upstream of the submarine cable (referred to as upstream), and the outlet direction of the ocean current is defined as the downstream of the submarine cable (referred to as downstream).

Jmse 11 01349 g001 550

Figure 1. Three-dimensional finite element model of local scouring of semi-exposed submarine cable.

The submarine cable with a diameter of 0.2 m is positioned on sediment that is initially in a semi-exposed state. When the length of the span is short, the submarine cable will not show obvious deformation due to gravity or scouring from the ocean current. Therefore, the submarine cable surface is set as the fixed boundary. The model’s left boundary is set as the inlet, the right boundary is set as the outlet, the front and rear boundaries are set as symmetry, and the bottom boundary is set as the non-slip wall. Since the water depth above the submarine cable is more than 0.6 m in practice, the top boundary of the model is also set as symmetry. The sediment near the inlet and the outlet will be carried by ocean currents, which leads to the abnormal scouring terrain. At each end of the sediment, a baffle (thickness of 3 cm) is installed to ensure that the simulation results can reflect the real situation.

Due to the fact that the flow field around the semi-exposed submarine cable is not a simple two-dimensional symmetrical distribution, it should be solved by three-dimensional numerical simulation. Considering the accuracy and efficiency of the calculation, the size of mesh is set to 0.02 m. The total number of meshes after the dissection is 133,254.

3.2. Physical Field Setup

The CFD finite element model contains four physical field modules: sediment scouring module, gravity and non-inertial reference frame module, density evaluation module, and viscosity and turbulence module. In this paper, the renormalization group (RNG) kε turbulence model is used, which has high computational accuracy for turbulent vortices. Therefore, this turbulence model is suitable for calculating the sediment scouring process around the semi-exposed submarine cable [25]. The key parameters of the numerical simulation are referring to the survey results of submarine sediments in the Korean Peninsula [26], as listed in Table 1.Table 1. Key parameters of numerical simulation.

Table

3.3. Mesh Independent Test

In order to eliminate errors caused by the quantity of grids in the calculation process, two sizes of mesh are set on the validation model, and the scour profiles under different mesh sizes are compared. The validation model is shown in Figure 2, and the scouring terrain under different mesh size is given in Figure 3.

Jmse 11 01349 g002 550

Figure 2. Validation model.

Jmse 11 01349 g003 550

Figure 3. Scouring terrain under different mesh sizes.

It can be seen from Figure 3 that with the increase in the number of meshes, the scouring terrain of the verification model changes slightly, and the scouring depth is basically unchanged. Considering the accuracy of the numerical simulation and the calculation’s time cost, it is reasonable to consider setting the mesh size to 0.02 m.

4. Results and Analysis

4.1. Analysis of Local Scouring Process

Based on the CFD finite element numerical simulation, the local scouring process of the submarine cable under the steady-state ocean current is analyzed. The end time of the simulation is 9 h, the initial time step is 0.01 s, and the fluid velocity is 0.40 m/s. Simulation results are saved every minute. Figure 4 illustrates the scouring terrain around the semi-exposed submarine cable, which has been scoured by the steady-state current for 5 h.

Jmse 11 01349 g004 550

Figure 4. Scouring terrain around semi-exposed submarine cable (scour for 5 h).

As can be seen from Figure 4, three scouring holes were separately formed in the upstream wake position and downstream of the semi-exposed submarine cable. The scouring holes are labeled according to their locations. The variation of the scouring terrain around the semi-exposed submarine cable over time is given in Figure 5. The red circle in the picture corresponds to the position of the submarine cable, and the red box in the legend marks the time when the submarine cable is spanning.

Jmse 11 01349 g005 550

Figure 5. Variation of scouring terrain around semi-exposed submarine cable adapted to time.

From Figure 5, in the first hour of scouring, the upstream (−0.5 m to −0.1 m) and downstream (0.43 m to 1.5 m) scouring holes appeared. The upstream scouring hole was relatively flat with depth of 0.04 m. The depth of the downstream scouring hole increased with the increase in distance, and the maximum depth was 0.13 m. The scouring hole that developed at the wake position was very shallow, and its depth was only 0.007 m.

In the second hour of scouring, the upstream scouring hole’s depth remained nearly constant. The depth of the downstream scouring hole only increased by 0.002 m. The scouring hole at the wake position developed steadily, and its depth increased from 0.007 m to 0.014 m.

The upstream and downstream scouring holes did not continue to develop during the third to the sixth hour. Compared to the first two hours, the development of scouring holes at the wake position accelerated significantly, with an average growth rate of 0.028 m/h. The growth rate in the fifth hour of the scouring hole at the wake position was slightly faster than the other times. After 6 h of scouring, the sediment on the right side of the submarine cable had been hollowed out.

In the seventh and the eighth hour of scouring, the upstream scouring hole’s depth increased slightly, the downstream scouring hole still remained stable, and the depth of the scouring hole at wake position increased by 0.019 m. The sediment under the submarine cable was gradually eroded as well. By the end of the eighth hour, the lower right part of the submarine cable had been exposed to water as well.

At 8 h 21 min of the scouring, the submarine cable was completely spanned, and the scouring holes were connected to each other. Within the next 10 min, the development of the scouring holes sped up significantly, and the maximum depth of scouring holes increased greatly to 0.27 m.

In reference [17], researchers have studied the local scouring process of semi-buried pipelines in sandy riverbeds through experiments. The test results show that the scouring process can be divided into a start-up stage, micropore formation stage, extension stage, and equilibrium stage. In this paper, the first three stages are simulated, and the results are in good agreement with the experiment, which proves the accuracy of the present numerical model.

In this research, the velocity of ocean currents at the sediment surface is defined as the shear velocity, which plays an important role in the process of local scouring. Figure 6 provides visual data on how the shear velocity varies over time.

Jmse 11 01349 g006 550

Figure 6. Shear velocity changes in the scouring process.

The semi-exposed submarine cable protrudes from the seabed, which makes the shear velocity of its surface much higher than other locations. After the submarine cable is spanned, the shear velocity of the scouring hole surface below it is taken. This is the reason for the sudden change of shear velocity at the submarine cable’s location in Figure 6.The shear velocity in the initial state of the upstream scouring hole is obviously greater than in subsequent times. After 1 h of scouring, the shear velocity in the upstream scouring hole rapidly decreased from 1.1 × 10

−2 m/s to 3.98 × 10

−3 m/s and remained stable until the end of the sixth hour. This phenomenon explains why the upstream scouring hole developed rapidly in the first hour but remained stable for the following 5 h.The shear velocity in the downstream scouring hole reduced at first and then increased; its initial value was 1.41 × 10

−2 m/s. It took approximately 5 h for the shear velocity to stabilize, and the stable shear velocity was 2.26 × 10

−3 m/s. Therefore, compared with the upstream scouring hole, the downstream scouring hole was deeper and required more time to reach stability.The initial shear velocity in the scouring hole at the wake position was only 7.1 × 10

−3 m/s, which almost does not change in the first hour. This leads to a very slow development of the scouring hole at the wake position in the early stages. The maximum shear velocity in this scouring hole gradually increased to 1.05 × 10

−2 m/s from the second to the fifth hour, and then decreased to 6.61 × 10

−3 m/s by the end of the eighth hour. This is why the scouring hole at the wake position grows fastest around the fifth hour. Consistent with the pattern of change in the scouring hole’s terrain, the location of the maximal shear velocity also shifted to the right with time.

The shear velocity of all three scouring holes rose dramatically in the last hour. Combined with the terrain in Figure 5, this can be attributed to the complete spanning of the submarine cable.

From Equations (3)–(5), one can see the movement of the sediment is related directly with the sediment’s critical Shields number, sediment density, and ocean current velocity. Based on the parameters in Table 1, the influence of the above parameters on the local scouring process of semi-exposed submarine cables will be discussed.

4.2. Influence Factors

4.2.1. Sediment’s Critical Shields Number

The sediment’s critical Shields number 

θcr is set as 0.02, 0.03, 0.04, 0.05, 0.06, and 0.07, and the variations of scouring terrain over time under each 

θcr are displayed in Figure 7.

Jmse 11 01349 g007 550

Figure 7. Influence of sediment’s critical Shields number 

θcr on local scouring around semi-exposed submarine cable: (a

θcr = 0.02; (b

θcr = 0.03; (c

θcr = 0.04; (d

θcr = 0.05; (e

θcr = 0.06; and (f

θcr = 0.07.From Figure 7, one can see that a change in 

θcr will affect the depth of the upstream scouring hole and the development speed of the scouring hole at the wake position, but it will have no significant impact on the expansion of the downstream scouring hole.Under conditions of different 

θcr, the upstream scouring hole will reach a temporary plateau within 1 h, at which time the stable depth will be about 0.04 m. When 

θcr ≤ 0.05, the upstream scouring hole will continue to expand after a few hours. The stable time is obviously affected by 

θcr, which will gradually increase from 1 h to 11 h with the increase in 

θcr. The terrain of the upstream scouring hole will gradually convert to deep on the left and to shallow on the right. Since the scouring hole at the wake position has not been stable, its state at the time of submarine cable spanning is studied emphatically. In the whole process of scouring, the scouring hole at the wake position continues to develop and does not reach a stable state. With the increase in 

θcr, the development velocity of the scouring hole at the wake position will decrease considerably. Its average evolution velocity decreases from 3.88 cm/h to 1.62 cm/h, and its depth decreases from 21.9 cm to 18.8 cm. Under the condition of each 

θcr, the downstream scouring hole will stabilize within 1 h, and the stable depth will be basically unchanged (all about 13.5 cm).As 

θcr increases, so does the sediment’s ability to withstand shearing forces, which will cause it to become increasingly difficult to be eroded or carried away by ocean currents. This effect has been directly reflected in the depth of scouring holes (upstream and wake position). Due to the blocking effect of semi-exposed submarine cables, the wake is elongated, which is why the downstream scouring hole develops before the scouring hole at the wake position and quickly reaches a stable state. However, due to the high wake intensity, this process is not significantly affected by the change of 

θcr.

4.2.2. Sediment Density

The density of sediment 

ρs is set as 1550 kg/m

3, 1600 kg/m

3, 1650 kg/m

3, 1700 kg/m

3, 1750 kg/m

3, and 1800 kg/m

3, and the variation of scouring terrain over time under each 

ρs are displayed in Figure 8.

Jmse 11 01349 g008 550

Figure 8. Influence of sediment density 

ρs on local scouring around semi-exposed submarine cable: (a

ρs = 1550 kg/m

3; (bρs = 1600 kg/m

3; (cρs = 1650 kg/m

3; (dρs = 1700 kg/m

3; (eρs = 1750 kg/m

3; and (f

ρs = 1800 kg/m

3.From Figure 8, one can see that a change in 

ρs will also affect the depth of the upstream scouring hole and the development speed of the scouring hole at the wake position. In addition, it can even have an impact on the downstream scouring hole depth.Under different 

ρs conditions, the upstream scouring hole will always reach a temporary stable state in 1 h, at which time the stable depth will be 0.04 m. When 

ρs ≤ 1750 kg/m

3, the upstream scouring hole will continue to expand after a few hours. The stabilization time of upstream scouring hole is more clearly affected by 

ρs, which will gradually increase from 3 h to 13 h with the increase in 

ρs. The terrain of the upstream scouring hole will gradually change to deep on the left and to shallow on the right. Since the scouring hole at the wake position has not been stable, its state at the time of the submarine cable spanning is studied emphatically, too. In the whole process of scouring, the scouring hole at the wake position continues to develop and does not reach a stable state. When 

ρs is large, the development rate of scouring hole obviously decreased with time. With the increase in 

ρs, the development velocity of the scouring hole at the wake position reduces from 3.38 cm/h to 1.14 cm/h, and the depth of this scouring hole declines from 20 cm to 15 cm. As 

ρs increases, the stabilization time of the downstream scouring hole increases from less than 1 h to about 2 h, but the stabilization depth of the downstream scouring hole remains essentially the same (all around 13.5 cm).As can be seen from Equation (1), the increase in 

ρs will reduce the Shields number, thus weakening the shear action of the sediment by the ocean current, which explains the extension of the stability time of the upstream scouring hole. At the same time, with the increase in the depth of scouring hole at the wake position, its shear velocity will decreases. Therefore, under a larger 

ρs value, the development speed of scouring hole at the wake position will decrease significantly with time. Possibly for the same reason, 

ρs can affect the development rate of downstream scouring hole.

4.2.3. Ocean Current Velocity

The ocean current velocity v is set as 0.35 m/s, 0.40 m/s, 0.45 m/s, 0.50 m/s, 0.55 m/s, and 0.60 m/s. Figure 9 presents the variation in scouring terrain with time for each v.

Jmse 11 01349 g009 550

Figure 9. Influence of ocean current velocity v on local scouring around semi-exposed submarine cable: (av = 0.35 m/s; (bv = 0.40 m/s; (cv = 0.45 m/s; (dv = 0.50 m/s; (ev = 0.55 m/s; and (fv = 0.60 m/s.

Changes in v affect the depth of the upstream and downstream scouring holes, as well as the development velocity of the wake position and downstream scouring holes.

When v ≤ 0.45 m/s, the upstream scouring hole will reach a temporary stable state within 1 h, at which point the stable depth will be 0.04 m. The stabilization time of the upstream scouring hole is affected by v, which will gradually decrease from 15 h to 3 h with the increase in v. When v > 0.45 m/s, the upstream scouring hole is going to expand continuously. With the increase in v, its average development velocity increases from 6.68 cm/h to 8.66 cm/h, and its terrain changes to deep on the left and to shallow on the right. When the submarine cable is spanning, special attention should be paid to the depth of the scouring hole at the wake position. Throughout whole scouring process, the scouring hole at the wake position continues to develop and does not reach a stable state. With the increase in v, the depth of scouring hole at the wake position will increase from 14 cm to 20 cm, and the average development velocity will increase from 0.91 cm/h to 10.43 cm/h. As v increases, the time required to stabilize the downstream scouring hole is shortened from 1to 2 h to less than 1 h, but the stable depth is remains nearly constant at 13.5 cm.

An increase in v will increase the shear velocity. Therefore, when the depth of the scouring hole increases, the shear velocity in the hole will also increase, which can deepen both the upstream and downstream scouring hole. According to Equation (1), the Shields number is proportional to the square of the shear velocity. The increase in shear velocity significantly intensifies local scouring, which increases the development rate of scouring holes at the wake position and downstream.

4.3. Variation Rule of Spanning Time

In this paper, the spanning time is defined as the time taken for a semi-exposed submarine cable (initial state) to become a spanning submarine cable. Figure 10 illustrates the effect of the above parameters on the spanning time of the semi-exposed submarine cable.

Jmse 11 01349 g010 550

Figure 10. Influence of different parameters on spanning time of the semi-exposed submarine cable: (a) Sediment critical Shields number; (b) Sediment density; and (c) Ocean current velocity.From Figure 10a, the spanning time monotonically increases with the increase in the critical Shields number of sediment. However, the slope of the curve decreases first and then increases, and the inflection point is at 

θcr = 4.59 × 10

−2. The relationship between spanning time t and sediment’s critical Shields number 

θcr can be formulated by a cubic function as shown in Equation (6):

𝑡=−2.98+6.76𝜃𝑐𝑟−1.45𝜃2𝑐𝑟+0.11𝜃3𝑐𝑟.�=−2.98+6.76���−1.45���2+0.11���3.(6)It can be seen from Figure 10b that with the increase in the sediment density, the spanning time increases monotonically and linearly. The relationship between the spanning time t and the sediment’s density 

ρs can be formulated by the first order function as shown in Equation (7):

𝑡=−41.59+30.54𝜌𝑠.�=−41.59+30.54��.(7)Figure 10c shows that with the increase in the ocean current velocity, the spanning time decreases monotonically. The slope of the curve increases with the increase in the ocean current velocity, so it can be considered that there is saturation of the ocean current velocity effect. The relationship between the spanning time t and the ocean current velocity v can be formulated by the exponential function

𝑡=0.15𝑣−4.38.�=0.15�−4.38.(8)

5. Conclusions

In this paper, a three-dimensional CFD finite element numerical simulation model is established, which is used to research the local scouring process of the semi-exposed submarine cable under the steady-state ocean current. The relationship between shear velocity and scouring terrain is discussed, the influence of sediment critical Shields number, sediment density and ocean current velocity on the local scouring process is analyzed, and the variation rules of the spanning time of the semi-exposed submarine cable is given. The conclusions are as follows:

  • Under the steady-state ocean currents, scouring holes will be formed at the upstream, wake position and downstream of the semi-exposed submarine cable. The upstream and downstream scouring holes develop faster, which will reach a temporary stable state at about 1 h after the start of the scouring. The scouring hole at the wake position will continue to expand at a slower rate and eventually lead to the spanning of the submarine cable.
  • There is a close relationship between the distribution of shear velocity and the scouring terrain. As the local scouring process occurs, the location of the maximum shear velocity within the scouring hole shifts and causes the bottom of the hole to move as well.
  • When the sediment’s critical Shields number and density are significantly large and ocean current velocity is sufficiently low, the duration of the stable state of the upstream scouring hole will be prolonged, and the average development velocity of the scouring holes at the wake position and downstream will be reduced.
  • The relationship between the spanning time and the critical Shields number θcr can be formulated as a cubic function, in which the curve’s inflection point is θcr = 4.59 × 10−2. The relationship between spanning time and sediment density can be formulated as a linear function. The relationship between spanning time and ocean current velocity can be formulated by exponential function.

Based on the conclusions of this paper, even when it is too late to take measures or when the exposed position of the submarine cable cannot be located, the degree of burial depth development still can be predicted. This prediction is important for the operation and maintenance of the submarine cable. However, the study still leaves something to be desired. Only the local scouring process under the steady-state ocean current was studied, which is an extreme condition. In practice, exposed submarine cables are more likely to be scoured by reciprocating ocean currents. In the future, we will investigate the local scouring of submarine cables under the reciprocating ocean current.

Author Contributions

Conceptualization, Y.H. and Q.L.; methodology, Q.L., P.Z. and H.T.; software, Q.L.; validation, Q.L., L.C. and W.T.; writing—original draft preparation, Q.L.; writing—review and editing, Y.H. and Q.L.; supervision, Y.H. and L.Y. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the [Smart Grid Joint Fund Key Project between National Natural Science Foundation of China and State Grid Corporation] grant number [U1766220].

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The data supporting the reported results cannot be shared at this time, as they have been used in producing more publications on this research.

Acknowledgments

This work is supported by the Smart Grid Joint Fund Key Project of the National Natural Science Foundation of China and State Grid Corporation (Grant No. U1766220).

Conflicts of Interest

The authors declare no conflict of interest.

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Validity evaluation of popular liquid-vapor phase change models for cryogenic self-pressurization process

극저온 자체 가압 공정을 위한 인기 있는 액체-증기 상 변화 모델의 타당성 평가

액체-증기 상 변화 모델은 밀폐된 용기의 자체 가압 프로세스 시뮬레이션에 매우 큰 영향을 미칩니다. Hertz-Knudsen 관계, 에너지 점프 모델 및 그 파생물과 같은 널리 사용되는 액체-증기 상 변화 모델은 실온 유체를 기반으로 개발되었습니다. 액체-증기 전이를 통한 극저온 시뮬레이션에 널리 적용되었지만 각 모델의 성능은 극저온 조건에서 명시적으로 조사 및 비교되지 않았습니다. 본 연구에서는 171가지 일반적인 액체-증기 상 변화 모델을 통합한 통합 다상 솔버가 제안되었으며, 이를 통해 이러한 모델을 실험 데이터와 직접 비교할 수 있습니다. 증발 및 응축 모델의 예측 정확도와 계산 속도를 평가하기 위해 총 <>개의 자체 가압 시뮬레이션이 수행되었습니다. 압력 예측은 최적화 전략이 서로 다른 모델 계수에 크게 의존하는 것으로 나타났습니다. 에너지 점프 모델은 극저온 자체 가압 시뮬레이션에 적합하지 않은 것으로 나타났습니다. 평균 편차와 CPU 소비량에 따르면 Lee 모델과 Tanasawa 모델은 다른 모델보다 안정적이고 효율적인 것으로 입증되었습니다.

Elsevier

International Journal of Heat and Mass Transfer

Volume 181, December 2021, 121879

International Journal of Heat and Mass Transfer

Validity evaluation of popular liquid-vapor phase change models for cryogenic self-pressurization process

Author links open overlay panelZhongqi Zuo, Jingyi Wu, Yonghua HuangShow moreAdd to MendeleyShareCite

https://doi.org/10.1016/j.ijheatmasstransfer.2021.121879Get rights and content

Abstract

Liquid-vapor phase change models vitally influence the simulation of self-pressurization processes in closed containers. Popular liquid-vapor phase change models, such as the Hertz-Knudsen relation, energy jump model, and their derivations were developed based on room-temperature fluids. Although they had widely been applied in cryogenic simulations with liquid-vapor transitions, the performance of each model was not explicitly investigated and compared yet under cryogenic conditions. A unified multi-phase solver incorporating four typical liquid-vapor phase change models has been proposed in the present study, which enables direct comparison among those models against experimental data. A total number of 171 self-pressurization simulations were conducted to evaluate the evaporation and condensation models’ prediction accuracy and calculation speed. It was found that the pressure prediction highly depended on the model coefficients, whose optimization strategies differed from each other. The energy jump model was found inadequate for cryogenic self-pressurization simulations. According to the average deviation and CPU consumption, the Lee model and the Tanasawa model were proven to be more stable and more efficient than the others.

Introduction

The liquid-vapor phase change of cryogenic fluids is widely involved in industrial applications, such as the hydrogen transport vehicles [1], shipborne liquid natural gas (LNG) containers [2] and on-orbit cryogenic propellant tanks [3]. These applications require cryogenic fluids to be stored for weeks to months. Although high-performance insulation measures are adopted, heat inevitably enters the tank via radiation and conduction. The self-pressurization in the tank induced by the heat leakage eventually causes the venting loss of the cryogenic fluids and threatens the safety of the craft in long-term missions. To reduce the boil-off loss and extend the cryogenic storage duration, a more comprehensive understanding of the self-pressurization mechanism is needed.

Due to the difficulties and limitations in implementing cryogenic experiments, numerical modeling is a convenient and powerful way to study the self-pressurization process of cryogenic fluids. However, how the phase change models influence the mass and heat transfer under cryogenic conditions is still unsettled [4]. As concluded by Persad and Ward [5], a seemingly slight variation in the liquid-vapor phase change models can lead to erroneous predictions.

Among the liquid-vapor phase change models, the kinetic theory gas (KTG) based models and the energy jump model are the most popular ones used in recent self-pressurization simulations [6]. The KTG based models, also known as the Hertz-Knudsen relation models, were developed on the concept of the Maxwell-Boltzmann distribution of the gas molecular [7]. The Hertz-Knudsen relation has evolved to several models, including the Schrage model [8], the Tanasawa model [9], the Lee model [10] and the statistical rate theory (SRT) [11], which will be described in Section 2.2. Since the Schrage model and the Lee model are embedded and configured as the default ones in the commercial CFD solvers Flow-3D® and Ansys Fluent® respectively, they have been widely used in self-pressurization simulations for liquid nitrogen [12], [13] and liquid hydrogen [14], [15]. The major drawback of the KTG models lies in the difficulty of selecting model coefficients, which were reported in a considerably wide range spanning three magnitudes even for the same working fluid [16], [17], [18], [19], [20], [21]. Studies showed that the liquid level, pressure and mass transfer rate are directly influenced by the model coefficients [16], [22], [23], [24], [25]. Wrong coefficients will lead to deviation or even divergence of the results. The energy jump model is also known as the thermal limitation model. It assumes that the evaporation and condensation at the liquid-vapor interface are induced only by heat conduction. The model is widely adopted in lumped node simulations due to its simplicity [6], [26], [27]. To improve the accuracy of mass flux prediction, the energy jump model was modified by including the convection heat transfer [28], [29]. However, the convection correlations are empirical and developed mainly for room-temperature fluids. Whether the correlation itself can be precisely applied in cryogenic simulations still needs further investigation.

Fig. 1 summarizes the cryogenic simulations involving the modeling of evaporation and condensation processes in recent years. The publication has been increasing rapidly. However, the characteristics of each evaporation and condensation model are not explicitly revealed when simulating self-pressurization. A comparative study of the phase change models is highly needed for cryogenic fluids for a better simulation of the self-pressurization processes.

In the present paper, a unified multi-phase solver incorporating four typical liquid-vapor phase change models, namely the Tanasawa model, the Lee model, the energy jump model, and the modified energy jump model has been proposed, which enables direct comparison among different models. The models are used to simulate the pressure and temperature evolutions in an experimental liquid nitrogen tank in normal gravity, which helps to evaluate themselves in the aspects of accuracy, calculation speed and robustness.

Section snippets

Governing equations for the self-pressurization tank

In the present study, both the fluid domain and the solid wall of the tank are modeled and discretized. The heat transportation at the solid boundaries is considered to be irrelevant with the nearby fluid velocity. Consequently, two sets of the solid and the fluid governing equations can be decoupled and solved separately. The pressures in the cryogenic container are usually from 100 kPa to 300 kPa. Under these conditions, the Knudsen number is far smaller than 0.01, and the fluids are

Self-pressurization results and phase change model comparison

This section compares the simulation results by different phase change models. Section 3.1 compares the pressure and temperature outputs from two KTG based models, namely the Lee model and the Tanasawa model. Section 3.2 presents the pressure predictions from the energy transport models, namely the energy jump model and the modified energy jump model, and compares pressure prediction performances between the KTG based models and the energy transport models. Section 3.3 evaluates the four models 

Conclusion

A unified vapor-liquid-solid multi-phase numerical solver has been accomplished for the self pressurization simulation in cryogenic containers. Compared to the early fluid-only solver, the temperature prediction in the vicinity of the tank wall improves significantly. Four liquid-vapor phase change models were integrated into the solver, which enables fair and effective comparison for performances between each other. The pressure and temperature prediction accuracies, and the calculation speed

CRediT authorship contribution statement

Zhongqi Zuo: Data curation, Formal analysis, Writing – original draft, Validation. Jingyi Wu: Conceptualization, Writing – review & editing, Validation. Yonghua Huang: Conceptualization, Formal analysis, Writing – review & editing, Validation.

Declaration of Competing Interest

Authors declare that they have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled, “Validity evaluation of popular liquid-vapor phase change models for cryogenic self-pressurization process”.

Acknowledgement

This project is supported by the National Natural Science Foundation of China (No. 51936006).

References (40)

There are more references available in the full text version of this article.

Cited by (7)

Effects of surface roughness on overflow discharge of embankment weirs

표면 거칠기가 제방 둑의 오버플로 배출에 미치는 영향

Effects of surface roughness on overflow discharge of embankment weirs

Abstract

A numerical study was performed on the embankment weir overflows with various surface roughness and tailwater submergence, to better understand the effects of weir roughness on discharge performances under the free and submerged conditions. The variation of flow regime is captured, from the free overflow, submerged hydraulic jump, to surface flow with increasing tailwater depth. A roughness factor is introduced to reflect the reduction in discharge caused by weir roughness. The roughness factor decreases with the roughness height, and it also depends on the tailwater depth, highlighting various relations of the roughness factor with the roughness height between different flow regimes, which is linear for the free overflow and submerged hydraulic jump while exponential for the surface flow. Accordingly, the effects of weir roughness on overflow discharge appear nonnegligible for the significant roughness height and the surface flow regime occurring under considerable tailwater submergence. The established empirical expressions of discharge coefficient and submergence and roughness factors make it possible to predict the discharge over embankment weirs considering both tailwater submergence and surface roughness.

자유 및 침수 조건에서 방류 성능에 대한 둑 거칠기의 영향을 더 잘 이해하기 위해 다양한 표면 거칠기와 테일워터 침수를 갖는 제방 둑 범람에 대한 수치 연구가 수행되었습니다.

자유 범람, 수중 수압 점프, 테일워터 깊이가 증가하는 표면 유동에 이르기까지 유동 체제의 변화가 캡처됩니다. 위어 거칠기로 인한 배출 감소를 반영하기 위해 거칠기 계수가 도입되었습니다.

조도 계수는 조도 높이와 함께 감소하고, 또한 테일워터 깊이에 따라 달라지며, 서로 다른 흐름 영역 사이의 조도 높이와 조도 계수의 다양한 관계를 강조합니다.

이는 자유 범람 및 수중 수압 점프에 대해 선형인 반면 표면에 대해 지수적입니다. 흐름. 따라서 월류 방류에 대한 웨어 조도의 영향은 상당한 조도 높이와 상당한 방수 침수 하에서 발생하는 표면 흐름 체제에 대해 무시할 수 없는 것으로 보입니다.

방류계수와 침수 및 조도계수의 확립된 실증식은 방류수 침수와 지표조도를 모두 고려한 제방보 위의 방류량을 예측할 수 있게 합니다.

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Figure 11. Sketch of scour mechanism around USAF under random waves.

Scour Characteristics and Equilibrium Scour Depth Prediction around Umbrella Suction Anchor Foundation under Random Waves

by Ruigeng Hu 1,Hongjun Liu 2,Hao Leng 1,Peng Yu 3 andXiuhai Wang 1,2,*

1College of Environmental Science and Engineering, Ocean University of China, Qingdao 266000, China

2Key Lab of Marine Environment and Ecology (Ocean University of China), Ministry of Education, Qingdao 266000, China

3Qingdao Geo-Engineering Survering Institute, Qingdao 266100, China

*Author to whom correspondence should be addressed.

J. Mar. Sci. Eng. 20219(8), 886; https://doi.org/10.3390/jmse9080886

Received: 6 July 2021 / Revised: 8 August 2021 / Accepted: 13 August 2021 / Published: 17 August 2021

(This article belongs to the Section Ocean Engineering)

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Abstract

A series of numerical simulation were conducted to study the local scour around umbrella suction anchor foundation (USAF) under random waves. In this study, the validation was carried out firstly to verify the accuracy of the present model. Furthermore, the scour evolution and scour mechanism were analyzed respectively. In addition, two revised models were proposed to predict the equilibrium scour depth Seq around USAF. At last, a parametric study was carried out to study the effects of the Froude number Fr and Euler number Eu for the Seq. The results indicate that the present numerical model is accurate and reasonable for depicting the scour morphology under random waves. The revised Raaijmakers’s model shows good agreement with the simulating results of the present study when KCs,p < 8. The predicting results of the revised stochastic model are the most favorable for n = 10 when KCrms,a < 4. The higher Fr and Eu both lead to the more intensive horseshoe vortex and larger Seq.

Keywords: 

scournumerical investigationrandom wavesequilibrium scour depthKC number

1. Introduction

The rapid expansion of cities tends to cause social and economic problems, such as environmental pollution and traffic jam. As a kind of clean energy, offshore wind power has developed rapidly in recent years. The foundation of offshore wind turbine (OWT) supports the upper tower, and suffers the cyclic loading induced by waves, tides and winds, which exerts a vital influence on the OWT system. The types of OWT foundation include the fixed and floating foundation, and the fixed foundation was used usually for nearshore wind turbine. After the construction of fixed foundation, the hydrodynamic field changes in the vicinity of the foundation, leading to the horseshoe vortex formation and streamline compression at the upside and sides of foundation respectively [1,2,3,4]. As a result, the neighboring soil would be carried away by the shear stress induced by vortex, and the scour hole would emerge in the vicinity of foundation. The scour holes increase the cantilever length, and weaken the lateral bearing capacity of foundation [5,6,7,8,9]. Moreover, the natural frequency of OWT system increases with the increase of cantilever length, causing the resonance occurs when the system natural frequency equals the wave or wind frequency [10,11,12]. Given that, an innovative foundation called umbrella suction anchor foundation (USAF) has been designed for nearshore wind power. The previous studies indicated the USAF was characterized by the favorable lateral bearing capacity with the low cost [6,13,14]. The close-up of USAF is shown in Figure 1, and it includes six parts: 1-interal buckets, 2-external skirt, 3-anchor ring, 4-anchor branch, 5-supporting rod, 6-telescopic hook. The detailed description and application method of USAF can be found in reference [13].

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Figure 1. The close-up of umbrella suction anchor foundation (USAF).

Numerical and experimental investigations of scour around OWT foundation under steady currents and waves have been extensively studied by many researchers [1,2,15,16,17,18,19,20,21,22,23,24]. The seabed scour can be classified as two types according to Shields parameter θ, i.e., clear bed scour (θ < θcr) or live bed scour (θ > θcr). Due to the set of foundation, the adverse hydraulic pressure gradient exists at upstream foundation edges, resulting in the streamline separation between boundary layer flow and seabed. The separating boundary layer ascended at upstream anchor edges and developed into the horseshoe vortex. Then, the horseshoe vortex moved downstream gradually along the periphery of the anchor, and the vortex shed off continually at the lee-side of the anchor, i.e., wake vortex. The core of wake vortex is a negative pressure center, liking a vacuum cleaner. Hence, the soil particles were swirled into the negative pressure core and carried away by wake vortexes. At the same time, the onset of scour at rear side occurred. Finally, the wake vortex became downflow when the turbulence energy could not support the survival of wake vortex. According to Tavouktsoglou et al. [25], the scale of pile wall boundary layer is proportional to 1/ln(Rd) (Rd is pile Reynolds), which means the turbulence intensity induced by the flow-structure interaction would decrease with Rd increases, but the effects of Rd can be neglected only if the flow around the foundation is fully turbulent [26]. According to previous studies [1,15,27,28,29,30,31,32], the scour development around pile foundation under waves was significantly influenced by Shields parameter θ and KC number simultaneously (calculated by Equation (1)). Sand ripples widely existed around pile under waves in the case of live bed scour, and the scour morphology is related with θ and KC. Compared with θKC has a greater influence on the scour morphology [21,27,28]. The influence mechanism of KC on the scour around the pile is reflected in two aspects: the horseshoe vortex at upstream and wake vortex shedding at downstream.

KC=UwmTD��=�wm��(1)

where, Uwm is the maximum velocity of the undisturbed wave-induced oscillatory flow at the sea bottom above the wave boundary layer, T is wave period, and D is pile diameter.

There are two prerequisites to satisfy the formation of horseshoe vortex at upstream pile edges: (1) the incoming flow boundary layer with sufficient thickness and (2) the magnitude of upstream adverse pressure gradient making the boundary layer separating [1,15,16,18,20]. The smaller KC results the lower adverse pressure gradient, and the boundary layer cannot separate, herein, there is almost no horseshoe vortex emerging at upside of pile. Sumer et al. [1,15] carried out several sets of wave flume experiments under regular and irregular waves respectively, and the experiment results show that there is no horseshoe vortex when KC is less than 6. While the scale and lifespan of horseshoe vortex increase evidently with the increase of KC when KC is larger than 6. Moreover, the wake vortex contributes to the scour at lee-side of pile. Similar with the case of horseshoe vortex, there is no wake vortex when KC is less than 6. The wake vortex is mainly responsible for scour around pile when KC is greater than 6 and less than O(100), while horseshoe vortex controls scour nearly when KC is greater than O(100).

Sumer et al. [1] found that the equilibrium scour depth was nil around pile when KC was less than 6 under regular waves for live bed scour, while the equilibrium scour depth increased with the increase of KC. Based on that, Sumer proposed an equilibrium scour depth predicting equation (Equation (2)). Carreiras et al. [33] revised Sumer’s equation with m = 0.06 for nonlinear waves. Different with the findings of Sumer et al. [1] and Carreiras et al. [33], Corvaro et al. [21] found the scour still occurred for KC ≈ 4, and proposed the revised equilibrium scour depth predicting equation (Equation (3)) for KC > 4.

Rudolph and Bos [2] conducted a series of wave flume experiments to investigate the scour depth around monopile under waves only, waves and currents combined respectively, indicting KC was one of key parameters in influencing equilibrium scour depth, and proposed the equilibrium scour depth predicting equation (Equation (4)) for low KC (1 < KC < 10). Through analyzing the extensive data from published literatures, Raaijmakers and Rudolph [34] developed the equilibrium scour depth predicting equation (Equation (5)) for low KC, which was suitable for waves only, waves and currents combined. Khalfin [35] carried out several sets of wave flume experiments to study scour development around monopile, and proposed the equilibrium scour depth predicting equation (Equation (6)) for low KC (0.1 < KC < 3.5). Different with above equations, the Khalfin’s equation considers the Shields parameter θ and KC number simultaneously in predicting equilibrium scour depth. The flow reversal occurred under through in one wave period, so sand particles would be carried away from lee-side of pile to upside, resulting in sand particles backfilled into the upstream scour hole [20,29]. Considering the backfilling effects, Zanke et al. [36] proposed the equilibrium scour depth predicting equation (Equation (7)) around pile by theoretical analysis, and the equation is suitable for the whole range of KC number under regular waves and currents combined.

S/D=1.3(1−exp([−m(KC−6)])�/�=1.3(1−exp(−�(��−6))(2)

where, m = 0.03 for linear waves.

S/D=1.3(1−exp([−0.02(KC−4)])�/�=1.3(1−exp(−0.02(��−4))(3)

S/D=1.3γKwaveKhw�/�=1.3��wave�ℎw(4)

where, γ is safety factor, depending on design process, typically γ = 1.5, Kwave is correction factor considering wave action, Khw is correction factor considering water depth.

S/D=1.5[tanh(hwD)]KwaveKhw�/�=1.5tanh(ℎw�)�wave�ℎw(5)

where, hw is water depth.

S/D=0.0753(θθcr−−−√−0.5)0.69KC0.68�/�=0.0753(��cr−0.5)0.69��0.68(6)

where, θ is shields parameter, θcr is critical shields parameter.

S/D=2.5(1−0.5u/uc)xrelxrel=xeff/(1+xeff)xeff=0.03(1−0.35ucr/u)(KC−6)⎫⎭⎬⎪⎪�/�=2.5(1−0.5�/��)��������=����/(1+����)����=0.03(1−0.35�cr/�)(��−6)(7)

where, u is near-bed orbital velocity amplitude, uc is critical velocity corresponding the onset of sediment motion.

S/D=1.3{1−exp[−0.03(KC2lnn+36)1/2−6]}�/�=1.31−exp−0.03(��2ln�+36)1/2−6(8)

where, n is the 1/n’th highest wave for random waves

For predicting equilibrium scour depth under irregular waves, i.e., random waves, Sumer and Fredsøe [16] found it’s suitable to take Equation (2) to predict equilibrium scour depth around pile under random waves with the root-mean-square (RMS) value of near-bed orbital velocity amplitude Um and peak wave period TP to calculate KC. Khalfin [35] recommended the RMS wave height Hrms and peak wave period TP were used to calculate KC for Equation (6). References [37,38,39,40] developed a series of stochastic theoretical models to predict equilibrium scour depth around pile under random waves, nonlinear random waves plus currents respectively. The stochastic approach thought the 1/n’th highest wave were responsible for scour in vicinity of pile under random waves, and the KC was calculated in Equation (8) with Um and mean zero-crossing wave period Tz. The results calculated by Equation (8) agree well with experimental values of Sumer and Fredsøe [16] if the 1/10′th highest wave was used. To author’s knowledge, the stochastic approach proposed by Myrhaug and Rue [37] is the only theoretical model to predict equilibrium scour depth around pile under random waves for the whole range of KC number in published documents. Other methods of predicting scour depth under random waves are mainly originated from the equation for regular waves-only, waves and currents combined, which are limited to the large KC number, such as KC > 6 for Equation (2) and KC > 4 for Equation (3) respectively. However, situations with relatively low KC number (KC < 4) often occur in reality, for example, monopile or suction anchor for OWT foundations in ocean environment. Moreover, local scour around OWT foundations under random waves has not yet been investigated fully. Therefore, further study are still needed in the aspect of scour around OWT foundations with low KC number under random waves. Given that, this study presents the scour sediment model around umbrella suction anchor foundation (USAF) under random waves. In this study, a comparison of equilibrium scour depth around USAF between this present numerical models and the previous theoretical models and experimental results was presented firstly. Then, this study gave a comprehensive analysis for the scour mechanisms around USAF. After that, two revised models were proposed according to the model of Raaijmakers and Rudolph [34] and the stochastic model developed by Myrhaug and Rue [37] respectively to predict the equilibrium scour depth. Finally, a parametric study was conducted to study the effects of the Froude number (Fr) and Euler number (Eu) to equilibrium scour depth respectively.

2. Numerical Method

2.1. Governing Equations of Flow

The following equations adopted in present model are already available in Flow 3D software. The authors used these theoretical equations to simulate scour in random waves without modification. The incompressible viscous fluid motion satisfies the Reynolds-averaged Navier-Stokes (RANS) equation, so the present numerical model solves RANS equations:

∂u∂t+1VF(uAx∂u∂x+vAy∂u∂y+wAz∂u∂z)=−1ρf∂p∂x+Gx+fx∂�∂�+1��(���∂�∂�+���∂�∂�+���∂�∂�)=−1�f∂�∂�+��+��(9)

∂v∂t+1VF(uAx∂v∂x+vAy∂v∂y+wAz∂v∂z)=−1ρf∂p∂y+Gy+fy∂�∂�+1��(���∂�∂�+���∂�∂�+���∂�∂�)=−1�f∂�∂�+��+��(10)

∂w∂t+1VF(uAx∂w∂x+vAy∂w∂y+wAz∂w∂z)=−1ρf∂p∂z+Gz+fz∂�∂�+1��(���∂�∂�+���∂�∂�+���∂�∂�)=−1�f∂�∂�+��+��(11)

where, VF is the volume fraction; uv, and w are the velocity components in xyz direction respectively with Cartesian coordinates; Ai is the area fraction; ρf is the fluid density, fi is the viscous fluid acceleration, Gi is the fluid body acceleration (i = xyz).

2.2. Turbulent Model

The turbulence closure is available by the turbulent model, such as one-equation, the one-equation k-ε model, the standard k-ε model, RNG k-ε turbulent model and large eddy simulation (LES) model. The LES model requires very fine mesh grid, so the computational time is large, which hinders the LES model application in engineering. The RNG k-ε model can reduce computational time greatly with high accuracy in the near-wall region. Furthermore, the RNG k-ε model computes the maximum turbulent mixing length dynamically in simulating sediment scour model. Therefore, the RNG k-ε model was adopted to study the scour around anchor under random waves [41,42].

∂kT∂T+1VF(uAx∂kT∂x+vAy∂kT∂y+wAz∂kT∂z)=PT+GT+DiffkT−εkT∂��∂�+1��(���∂��∂�+���∂��∂�+���∂��∂�)=��+��+������−���(12)

∂εT∂T+1VF(uAx∂εT∂x+vAy∂εT∂y+wAz∂εT∂z)=CDIS1εTkT(PT+CDIS3GT)+Diffε−CDIS2ε2TkT∂��∂�+1��(���∂��∂�+���∂��∂�+���∂��∂�)=����1����(��+����3��)+�����−����2��2��(13)

where, kT is specific kinetic energy involved with turbulent velocity, GT is the turbulent energy generated by buoyancy; εT is the turbulent energy dissipating rate, PT is the turbulent energy, Diffε and DiffkT are diffusion terms associated with VFAiCDIS1CDIS2 and CDIS3 are dimensionless parameters, and CDIS1CDIS3 have default values of 1.42, 0.2 respectively. CDIS2 can be obtained from PT and kT.

2.3. Sediment Scour Model

The sand particles may suffer four processes under waves, i.e., entrainment, bed load transport, suspended load transport, and deposition, so the sediment scour model should depict the above processes efficiently. In present numerical simulation, the sediment scour model includes the following aspects:

2.3.1. Entrainment and Deposition

The combination of entrainment and deposition determines the net scour rate of seabed in present sediment scour model. The entrainment lift velocity of sand particles was calculated as [43]:

ulift,i=αinsd0.3∗(θ−θcr)1.5∥g∥di(ρi−ρf)ρf−−−−−−−−−−−−√�lift,i=�����*0.3(�−�cr)1.5���(��−�f)�f(14)

where, αi is the entrainment parameter, ns is the outward point perpendicular to the seabed, d* is the dimensionless diameter of sand particles, which was calculated by Equation (15), θcr is the critical Shields parameter, g is the gravity acceleration, di is the diameter of sand particles, ρi is the density of seabed species.

d∗=di(∥g∥ρf(ρi−ρf)μ2f)1/3�*=��(��f(��−�f)�f2)1/3(15)

where μf is the fluid dynamic viscosity.

In Equation (14), the entrainment parameter αi confirms the rate at which sediment erodes when the given shear stress is larger than the critical shear stress, and the recommended value 0.018 was adopted according to the experimental data of Mastbergen and Von den Berg [43]. ns is the outward pointing normal to the seabed interface, and ns = (0,0,1) according to the Cartesian coordinates used in present numerical model.

The shields parameter was obtained from the following equation:

θ=U2f,m(ρi/ρf−1)gd50�=�f,m2(��/�f−1)��50(16)

where, Uf,m is the maximum value of the near-bed friction velocity; d50 is the median diameter of sand particles. The detailed calculation procedure of θ was available in Soulsby [44].

The critical shields parameter θcr was obtained from the Equation (17) [44]

θcr=0.31+1.2d∗+0.055[1−exp(−0.02d∗)]�cr=0.31+1.2�*+0.0551−exp(−0.02�*)(17)

The sand particles begin to deposit on seabed when the turbulence energy weaken and cann’t support the particles suspending. The setting velocity of the particles was calculated from the following equation [44]:

usettling,i=νfdi[(10.362+1.049d3∗)0.5−10.36]�settling,�=�f��(10.362+1.049�*3)0.5−10.36(18)

where νf is the fluid kinematic viscosity.

2.3.2. Bed Load Transport

This is called bed load transport when the sand particles roll or bounce over the seabed and always have contact with seabed. The bed load transport velocity was computed by [45]:

ubedload,i=qb,iδicb,ifb�bedload,�=�b,����b,��b(19)

where, qb,i is the bed load transport rate, which was obtained from Equation (20), δi is the bed load thickness, which was calculated by Equation (21), cb,i is the volume fraction of sand i in the multiple species, fb is the critical packing fraction of the seabed.

qb,i=8[∥g∥(ρi−ρfρf)d3i]1/2�b,�=8�(��−�f�f)��31/2(20)

δi=0.3d0.7∗(θθcr−1)0.5di��=0.3�*0.7(��cr−1)0.5��(21)

2.3.3. Suspended Load Transport

Through the following transport equation, the suspended sediment concentration could be acquired.

∂Cs,i∂t+∇(us,iCs,i)=∇∇(DfCs,i)∂�s,�∂�+∇(�s,��s,�)=∇∇(�f�s,�)(22)

where, Cs,i is the suspended sand particles mass concentration of sand i in the multiple species, us,i is the sand particles velocity of sand iDf is the diffusivity.

The velocity of sand i in the multiple species could be obtained from the following equation:

us,i=u¯¯+usettling,ics,i�s,�=�¯+�settling,��s,�(23)

where, u¯�¯ is the velocity of mixed fluid-particles, which can be calculated by the RANS equation with turbulence model, cs,i is the suspended sand particles volume concentration, which was computed from Equation (24).

cs,i=Cs,iρi�s,�=�s,���(24)

3. Model Setup

The seabed-USAF-wave three-dimensional scour numerical model was built using Flow-3D software. As shown in Figure 2, the model includes sandy seabed, USAF model, sea water, two baffles and porous media. The dimensions of USAF are shown in Table 1. The sandy bed (210 m in length, 30 m in width and 11 m in height) is made up of uniform fine sand with median diameter d50 = 0.041 cm. The USAF model includes upper steel tube with the length of 20 m, which was installed in the middle of seabed. The location of USAF is positioned at 140 m from the upstream inflow boundary and 70 m from the downstream outflow boundary. Two baffles were installed at two ends of seabed. In order to eliminate the wave reflection basically, the porous media was set at the outflow side on the seabed.

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Figure 2. (a) The sketch of seabed-USAF-wave three-dimensional model; (b) boundary condation:Wv-wave boundary, S-symmetric boundary, O-outflow boundary; (c) USAF model.

Table 1. Numerical simulating cases.

Table

3.1. Mesh Geometric Dimensions

In the simulation of the scour under the random waves, the model includes the umbrella suction anchor foundation, seabed and fluid. As shown in Figure 3, the model mesh includes global mesh grid and nested mesh grid, and the total number of grids is 1,812,000. The basic procedure for building mesh grid consists of two steps. Step 1: Divide the global mesh using regular hexahedron with size of 0.6 × 0.6. The global mesh area is cubic box, embracing the seabed and whole fluid volume, and the dimensions are 210 m in length, 30 m in width and 32 m in height. The details of determining the grid size can see the following mesh sensitivity section. Step 2: Set nested fine mesh grid in vicinity of the USAF with size of 0.3 × 0.3 so as to shorten the computation cost and improve the calculation accuracy. The encryption range is −15 m to 15 m in x direction, −15 m to 15 m in y direction and 0 m to 32 m in z direction, respectively. In order to accurately capture the free-surface dynamics, such as the fluid-air interface, the volume of fluid (VOF) method was adopted for tracking the free water surface. One specific algorithm called FAVORTM (Fractional Area/Volume Obstacle Representation) was used to define the fractional face areas and fractional volumes of the cells which are open to fluid flow.

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Figure 3. The sketch of mesh grid.

3.2. Boundary Conditions

As shown in Figure 2, the initial fluid length is 210 m as long as seabed. A wave boundary was specified at the upstream offshore end. The details of determining the random wave spectrum can see the following wave parameters section. The outflow boundary was set at the downstream onshore end. The symmetry boundary was used at the top and two sides of the model. The symmetric boundaries were the better strategy to improve the computation efficiency and save the calculation cost [46]. At the seabed bottom, the wall boundary was adopted, which means the u = v = w= 0. Besides, the upper steel tube of USAF was set as no-slip condition.

3.3. Wave Parameters

The random waves with JONSWAP wave spectrum were used for all simulations as realistic representation of offshore conditions. The unidirectional JONSWAP frequency spectrum was described as [47]:

S(ω)=αg2ω5exp[−54(ωpω)4]γexp[−(ω−ωp)22σ2ω2p]�(�)=��2�5exp−54(�p�)4�exp−(�−�p)22�2�p2(25)

where, α is wave energy scale parameter, which is calculated by Equation (26), ω is frequency, ωp is wave spectrum peak frequency, which can be obtained from Equation (27). γ is wave spectrum peak enhancement factor, in this study γ = 3.3. σ is spectral width factor, σ equals 0.07 for ω ≤ ωp and 0.09 for ω > ωp respectively.

α=0.0076(gXU2)−0.22�=0.0076(���2)−0.22(26)

ωp=22(gU)(gXU2)−0.33�p=22(��)(���2)−0.33(27)

where, X is fetch length, U is average wind velocity at 10 m height from mean sea level.

In present numerical model, the input key parameters include X and U for wave boundary with JONSWAP wave spectrum. The objective wave height and period are available by different combinations of X and U. In this study, we designed 9 cases with different wave heights, periods and water depths for simulating scour around USAF under random waves (see Table 2). For random waves, the wave steepness ε and Ursell number Ur were acquired form Equations (28) and (29) respectively

ε=2πgHsT2a�=2���s�a2(28)

Ur=Hsk2h3w�r=�s�2ℎw3(29)

where, Hs is significant wave height, Ta is average wave period, k is wave number, hw is water depth. The Shield parameter θ satisfies θ > θcr for all simulations in current study, indicating the live bed scour prevails.

Table 2. Numerical simulating cases.

Table

3.4. Mesh Sensitivity

In this section, a mesh sensitivity analysis was conducted to investigate the influence of mesh grid size to results and make sure the calculation is mesh size independent and converged. Three mesh grid size were chosen: Mesh 1—global mesh grid size of 0.75 × 0.75, nested fine mesh grid size of 0.4 × 0.4, and total number of grids 1,724,000, Mesh 2—global mesh grid size of 0.6 × 0.6, nested fine mesh grid size of 0.3 × 0.3, and total number of grids 1,812,000, Mesh 3—global mesh grid size of 0.4 × 0.4, nested fine mesh grid size of 0.2 × 0.2, and total number of grids 1,932,000. The near-bed shear velocity U* is an important factor for influencing scour process [1,15], so U* at the position of (4,0,11.12) was evaluated under three mesh sizes. As the Figure 4 shown, the maximum error of shear velocity ∆U*1,2 is about 39.8% between the mesh 1 and mesh 2, and 4.8% between the mesh 2 and mesh 3. According to the mesh sensitivity criterion adopted by Pang et al. [48], it’s reasonable to think the results are mesh size independent and converged with mesh 2. Additionally, the present model was built according to prototype size, and the mesh size used in present model is larger than the mesh size adopted by Higueira et al. [49] and Corvaro et al. [50]. If we choose the smallest cell size, it will take too much time. For example, the simulation with Mesh3 required about 260 h by using a computer with Intel Xeon Scalable Gold 4214 CPU @24 Cores, 2.2 GHz and 64.00 GB RAM. Therefore, in this case, considering calculation accuracy and computation efficiency, the mesh 2 was chosen for all the simulation in this study.

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Figure 4. Comparison of near-bed shear velocity U* with different mesh grid size.

The nested mesh block was adopted for seabed in vicinity of the USAF, which was overlapped with the global mesh block. When two mesh blocks overlap each other, the governing equations are by default solved on the mesh block with smaller average cell size (i.e., higher grid resolution). It is should be noted that the Flow 3D software used the moving mesh captures the scour evolution and automatically adjusts the time step size to be as large as possible without exceeding any of the stability limits, affecting accuracy, or unduly increasing the effort required to enforce the continuity condition [51].

3.5. Model Validation

In order to verify the reliability of the present model, the results of present study were compared with the experimental data of Khosronejad et al. [52]. The experiment was conducted in an open channel with a slender vertical pile under unidirectional currents. The comparison of scour development between the present results and the experimental results is shown in Figure 5. The Figure 5 reveals that the present results agree well with the experimental data of Khosronejad et al. [52]. In the first stage, the scour depth increases rapidly. After that, the scour depth achieves a maximum value gradually. The equilibrium scour depth calculated by the present model is basically corresponding with the experimental results of Khosronejad et al. [52], although scour depth in the present model is slightly larger than the experimental results at initial stage.

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Figure 5. Comparison of time evolution of scour between the present study and Khosronejad et al. [52], Petersen et al. [17].

Secondly, another comparison was further conducted between the results of present study and the experimental data of Petersen et al. [17]. The experiment was carried out in a flume with a circular vertical pile in combined waves and current. Figure 4 shows a comparison of time evolution of scour depth between the simulating and the experimental results. As Figure 5 indicates, the scour depth in this study has good overall agreement with the experimental results proposed in Petersen et al. [17]. The equilibrium scour depth calculated by the present model is 0.399 m, which equals to the experimental value basically. Overall, the above verifications prove the present model is accurate and capable in dealing with sediment scour under waves.

In addition, in order to calibrate and validate the present model for hydrodynamic parameters, the comparison of water surface elevation was carried out with laboratory experiments conducted by Stahlmann [53] for wave gauge No. 3. The Figure 6 depicts the surface wave profiles between experiments and numerical model results. The comparison indicates that there is a good agreement between the model results and experimental values, especially the locations of wave crest and trough. Comparison of the surface elevation instructs the present model has an acceptable relative error, and the model is a calibrated in terms of the hydrodynamic parameters.

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Figure 6. Comparison of surface elevation between the present study and Stahlmann [53].

Finally, another comparison was conducted for equilibrium scour depth or maximum scour depth under random waves with the experimental data of Sumer and Fredsøe [16] and Schendel et al. [22]. The Figure 7 shows the comparison between the numerical results and experimental data of Run01, Run05, Run21 and Run22 in Sumer and Fredsøe [16] and test A05 and A09 in Schendel et al. [22]. As shown in Figure 7, the equilibrium scour depth or maximum scour depth distributed within the ±30 error lines basically, meaning the reliability and accuracy of present model for predicting equilibrium scour depth around foundation in random waves. However, compared with the experimental values, the present model overestimated the equilibrium scour depth generally. Given that, a calibration for scour depth was carried out by multiplying the mean reduced coefficient 0.85 in following section.

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Figure 7. Comparison of equilibrium (or maximum) scour depth between the present study and Sumer and Fredsøe [16], Schendel et al. [22].

Through the various examination for hydrodynamic and morphology parameters, it can be concluded that the present model is a validated and calibrated model for scour under random waves. Thus, the present numerical model would be utilized for scour simulation around foundation under random waves.

4. Numerical Results and Discussions

4.1. Scour Evolution

Figure 8 displays the scour evolution for case 1–9. As shown in Figure 8a, the scour depth increased rapidly at the initial stage, and then slowed down at the transition stage, which attributes to the backfilling occurred in scour holes under live bed scour condition, resulting in the net scour decreasing. Finally, the scour reached the equilibrium state when the amount of sediment backfilling equaled to that of scouring in the scour holes, i.e., the net scour transport rate was nil. Sumer and Fredsøe [16] proposed the following formula for the scour development under waves

St=Seq(1−exp(−t/Tc))�t=�eq(1−exp(−�/�c))(30)

where Tc is time scale of scour process.

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Figure 8. Time evolution of scour for case 1–9: (a) Case 1–5; (b) Case 6–9.

The computing time is 3600 s and the scour development curves in Figure 8 kept fluctuating, meaning it’s still not in equilibrium scour stage in these cases. According to Sumer and Fredsøe [16], the equilibrium scour depth can be acquired by fitting the data with Equation (30). From Figure 8, it can be seen that the scour evolution obtained from Equation (30) is consistent with the present study basically at initial stage, but the scour depth predicted by Equation (30) developed slightly faster than the simulating results and the Equation (30) overestimated the scour depth to some extent. Overall, the whole tendency of the results calculated by Equation (30) agrees well with the simulating results of the present study, which means the Equation (30) is applicable to depict the scour evolution around USAF under random waves.

4.2. Scour Mechanism under Random Waves

The scour morphology and scour evolution around USAF are similar under random waves in case 1~9. Taking case 7 as an example, the scour morphology is shown in Figure 9.

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Figure 9. Scour morphology under different times for case 7.

From Figure 9, at the initial stage (t < 1200 s), the scour occurred at upstream foundation edges between neighboring anchor branches. The maximum scour depth appeared at the lee-side of the USAF. Correspondingly, the sediments deposited at the periphery of the USAF, and the location of the maximum accretion depth was positioned at an angle of about 45° symmetrically with respect to the wave propagating direction in the lee-side of the USAF. After that, when t > 2400 s, the location of the maximum scour depth shifted to the upside of the USAF at an angle of about 45° with respect to the wave propagating direction.

According to previous studies [1,15,16,19,30,31], the horseshoe vortex, streamline compression and wake vortex shedding were responsible for scour around foundation. The Figure 10 displays the distribution of flow velocity in vicinity of foundation, which reflects the evolving processes of horseshoe vertex.

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Figure 10. Velocity profile around USAF: (a) Flow runup and down stream at upstream anchor edges; (b) Horseshoe vortex at upstream anchor edges; (c) Flow reversal during wave through stage at lee side.

As shown in Figure 10, the inflow tripped to the upstream edges of the USAF and it was blocked by the upper tube of USAF. Then, the downflow formed the horizontal axis clockwise vortex and rolled on the seabed bypassing the tube, that is, the horseshoe vortex (Figure 11). The Figure 12 displays the turbulence intensity around the tube on the seabed. From Figure 12, it can be seen that the turbulence intensity was high-intensity with respect to the region of horseshoe vortex. This phenomenon occurred because of drastic water flow momentum exchanging in the horseshoe vortex. As a result, it created the prominent shear stress on the seabed, causing the local scour at the upstream edges of USAF. Besides, the horseshoe vortex moved downstream gradually along the periphery of the tube and the wake vortex shed off continually at the lee-side of the USAF, i.e., wake vortex.

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Figure 11. Sketch of scour mechanism around USAF under random waves.

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Figure 12. Turbulence intensity: (a) Turbulence intensity of horseshoe vortex; (b) Turbulence intensity of wake vortex; (c) Turbulence intensity of accretion area.

The core of wake vortex is a negative pressure center, liking a vacuum cleaner [11,42]. Hence, the soil particles were swirled into the negative pressure core and carried away by wake vortex. At the same time, the onset of scour at rear side occurred. Finally, the wake vortex became downflow at the downside of USAF. As is shown in Figure 12, the turbulence intensity was low where the downflow occurred at lee-side, which means the turbulence energy may not be able to support the survival of wake vortex, leading to accretion happening. As mentioned in previous section, the formation of horseshoe vortex was dependent with adverse pressure gradient at upside of foundation. As shown in Figure 13, the evaluated range of pressure distribution is −15 m to 15 m in x direction. The t = 450 s and t = 1800 s indicate that the wave crest and trough arrived at the upside and lee-side of the foundation respectively, and the t = 350 s was neither the wave crest nor trough. The adverse gradient pressure reached the maximum value at t = 450 s corresponding to the wave crest phase. In this case, it’s helpful for the wave boundary separating fully from seabed, which leads to the formation of horseshoe vortex with high turbulence intensity. Therefore, the horseshoe vortex is responsible for the local scour between neighboring anchor branches at upside of USAF. What’s more, due to the combination of the horseshoe vortex and streamline compression, the maximum scour depth occurred at the upside of the USAF with an angle of about 45° corresponding to the wave propagating direction. This is consistent with the findings of Pang et al. [48] and Sumer et al. [1,15] in case of regular waves. At the wave trough phase (t = 1800 s), the pressure gradient became positive at upstream USAF edges, which hindered the separating of wave boundary from seabed. In the meantime, the flow reversal occurred (Figure 10) and the adverse gradient pressure appeared at downstream USAF edges, but the magnitude of adverse gradient pressure at lee-side was lower than the upstream gradient pressure under wave crest. In this way, the intensity of horseshoe vortex behind the USAF under wave trough was low, which explains the difference of scour depth at upstream and downstream, i.e., the scour asymmetry. In other words, the scour asymmetry at upside and downside of USAF was attributed to wave asymmetry for random waves, and the phenomenon became more evident for nonlinear waves [21]. Briefly speaking, the vortex system at wave crest phase was mainly related to the scour process around USAF under random waves.

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Figure 13. Pressure distribution around USAF.

4.3. Equilibrium Scour Depth

The KC number is a key parameter for horseshoe vortex emerging and evolving under waves. According to Equation (1), when pile diameter D is fixed, the KC depends on the maximum near-bed velocity Uwm and wave period T. For random waves, the Uwm can be denoted by the root-mean-square (RMS) value of near-bed velocity amplitude Uwm,rms or the significant value of near-bed velocity amplitude Uwm,s. The Uwm,rms and Uwm,s for all simulating cases of the present study are listed in Table 3 and Table 4. The T can be denoted by the mean up zero-crossing wave period Ta, peak wave period Tp, significant wave period Ts, the maximum wave period Tm, 1/10′th highest wave period Tn = 1/10 and 1/5′th highest wave period Tn = 1/5 for random waves, so the different combinations of Uwm and T will acquire different KC. The Table 3 and Table 4 list 12 types of KC, for example, the KCrms,s was calculated by Uwm,rms and Ts. Sumer and Fredsøe [16] conducted a series of wave flume experiments to investigate the scour depth around monopile under random waves, and found the equilibrium scour depth predicting equation (Equation (2)) for regular waves was applicable for random waves with KCrms,p. It should be noted that the Equation (2) is only suitable for KC > 6 under regular waves or KCrms,p > 6 under random waves.

Table 3. Uwm,rms and KC for case 1~9.

Table

Table 4. Uwm,s and KC for case 1~9.

Table

Raaijmakers and Rudolph [34] proposed the equilibrium scour depth predicting model (Equation (5)) around pile under waves, which is suitable for low KC. The format of Equation (5) is similar with the formula proposed by Breusers [54], which can predict the equilibrium scour depth around pile at different scour stages. In order to verify the applicability of Raaijmakers’s model for predicting the equilibrium scour depth around USAF under random waves, a validation of the equilibrium scour depth Seq between the present study and Raaijmakers’s equation was conducted. The position where the scour depth Seq was evaluated is the location of the maximum scour depth, and it was depicted in Figure 14. The Figure 15 displays the comparison of Seq with different KC between the present study and Raaijmakers’s model.

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Figure 14. Sketch of the position where the Seq was evaluated.

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Figure 15. Comparison of the equilibrium scour depth between the present model and the model of Raaijmakers and Rudolph [34]: (aKCrms,sKCrms,a; (bKCrms,pKCrms,m; (cKCrms,n = 1/10KCrms,n = 1/5; (dKCs,sKCs,a; (eKCs,pKCs,m; (fKCs,n = 1/10KCs,n = 1/5.

As shown in Figure 15, there is an error in predicting Seq between the present study and Raaijmakers’s model, and Raaijmakers’s model underestimates the results generally. Although the error exists, the varying trend of Seq with KC obtained from Raaijmakers’s model is consistent with the present study basically. What’s more, the error is minimum and the Raaijmakers’s model is of relatively high accuracy for predicting scour around USAF under random waves by using KCs,p. Based on this, a further revision was made to eliminate the error as much as possible, i.e., add the deviation value ∆S/D in the Raaijmakers’s model. The revised equilibrium scour depth predicting equation based on Raaijmakers’s model can be written as

S′eq/D=1.95[tanh(hD)](1−exp(−0.012KCs,p))+ΔS/D�eq′/�=1.95tanh(ℎ�)(1−exp(−0.012��s,p))+∆�/�(31)

As the Figure 16 shown, through trial-calculation, when ∆S/D = 0.05, the results calculated by Equation (31) show good agreement with the simulating results of the present study. The maximum error is about 18.2% and the engineering requirements have been met basically. In order to further verify the accuracy of the revised model for large KC (KCs,p > 4) under random waves, a validation between the revised model and the previous experimental results [21]. The experiment was conducted in a flume (50 m in length, 1.0 m in width and 1.3 m in height) with a slender vertical pile (D = 0.1 m) under random waves. The seabed is composed of 0.13 m deep layer of sand with d50 = 0.6 mm and the water depth is 0.5 m for all tests. The significant wave height is 0.12~0.21 m and the KCs,p is 5.52~11.38. The comparison between the predicting results by Equation (31) and the experimental results of Corvaro et al. [21] is shown in Figure 17. From Figure 17, the experimental data evenly distributes around the predicted results and the prediction accuracy is favorable when KCs,p < 8. However, the gap between the predicting results and experimental data becomes large and the Equation (31) overestimates the equilibrium scour depth to some extent when KCs,p > 8.

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Figure 16. Comparison of Seq between the simulating results and the predicting values by Equation (31).

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Figure 17. Comparison of Seq/D between the Experimental results of Corvaro et al. [21] and the predicting values by Equation (31).

In ocean environment, the waves are composed of a train of sinusoidal waves with different frequencies and amplitudes. The energy of constituent waves with very large and very small frequencies is relatively low, and the energy of waves is mainly concentrated in a certain range of moderate frequencies. Myrhaug and Rue [37] thought the 1/n’th highest wave was responsible for scour and proposed the stochastic model to predict the equilibrium scour depth around pile under random waves for full range of KC. Noteworthy is that the KC was denoted by KCrms,a in the stochastic model. To verify the application of the stochastic model for predicting scour depth around USAF, a validation between the simulating results of present study and predicting results by the stochastic model with n = 2,3,5,10,20,500 was carried out respectively.

As shown in Figure 18, compared with the simulating results, the stochastic model underestimates the equilibrium scour depth around USAF generally. Although the error exists, the varying trend of Seq with KCrms,a obtained from the stochastic model is consistent with the present study basically. What’s more, the gap between the predicting values by stochastic model and the simulating results decreases with the increase of n, but for large n, for example n = 500, the varying trend diverges between the predicting values and simulating results, meaning it’s not feasible only by increasing n in stochastic model to predict the equilibrium scour depth around USAF.

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Figure 18. Comparison of Seq between the simulating results and the predicting values by Equation (8).

The Figure 19 lists the deviation value ∆Seq/D′ between the predicting values and simulating results with different KCrms,a and n. Then, fitted the relationship between the ∆S′and n under different KCrms,a, and the fitting curve can be written by Equation (32). The revised stochastic model (Equation (33)) can be acquired by adding ∆Seq/D′ to Equation (8).

ΔSeq/D=0.052*exp(−n/6.566)+0.068∆�eq/�=0.052*exp(−�/6.566)+0.068(32)

S′eq¯/D=S′eq/D+0.052*exp(−n/6.566)+0.068�eq′¯/�=�eq′/�+0.052*exp(−�/6.566)+0.068(33)

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Figure 19. The fitting line between ∆S′and n.

The comparison between the predicting results by Equation (33) and the simulating results of present study is shown in Figure 20. According to the Figure 20, the varying trend of Seq with KCrms,a obtained from the stochastic model is consistent with the present study basically. Compared with predicting results by the stochastic model, the results calculated by Equation (33) is favorable. Moreover, comparison with simulating results indicates that the predicting results are the most favorable for n = 10, which is consistent with the findings of Myrhaug and Rue [37] for equilibrium scour depth predicting around slender pile in case of random waves.

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Figure 20. Comparison of Seq between the simulating results and the predicting values by Equation (33).

In order to further verify the accuracy of the Equation (33) for large KC (KCrms,a > 4) under random waves, a validation was conducted between the Equation (33) and the previous experimental results of Sumer and Fredsøe [16] and Corvaro et al. [21]. The details of experiments conducted by Corvaro et al. [21] were described in above section. Sumer and Fredsøe [16] investigated the local scour around pile under random waves. The experiments were conducted in a wave basin with a slender vertical pile (D = 0.032, 0.055 m). The seabed is composed of 0.14 m deep layer of sand with d50 = 0.2 mm and the water depth was maintained at 0.5 m. The JONSWAP wave spectrum was used and the KCrms,a was 5.29~16.95. The comparison between the predicting results by Equation (33) and the experimental results of Sumer and Fredsøe [16] and Corvaro et al. [21] are shown in Figure 21. From Figure 21, contrary to the case of low KCrms,a (KCrms,a < 4), the error between the predicting values and experimental results increases with decreasing of n for KCrms,a > 4. Therefore, the predicting results are the most favorable for n = 2 when KCrms,a > 4.

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Figure 21. Comparison of Seq between the experimental results of Sumer and Fredsøe [16] and Corvaro et al. [21] and the predicting values by Equation (33).

Noteworthy is that the present model was built according to prototype size, so the errors between the numerical results and experimental data of References [16,21] may be attribute to the scale effects. In laboratory experiments on scouring process, it is typically impossible to ensure a rigorous similarity of all physical parameters between the model and prototype structure, leading to the scale effects in the laboratory experiments. To avoid a cohesive behaviour, the bed material was not scaled geometrically according to model scale. As a consequence, the relatively large-scaled sediments sizes may result in the overestimation of bed load transport and underestimation of suspended load transport compared with field conditions. What’s more, the disproportional scaled sediment presumably lead to the difference of bed roughness between the model and prototype, and thus large influences for wave boundary layer on the seabed and scour process. Besides, according to Corvaro et al. [21] and Schendel et al. [55], the pile Reynolds numbers and Froude numbers both affect the scour depth for the condition of non fully developed turbulent flow in laboratory experiments.

4.4. Parametric Study

4.4.1. Influence of Froude Number

As described above, the set of foundation leads to the adverse pressure gradient appearing at upstream, leading to the wave boundary layer separating from seabed, then horseshoe vortex formatting and the horseshoe vortex are mainly responsible for scour around foundation (see Figure 22). The Froude number Fr is the key parameter to influence the scale and intensity of horseshoe vortex. The Fr under waves can be calculated by the following formula [42]

Fr=UwgD−−−√�r=�w��(34)

where Uw is the mean water particle velocity during 1/4 cycle of wave oscillation, obtained from the following formula. Noteworthy is that the root-mean-square (RMS) value of near-bed velocity amplitude Uwm,rms is used for calculating Uwm.

Uw=1T/4∫0T/4Uwmsin(t/T)dt=2πUwm�w=1�/4∫0�/4�wmsin(�/�)��=2��wm(35)

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Figure 22. Sketch of flow field at upstream USAF edges.

Tavouktsoglou et al. [25] proposed the following formula between Fr and the vertical location of the stagnation y

yh∝Fer�ℎ∝�r�(36)

where e is constant.

The Figure 23 displays the relationship between Seq/D and Fr of the present study. In order to compare with the simulating results, the experimental data of Corvaro et al. [21] was also depicted in Figure 23. As shown in Figure 23, the equilibrium scour depth appears a logarithmic increase as Fr increases and approaches the mathematical asymptotic value, which is also consistent with the experimental results of Corvaro et al. [21]. According to Figure 24, the adverse pressure gradient pressure at upstream USAF edges increases with the increase of Fr, which is benefit for the wave boundary layer separating from seabed, resulting in the high-intensity horseshoe vortex, hence, causing intensive scour around USAF. Based on the previous study of Tavouktsoglou et al. [25] for scour around pile under currents, the high Fr leads to the stagnation point is closer to the mean sea level for shallow water, causing the stronger downflow kinetic energy. As mentioned in previous section, the energy of downflow at upstream makes up the energy of the subsequent horseshoe vortex, so the stronger downflow kinetic energy results in the more intensive horseshoe vortex. Therefore, the higher Fr leads to the more intensive horseshoe vortex by influencing the position of stagnation point y presumably. Qi and Gao [19] carried out a series of flume tests to investigate the scour around pile under regular waves, and proposed the fitting formula between Seq/D and Fr as following

lg(Seq/D)=Aexp(B/Fr)+Clg(�eq/�)=�exp(�/�r)+�(37)

where AB and C are constant.

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Figure 23. The fitting curve between Seq/D and Fr.

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Figure 24. Sketch of adverse pressure gradient at upstream USAF edges.

Took the Equation (37) to fit the simulating results with A = −0.002, B = 0.686 and C = −0.808, and the results are shown in Figure 23. From Figure 23, the simulating results evenly distribute around the Equation (37) and the varying trend of Seq/D and Fr in present study is consistent with Equation (37) basically, meaning the Equation (37) is applicable to express the relationship of Seq/D with Fr around USAF under random waves.

4.4.2. Influence of Euler Number

The Euler number Eu is the influencing factor for the hydrodynamic field around foundation. The Eu under waves can be calculated by the following formula. The Eu can be represented by the Equation (38) for uniform cylinders [25]. The root-mean-square (RMS) value of near-bed velocity amplitude Um,rms is used for calculating Um.

Eu=U2mgD�u=�m2��(38)

where Um is depth-averaged flow velocity.

The Figure 25 displays the relationship between Seq/D and Eu of the present study. In order to compare with the simulating results, the experimental data of Sumer and Fredsøe [16] and Corvaro et al. [21] were also plotted in Figure 25. As shown in Figure 25, similar with the varying trend of Seq/D and Fr, the equilibrium scour depth appears a logarithmic increase as Eu increases and approaches the mathematical asymptotic value, which is also consistent with the experimental results of Sumer and Fredsøe [16] and Corvaro et al. [21]. According to Figure 24, the adverse pressure gradient pressure at upstream USAF edges increases with the increasing of Eu, which is benefit for the wave boundary layer separating from seabed, inducing the high-intensity horseshoe vortex, hence, causing intensive scour around USAF.

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Figure 25. The fitting curve between Seq/D and Eu.

Therefore, the variation of Fr and Eu reflect the magnitude of adverse pressure gradient pressure at upstream. Given that, the Equation (37) also was used to fit the simulating results with A = 8.875, B = 0.078 and C = −9.601, and the results are shown in Figure 25. From Figure 25, the simulating results evenly distribute around the Equation (37) and the varying trend of Seq/D and Eu in present study is consistent with Equation (37) basically, meaning the Equation (37) is also applicable to express the relationship of Seq/D with Eu around USAF under random waves. Additionally, according to the above description of Fr, it can be inferred that the higher Fr and Eu both lead to the more intensive horseshoe vortex by influencing the position of stagnation point y presumably.

5. Conclusions

A series of numerical models were established to investigate the local scour around umbrella suction anchor foundation (USAF) under random waves. The numerical model was validated for hydrodynamic and morphology parameters by comparing with the experimental data of Khosronejad et al. [52], Petersen et al. [17], Sumer and Fredsøe [16] and Schendel et al. [22]. Based on the simulating results, the scour evolution and scour mechanisms around USAF under random waves were analyzed respectively. Two revised models were proposed according to the model of Raaijmakers and Rudolph [34] and the stochastic model developed by Myrhaug and Rue [37] to predict the equilibrium scour depth around USAF under random waves. Finally, a parametric study was carried out with the present model to study the effects of the Froude number Fr and Euler number Eu to the equilibrium scour depth around USAF under random waves. The main conclusions can be described as follows.(1)

The packed sediment scour model and the RNG k−ε turbulence model were used to simulate the sand particles transport processes and the flow field around UASF respectively. The scour evolution obtained by the present model agrees well with the experimental results of Khosronejad et al. [52], Petersen et al. [17], Sumer and Fredsøe [16] and Schendel et al. [22], which indicates that the present model is accurate and reasonable for depicting the scour morphology around UASF under random waves.(2)

The vortex system at wave crest phase is mainly related to the scour process around USAF under random waves. The maximum scour depth appeared at the lee-side of the USAF at the initial stage (t < 1200 s). Subsequently, when t > 2400 s, the location of the maximum scour depth shifted to the upside of the USAF at an angle of about 45° with respect to the wave propagating direction.(3)

The error is negligible and the Raaijmakers’s model is of relatively high accuracy for predicting scour around USAF under random waves when KC is calculated by KCs,p. Given that, a further revision model (Equation (31)) was proposed according to Raaijmakers’s model to predict the equilibrium scour depth around USAF under random waves and it shows good agreement with the simulating results of the present study when KCs,p < 8.(4)

Another further revision model (Equation (33)) was proposed according to the stochastic model established by Myrhaug and Rue [37] to predict the equilibrium scour depth around USAF under random waves, and the predicting results are the most favorable for n = 10 when KCrms,a < 4. However, contrary to the case of low KCrms,a, the predicting results are the most favorable for n = 2 when KCrms,a > 4 by the comparison with experimental results of Sumer and Fredsøe [16] and Corvaro et al. [21].(5)

The same formula (Equation (37)) is applicable to express the relationship of Seq/D with Eu or Fr, and it can be inferred that the higher Fr and Eu both lead to the more intensive horseshoe vortex and larger Seq.

Author Contributions

Conceptualization, H.L. (Hongjun Liu); Data curation, R.H. and P.Y.; Formal analysis, X.W. and H.L. (Hao Leng); Funding acquisition, X.W.; Writing—original draft, R.H. and P.Y.; Writing—review & editing, X.W. and H.L. (Hao Leng); The final manuscript has been approved by all the authors. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the Fundamental Research Funds for the Central Universities (grant number 202061027) and the National Natural Science Foundation of China (grant number 41572247).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The data presented in this study are available on request from the corresponding author.

Conflicts of Interest

The authors declare no conflict of interest.

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Hu, R.; Liu, H.; Leng, H.; Yu, P.; Wang, X. Scour Characteristics and Equilibrium Scour Depth Prediction around Umbrella Suction Anchor Foundation under Random Waves. J. Mar. Sci. Eng. 20219, 886. https://doi.org/10.3390/jmse9080886

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Hu R, Liu H, Leng H, Yu P, Wang X. Scour Characteristics and Equilibrium Scour Depth Prediction around Umbrella Suction Anchor Foundation under Random Waves. Journal of Marine Science and Engineering. 2021; 9(8):886. https://doi.org/10.3390/jmse9080886Chicago/Turabian Style

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Fig. 1- Schematic of the general pattern of flow and aeration process in the aerators

2상 유동 해석을 통한 슈트 폭기 시스템 효율에 대한 램프 각도의 영향 조사

Investigation of the Effect of Ramp Angle on Chute Aeration System Efficiency by Two-Phase Flow Analysis

Authors

1 Associate Professor, Civil Engineering Department, Jundi-Shapur University of Technology, Dezful, Iran

2 Instructor in Civil Engineering Department Jundi-Shapur University of Technology, Dezful,Iran.

 10.22055/JISE.2021.37743.1980

Abstract

Flow aeration in chute spillway is one of the most effective and economic ways to prevent cavitation damage. Surface damage is significantly reduced when very small values of air are scattered in a water prism. A structure known as an aerator may be used for this purpose. Besides, ramp angle is one of the factors influencing aerator efficiency. In this research, the value of air entraining the flow through the Jarreh Dam’s spillway at the ramp angles of 6, 8 and 10 degrees, as three different scenarios, was simulated using the Flow-3D software. In order to validate the results of the inlet air into the flowing fluid at a ramp angle of 6 degrees, the observational results of the dam spillway physical model from the laboratory of TAMAB Company in Iran were used. According to the results, raising the ramp angle increases the inlet air to the water jet nappe, and a ten-degree ramp angle provides the best aeration efficiency. The Flow-3D model can also simulate the two-phase water-air flow on spillways, according to the results.

슈트 여수로의 흐름 폭기는 캐비테이션 손상을 방지하는 가장 효과적이고 경제적인 방법 중 하나입니다. 수중 프리즘에 아주 작은 양의 공기가 흩어지면 표면 손상이 크게 줄어듭니다. 이를 위해 폭기 장치로 알려진 구조를 사용할 수 있습니다. 또한, 램프 각도는 폭기 효율에 영향을 미치는 요인 중 하나입니다. 이 연구에서는 FLOW-3D 소프트웨어를 사용하여 3가지 다른 시나리오인 6, 8 및 10도의 램프 각도에서 Jarreh 댐의 방수로를 통해 흐름을 동반하는 공기의 값을 시뮬레이션했습니다. 6도의 경사각에서 유동 유체로 유입되는 공기의 결과를 검증하기 위해이란 TAMAB Company의 실험실에서 댐 방수로 물리적 모델의 관찰 결과를 사용했습니다. 결과에 따르면 램프 각도를 높이면 워터제트 기저귀로 유입되는 공기가 증가하고 10도 램프 각도는 최고의 폭기 효율을 제공합니다. Flow-3D 모델은 결과에 따라 여수로의 2단계 물-공기 흐름을 시뮬레이션할 수도 있습니다.

Keywords

Fig. 1- Schematic of the general pattern of flow and aeration process in the aerators
Fig. 1- Schematic of the general pattern of flow and aeration process in the aerators
(a) The full-scale map of the Jarreh spillway’s plan and profile.
(a) The full-scale map of the Jarreh spillway’s plan and profile.
Fig. 2- Experimental setup (Shamloo et al., 2012)
Fig. 2- Experimental setup (Shamloo et al., 2012)

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Fig. 2- Experimental setup (Shamloo et al., 2012)

2상 유동 해석을 통한 슈트 폭기 시스템 효율에 대한 램프 각도의 영향 조사

1 Associate Professor, Civil Engineering Department, Jundi-Shapur University of Technology, Dezful, Iran

2 Instructor in Civil Engineering Department Jundi-Shapur University of Technology, Dezful,Iran.

 10.22055/JISE.2021.37743.1980

Abstract

슈트 여수로의 흐름 폭기는 캐비테이션 손상을 방지하는 가장 효과적이고 경제적인 방법 중 하나입니다. 수중 프리즘에 아주 작은 양의 공기가 흩어지면 표면 손상이 크게 줄어듭니다. 이를 위해 폭기 장치로 알려진 구조를 사용할 수 있습니다. 또한, 램프 각도는 폭기 효율에 영향을 미치는 요인 중 하나입니다. 이 연구에서는 Flow-3D 소프트웨어를 사용하여 3가지 다른 시나리오인 6, 8 및 10도의 램프 각도에서 Jarreh 댐의 방수로를 통해 흐름을 동반하는 공기의 값을 시뮬레이션했습니다. 6도의 경사각에서 유동 유체로 유입되는 공기의 결과를 검증하기 위해이란 TAMAB Company의 실험실에서 댐 방수로 물리적 모델의 관찰 결과를 사용했습니다. 결과에 따르면 램프 각도를 높이면 워터제트 기저귀로 유입되는 공기가 증가하고 10도 램프 각도는 최고의 폭기 효율을 제공합니다. Flow-3D 모델은 결과에 따라 여수로의 2단계 물-공기 흐름을 시뮬레이션할 수도 있습니다.

Flow aeration in chute spillway is one of the most effective and economic ways to prevent cavitation damage. Surface damage is significantly reduced when very small values of air are scattered in a water prism. A structure known as an aerator may be used for this purpose. Besides, ramp angle is one of the factors influencing aerator efficiency. In this research, the value of air entraining the flow through the Jarreh Dam’s spillway at the ramp angles of 6, 8 and 10 degrees, as three different scenarios, was simulated using the Flow-3D software. In order to validate the results of the inlet air into the flowing fluid at a ramp angle of 6 degrees, the observational results of the dam spillway physical model from the laboratory of TAMAB Company in Iran were used. According to the results, raising the ramp angle increases the inlet air to the water jet nappe, and a ten-degree ramp angle provides the best aeration efficiency. The Flow-3D model can also simulate the two-phase water-air flow on spillways, according to the results.

Fig. 1- Schematic of the general pattern of flow and aeration process in the aerators
Fig. 1- Schematic of the general pattern of flow and aeration process in the aerators
Fig. 2- Experimental setup (Shamloo et al., 2012)
Fig. 2- Experimental setup (Shamloo et al., 2012)
Fig. 3- Results of numerical model validation in determining a) mean flow depth, b) mean velocity, and c) static pressure in various discharges vs (Shamloo et al., 2012) research under a 6 degree ramp angle
Fig. 3- Results of numerical model validation in determining a) mean flow depth, b) mean velocity, and c) static pressure in various discharges vs (Shamloo et al., 2012) research under a 6 degree ramp angle
Fig. 4- Location of data extraction stations after aeration on a scale model of 1:50
Fig. 4- Location of data extraction stations after aeration on a scale model of 1:50
Fig.7- Changes in cavitation index in different discharges with changes in ramp angle: a) 6 degrees, b) 8 degrees and c) 10 degrees
Fig.7- Changes in cavitation index in different discharges with changes in ramp angle: a) 6 degrees, b) 8 degrees and c) 10 degrees

Keywords

Aeration system Ramp angle Aeration coefficient Two-phase flow Flow-3D model

참고문헌

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2- Bayon, A., Toro, JP, Bombardelli, FA, Matos, J., & López-Jiménez, PA(2018). VOF 기술, 난류 모델 및 이산화 방식이 계단식 배수로에서 폭기되지 않은 스키밍 흐름의 수치 시뮬레이션에 미치는 영향. 수력 환경 연구 저널 , 19 , 137–149. https://doi.org/10.1016/j.jher.2017.10.002

3- Brethour, JM, & Hirt, CW (2009). 2성분 흐름에 대한 드리프트 모델. Flow Science, Inc. , FSI – 09 – TN83Rev , 1–7.

4- Chanson, H. (1989). 공기 유입 및 폭기 장치 연구. 수력학 연구 저널 , 27 (3), 301–319. https://doi.org/10.1080/00221688909499166

5- Dong, Z., Wang, J., Vetsch, DF, Boes, RM, & Tan, G. (2019). 매우 높은 단위 배출에서 X자형 플레어링 게이트 교각 뒤의 계단식 배수로에서 공기-물 2상 흐름의 수치 시뮬레이션. 물(스위스) , 11 (10). https://doi.org/10.3390/w11101956

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Computational Fluid Dynamics, 온실

CFD 사용: 유압 구조 및 농업에서의 응용

USO DE CFD COMO HERRAMIENTA PARA LA MODELACIÓN Y  PREDICCIÓN NUMÉRICA DE LOS FLUIDOS: APLICACIONES EN  ESTRUCTURAS HIDRÁULICAS Y AGRICULTURA

Cruz Ernesto Aguilar-Rodriguez1*; Candido Ramirez-Ruiz2; Erick Dante Mattos Villarroel3 

1Tecnológico Nacional de México/ITS de Los Reyes. Carretera Los Reyes-Jacona, Col. Libertad. 60300.  Los Reyes de Salgado, Michoacán. México. 

ernesto.ar@losreyes.tecnm.mx – 3541013901 (*Autor de correspondencia) 

2Instituto de Ciencias Aplicadas y Tecnología, UNAM. Cto. Exterior S/N, C.U., Coyoacán, 04510, Ciudad  de México. México.  3Riego y Drenaje. Instituto Mexicano de Tecnología del Agua. Paseo Cuauhnáhuac 8532, Progreso,  Jiutepec, Morelos, C.P. 62550. México.

Abstract

공학에서 유체의 거동은 설명하기에 광범위하고 복잡한 과정이며, 유체역학은 유체의 거동을 지배하는 방정식을 통해 유체 역학 현상을 분석할 수 있는 과학 분야이지만 이러한 방정식에는 전체 솔루션이 없습니다. . 전산유체역학(Computational Fluid Dynamics, 이하 CFD)은 수치적 기법을 통해 방정식의 해에 접근할 수 있는 도구로, 신뢰할 수 있는 계산 모델을 얻기 위해서는 물리적 모델의 실험 데이터로 평가해야 합니다. 수력구조물에서 선형 및 미로형 여수로에서 시뮬레이션을 수행하고 배출 시트의 거동과 현재의 폭기 조건을 분석했습니다. 침강기에서 유체의 특성화를 수행하고 필요한 특성에 따라 사체적, 피스톤 또는 혼합의 분수를 수정하는 것이 가능합니다. 농업에서는 온실 환경을 특성화하고 환경에 대한 재료의 디자인, 방향 및 유형 간의 관계를 찾는 데 사용할 수 있습니다. 발견된 가장 중요한 결과 중 온실의 길이와 설계가 환기율에 미칠 수 있는 영향으로 온실의 길이는 높이의 6배 미만인 것이 권장됩니다.

키워드: Computational Fluid Dynamics, 온실,

Spillway, Settler 기사: COMEII-21048 소개 

CFD는 유체 운동 문제에 대한 수치적 솔루션을 얻어 수리학적 현상을 더 잘 이해할 수 있게 함으로써 공간 시각화를 가능하게 하는 수치 도구입니다. 예를 들어, 수력 공학에서 벤츄리(Xu, Gao, Zhao, & Wang, 2014) 워터 펌핑(ȘCHEAUA, 2016) 또는 개방 채널 적용( Wu et 알., 2000). 

문헌 검토는 실험 연구에서 검증된 배수로의 흐름 거동에 대한 수리학적 분석을 위한 CFD 도구의 효율성을 보여줍니다. 이 검토는 둑의 흐름 거동에 대한 수리학적 분석을 위한 CFD의 효율성을 보여줍니다. Crookston et al. (2012)는 미로 여수로에 대해 Flow 3D로 테스트를 수행했으며, 배출 계수의 결과는 3%에서 7%까지 다양한 오류로 실험적으로 얻은 결과로 허용 가능했으며 연구 결과 측면에 저압 영역이 있음을 발견했습니다. 익사 방식으로 작업할 때 위어의 벽. Zuhair(2013)는 수치 모델링 결과를 Mandali weir 원형의 실험 데이터와 비교했습니다.  

최근 연구에서는 다양한 난류 모델을 사용하여 CFD를 적용할 가능성이 있음을 보여주었습니다. 그리고 일부만이 음용수 처리를 위한 침적자의 사례 연구를 제시했으며, 다른 설계 변수 중에서 기하학적인 대안, 수온 변화 등을 제안했습니다. 따라서 기술 개발로 인해 설계 엔지니어가 유체 거동을 분석하는 데 CFD 도구를 점점 더 많이 사용하게 되었습니다. 

보호 농업에서 CFD는 온실 환경을 모델링하고 보조 냉방 또는 난방 시스템을 통해 온실의 미기후 관리를 위한 전략을 제안하는 데 사용되는 기술이었습니다(Aguilar Rodríguez et al., 2020).  

2D 및 3D CFD 모델을 사용한 본격적인 온실 시뮬레이션은 태양 복사 모델과 현열 및 잠열 교환 하위 모델의 통합을 통해 온실의 미기후 분포를 연구하는 데 사용되었습니다(Majdoubi, Boulard, Fatnassi, & Bouirden, 2009). 마찬가지로 이 모델을 사용하여 온실 설계(Sethi, 2009), 덮개 재료(Baxevanou, Fidaros, Bartzanas, & Kittas, 2018), 시간, 연중 계절( Tong, Christopher, Li, & Wang, 2013), 환기 유형 및 구성(Bartzanas, Boulard, & Kittas, 2004). 

CFD 거래 프로그램은 사용자 친화적인 플랫폼으로 설계되어 결과를 쉽게 관리하고 이해할 수 있습니다.  

Figura 1. Distribución de presiones y velocidades en un vertedor de pared delgada.
Figura 2. Perfiles de velocidad y presión en la cresta vertedora.
Figura 3. Condiciones de aireación en vertedor tipo laberinto. (A)lámina adherida a la pared del
vertedor, (B) aireado, (C) parcialmente aireado, (D) ahogado.
Figura 4. Realización de prueba de riego.
Figura 5. Efecto de la posición y dirección de los calefactores en un invernadero a 2 m del suelo.
Figura 5. Efecto de la posición y dirección de los calefactores en un invernadero a 2 m del suelo.
Figura 6. Indicadores ambientales para medir el confort ambiental de los cultivos.
Figura 6. Indicadores ambientales para medir el confort ambiental de los cultivos.
Figura 7. Líneas de corriente dentro del sedimentador experimental en estado estacionario  (Ramirez-Ruiz, 2019).
Figura 7. Líneas de corriente dentro del sedimentador experimental en estado estacionario (Ramirez-Ruiz, 2019).

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CFD Simulations of Conical Central Baffle Flumes | Journal of Irrigation and Drainage Engineering | Vol 148, No 2

원추형 중앙 배플 수로의 CFD 시뮬레이션

CFD Simulations of Conical Central Baffle Flumes

Abstract

Ankur KapoorAniruddha D. Ghare; and Avinash M. Badar

원추형 중앙 배플 수로는 개방 채널에서 임시 유량 측정을 위한 효과적인 솔루션을 제공합니다. 

원추형 중앙 배플 수로는 원뿔 모양의 장애물 또는 열린 수로의 중심에서 수직으로 향하는 중앙 배플로 구성됩니다. 본 연구에서, 원추형 중앙 배플 수로를 사용하여 개방 채널에서 유량 측정을 위해 이전에 개발된 배출 예측 모델은 더 넓은 적용 범위를 커버하기 위해 직사각형 및 사다리꼴 채널에서 사용하기 위해 실험적으로 재 보정되었습니다. 

제안된 보정 방정식은 FLOW-3D를 사용한 전산유체역학(CFD) 시뮬레이션 결과를 사용하여 확장된 범위의 흐름 및 기하학적 매개변수에 대해 검증되었습니다. 

시뮬레이션 연구는 두 단계로 수행됩니다. 첫 번째 단계는 시뮬레이션의 수면 프로파일과 동일한 배출 및 흐름 조건에 대한 실험 흐름을 비교하여 설정한 정의된 시뮬레이션 문제의 검증입니다. 

두 번째 단계는 무차원 방전 및 측면 경사(중1= 0중1=0, 0.50, 1.00 및 1.50). 80% 미만의 수중에서 방전 예측의 오류는 평균값이 거의 3%로 항상 10% 미만인 것으로 나타났습니다. 

CFD 분석 결과에 따르면 보정된 배출 예측 모델의 사용은 수중 한계 80%까지 권장되었으며, 그 이상에서는 오차가 10% 이상인 것으로 나타났습니다.

Conical central baffle flumes present an effective solution for temporary flow measurements in open channels. A conical central baffle flume consists of a cone-shaped obstruction, or a central baffle, oriented vertically at the center of an open channel. In the present study, a previously developed discharge prediction model for flow measurements in open channels using the conical central baffle flumes has been experimentally recalibrated for use in rectangular and trapezoidal channels to cover a wider application range. The proposed calibration equation has been validated for an extended range of flow and geometrical parameters using the results of computational fluid dynamics (CFD) simulations using Flow-3D. The simulation studies are carried out in two steps. The first step is the validation of the defined simulation problem set up by comparing the water surface profiles of the simulation and experiment flows for the same discharge and flow conditions. The second step is the validation of the proposed discharge prediction model for the extended range (0–0.50) of the dimensionless discharge and side slopes (m1=0m1=0, 0.50, 1.00, and 1.50). It is found that for submergence less than 80%, the error in discharge prediction is always less than 10% with a mean value of nearly 3%. Based on the results of the CFD analysis, the use of the calibrated discharge prediction model has been recommended up to a submergence limit of 80%, beyond which the errors are found to be greater than 10%.

ASCE Library CFD Simulations of Conical Central Baffle Flumes | Journal of Irrigation and Drainage Engineering | Vol 148, No 2
ASCE Library CFD Simulations of Conical Central Baffle Flumes | Journal of Irrigation and Drainage Engineering | Vol 148, No 2
CFD Simulations of Conical Central Baffle Flumes | Journal of Irrigation and Drainage Engineering | Vol 148, No 2
CFD Simulations of Conical Central Baffle Flumes | Journal of Irrigation and Drainage Engineering | Vol 148, No 2
CFD Simulations of Conical Central Baffle Flumes | Journal of Irrigation and Drainage Engineering | Vol 148, No 2
CFD Simulations of Conical Central Baffle Flumes | Journal of Irrigation and Drainage Engineering | Vol 148, No 2
Channel Flow Measurement Using Portable Conical Central Baffle | Journal of Irrigation and Drainage Engineering | Vol 145, No 11
Channel Flow Measurement Using Portable Conical Central Baffle | Journal of Irrigation and Drainage Engineering | Vol 145, No 11
여수로 방류에 따른 여수로 바닥 슬래브의 손상 메커니즘 검토

여수로 방류에 따른 여수로 바닥 슬래브의 손상 메커니즘 검토

Examinations of Damage Mechanism on the Chuteway Slabs of Spillway under Various Flow Conditions

  • Yoo, Hyung Ju ;
  • Shin, Dong-Hoon ;
  • Lee, Seung Oh
  • 유형주 (홍익대학교 공과대학 건설환경공학과) ;
  • 신동훈 (K-water연구원 물인프라안전연구소) ;
  • 이승오 (홍익대학교 공과대학 건설환경공학과)
  • Published : 2021.06.03

Abstract

최근 기후변화로 인한 집중호우의 영향으로 홍수 시 댐으로의 유입량이 설계 당시보다 증가하여 댐의 안전성 확보가 필요하다(감사원, 2003). 이에 건설교통부(2003)는 기후변화와 댐 노후화에 대비하여 치수능력증대사업을 추진하여 댐의 홍수배제능력을 확보하였고, 환경부(2020)에서는 40년 이상 경과된 댐을 대상으로 스마트 안전관리체계 구축을 통한 선제적 보수보강, 성능개선 및 자산관리로 댐의 장수명화를 목적으로 댐의 국가안전대진단을 추진하고 있다. 이에 본 연구에서는 댐 시설(여수로)의 노후도 평가 시 활용 될 수 있는 여수로 표면손상 원인규명에 대하여 3차원 수치모형(FLOW-3D 및 COMSOL Multiphysics)을 통해 검토하고자 한다. 연구대상 댐은 𐩒𐩒댐으로 지형 및 여수로를 구축하였으며, 계획방류량(200년 빈도) 및 최대방류량(PMF) 조건에서 모의를 수행하였다. 수치모의 계산의 정확도 검토를 위하여 Baffle의 설치를 통하여 시간에 따른 유량의 변화를 설계 값과 비교하였고 오차가 1.0% 이내를 만족하는 것을 확인하였다. 여수로 표면손상의 다양한 원인 중 기존연구(USBR, 2019)를 통하여 공동침식(Cavitation Erosion) 및 수력잭킹(Hydraulic Jacking)에 초점을 두었으며 방류조건 별 공동지수(Cavitation Index)산정을 통하여 공동침식 위험 구간을 확인하였다. 이음부의 균열 및 공동으로 인한 표층부 콘크리트의 탈락현상을 가속화시키는 수력잭킹 검토를 위하여 국부모형을 구축하였고 음압력(Negative Pressure), 정체압력(Stagnation Pressure), 양압력(Uplift Pressure)의 분포를 확인하였다. 최종적으로 COMSOL Multiphysics를 통하여 압력분포에 따른 구조해석을 수행하여 폰 미세스(Von Mises) 등가응력 및 변위를 검토하여 콘크리트의 탈락가능성을 확인하였다. 본 연구는 여수로 공동부 및 균열부에서의 손상메커니즘을 확인할 수 있는 기초적인 연구이지만 향후에는 다양한 지형조건 및 흐름조건에서의 압력분포 분석 및 유체-구조물 상호작용(Fluid-Structure Interaction, FSI)모의를 수행한다면 구조물 노후도 및 잔존수명 평가에 필요한 손상한계함수 도출이 가능할 것으로 기대된다.

Keywords

Figure 1- The experimental model [17]

와류형 우수 저류지의 수치 모델링에 대한 난류 슈미트 수의 영향 조사

Investigation of the Turbulent Schmidt Number Effects On Numerical Modelling Of Vortex-Type Stormwater Retention Ponds

S. M. Yamini1; H. Shamloo2; S. H. Ghafari3
1M.Eng., Dep. of Civil Engineering K.N. Toosi University of Technology, Valiasr St., Tehran, Iran.
smyamini@alumni.kntu.ac.ir
2Associate Professor, Dep. of Civil Engineering K.N. Toosi University of Technology, Valiasr St., Tehran, Iran.
hshamloo@kntu.ac.ir
3Ph.D., Dep. of Civil Engineering Univ. of Tehran, Enqelab St., Tehran, Iran. sarvenazghafari@ut.ac.ir

Abstract

정확하고 신뢰할 수 있는 CFD 모델링 결과를 얻는 것은 이러한 시뮬레이션에서 입력의 중요성 때문에 종종 정밀 조사의 대상입니다.

난류 모델링이 RANS(Reynolds-Averaged Navier-Stokes) 방정식을 기반으로 하는 경우 난류 스칼라 전송을 추정하려면 난류 흐름에서 질량 1에 대한 운동량 확산의 비율로 정의되는 난류 슈미트 수(Sct)의 정의가 필요합니다.

그러나 이 매개변수는 난류 흐름의 속성이므로 보편적인 값이 허용되지 않았습니다. 우수 저류지의 수치 연구에서 적절한 Sct를 설정하는 실제 역할은 수력 효율의 평가가 추적자 테스트의 출력 질량 농도를 기반으로 하기 때문에 가장 중요합니다.

본 연구에서는 FLOW-3D를 사용하여 와류형 우수 저류지의 여러 수치 시뮬레이션을 체계적으로 수행했습니다. 다양한 난류 슈미트 수의 범위는 메쉬 감도를 조사하기 위해 다른 수의 계산 셀에 의해 수행된 수치 시뮬레이션에 도입되었습니다.

또한 사용자 정의 또는 자동 계산 값으로 최대 난류 혼합 길이의 영향을 평가했습니다. 이 연구의 결과는 실험 결과와 밀접한 일치를 제공하는 Sct= 0.625와 함께 수리학적 직경의 7%와 동일한 최대 난류 혼합 길이의 일정한 값을 갖는 확립된 수치 모델입니다.

특히 수치적 무차원 RDT 곡선의 피크 값은 극적으로 감소하여 실험 결과와 거의 일치했습니다. 이것은 FLOW-3D가 난류 유동의 와류형 물리학에서 질량 확산도를 적절하게 예측하는 상당한 능력을 가지고 있다는 결론을 내립니다.

– Achieving accurate and reliable CFD modelling results often is the subject of scrutiny because of the importance of the inputs in those simulations. If turbulence modelling is based on Reynolds-Averaged Navier-Stokes (RANS) equations, estimating the turbulent scalar transport requires the definition of the turbulent Schmidt number (Sct), defined as the ratio of momentum diffusivity to mass one in a turbulent flow. However, no universal value has been accepted for this parameter as it is a property of turbulent flows.

The practical role of establishing a suitable Sct in numerical studies of stormwater retention ponds is of the utmost importance because the assessment of the hydraulic efficiency of them is based on output mass concentration of tracer tests. In this study, several numerical simulations of a vortex-type stormwater retention pond were systematically carried out using FLOW-3D. A range of various turbulent Schmidt numbers were introduced in numerical simulations performed by different number of computational cells to investigate mesh sensitivity.

Moreover, the effects of maximum turbulent mixing length as a user-defined or automatically computed value were assessed. The outcome of this study is an established numerical model with a constant value of maximum turbulent mixing length equal to 7% of the hydraulic diameter along with Sct= 0.625 which provides a close agreement with experimental results.

Noticeably, the peak values of numerical dimensionless RDT curves are dramatically decreased, resulted in a close match with experimental results. This concludes that FLOW-3D has a considerable ability to appropriately predict mass diffusivity in vortex-type physics of turbulent flows.

Keywords:

turbulent Schmidt number – maximum turbulent mixing length – CFD – mesh sensitivity – vortex-type
stormwater retention pond – environmental fluid mechanics

Figure 1- The experimental model [17]
Figure 1- The experimental model [17]
Figure 2- Schematic of boundary conditions in the numerical model
Figure 2- Schematic of boundary conditions in the numerical model
Figure 3- Positioning of mesh blocks
Figure 3- Positioning of mesh blocks

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Fig. 11. Velocity vectors along x-direction through the center of the box culvert for B0, B30, B50, and B70 respectively.

Numerical investigation of scour characteristics downstream of blocked culverts

막힌 암거 하류의 세굴 특성 수치 조사

NesreenTahabMaged M.El-FekyaAtef A.El-SaiadaIsmailFathya
aDepartment of Water and Water Structures Engineering, Faculty of Engineering, Zagazig University, Zagazig 44519, Egypt
bLab Manager, Faculty of Engineering, Zagazig University, Zagazig 44519, Egypt

Abstract

횡단 구조물을 통한 막힘은 안정성을 위협하는 위험한 문제 중 하나입니다. 암거의 막힘 형상 및 하류 세굴 특성에 미치는 영향에 관한 연구는 거의 없습니다.

이 연구의 목적은 수면과 세굴 모두에서 상자 암거를 통한 막힘의 작용을 수치적으로 논의하는 것입니다. 이를 위해 FLOW 3D v11.1.0을 사용하여 퇴적물 수송 모델을 조사했습니다.

상자 암거를 통한 다양한 차단 비율이 연구되었습니다. FLOW 3D 모델은 실험 데이터로 보정되었습니다. 결과는 FLOW 3D 프로그램이 세굴 다운스트림 상자 암거를 정확하게 시뮬레이션할 수 있음을 나타냅니다.

막힌 경우에 대한 속도 분포, 최대 세굴 깊이 및 수심을 플롯하고 비차단된 사례(기본 사례)와 비교했습니다.

그 결과 암거 높이의 70% 차단율은 상류의 수심을 암거 높이의 2.3배 증가시키고 평균 유속은 기본 경우보다 3배 더 증가시키는 것으로 입증되었다. 막힘 비율의 함수로 상대 최대 세굴 깊이를 추정하는 방정식이 만들어졌습니다.

Blockage through crossing structures is one of the dangerous problems that threaten its stability. There are few researches concerned with blockage shape in culverts and its effect on characteristics of scour downstream it.

The study’s purpose is to discuss the action of blockage through box culvert on both water surface and scour numerically. A sediment transport model has been investigated for this purpose using FLOW 3D v11.1.0. Different ratios of blockage through box culvert have been studied. The FLOW 3D model was calibrated with experimental data.

The results present that the FLOW 3D program was capable to simulate accurately the scour downstream box culvert. The velocity distribution, maximum scour depth and water depths for blocked cases have been plotted and compared with the non-blocked case (base case).

The results proved that the blockage ratio 70% of culvert height makes the water depth upstream increases by 2.3 times of culvert height and mean velocity increases by 3 times more than in the base case. An equation has been created to estimate the relative maximum scour depth as a function of blockage ratio.

1. Introduction

Local scour is the removal of granular bed material by the action of hydrodynamic forces. As the depth of scour hole increases, the stability of the foundation of the structure may be endangered, with a consequent risk of damage and failure [1]. So the prediction and control of scour is considered to be very important for protecting the water structures from failure. Most previous studies were designed to study the different factors that impact on scour and their relationship with scour hole dimensions like fluid characteristics, flow conditions, bed properties, and culvert geometry. Many previous researches studied the effect of flow rate on scour hole by information Froude number or modified Froude number [2][3][4][5][6]. Cesar Mendoza [6] found a good correlation between the scour depth and the discharge Intensity (Qg−.5D−2.5). Breusers and Raudkiv [7] used shear velocity in the outlet-scour prediction procedure. Ali and Lim [8] used the densimetric Froude number in estimation of the scour depth [1][8][9][10][11][12][13][14]. “The densimetric Froude number presents the ratio of the tractive force on sediment particle to the submerged specific weight of the sediment” [15](1)Fd=uρsρ-1gD50

Ali and Lim [8] pointed to the consequence of tailwater depth on scour behavior [1][2][8][13]. Abida and Townsend [2] indicated that the maximum depth of local scour downstream culvert was varying with the tailwater depth in three ways: first, for very shallow tailwater depths, local scouring decreases with a decrease in tailwater depth; second, when the ratio of tailwater depth to culvert height ranged between 0.2 and 0.7, the scour depth increases with decreasing tailwater depth; and third for a submerged outlet condition. The tailwater depth has only a marginal effect on the maximum depth of scour [2]. Ruff et al. [16] observed that for materials having similar mean grain sizes (d50) but different standard deviations (σ). As (σ) increased, the maximum scour hole depth decreased. Abt et al. [4] mentioned to role of soil type of maximum scour depth. It was noticed that local scour was more dangerous for uniform sands than for well-graded mixtures [1][2][4][9][17][18]. Abt et al [3][19] studied the culvert shape effect on scour hole. The results evidenced that the culvert shape has a limited effect on outlet scour. Under equivalent discharge conditions, it was noted that a square culvert with height equal to the diameter of a circular culvert would reduce scour [16][20]. The scour hole dimension was also effected by the culvert slope. Abt et al. [3][21] showed that the culvert slope is a key element in estimating the culvert flow velocity, the discharge capacity, and sediment transport capability. Abt et al. [21][22] tested experimentally culvert drop height effect on maximum scour depth. It was observed that as the drop height was increasing, the depth of scour was also increasing. From the previous studies, it could have noticed that the most scour prediction formula downstream unblocked culvert was the function of densimetric Froude number, soil properties (d50, σ), tailwater depth and culvert opening size. Blockage is the phenomenon of plugging water structures due to the movement of water flow loaded with sediment and debris. Water structures blockage has a bad effect on water flow where it causes increasing of upstream water level that may cause flooding around the structure and increase of scour rate downstream structures [23][24]. The blockage phenomenon through was studied experimentally and numerical [15][25][26][27][28][29][30][31][32][33]. Jaeger and Lucke [33] studied the debris transport behavior in a natural channel in Australia. Froude number scale model of an existing culvert was used. It was noticed that through rainfall event, the mobility of debris was impressed by stream shape (depth and width). The condition of the vegetation (size and quantities) through the catchment area was the main factor in debris transport. Rigby et al. [26] reported that steep slope was increasing the ability to mobilize debris that form field data of blocked culverts and bridges during a storm in Wollongong city.

Streftaris et al. [32] studied the probability of screen blockage by debris at trash screens through a numerical model to relate between the blockage probability and nature of the area around. Recently, many commercial computational fluid programs (CFD) such as SSIIM, Fluent, and FLOW 3D are used in the analysis of the scour process. Scour and sediment transport numerical model need to validate by using experimental data or field data [34][35][36][37][38]. Epely-Chauvin et al. [36] investigated numerically the effect of a series of parallel spur diked. The experimental data were compared by SSIIM and FLOW 3D program. It was found that the accuracy of calibrated FLOW 3D model was better than SSIIM model. Nielsen et al. [35] used the physical model and FLOW 3D model to analyze the scour process around the pile. The soil around the pile was uniform coarse stones in the physical models that were simulated by regular spheres, porous media, and a mixture of them. The calibrated porous media model can be used to determine the bed shear stress. In partially blocked culverts, there aren’t many studies that explain the blockage impact on scour dimensions. Sorourian et al. [14][15] studied the effect of inlet partial blockage on scour characteristics downstream box culvert. It resulted that the partial blockage at the culvert inlet could be the main factor in estimating the depth of scour. So, this study is aiming to investigate the effects of blockage through a box culvert on flow and scour characteristics by different blockage ratios and compares the results with a non-blocked case. Create a dimensionless equation relates the blockage ratio of the culvert with scour characteristics downstream culvert.

2. Experimental data

The experimental work of the study was conducted in the Hydraulics and Water Engineering Laboratory, Faculty of Engineering, Zagazig University, Egypt. The flume had a rectangular cross-section of 66 cm width, 65.5 cm depth, and 16.2 m long. A rectangular culvert was built with 0.2 m width, 0.2 m height and 3.00 m long with θ = 25° gradually outlet and 0.8 m fixed apron. The model was located on the mid-point of the channel. The sediment part was extended for a distance 2.20 m with 0.66 m width and 0.20 m depth of coarse sand with specific weight 1.60 kg/cm3, d50 = 2.75 mm and σ (d90/d50) = 1.50. The particle size distribution was as shown in Fig. 1. The experimental model was tested for different inlet flow (Q) of 25, 30, 34, 40 l/s for different submerged ratio (S) of 1.25, 1.50, 1.75.

3. Dimensional analysis

A dimensional analysis has been used to reduce the number of variables which affecting on the scour pattern downstream partial blocked culvert. The main factors affecting the maximum scour depth are:(2)ds=f(b.h.L.hb.lb.Q.ud.hu.hd.D50.ρ.ρs.g.ls.dd.ld)

Fig. 2 shows a definition sketch of the experimental model. The maximum scour depth can be written in a dimensionless form as:(3)dsh=f(B.Fd.S)where the ds/h is the relative maximum scour depth.

4. Numerical work

The FLOW 3D is (CFD) program used by many researchers and appeared high accuracy in solving hydrodynamic and sediment transport models in the three dimensions. Numerical simulation with FLOW 3D was performed to study the impacts of blockage ratio through box culvert on shear stress, velocity distribution and the sediment transport in terms of the hydrodynamic features (water surface, velocity and shear stress) and morphological parameters (scour depth and sizes) conditions in accurately and efficiently. The renormalization group (RNG) turbulence model was selected due to its high ability to predict the velocity profiles and turbulent kinetic energy for the flow through culvert [39]. The one-fluid incompressible mode was used to simulate the water surface. Volume of fluid (VOF) method was employed in FLOW 3D to tracks a liquid interface through arbitrary deformations and apply the correct boundary conditions at the interface [40].1.

Governing equations

Three-dimensional Reynolds-averaged Navier Stokes (RANS) equation was applied for incompressible viscous fluid motion. The continuity equation is as following:(4)VF∂ρ∂t+∂∂xρuAx+∂∂yρvAy+∂∂zρwAz=RDIF(5)∂u∂t+1VFuAx∂u∂x+vAy∂u∂y+ωAz∂u∂z=-1ρ∂P∂x+Gx+fx(6)∂v∂t+1VFuAx∂v∂x+vAy∂v∂y+ωAz∂v∂z=-1ρ∂P∂y+Gy+fy(7)∂ω∂t+1VFuAx∂ω∂x+vAy∂ω∂y+ωAz∂ω∂z=-1ρ∂P∂z+Gz+fz

ρ is the fluid density,

VF is the volume fraction,

(x,y,z) is the Cartesian coordinates,

(u,v,w) are the velocity components,

(Ax,Ay,Az) are the area fractions and

RDIF is the turbulent diffusion.

P is the average hydrodynamic pressure,

(Gx, Gy, Gz) are the body accelerations and

(fx, fy, fz) are the viscous accelerations.

The motion of sediment transport (suspended, settling, entrainment, bed load) is estimated by predicting the erosion, advection and deposition process as presented in [41].

The critical shields parameter is (θcr) is defined as the critical shear stress τcr at which sediments begin to move on a flat and horizontal bed [41]:(8)θcr=τcrgd50(ρs-ρ)

The Soulsby–Whitehouse [42] is used to predict the critical shields parameter as:(9)θcr=0.31+1.2d∗+0.0551-e(-0.02d∗)(10)d∗=d50g(Gs-1ν3where:

d* is the dimensionless grain size

Gs is specific weight (Gs = ρs/ρ)

The entrainment coefficient (0.005) was used to scale the scour rates and fit the experimental data. The settling velocity controls the Soulsby deposition equation. The volumetric sediment transport rate per width of the bed is calculated using Van Rijn [43].2.

Meshing and geometry of model

After many trials, it was found that the uniform cell size with 0.03 m cell size is the closest to the experimental results and takes less time. As shown in Fig. 3. In x-direction, the total model length in this direction is 700 cm with mesh planes at −100, 0, 300, 380 and 600 cm respectively from the origin point, in y-direction, the total model length in this direction is 66 cm at distances 0, 23, 43 and 66 cm respectively from the origin point. In z-direction, the total model length in this direction is 120 cm. with mesh planes at −20, 0, 20 and 100 cm respectively.3.

Boundary condition

As shown in Fig. 4, the boundary conditions of the model have been defined to simulate the experimental flow conditions accurately. The upstream boundary was defined as the volume flow rate with a different flow rate. The downstream boundary was defined as specific pressure with different fluid elevation. Both of the right side, the left side, and the bottom boundary were defined as a wall. The top boundary defined as specified pressure with pressure value equals zero.

5. Validation of experimental results and numerical results

The experimental results investigated the flow and scour characteristics downstream culvert due to different flow conditions. The measured value of maximum scour depth is compared with the simulated depth from FLOW 3D model as shown in Fig. 5. The scour results show that the simulated results from the numerical model is quite close to the experimental results with an average error of 3.6%. The water depths in numerical model results is so close to the experimental results as shown in Fig. 6 where the experiment and numerical results are compared at different submerged ratios and flow rates. The results appear maximum error percentage in water depths upstream and downstream the culvert is about 2.37%. This indicated that the FLOW 3D is efficient for the prediction of maximum scour depth and the flow depths downstream box culvert.

6. Computation time

The run time was chosen according to reaching to the stability limit. Hydraulic stability was achieved after 50 s, where the scour development may still go on. For run 1, the numerical simulation was run for 1000 s as shown in Fig. 7 where it mostly reached to scour stability at 800 s. The simulation time was taken 500 s at about 95% of scour stability.

7. Analysis and discussions

Fig. 8 shows the study sections where sec 1 represents to upstream section, sec2 represents to inside section and sec3 represents to downstream stream section. Table 1 indicates the scour hole dimensions at different blockage case. The symbol (B) represents to blockage and the number points to blockage ratio. B0 case signifies to the non-blocked case, B30 is that blockage height is 30% to the culvert height and so on.

Table 1. The scour results of different blockage ratio.

Casehb cmB = hb/hQ lit/sSFdd50 mmds/h measuredls/hdd/hld/hds/h estimated
B000351.261.692.50.581.500.275.000.46
B3060.30351.261.682.50.481.250.274.250.40
B50100.50351.221.742.50.451.100.244.000.37
B70140.70351.231.732.50.431.500.165.500.33

7.1. Scour hole geometry

The scour hole geometry mainly depends on the properties of soil of the bed downstream the fixed apron. From Table 1, the results show that the maximum scour depth in B0 case is about 0.58 of culvert height while the maximum deposition in B0 is 0.27 culvert height. There is a symmetric scour hole as shown in Fig. 9 in B0 case. An asymmetric scour hole is created in B50 and B70 due to turbulences that causes the deviation of the jet direction from the center of the flume where appear in Fig. 11 and Fig. 19.

7.2. Flow water surface

Fig. 10 presents the relative free surface water (hw/h) along the x-direction at center of the box culvert. From the mention Figure, it is easy to release the effect of different blockage ratios. The upstream water level rises by increasing the blockage ratio. Increasing upstream water level may cause flooding over the banks of the waterway. In the 70% blockage case, the upstream water level rises to 2.3 times of culvert height more than the non-blocked case at the same discharge and submerged ratio. The water surface profile shows an increase in water level upstream the culvert due to a decrease in transverse velocity. Because of decreasing velocity downstream culvert, there is an increase in water level before it reaches its uniform depth.

7.3. Velocity vectors

Scour downstream hydraulic structures mainly affects by velocities distribution and bed shear stress. Fig. 11 shows the velocity vectors and their magnitude in xz plane at the same flow conditions. The difference in the upstream water level due to the different blockage ratios is so clear. The maximum water level is in B70 and the minimum level is in B0. The inlet mean velocity value is about 0.88 m/s in B0 increases to 2.86 m/s in B70. As the blockage ratio increases, the inlet velocity increases. The outlet velocity in B0 case makes downward jet causes scour hole just after the fixed apron in the middle of the bed while the blockage causes upward water flow that appears clearly in B70. The upward jet decreases the scour depth to 0.13 culvert height less than B0 case. After the scour hole, the velocity decreases and the flow becomes uniform.

7.4. Velocity distribution

Fig. 12 represents flow velocity (Vx) distribution along the vertical depth (z/hu) upstream the inlet for the different blockage ratios at the same flow conditions. From the Figure, the maximum velocity creates closed to bed in B0 while in blocked case, the maximum horizontal velocity creates at 0.30 of relative vertical depth (z/hu). Fig. 13 shows the (Vz) distribution along the vertical depth (z/hu) upstream culvert at sec 1. From the mentioned Figure, it is easy to note that the maximum vertical is in B70 which appears that as the blockage ratio increases the vertical ratio also increases. In the non-blocked case. The vertical velocity (Vz) is maximum at (z/hu) equals 0.64. At the end of the fixed apron (sec 3), the horizontal velocity (Vx) is slowly increasing to reach the maximum value closed to bed in B0 and B30 while the maximum horizontal velocity occurs near to the top surface in B50 and B70 as shown in Fig. 14. The vertical velocity component along the vertical depth (z/hd) is presented in Fig. 15. The vertical velocity (Vz) is maximum in B0 at vertical depth (z/hd) 0.3 with value 0.45 m/s downward. Figs. 16 and 17 observe velocity components (Vx, Vz) along the vertical depth just after the end of blockage length at the centerline of the culvert barrel. It could be noticed the uniform velocity distribution in B0 case with horizontal velocity (Vx) closed to 1.0 m/s and vertical velocity closed to zero. In the blocked case, the maximum horizontal velocity occurs in depth more than the blockage height.

7.5. Bed velocity distribution

Fig. 18 presents the x-velocity vectors at 1.5 cm above the bed for different blockage ratios from the velocity vectors distribution and magnitude, it is easy to realize the position of the scour hole and deposition region. In B0 and B30, the flow is symmetric so that the scour hole is created around the centerline of flow while in B50 and B70 cases, the flow is asymmetric and the scour hole creates in the right of flow direction in B50. The maximum scour depth is found in the left of flow direction in B70 case where the high velocity region is found.

8. Maximum scour depth prediction

Regression analysis is used to estimate maximum scour depth downstream box culvert for different ratios of blockage by correlating the maximum relative scour by other variables that affect on it in one formula. An equation is developed to predict maximum scour depth for blocked and non-blocked. As shown in the equation below, the relative maximum scour depth(ds/hd) is a function of densimetric Froude number (Fd), blockage ratio (B) and submerged ratio (S)(11)dsh=0.56Fd-0.20B+0.45S-1.05

In this equation the coefficient of correlation (R2) is 0.82 with standard error equals 0·08. The developed equation is valid for Fd = [0.9 to 2.10] and submerged ratio (S) ≥ 1.00. Fig. 19 shows the comparison between relative maximum scour depths (ds/h) measured and estimated for different blockage ratios. Fig. 20 clears the comparison between residuals and ds/h estimated for the present study. From these figures, it could be noticed that there is a good agreement between the measured and estimated relative scour depth.

9. Comparison with previous scour equations

Many previous scour formulae have been produced for calculation the maximum scour depth downstream non-blockage culvert. These equations have been included the effect of flow regime, culvert shape, soil properties and the flow rate on maximum scour depth. Two of previous experimental studies data have been chosen to be compared with the present study results in non-blocked study data. Table 2 shows comparison of culvert shape, densmetric Froude number, median particle size and scour equations for these previous studies. By applying the present study data in these studies scour formula as shown in Fig. 21, it could be noticed that there are a good agreement between present formula results and others empirical equations results. Where that Lim [44] and Abt [4] are so closed to the present study data.

Table 2. Comparison of some previous scour formula.

ResearchersFdCulvert shaped50(mm)Proposed equationSubmerged ratio
Present study0.9–2.11square2.75dsh=0.56Fd-0.20B+0.45S-1.051.25–1.75
Lim [44]1–10Circular1.65dsh=0.45Fd0.47
Abt [4]Fd ≥ 1Circular0.22–7.34-dsh=3.67Fd0.57∗D500.4∗σ-0.4

10. Conclusions

The present study has shown that the FLOW 3D model can accurately simulate water surface and the scour hole characteristics downstream the box culvert with error percentage in water depths does not exceed 2.37%. Velocities distribution through and outlets culvert barrel helped on understanding the scour hole shape.

The blockage through culvert had caused of increasing of water surface upstream structure where the upstream water level in B70 was 2.3 of culvert height more than non-blocked case at the same discharge that could be dangerous on the stability of roads above. The depth averaged velocity through culvert barrel increased by 3 times its value in non-blocked case.

On the other hand, blockage through culvert had a limited effect on the maximum scour depth. The little effect of blockage on maximum scour depth could be noticed in Fig. 11. From this Figure, it could be noted that the residual part of culvert barrel after the blockage part had made turbulences. These turbulences caused the deviation of the flow resulting in the formation of asymmetric scour hole on the side of channel. This not only but in B70 the blockage height caused upward jet which made a wide far scour hole as cleared from the results in Table 1.

An empirical equation was developed from the results to estimate the maximum scour depth relative to culvert height function of blockage ratio (B), submerged ratio (S), and densimetric Froude number (Fd). The equation results was compared with some scour formulas at the same densimetric Froude number rang where the present study results was in between the other equations results as shown in Fig. 21.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

References

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Peer review under responsibility of Faculty of Engineering, Alexandria University.

Figure 1- Schematic diagram of pooled stepped spillway conducted by Felder et al. (2012A): Notes: h step height (10 cm): w pool height (3.1 cm): l horizontal step length (20 cm): lw pool weir length (1.5 cm): d' is the water depth above the crest; y' is the distance normal to the crest invert

Study of inception point, void fraction and pressure over pooled stepped spillways using Flow-3D

Khosro Morovati , Afshin Eghbalzadeh 
International Journal of Numerical Methods for Heat & Fluid Flow

ISSN: 0961-5539

Article publication date: 3 April 2018

Abstract

많은 계단식 배수로 지오메트리 설계 지침이 평평한 단계를 위해 개발되었지만 통합 단계를 설계하는 것이 더 효율적으로 작동하는 배수로에 대한 적절한 대안이 될 수 있습니다.

이 논문은 POOL의 다른 높이에서 공기 연행과 보이드 비율의 시작점을 다루는 것을 목표로 합니다. 그 후, FLOW-3D 소프트웨어를 사용하여 POOL과 경사면의 높이를 다르게 하여 폭기된 지역과 폭기되지 않은 지역에서 압력 분포를 평가했습니다.

얻어진 수치 결과와 실험 결과의 비교는 본 연구에 사용된 모든 방류에 대해 잘 일치했습니다. POOL 높이는 시작 지점 위치에 미미한 영향을 미쳤습니다. 공극률의 값은 높은 방류에 비해 낮은 방전에서 더 많은 영향을 받았습니다.

여수로의 마루(통기되지 않은 지역)에서는 음압이 나타나지 않았으며 각 방류에서 마루를 따라 높이가 15cm인 수영장에서 최대 압력 값이 얻어졌습니다.

모든 사면에서 웅덩이 및 평평한 계단형 여수로의 계단층 부근에서는 음압이 형성되지 않았습니다. 그러나 평단식 여수로에 비해 평단식 여수로의 수직면 부근에서 음압이 더 많이 형성되어 평단식 슈트에서 캐비테이션 현상이 발생할 확률이 증가하였습니다.

Study of inception point, void fraction and pressure over pooled
stWhile many stepped spillways geometry design guidelines were developed for flat steps, designing pooled steps might be an appropriate alternative to spillways working more efficiency. This paper aims to deal with the inception point of air-entrainment and void fraction in the different height of the pools. Following that, pressure distribution was evaluated in aerated and non-aerated regions under the effect of different heights of the pools and slopes through the use of the FLOW-3D software. Comparison of obtained numerical results with experimental ones was in good agreement for all discharges used in this study. Pools height had the insignificant effect on the inception point location. The value of void fraction was more affected in lower discharges in comparison with higher ones. Negative pressure was not seen over the crest of spillway (non-aerated region), and the maximum pressure values were obtained for pools with 15 cm height along the crest in each discharge. In all slopes, negative pressure was not formed near the step bed in the pooled and flat stepped spillways. However, negative pressure was formed in more area near the vertical face in the flat stepped spillway compared with the pooled stepped spillway which increases the probability of cavitation phenomenon in the flat stepped chute.

Design/methodology/approach

압력, 공극률 및 시작점을 평가하기 위해 POOL된 계단식 여수로가 사용되었습니다. 또한 POOL의 다른 높이가 사용되었습니다. 이 연구의 수치 시뮬레이션은 Flow-3D 소프트웨어를 통해 수행되었습니다. 얻어진 결과는 풀이 압력, 공극률 및 시작점을 포함한 2상 유동 특성에 영향을 미칠 수 있음을 나타냅니다.

Findings

마루 위에는 음압이 보이지 않았습니다. 압력 값은 사용된 모든 높이와 15cm 높이에서 얻은 최대 값에 대해 다릅니다. 또한, 풀링 스텝은 플랫 케이스에 비해 음압점 감소에 더 효과적인 역할을 하였습니다. 시작 지점 위치는 특히 9 및 15cm 높이에 대해 스키밍 흐름 영역과 비교하여 낮잠 및 전환 흐름 영역에서 더 많은 영향을 받았습니다.

Keywords

Citation

Morovati, K. and Eghbalzadeh, A. (2018), “Study of inception point, void fraction and pressure over pooled stepped spillways using Flow-3D”, International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 28 No. 4, pp. 982-998. https://doi.org/10.1108/HFF-03-2017-0112

Figure 1- Schematic diagram of pooled stepped spillway conducted by Felder et al. (2012A): Notes: h  step height (10 cm): w pool height (3.1 cm): l horizontal step length (20 cm): lw pool weir length (1.5 cm):  d' is the water depth above the crest; y' is the distance normal to the crest invert
Figure 1- Schematic diagram of pooled stepped spillway conducted by Felder et al. (2012A): Notes: h step height (10 cm): w pool height (3.1 cm): l horizontal step length (20 cm): lw pool weir length (1.5 cm): d’ is the water depth above the crest; y’ is the distance normal to the crest invert
Figure 2- meshing domain and distribution of blocks
Figure 2- meshing domain and distribution of blocks
Figure 3- Comparison of numerical simulation with experimental data by Felder et al. (2012A);  mesh convergence analysis; pooled stepped spillway (slope: 26.6 0 )
Figure 3- Comparison of numerical simulation with experimental data by Felder et al. (2012A); mesh convergence analysis; pooled stepped spillway (slope: 26.6 0 )
Figure 4- Comparison of numerical simulation with experimental data by Felder et al. (2012A);  Flat stepped spillway (slope: 0 26 6. )
Figure 4- Comparison of numerical simulation with experimental data by Felder et al. (2012A); Flat stepped spillway (slope: 0 26 6. )
Figure 5-Comparison of numerical simulation with experimental data by Felder et al. (2012B); pooled  and flat stepped spillways (slope: 0 9.8 )
Figure 5-Comparison of numerical simulation with experimental data by Felder et al. (2012B); pooled and flat stepped spillways (slope: 0 9.8 )
Figure 6- TKE distribution on steps 8, 9 and 10 for four different mesh numbers: 261252 (model 1),  288941 (model 2), 323578 (model 3) and 343154 (model 4)
Figure 6- TKE distribution on steps 8, 9 and 10 for four different mesh numbers: 261252 (model 1), 288941 (model 2), 323578 (model 3) and 343154 (model 4)
Figure 7- Comparison of obtained Void fraction distribution on step 10 in numerical simulation with  experimental work conducted by Felder et al. (2012A); (slope 26.60 )
Figure 7- Comparison of obtained Void fraction distribution on step 10 in numerical simulation with experimental work conducted by Felder et al. (2012A); (slope 26.60 )
Figure 8- Results of inception point of air entrainment in different height of the pools: comparison with  empirical correlations (Eqs 8-9), experimental (Felder et al. (2012A)) and numerical data
Figure 8- Results of inception point of air entrainment in different height of the pools: comparison with empirical correlations (Eqs 8-9), experimental (Felder et al. (2012A)) and numerical data
Figure 9- Void fraction distribution for different pool heights on steps 10; slope 26.6 0
Figure 9- Void fraction distribution for different pool heights on steps 10; slope 26.6 0
Figure 10- Comparison of pressure distribution between numerical simulation and experimental work  conducted by Zhang and Chanson (2016); flat stepped spillway (slope: 0 45 )
Figure 10- Comparison of pressure distribution between numerical simulation and experimental work conducted by Zhang and Chanson (2016); flat stepped spillway (slope: 0 45 )
Figure 11- A comparison of the pressure distribution above the crest of the spillway; B comparison of the  free surface profile along the crest of the spillway.  Note: x' indicates the longitudinal distance from the starting point of the crest.
Figure 11- A comparison of the pressure distribution above the crest of the spillway; B comparison of the free surface profile along the crest of the spillway. Note: x’ indicates the longitudinal distance from the starting point of the crest.
Figure 12- pressure distribution along crest of spillway in different discharges; slope 26.6
Figure 12- pressure distribution along crest of spillway in different discharges; slope 26.6
Figure 13- Pressure distribution near the last step bed for different slopes and discharges: x'' indicatesthe  longitudinal distance from the intersection of the horizontal and vertical faces of step 10; y" is the distance from the intersection of the horizontal and vertical faces in the vertical direction
Figure 13- Pressure distribution near the last step bed for different slopes and discharges: x” indicatesthe longitudinal distance from the intersection of the horizontal and vertical faces of step 10; y” is the distance from the intersection of the horizontal and vertical faces in the vertical direction
Figure 14- Pressure distribution adjacent the vertical face of step 9 for different discharges and slopes
Figure 14- Pressure distribution adjacent the vertical face of step 9 for different discharges and slopes
Table1- Used discharges for assessments of mesh convergence analysis and hydraulic  characteristics
Table1- Used discharges for assessments of mesh convergence analysis and hydraulic characteristics

Conclusion

본 연구에서는 자유표면을 모사하기 위해 VOF 방법과 k -ε (RNG) 난류 모델을 활용하여 FLOW-3D 소프트웨어를 사용하였고, 계단식 배수로의 유동을 모사하기 위한 목적으로 난류 특성을 모사하였다. 얻은 결과는 수치 모델이 시작점 위치, 보이드 비율 및 압력을 적절하게 시뮬레이션했음을 나타냅니다. 풀의 높이는 공기 유입 위치에 미미한 영향을 미치므로 얻은 결과는 이 문서에서 제시된 상관 관계와 잘 일치했습니다. 즉, 사용 가능한 상관 관계를 서로 다른 풀 높이에 사용할 수 있습니다. 공극률의 결과는 스텝 풀 근처의 나프 유동 영역에서 공극율 값이 다른 배출보다 더 큰 것으로 나타났다. 더욱이 고방출량 .0 113m3/s에서 수영장 높이를 변경해도 수영장 표면 근처의 공극률 값에는 영향을 미치지 않았습니다.

낮잠 및 전환 체제의 압력 분포에 대한 0 및 3cm 높이의 수영장 효과는 많은 지점에서 대부분 유사했습니다. 더욱이 조사된 모든 높이에서 여수로의 마루를 따라 부압이 없었습니다. 여수로 끝단의 바닥 부근의 압력 결과는 평평하고 고인 경우 부압이 발생하지 않았음을 나타냅니다. 수직면 부근의 음압은 웅덩이에 비해 평평한 계단형 여수로의 깊이(w=0 cm)의 대부분에서 발생하였다. 또한 더 큰 사면에 대한 풀링 케이스에서 음압이 제거되었습니다. 평단식 여수로에서는 계단의 수직면에 인접한 더 넓은 지역에서 음압이 발생하였기 때문에 이 여수로에서는 고형단식여수로보다 캐비테이션 현상이 발생할 가능성이 더 큽니다.

In this study, the FLOW-3D software was used through utilizing the VOF method and k −ε (RNG) turbulence model in order to simulate free surface, and turbulence characteristics for the purpose of simulating flow over pooled stepped spillway. The results obtained indicated that the numerical model properly simulated the inception point location, void fraction, and pressure. The height of the pools has the insignificant effect on the location of air entrainment, so that obtained results were in good agreement with the correlations presented in this paper. In other words, available correlations can be used for different pool heights. The results of void fraction showed that the void fraction values in nappe flow regime near the step pool were more than the other discharges. Furthermore in high discharge, 0.113m3/s, altering pool height had no effect on the value of void fraction near the pool surface.

The effect of the pools with 0 and 3 cm heights over the pressure distribution in nappe and transition regimes was mostly similar in many points. Furthermore, in all examined heights there was no negative pressure along the crest of the spillway. The pressure results near the bed of the step at the end of the spillway indicated that negative pressure did not occur in the flat and pooled cases. Negative pressure near the vertical face occurred in the most part of the depth in the flat stepped spillway (w=0 cm) in comparison with the pooled case. Also, the negative pressure was eliminated in the pooled case for the larger slopes. Since negative pressure occurred in a larger area adjacent the vertical face of the steps in the flat stepped spillways, it is more likely that cavitation phenomenon occurs in this spillway rather than the pooled stepped spillways.

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Fig. 5 Comparison of experimental SEM image and CtFD simulated melt pool with beam diameters of(a)700 μm,(b)1000 μm, and(c)1300 μm and an absorption rate of 0.3. Electron beam power and scan speed are 900 W and 100 mm s-1, respectively

추가 생산용 전자빔 조사에 의한 316L 스테인리스 용융 · 응고 거동

Melting and Solidification Behavior of 316L Steel Induced by Electron-Beam Irradiation for Additive Manufacturing

付加製造用電子ビーム照射による 316L ステンレス鋼の溶融・凝固挙動

奥 川 将 行*・宮 田 雄一朗*・王     雷*・能 勢 和 史*
小 泉 雄一郎*・中 野 貴 由*
Masayuki OKUGAWA, Yuichiro MIYATA, Lei WANG, Kazufumi NOSE,
Yuichiro KOIZUMI and Takayoshi NAKANO

Abstract

적층 제조(AM) 기술은 복잡한 형상의 3D 부품을 쉽게 만들고 미세 구조 제어를 통해 재료 특성을 크게 제어할 수 있기 때문에 많은 관심을 받았습니다. PBF(Powderbed fusion) 방식의 AM 공정에서는 금속 분말을 레이저나 전자빔으로 녹이고 응고시키는 과정을 반복하여 3D 부품을 제작합니다.

일반적으로 응고 미세구조는 Hunt[Mater. 과학. 영어 65, 75(1984)]. 그러나 CET 이론이 일반 316L 스테인리스강에서도 높은 G와 R로 인해 PBF형 AM 공정에 적용될 수 있을지는 불확실하다.

본 연구에서는 미세구조와 응고 조건 간의 관계를 밝히기 위해 전자빔 조사에 의해 유도된 316L 강의 응고 미세구조를 분석하고 CtFD(Computational Thermal-Fluid Dynamics) 방법을 사용하여 고체/액체 계면에서의 응고 조건을 평가했습니다.

CET 이론과 반대로 높은 G 조건에서 등축 결정립이 종종 형성되는 것으로 밝혀졌다. CtFD 시뮬레이션은 약 400 mm s-1의 속도까지 유체 흐름이 있음을 보여 주며 수상 돌기의 파편 및 이동의 영향으로 등축 결정립이 형성됨을 시사했습니다.

Additive manufacturing(AM)technologies have attracted much attention because it enables us to build 3D parts with complicated geometry easily and control material properties significantly via the control of microstructures. In the powderbed fusion(PBF)type AM process, 3D parts are fabricated by repeating a process of melting and solidifying metal powders by laser or electron beams. In general, the solidification microstructures can be predicted from solidification conditions defined by the combination of temperature gradient G and solidification rate R on the basis of columnar-equiaxed transition(CET)theory proposed by Hunt [Mater. Sci. Eng. 65, 75(1984)]. However, it is unclear whether the CET theory can be applied to the PBF type AM process because of the high G and R, even for general 316L stainless steel. In this study, to reveal relationships between microstructures and solidification conditions, we have analyzed solidification microstructures of 316L steel induced by electronbeam irradiation and evaluated solidification conditions at the solid/liquid interface using a computational thermal-fluid dynamics (CtFD)method. It was found that equiaxed grains were often formed under high G conditions contrary to the CET theory. CtFD simulation revealed that there is a fluid flow up to a velocity of about 400 mm s-1, and suggested that equiaxed grains are formed owing to the effect of fragmentations and migrations of dendrites.

Keywords

Additive Manufacturing, 316L Stainless Steel, Powder Bed Fusion, Electron Beam Melting, Computational Thermal
Fluid Dynamics Simulation

Fig. 1 Width, height, and height differences calculated from laser microscope analysis of melt tracks formed by scanning electron beam. Fig. 2(a)Scanning electron microscope(SEM)image and(b) corresponding electron back-scattering diffraction(EBSD) IPF-map taken from the electron-beam irradiated region in P900-V100 sample. Fig. 3 Average grain size and their aspect ratio calculated from EBSD IPF-map taken from the electron-beam irradiated region.
Fig. 1 Width, height, and height differences calculated from laser microscope analysis of melt tracks formed by scanning electron beam. Fig. 2(a)Scanning electron microscope(SEM)image and(b) corresponding electron back-scattering diffraction(EBSD) IPF-map taken from the electron-beam irradiated region in P900-V100 sample. Fig. 3 Average grain size and their aspect ratio calculated from EBSD IPF-map taken from the electron-beam irradiated region.
Fig. 4 Comparison of experimental SEM image and computational thermal fluid dynamics(CtFD)simulated melt pool with a beam diameter of 700 μm and absorption rates of(a)0.3,(b)0.5, and (c)0.7. Electron beam power and scan speed are 900 W and 100 mm s-1, respectively.
Fig. 4 Comparison of experimental SEM image and computational thermal fluid dynamics(CtFD)simulated melt pool with a beam diameter of 700 μm and absorption rates of(a)0.3,(b)0.5, and (c)0.7. Electron beam power and scan speed are 900 W and 100 mm s-1, respectively.
Fig. 5 Comparison of experimental SEM image and CtFD simulated melt pool with beam diameters of(a)700 μm,(b)1000 μm, and(c)1300 μm and an absorption rate of 0.3. Electron beam power and scan speed are 900 W and 100 mm s-1, respectively
Fig. 5 Comparison of experimental SEM image and CtFD simulated melt pool with beam diameters of(a)700 μm,(b)1000 μm, and(c)1300 μm and an absorption rate of 0.3. Electron beam power and scan speed are 900 W and 100 mm s-1, respectively
Fig. 6 Depth of melt tracks calculated from experimental SEM image and CtFD simulation results.
Fig. 6 Depth of melt tracks calculated from experimental SEM image and CtFD simulation results.
Fig. 7 G-R plots of 316L steel colored by(a)aspect ratio of crystalline grains and(b)fluid velocity.
Fig. 7 G-R plots of 316L steel colored by(a)aspect ratio of crystalline grains and(b)fluid velocity.
Fig. 8 Comparison of solidification microstructure(EBSD IPF-map)of melt region formed by scanning electron beam and corresponding snap shot of CtFD simulation colored by fluid velocity
Fig. 8 Comparison of solidification microstructure(EBSD IPF-map)of melt region formed by scanning electron beam and corresponding snap shot of CtFD simulation colored by fluid velocity

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Figure 17. Longitudinal turbulent kinetic energy distribution on the smooth and triangular macroroughnesses: (A) Y/2; (B) Y/6.

Numerical Simulations of the Flow Field of a Submerged Hydraulic Jump over Triangular Macroroughnesses

Triangular Macroroughnesses 대한 잠긴 수압 점프의 유동장 수치 시뮬레이션

by Amir Ghaderi 1,2,Mehdi Dasineh 3,Francesco Aristodemo 2 andCostanza Aricò 4,*1Department of Civil Engineering, Faculty of Engineering, University of Zanjan, Zanjan 537138791, Iran2Department of Civil Engineering, University of Calabria, Arcavacata, 87036 Rende, Italy3Department of Civil Engineering, Faculty of Engineering, University of Maragheh, Maragheh 8311155181, Iran4Department of Engineering, University of Palermo, Viale delle Scienze, 90128 Palermo, Italy*Author to whom correspondence should be addressed.Academic Editor: Anis YounesWater202113(5), 674; https://doi.org/10.3390/w13050674

Abstract

The submerged hydraulic jump is a sudden change from the supercritical to subcritical flow, specified by strong turbulence, air entrainment and energy loss. Despite recent studies, hydraulic jump characteristics in smooth and rough beds, the turbulence, the mean velocity and the flow patterns in the cavity region of a submerged hydraulic jump in the rough beds, especially in the case of triangular macroroughnesses, are not completely understood. The objective of this paper was to numerically investigate via the FLOW-3D model the effects of triangular macroroughnesses on the characteristics of submerged jump, including the longitudinal profile of streamlines, flow patterns in the cavity region, horizontal velocity profiles, streamwise velocity distribution, thickness of the inner layer, bed shear stress coefficient, Turbulent Kinetic Energy (TKE) and energy loss, in different macroroughness arrangements and various inlet Froude numbers (1.7 < Fr1 < 9.3). To verify the accuracy and reliability of the present numerical simulations, literature experimental data were considered.

Keywords: submerged hydraulic jumptriangular macroroughnessesTKEbed shear stress coefficientvelocityFLOW-3D model

수중 유압 점프는 강한 난류, 공기 동반 및 에너지 손실로 지정된 초임계에서 아임계 흐름으로의 급격한 변화입니다. 최근 연구에도 불구하고, 특히 삼각형 거시적 거칠기의 경우, 평활 및 거친 베드에서의 수압 점프 특성, 거친 베드에서 잠긴 수압 점프의 공동 영역에서 난류, 평균 속도 및 유동 패턴이 완전히 이해되지 않았습니다.

이 논문의 목적은 유선의 종방향 프로파일, 캐비티 영역의 유동 패턴, 수평 속도 프로파일, 스트림 방향 속도 분포, 두께를 포함하여 서브머지드 점프의 특성에 대한 삼각형 거시 거칠기의 영향을 FLOW-3D 모델을 통해 수치적으로 조사하는 것이었습니다.

내부 층의 층 전단 응력 계수, 난류 운동 에너지(TKE) 및 에너지 손실, 다양한 거시 거칠기 배열 및 다양한 입구 Froude 수(1.7 < Fr1 < 9.3). 현재 수치 시뮬레이션의 정확성과 신뢰성을 검증하기 위해 문헌 실험 데이터를 고려했습니다.

 Introduction

격렬한 난류 혼합과 기포 동반이 있는 수압 점프는 초임계에서 아임계 흐름으로의 변화 과정으로 간주됩니다[1]. 자유 및 수중 유압 점프는 일반적으로 게이트, 배수로 및 둑과 같은 수력 구조 아래의 에너지 손실에 적합합니다. 매끄러운 베드에서 유압 점프의 특성은 널리 연구되었습니다[2,3,4,5,6,7,8,9].

베드의 거칠기 요소가 매끄러운 베드와 비교하여 수압 점프의 특성에 어떻게 영향을 미치는지 예측하기 위해 거시적 거칠기에 대한 자유 및 수중 수력 점프에 대해 여러 실험 및 수치 연구가 수행되었습니다. Ead와 Rajaratnam[10]은 사인파 거대 거칠기에 대한 수리학적 점프의 특성을 조사하고 무차원 분석을 통해 수면 프로파일과 배출을 정규화했습니다.

Tokyayet al. [11]은 두 사인 곡선 거대 거칠기에 대한 점프 길이 비율과 에너지 손실이 매끄러운 베드보다 각각 35% 더 작고 6% 더 높다는 것을 관찰했습니다. Abbaspur et al. [12]는 6개의 사인파형 거대 거칠기에 대한 수력학적 점프의 특성을 연구했습니다. 그 결과, 꼬리수심과 점프길이는 평상보다 낮았고 Froude 수는 점프길이에 큰 영향을 미쳤습니다.

Shafai-Bejestan과 Neisi[13]는 수압 점프에 대한 마름모꼴 거대 거칠기의 영향을 조사했습니다. 결과는 마름모꼴 거시 거칠기를 사용하면 매끄러운 침대와 비교하여 꼬리 수심과 점프 길이를 감소시키는 것으로 나타났습니다. Izadjoo와 Shafai-Bejestan[14]은 다양한 사다리꼴 거시 거칠기에 대한 수압 점프를 연구했습니다.

그들은 전단응력계수가 평활층보다 10배 이상 크고 점프길이가 50% 감소하는 것을 관찰하였습니다. Nikmehr과 Aminpour[15]는 Flow-3D 모델 버전 11.2[16]를 사용하여 사다리꼴 블록이 있는 거시적 거칠기에 대한 수력학적 점프의 특성을 조사했습니다. 결과는 거시 거칠기의 높이와 거리가 증가할수록 전단 응력 계수뿐만 아니라 베드 근처에서 속도가 감소하는 것으로 나타났습니다.

Ghaderi et al. [17]은 다양한 형태의 거시 거칠기(삼각형, 정사각형 및 반 타원형)에 대한 자유 및 수중 수력 점프 특성을 연구했습니다. 결과는 Froude 수의 증가에 따라 자유 및 수중 점프에서 전단 응력 계수, 에너지 손실, 수중 깊이, 미수 깊이 및 상대 점프 길이가 증가함을 나타냅니다.

자유 및 수중 점프에서 가장 높은 전단 응력과 에너지 손실은 삼각형의 거시 거칠기가 존재할 때 발생했습니다. Elsebaie와 Shabayek[18]은 5가지 형태의 거시적 거칠기(삼각형, 사다리꼴, 2개의 측면 경사 및 직사각형이 있는 정현파)에 대한 수력학적 점프의 특성을 연구했습니다. 결과는 모든 거시적 거칠기에 대한 에너지 손실이 매끄러운 베드에서보다 15배 이상이라는 것을 보여주었습니다.

Samadi-Boroujeni et al. [19]는 다양한 각도의 6개의 삼각형 거시 거칠기에 대한 수력 점프를 조사한 결과 삼각형 거시 거칠기가 평활 베드에 비해 점프 길이를 줄이고 에너지 손실과 베드 전단 응력 계수를 증가시키는 것으로 나타났습니다.

Ahmed et al. [20]은 매끄러운 베드와 삼각형 거시 거칠기에서 수중 수력 점프 특성을 조사했습니다. 결과는 부드러운 침대와 비교할 때 잠긴 깊이와 점프 길이가 감소했다고 밝혔습니다. 표 1은 다른 연구자들이 제시한 과거의 유압 점프에 대한 실험 및 수치 연구의 세부 사항을 나열합니다.

Table 1. Main characteristics of some past experimental and numerical studies on hydraulic jumps.

ReferenceShape Bed-Channel Type-
Jump Type
Channel Dimension (m)Roughness (mm)Fr1Investigated Flow
Properties
Ead and Rajaratnam [10]-Smooth and rough beds-Rectangular channel-Free jumpCL1 = 7.60
CW2 = 0.44
CH3 = 0.60
-Corrugated sheets (RH4 = 13 and 22)4–10-Upstream and tailwater depths-Jump length-Roller length-Velocity-Water surface profile
Tokyay et al. [11]-Smooth and rough beds-Rectangular channel-Free jumpCL = 10.50
CW = 0.253
CH = 0.432
-Two sinusoidal corrugated (RH = 10 and 13)5–12-Depth ratio-Jump length-Energy loss
Izadjoo and Shafai-Bejestan [14]-Smooth and rough beds-Two rectangular-channel-Free jumpCL = 1.2, 9
CW = 0.25, 0.50
CH = 0.40
Baffle with trapezoidal cross section
(RH: 13 and 26)
6–12-Upstream and tailwater depths-Jump length-Velocity-Bed shear stress coefficient
Abbaspour et al. [12]-Horizontal bed with slope 0.002-Rectangular channel—smooth and rough beds-Free jumpCL = 10
CW = 0.25
CH = 0.50
-Sinusoidal bed (RH = 15,20, 25 and 35)3.80–8.60-Water surface profile-Depth ratio-Jump length-Energy loss-Velocity profiles-Bed shear stress coefficient
Shafai-Bejestan and Neisi [13]-Smooth and rough beds-Rectangular channel-Free jumpCL = 7.50
CW = 0.35
CH = 0.50
Lozenge bed4.50–12-Sequent depth-Jump length
Elsebaie and Shabayek [18]-Smooth and rough beds-Rectangular channel-With side slopes of 45 degrees for two trapezoidal and triangular macroroughnesses and of 60 degrees for other trapezoidal macroroughnesses-Free jumpCL = 9
CW = 0.295
CH = 0.32
-Sinusoidal-Triangular-Trapezoidal with two side-Rectangular-(RH = 18 and corrugation wavelength = 65)50-Water surface profile-Sequent depth-Jump length-Bed shear stress coefficient
Samadi-Boroujeni et al. [19]-Rectangular channel-Smooth and rough beds-Free jumpCL = 12
CW = 0.40
CH = 0.40
-Six triangular corrugated (RH = 2.5)6.10–13.10-Water surface profile-Sequent depth-Jump length-Energy loss-Velocity profiles-Bed shear stress coefficient
Ahmed et al. [20]-Smooth and rough beds-Rectangular channel-Submerged jumpCL = 24.50
CW = 0.75
CH = 0.70
-Triangular corrugated sheet (RH = 40)1.68–9.29-Conjugated and tailwater depths-Submerged ratio-Deficit depth-Relative jump length-Jump length-Relative roller jump length-Jump efficiency-Bed shear stress coefficient
Nikmehr and Aminpour [15]-Horizontal bed with slope 0.002-Rectangular channel-Rough bed-Free jumpCL = 12
CW = 0.25
CH = 0.50
-Trapezoidal blocks (RH = 2, 3 and 4)5.01–13.70-Water surface profile-Sequent depth-Jump length-Roller length-Velocity
Ghaderi et al. [17]-Smooth and rough beds-Rectangular channel-Free and submerged jumpCL = 4.50
CW = 0.75
CH = 0.70
-Triangular, square and semi-oval macroroughnesses (RH = 40 and distance of roughness of I = 40, 80, 120, 160 and 200)1.70–9.30-Horizontal velocity distributions-Bed shear stress coefficient-Sequent depth ratio and submerged depth ratio-Jump length-Energy loss
Present studyRectangular channel
Smooth and rough beds
Submerged jump
CL = 4.50
CW = 0.75
CH = 0.70
-Triangular macroroughnesses (RH = 40 and distance of roughness of I = 40, 80, 120, 160 and 200)1.70–9.30-Longitudinal profile of streamlines-Flow patterns in the cavity region-Horizontal velocity profiles-Streamwise velocity distribution-Bed shear stress coefficient-TKE-Thickness of the inner layer-Energy loss

CL1: channel length, CW2: channel width, CH3: channel height, RH4: roughness height.

이전에 논의된 조사의 주요 부분은 실험실 접근 방식을 기반으로 하며 사인파, 마름모꼴, 사다리꼴, 정사각형, 직사각형 및 삼각형 매크로 거칠기가 공액 깊이, 잠긴 깊이, 점프 길이, 에너지 손실과 같은 일부 자유 및 수중 유압 점프 특성에 어떻게 영향을 미치는지 조사합니다.

베드 및 전단 응력 계수. 더욱이, 저자[17]에 의해 다양한 형태의 거시적 거칠기에 대한 수력학적 점프에 대한 이전 발표된 논문을 참조하면, 삼각형의 거대조도는 가장 높은 층 전단 응력 계수 및 에너지 손실을 가지며 또한 가장 낮은 잠긴 깊이, tailwater를 갖는 것으로 관찰되었습니다.

다른 거친 모양, 즉 정사각형 및 반 타원형과 부드러운 침대에 비해 깊이와 점프 길이. 따라서 본 논문에서는 삼각형 매크로 거칠기를 사용하여(일정한 거칠기 높이가 T = 4cm이고 삼각형 거칠기의 거리가 I = 4, 8, 12, 16 및 20cm인 다른 T/I 비율에 대해), 특정 캐비티 영역의 유동 패턴, 난류 운동 에너지(TKE) 및 흐름 방향 속도 분포와 같은 연구가 필요합니다.

CFD(Computational Fluid Dynamics) 방법은 자유 및 수중 유압 점프[21]와 같은 복잡한 흐름의 모델링 프로세스를 수행하는 중요한 도구로 등장하며 수중 유압 점프의 특성은 CFD 시뮬레이션을 사용하여 정확하게 예측할 수 있습니다 [22,23 ].

본 논문은 초기에 수중 유압 점프의 주요 특성, 수치 모델에 대한 입력 매개변수 및 Ahmed et al.의 참조 실험 조사를 제시합니다. [20], 검증 목적으로 보고되었습니다. 또한, 본 연구에서는 유선의 종방향 프로파일, 캐비티 영역의 유동 패턴, 수평 속도 프로파일, 내부 층의 두께, 베드 전단 응력 계수, TKE 및 에너지 손실과 같은 특성을 조사할 것입니다.

Figure 1. Definition sketch of a submerged hydraulic jump at triangular macroroughnesses.
Figure 1. Definition sketch of a submerged hydraulic jump at triangular macroroughnesses.

Table 2. Effective parameters in the numerical model.

Bed TypeQ
(l/s)
I
(cm)
T (cm)d (cm)y1
(cm)
y4
(cm)
Fr1= u1/(gy1)0.5SRe1= (u1y1)/υ
Smooth30, 4551.62–3.839.64–32.101.7–9.30.26–0.5039,884–59,825
Triangular macroroughnesses30, 454, 8, 12, 16, 20451.62–3.846.82–30.081.7–9.30.21–0.4439,884–59,825
Figure 2. Longitudinal profile of the experimental flume (Ahmed et al. [20]).
Figure 2. Longitudinal profile of the experimental flume (Ahmed et al. [20]).

Table 3. Main flow variables for the numerical and physical models (Ahmed et al. [20]).

ModelsBed TypeQ (l/s)d (cm)y1 (cm)u1 (m/s)Fr1
Numerical and PhysicalSmooth4551.62–3.831.04–3.701.7–9.3
T/I = 0.54551.61–3.831.05–3.711.7–9.3
T/I = 0.254551.60–3.841.04–3.711.7–9.3
Figure 3. The boundary conditions governing the simulations.
Figure 3. The boundary conditions governing the simulations.
Figure 4. Sketch of mesh setup.
Figure 4. Sketch of mesh setup.

Table 4. Characteristics of the computational grids.

MeshNested Block Cell Size (cm)Containing Block Cell Size (cm)
10.551.10
20.651.30
30.851.70

Table 5. The numerical results of mesh convergence analysis.

ParametersAmounts
fs1 (-)7.15
fs2 (-)6.88
fs3 (-)6.19
K (-)5.61
E32 (%)10.02
E21 (%)3.77
GCI21 (%)3.03
GCI32 (%)3.57
GCI32/rp GCI210.98
Figure 5. Time changes of the flow discharge in the inlet and outlet boundaries conditions (A): Q = 0.03 m3/s (B): Q = 0.045 m3/s.
Figure 5. Time changes of the flow discharge in the inlet and outlet boundaries conditions (A): Q = 0.03 m3/s (B): Q = 0.045 m3/s.
Figure 6. The evolutionary process of a submerged hydraulic jump on the smooth bed—Q = 0.03 m3/s.
Figure 6. The evolutionary process of a submerged hydraulic jump on the smooth bed—Q = 0.03 m3/s.
Figure 7. Numerical versus experimental basic parameters of the submerged hydraulic jump. (A): y3/y1; and (B): y4/y1.
Figure 7. Numerical versus experimental basic parameters of the submerged hydraulic jump. (A): y3/y1; and (B): y4/y1.
Figure 8. Velocity vector field and flow pattern through the gate in a submerged hydraulic jump condition: (A) smooth bed; (B) triangular macroroughnesses.
Figure 8. Velocity vector field and flow pattern through the gate in a submerged hydraulic jump condition: (A) smooth bed; (B) triangular macroroughnesses.
Figure 9. Velocity vector distributions in the x–z plane (y = 0) within the cavity region.
Figure 9. Velocity vector distributions in the x–z plane (y = 0) within the cavity region.
Figure 10. Typical vertical distribution of the mean horizontal velocity in a submerged hydraulic jump [46].
Figure 10. Typical vertical distribution of the mean horizontal velocity in a submerged hydraulic jump [46].
Figure 11. Typical horizontal velocity profiles in a submerged hydraulic jump on smooth bed and triangular macroroughnesses.
Figure 11. Typical horizontal velocity profiles in a submerged hydraulic jump on smooth bed and triangular macroroughnesses.
Figure 12. Horizontal velocity distribution at different distances from the sluice gate for the different T/I for Fr1 = 6.1
Figure 12. Horizontal velocity distribution at different distances from the sluice gate for the different T/I for Fr1 = 6.1
Figure 13. Stream-wise velocity distribution for the triangular macroroughnesses with T/I = 0.5 and 0.25.
Figure 13. Stream-wise velocity distribution for the triangular macroroughnesses with T/I = 0.5 and 0.25.
Figure 14. Dimensionless horizontal velocity distribution in the submerged hydraulic jump for different Froude numbers in triangular macroroughnesses.
Figure 14. Dimensionless horizontal velocity distribution in the submerged hydraulic jump for different Froude numbers in triangular macroroughnesses.
Figure 15. Spatial variations of (umax/u1) and (δ⁄y1).
Figure 15. Spatial variations of (umax/u1) and (δ⁄y1).
Figure 16. The shear stress coefficient (ε) versus the inlet Froude number (Fr1).
Figure 16. The shear stress coefficient (ε) versus the inlet Froude number (Fr1).
Figure 17. Longitudinal turbulent kinetic energy distribution on the smooth and triangular macroroughnesses: (A) Y/2; (B) Y/6.
Figure 17. Longitudinal turbulent kinetic energy distribution on the smooth and triangular macroroughnesses: (A) Y/2; (B) Y/6.
Figure 18. The energy loss (EL/E3) of the submerged jump versus inlet Froude number (Fr1).
Figure 18. The energy loss (EL/E3) of the submerged jump versus inlet Froude number (Fr1).

Conclusions

  • 본 논문에서는 유선의 종방향 프로파일, 공동 영역의 유동 패턴, 수평 속도 프로파일, 스트림 방향 속도 분포, 내부 층의 두께, 베드 전단 응력 계수, 난류 운동 에너지(TKE)를 포함하는 수중 유압 점프의 특성을 제시하고 논의했습니다. ) 및 삼각형 거시적 거칠기에 대한 에너지 손실. 이러한 특성은 FLOW-3D® 모델을 사용하여 수치적으로 조사되었습니다. 자유 표면을 시뮬레이션하기 위한 VOF(Volume of Fluid) 방법과 난류 RNG k-ε 모델이 구현됩니다. 본 모델을 검증하기 위해 평활층과 삼각형 거시 거칠기에 대해 수치 시뮬레이션과 실험 결과를 비교했습니다. 본 연구의 다음과 같은 결과를 도출할 수 있다.
  • 개발 및 개발 지역의 삼각형 거시 거칠기의 흐름 패턴은 수중 유압 점프 조건의 매끄러운 바닥과 비교하여 더 작은 영역에서 동일합니다. 삼각형의 거대 거칠기는 거대 거칠기 사이의 공동 영역에서 또 다른 시계 방향 와류의 형성으로 이어집니다.
  • T/I = 1, 0.5 및 0.33과 같은 거리에 대해 속도 벡터 분포는 캐비티 영역에서 시계 방향 소용돌이를 표시하며, 여기서 속도의 크기는 평균 유속보다 훨씬 작습니다. 삼각형 거대 거칠기(T/I = 0.25 및 0.2) 사이의 거리를 늘리면 캐비티 영역에 크기가 다른 두 개의 소용돌이가 형성됩니다.
  • 삼각형 거시조도 사이의 거리가 충분히 길면 흐름이 다음 조도에 도달할 때까지 속도 분포가 회복됩니다. 그러나 짧은 거리에서 흐름은 속도 분포의 적절한 회복 없이 다음 거칠기에 도달합니다. 따라서 거시 거칠기 사이의 거리가 감소함에 따라 마찰 계수의 증가율이 감소합니다.
  • 삼각형의 거시적 거칠기에서, 잠수 점프의 지정된 섹션에서 최대 속도는 자유 점프보다 높은 값으로 이어집니다. 또한, 수중 점프에서 두 가지 유형의 베드(부드러움 및 거친 베드)에 대해 깊이 및 와류 증가로 인해 베드로부터의 최대 속도 거리는 감소합니다. 잠수 점프에서 경계층 두께는 자유 점프보다 얇습니다.
  • 매끄러운 베드의 난류 영역은 게이트로부터의 거리에 따라 생성되고 자유 표면 롤러 영역 근처에서 발생하는 반면, 거시적 거칠기에서는 난류가 게이트 근처에서 시작되어 더 큰 강도와 제한된 스위프 영역으로 시작됩니다. 이는 반시계 방향 순환의 결과입니다. 거시 거칠기 사이의 공간에서 자유 표면 롤러 및 시계 방향 와류.
  • 삼각 거시 거칠기에서 침지 점프의 베드 전단 응력 계수와 에너지 손실은 유입구 Froude 수의 증가에 따라 증가하는 매끄러운 베드에서 발견된 것보다 더 큽니다. T/I = 0.50 및 0.20에서 최고 및 최저 베드 전단 응력 계수 및 에너지 손실이 평활 베드에 비해 거칠기 요소의 거리가 증가함에 따라 발생합니다.
  • 거의 거칠기 요소가 있는 삼각형 매크로 거칠기의 존재에 의해 주어지는 점프 길이와 잠긴 수심 및 꼬리 수심의 감소는 결과적으로 크기, 즉 길이 및 높이가 감소하는 정수조 설계에 사용될 수 있습니다.
  • 일반적으로 CFD 모델은 다양한 수력 조건 및 기하학적 배열을 고려하여 잠수 점프의 특성 예측을 시뮬레이션할 수 있습니다. 캐비티 영역의 흐름 패턴, 흐름 방향 및 수평 속도 분포, 베드 전단 응력 계수, TKE 및 유압 점프의 에너지 손실은 수치적 방법으로 시뮬레이션할 수 있습니다. 그러나 거시적 차원과 유동장 및 공동 유동의 변화에 ​​대한 다양한 배열에 대한 연구는 향후 과제로 남아 있다.

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Flow on the inclined drop with bat-shaped elements: (a) Non-submerged flow

Numerical Methods in Civil Engineering

Rasoul Daneshfaraz*, Ehsan Aminvash**, Silvia Di Francesco***, Amir Najibi**, John Abraham****

토목공학의 수치해석법

Abstract

The main purpose of this study is to provide a method to increase energy dissipation on an inclined drop. Therefore, three types of rough elements with cylindrical, triangular and batshaped geometries are used on the inclined slope in the relative critical depth range of 0.128 to 0.36 and the effect of the geometry of these elements is examined using Flow 3D software. The results showed demonstrate that the downstream relative depth obtained from the numerical analysis is in good agreement with the laboratory results. The application of rough elements on the inclined drop increased the downstream relative depth and also the relative energy dissipation. The application of rough elements on the sloping surface of the drop significantly reduced the downstream Froude number, so that the Froude number in all models ranging from 4.7~7.5 to 1.45~3.36 also decreased compared to the plain drop. Bat-shaped elements are structurally smaller in size, so the use of these elements, in addition to dissipating more energy, is also economically viable.

이 연구의 주요 목적은 경사진 낙하에서 에너지 소산을 증가시키는 방법을 제공하는 것입니다. 따라서 0.128 ~ 0.36의 상대 임계 깊이 범위에서 경사면에 원통형, 삼각형 및 박쥐 모양의 형상을 가진 세 가지 유형의 거친 요소가 사용되며 이러한 요소의 형상의 영향은 Flow 3D 소프트웨어를 사용하여 조사됩니다. 결과는 수치 분석에서 얻은 하류 상대 깊이가 실험실 결과와 잘 일치함을 보여줍니다. 경 사진 낙하에 거친 요소를 적용하면 하류 상대 깊이와 상대 에너지 소산이 증가했습니다. 낙차 경사면에 거친 요소를 적용하면 하류의 Froude 수를 크게 감소시켜 4.7~7.5에서 1.45~3.36 범위의 모든 모델에서 Froude 수도 일반 낙차에 비해 감소했습니다. 박쥐 모양의 요소는 구조적으로 크기가 더 작기 때문에 더 많은 에너지를 분산시키는 것 외에도 이러한 요소를 사용하는 것이 경제적으로도 가능합니다.

Keywords: Downstream depth, Energy dissipation, Froude number, Inclined drop, Roughness elements

Introduction

급수 네트워크 시스템, 침식 수로, 수처리 시스템 및 경사가 큰 경우 흐름 에너지를 더 잘 제어하기 위해 경사 방울을 사용할 수 있습니다. 낙하 구조는 지반의 자연 경사를 설계 경사로 변환하여 에너지 소산, 유속 감소 및 수심 증가를 유발합니다. 따라서 흐름의 하류 에너지를 분산 시키기 위해 에너지 분산 구조를 사용할 수 있습니다. 난기류와 혼합된 물과 공기의 형성은 에너지 소비를 증가 시키는 효과적인 방법입니다. 흐름 경로에서 거칠기 요소를 사용하는 것은 에너지 소산을 위한 알려진 방법입니다. 이러한 요소는 흐름 경로에 배치됩니다. 그들은 종종 에너지 소산을 증가시키기 위해 다른 기하학적 구조와 배열을 가지고 있습니다. 이 연구의 목적은 직사각형 경사 방울에 대한 거칠기 요소의 영향을 조사하는 것입니다.

Fig. 1: Model made in Ardabil, Iran
Fig. 1: Model made in Ardabil, Iran
Fig. 2: Geometric and hydraulic parameters of an inclined drop equipped with roughness elements
Fig. 2: Geometric and hydraulic parameters of an inclined drop equipped with roughness elements
Fig. 3: Views of the incline with (a) Bat-shaped, (b) Cylindrical, (c) Triangular roughness elements
Fig. 3: Views of the incline with (a) Bat-shaped, (b) Cylindrical, (c) Triangular roughness elements
Fig. 4: Geometric profile of inclined drop and boundary conditions with the bat-shape roughness element
Fig. 4: Geometric profile of inclined drop and boundary conditions with the bat-shape roughness element
Fig. 5: Variation of the RMSE varying cell size
Fig. 5: Variation of the RMSE varying cell size
Fig. 6: Numerical and laboratory comparison of the downstream relative depth
Fig. 6: Numerical and laboratory comparison of the downstream relative depth
Fig. 7: Flow profile on inclined drop in discharge of 5 L/s: (a) Without roughness elements; (b) Bat-shaped roughness element; (c) Cylindrical roughness element; (d) Triangular roughness element
Fig. 7: Flow profile on inclined drop in discharge of 5 L/s: (a) Without roughness elements; (b) Bat-shaped roughness element; (c) Cylindrical roughness element; (d) Triangular roughness element
Fig. 8: Relative edge depth versus the relative critical depth
Fig. 8: Relative edge depth versus the relative critical depth
Flow on the inclined drop with bat-shaped elements: (a) Non-submerged flow
Flow on the inclined drop with bat-shaped elements: (a) Non-submerged flow
Fig. 9: Flow on the inclined drop with bat-shaped elements: (b) Submerged flow
Fig. 9: Flow on the inclined drop with bat-shaped elements: (b) Submerged flow
Fig. 10: Relative downstream depth versus the relative critical depth
Fig. 10: Relative downstream depth versus the relative critical depth
Fig. 11: Relative downstream depth versus the relative critical depth
Fig. 11: Relative downstream depth versus the relative critical depth

Conclusions

현재 연구에서 FLOW-3D 소프트웨어를 사용하여 한 높이, 한 각도, 밀도 15% 및 지그재그 배열에서 삼각형, 원통형 및 박쥐 모양의 형상을 가진 세 가지 유형의 거칠기 요소를 사용하여 경사 낙하 수리학적 매개변수에 대한 거칠기 요소 형상의 영향 평가되었다. VOF 방법을 사용하여 자유 표면 흐름을 시뮬레이션하고 초기에 3개의 난류 모델 RNG, k-ɛ 및 kω를 검증에 사용하고 이를 검토한 후 RNG 방법을 사용하여 다른 모델을 시뮬레이션했습니다. 1- 수치 결과에서 얻은 부드러운 경사 방울의 하류 상대 깊이는 실험실 데이터와 매우 좋은 상관 관계가 있으며 원통형 요소가 장착 된 경사 방울의 상대 에지 깊이 값이 가장 높았습니다. 2- 하류 상대깊이는 임계상대깊이가 증가함에 따라 상승하는 경향을 나타내어 박쥐형 요소를 구비한 경사낙하와 완만한 경사낙하가 각각 하류상대깊이가 가장 높고 가장 낮았다. 3- 하류 깊이의 증가로 인해 상대적 임계 깊이가 증가함에 따라 상대적 에너지 소산이 감소합니다. 한편, 가장 높은 에너지 소산은 박쥐 모양의 요소가 장착된 경사 낙하와 관련이 있으며 가장 낮은 에너지 소산은 부드러운 낙하와 관련이 있습니다. 삼각형, 원통형 및 박쥐 모양의 거친 요소가 장착된 드롭은 부드러운 드롭보다 각각 65%, 76% 및 85% 더 많은 흐름 에너지를 소산합니다. 4- 낙차의 경사면에 거친 요소를 적용하여 다운 스트림 Froude 수를 크게 줄여 4.7 ~ 7.5에서 1.45 ~ 3.36까지의 모든 모델에서 Froude 수가 부드러운 낙하에 비해 감소했습니다. 또한, 다른 원소보다 부피가 작은 박쥐 모양의 거칠기의 부피로 인해 이러한 유형의 거칠기를 사용하는 것이 경제적입니다.

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Abb. 3 Detail des Rechens am Vorversuch zum Seilrechen – Blick in Fließrichtung

Implementation of an angled trash rack in the 3D-numerical simulation with FLOW-3D

Abstract

Sebastian Krzyzagorski · Roman Gabl · Jakob Seibl · Heidi Böttcher · Markus Aufleger
Online publiziert: 17. Februar 2016
© Die Autor(en) 2016. Dieser Artikel ist auf Springerlink.com mit Open Access verfügbar.

지난 몇 년 동안 과학자와 엔지니어는 기초 연구와 유압 구조 계획에 3D 수리적 흐름 시뮬레이션을 점점 더 많이 사용해 왔다. 그러나 수력발전소 취수장 앞의 쓰레기통은 수치 시뮬레이션에 있어 특별한 문제를 나타낸다. 그 이유는 다른 건축 요소들에 비해 trash rack bars들의 기하학적 구조가 특히 단편화되었기 때문이다. 폐기물 랙 손실을 FLOW-3D로 3D 수리적 시뮬레이션에 포함시키기 위한 대안적 접근법으로 배플을 사용할 수 있다. 월디 외 연구진(Exsterreichische Wasser- und Abfallwichtschaft 67:1–2, 2015)은 그러한 배플이 쓰레기 수거함의 손실을 모형화하는 유망한 방법임을 입증했다. 서로 다른 개념의 이러한 비교는 계산면을 따라 그리드 방향을 갖는 수직 쓰레기장으로 제한되었다. 실제 논문은 각이 진 쓰레기 보관대의 배플을 이용하여 쓰레기 보관대 손실을 모델링하는 것에 초점을 맞추고 있으며, 따라서 월디 외 연구소의 조사를 업그레이드한다

Over the last years, scientists and engineers have used more and more 3D-numerical flow simulations for basic research and the planning of hydraulic constructions. However, trash racks in front of the intakes of hydroelectric power plants represent a particular problem for numerical simulations. The reason for this is the especially fragmented geometry of the trash rack bars in comparison to other construction elements. As an alternative approach to include trash rack losses into a 3D-numerical simulation with FLOW-3D a baffle can be used. Waldy et al. (Österreichische Wasser- und Abfallwirtschaft 67:1–2, 2015) demonstrated that such a baffle is a promising method to model the losses at trash racks. These comparisons of different concepts were limited to a vertical trash rack, which had its grid orientation along the computational plane. The actual paper focuses on the modelling of the trash rack losses by means of a baffle at an angled trash rack and thus upgrades the survey of Waldy et al. (Österreichische Wasser- und Abfallwirtschaft 67:1–2, 2015).

Vertikal geneigte Rechenstäbe mit Winkel a nach Definition von  Meusburger (2002) und b Seilrechen mit  Winkel d
Vertikal geneigte Rechenstäbe mit Winkel a nach Definition von Meusburger (2002) und b Seilrechen mit Winkel d
Abb. 2 Modellgeometrie, Grundriss (GR) und Schnitte für den geraden Rechen und exemplarisch der GR für den 30° geneigten  Rechen – Einheiten in [m]
Abb. 2 Modellgeometrie, Grundriss (GR) und Schnitte für den geraden Rechen und exemplarisch der GR für den 30° geneigten Rechen – Einheiten in [m]
Abb. 3 Detail des Rechens am Vorversuch zum Seilrechen – Blick in Fließrichtung
Abb. 3 Detail des Rechens am Vorversuch zum Seilrechen – Blick in Fließrichtung
3D-Ansicht der Nullvariante, geneigter Rechen, d=30°, Netz N4
3D-Ansicht der Nullvariante, geneigter Rechen, d=30°, Netz N4
 Zellenweise Auswertung der Wasserspiegelhöhen ohne Interpolation mit  MATLAB für die Nullvariante, geneigter Rechen, d=30°, Netz N4
Zellenweise Auswertung der Wasserspiegelhöhen ohne Interpolation mit MATLAB für die Nullvariante, geneigter Rechen, d=30°, Netz N4
Auswertung Einfluss der Rechenneigung für Netz N4
Auswertung Einfluss der Rechenneigung für Netz N4
Grundriss mit tiefengemittelten Geschwindigkeiten und Geschwindigkeitsvektoren, geneigter Rechen, d=30°, Netz N
Grundriss mit tiefengemittelten Geschwindigkeiten und Geschwindigkeitsvektoren, geneigter Rechen, d=30°, Netz N
FLOW-3D (x) Workflow

Optimizing Design Performance with Baffle Placement

배플 배치로 설계 성능 최적화

최적화 목표

배플이 있는 액체 저장 탱크의 슬로시 댐핑

최적화 과제

사용자가 슬로싱 시뮬레이션을 여러번 반복하여 대형 원통형 탱크에서 댐핑을 최대화하는 최적의 링 배플 위치를 찾을 수 있는 워크플로를 생성합니다. 여기에서 시뮬레이션된 사례는 Maleki 및 Ziyaeifar (2008)1 의 물리적 실험을 기반으로합니다 .

액체 저장 탱크 개략도

최적화 솔루션

시뮬레이션은 수직으로 배치된 원통형 탱크에서 0.6m의 유체 높이에서 처음에 수평에서 5도 배치된 유체의 슬로싱의 자유 붕괴를 나타냅니다. 링 배플의 위치는 z 방향으로 변환할 수 있습니다. 목표는 가장 많은 양의 슬로시 댐핑을 발생시키는 배플의 위치를 ​​찾는 것입니다. 각 시뮬레이션은 12 개의 CPU 코어에서 약 10 분 동안 실행됩니다.

예산 범위에서 30 회 반복 또는 허용되는 시뮬레이션 반복 횟수가 지정됩니다. FLOW-3D (x) 는 30 개의 시뮬레이션을 실행하여 시스템의 동작을 나타내는 반응 표면을 생성합니다. 이를 통해 최상의 솔루션을 찾을 수 있습니다.  

FLOW-3D (x) 워크 플로우

FLOW-3D (x) 는 노드를 사용하여 최적화를 위한 자동화된 워크 플로를 구성합니다. 이 워크 플로우를 시작할 때 z 방향의 초기 배플 위치가 제공됩니다. 배플 위치는 규정된 경계 사이에서 수직으로 이동하도록 허용됩니다. 그런 다음 각 시뮬레이션은 반복 시뮬레이션을 실행하는 FLOW-3D 노드로 공급됩니다. 시뮬레이션 결과는 감쇠 계산을 수행하는 계산기 노드에 연결됩니다. 그런 다음 최적화 엔진은 지속적으로 개선되는 응답 표면을 기반으로 배플의 또 다른 z 좌표를 선택하고 다른 시뮬레이션 실행을 계속합니다.  

FLOW-3D (x) 최적화 워크 플로우 배플 성능 설계

결과

FLOW-3D(x)의 내장 데이터 분석 도구를 사용하여 결과를 그래픽으로 표시하면 0.55m의 배플 높이가 최대 댐핑 비율을 제공한다는 것을 알 수 있습니다. 시뮬레이션 및 반복 설계 기능은 모두 프로그램과 함께 자동화됩니다. 또한 각 시뮬레이션의 영상과 비디오를 출력으로 설정할 수 있습니다.

성능 설계 최적화-슬로 싱

References

1Maleki, A. and Ziyaeifar, M., 2008. Sloshing damping in cylindrical liquid storage tanks with baffles. Journal of Sound and Vibration, 311(1-2), pp.372-385.

FLOW-3D (x)

FLOW-3D (x)

Achieve Better CFD Workflows with FLOW-3D (x)

FLOW-3D(x) 는 자동화, 최적화 및 배치 처리를 CFD 워크 플로에 연결하여 CFD를 수행하는 방식을 크게 변화시킵니다. FLOW-3D(x)를 사용하면 자동화 및 최적화 워크 플로우를 그래픽적이고 직관적으로 구축 할 수 있을 뿐만 아니라 Solidworks, Rhino 및 Excel과 같은 외부 프로그램을 연결하여 시뮬레이션에 정보를 동적으로 제공할 수 있습니다. 

설계 매개 변수 공간을 실행하거나 실험 설계에 관심이 있거나 최상의 성능을 위해 형상 부품을 최적화 하는 경우 FLOW-3D(x)를 사용하면 배치 워크 플로우를 구성하고 고급 매개 변수 형상 연구를 수행하며 자동화 및 최적화를 결합하여 신속하게 설계 목표를 충족하고 최적의 해결 방안에 도달할 수 있습니다.

FLOW-3D (x) Case Studies

  


FLOW-3D (x) Features

OPTIMIZATION

  • 최적의 설계 매개 변수를 식별하여 제품 성능을 향상시킵니다.

WORKFLOW AUTOMATION

  • 일반적인 시뮬레이션 작업 자동화 : 사전 정의된 매개 변수 세트를 실행하고 시뮬레이션 결과를 추출하고 그래픽 출력을 생성합니다.

SIMULATION CALIBRATION

  • 원하는 결과를 얻는데 필요한 시뮬레이션 매개 변수를 식별합니다.

PARAMETER SENSITIVITY

  • 입력 매개 변수에 대한 시뮬레이션의 민감도를 결정합니다.

PYTHON INTEROPERABILITY

  • Python 스크립트를 실행하여 POST 처리 및 입력 사용자 지정을 제공합니다.

EXPERIMENTAL/LAB RESULTS

  • 기존 실험실 데이터에 대한 반응 표면을 만듭니다.

CAD PLUGINS

  • FLOW-3D (x) 내에서 직접 매개 변수화 된 CAD 모델과 상호 작용 합니다.
  • Solidworks, Rhino/Grasshopper, PTC Creo, NX, Spaceclaim, Catia 및 Autodesk Inventor.

DISTRIBUTED SOLVING

  • 최대의 효율성을 위해 원격 Windows 및 Linux 워크스테이션에서 시뮬레이션을 실행할 수 있습니다.


MICROSOFT EXCEL PLUGIN

  • Excel의 강력한 기능을 활용할 수 있습니다.
Mixing Tank with FLOW-3D

CFD Stirs Up Mixing 일반

CFD (전산 유체 역학) 전문가가 필요하고 때로는 실행하는데 몇 주가 걸리는 믹싱 시뮬레이션의 시대는 오래 전입니다. 컴퓨팅 및 관련 기술의 엄청난 도약에 힘 입어 Ansys, Comsol 및 Flow Science와 같은 회사는 엔지니어의 데스크톱에 사용하기 쉬운 믹싱 시뮬레이션을 제공하고 있습니다.

“병렬화 및 고성능 컴퓨팅의 발전과 템플릿화는 비전문 화학 엔지니어에게 정확한 CFD 시뮬레이션을 제공했습니다.”라고 펜실베이니아  피츠버그에있는 Ansys Inc.의 수석 제품 마케팅 관리자인 Bill Kulp는 말합니다 .

흐름 개선을위한 실용적인 지침이 필요하십니까? 다운로드 화학 처리의 eHandbook을 지금 흐름 도전 싸우는 방법!

예를 들어, 회사는 휴스턴에있는 Nalco Champion과 함께 프로젝트를 시작했습니다. 이 프로젝트는 시뮬레이션 전문가가 아닌 화학 엔지니어에게 Ansys Fluent 및 ACT (분석 제어 기술) 템플릿 기반 시뮬레이션 앱에 대한 액세스 권한을 부여합니다. 새로운 화학 물질을위한 프로세스를 빠르고 효율적으로 확장합니다.

Giving Mixing Its Due

“화학 산업은 CFD와 같은 계산 도구를 사용하여 많은 것을 얻을 수 있지만 혼합 프로세스는 단순하다고 가정하기 때문에 간과되는 경우가 있습니다. 그러나 최신 수치 기법을 사용하여 우수한 성능을 달성하는 흥미로운 방법이 많이 있습니다.”라고 Flow Science Inc. , Santa Fe, NM의 CFD 엔지니어인 Ioannis Karampelas는 말합니다 .

이러한 많은 기술이 회사의 Flow-3D Multiphysics 모델링 소프트웨어 패키지와 전용 포스트 프로세서 시각화 도구 인 FlowSight에 포함되어 있습니다.

“모든 상업용 CFD 패키지는 어떤 형태의 시각화 도구와 번들로 제공되지만 FlowSight는 매우 강력하고 사용하기 쉽고 이해하기 쉽게 설계되었습니다. 예를 들어, 프로세스를 재 설계하려는 엔지니어는 다양한 설계 변경의 효과를 평가하기 위해 매우 직관적인 시각화 도구가 필요합니다.”라고 그는 설명합니다.

이 접근 방식은 실험 측정을 얻기 어려운 공정 (예 : 쉽게 측정 할 수없는 매개 변수 및 독성 물질의 존재로 인해 본질적으로 위험한 공정)을 더 잘 이해하고 최적화하는데 특히 효과적입니다.

동일한 접근 방식은 또한 믹서 관련 장비 공급 업체가 고객 요구에 맞게 제품을보다 정확하게 개발하고 맞춤화하는 데 도움이되었습니다. “이는 불필요한 프로토 타이핑 비용이나 잠재적 인 과도한 엔지니어링을 방지합니다. 두 가지 모두 일부 공급 업체의 문제였습니다.”라고 Karampelas는 말합니다.

CFD 기술 자체는 계속해서 발전하고 있습니다. 예를 들어, 수치 알고리즘의 관점에서 볼 때 구형 입자의 상호 작용이 열 전달을 적절하게 모델링하는 데 중요한 다양한 문제에 대해 이산 요소 모델링을 쉽게 적용 할 수있는 반면, LES 난류 모델은 난류 흐름 패턴을 정확하게 시뮬레이션하는 데 이상적입니다.

컴퓨팅 리소스에 대한 비용과 수요에도 불구하고 Karampelas는 난류 모델의 전체 제품군을 제공 할 수있는 것이 중요하다고 생각합니다. 특히 LES는 이미 대부분의 학계와 일부 산업 (예 : 전력 공학)에서 선택하는 방법이기 때문입니다. .

그럼에도 불구하고 CFD의 사용이 제한적이거나 비실용적 일 수있는 경우는 확실히 있습니다. 여기에는 나노 입자에서 벌크 유체 증발을 모델링하는 것과 같이 관심의 규모가 다른 규모에 따라 달라질 수있는 문제와 중요한 물리적 현상이 아직 알려지지 않았거나 제대로 이해되지 않았거나 아마도 매우 복잡한 문제 (예 : 모델링)가 포함됩니다. 음 펨바 효과”라고 Karampelas는 경고합니다.

반면에 더욱 강력한 하드웨어와 업데이트 된 수치 알고리즘의 출현은 CFD 소프트웨어를 사용하여 과다한 설계 및 최적화 문제를 해결하기위한 최적의 접근 방식이 될 것이라고 그는 믿습니다.

“복잡한 열교환 시스템 및 새로운 혼합 기술과 같이 점점 더 복잡한 공정을 모델링 할 수있는 능력은 가까운 장래에 가능할 수있는 일을 간단히 보여줍니다. 수치적 방법 사용의 주요 이점은 설계자가 상상력에 의해서만 제한되어 소규모 믹서에서 대규모 반응기 및 증류 컬럼에 이르기까지 다양한 화학 플랜트 공정을 최적화 할 수있는 길을 열어 준다는 것입니다. 실험적 또는 경험적 접근 방식은 항상 관련성이 있지만 CFD가 미래의 엔지니어를위한 선택 도구가 될 것이라고 확신합니다.”라고 그는 결론을 내립니다.



Seán Ottewell은 Chemical Processing의 편집장입니다. sottewell@putman.net으로 이메일을 보낼 수 있습니다 .

기사 원문 : https://www.chemicalprocessing.com/articles/2017/cfd-stirs-up-mixing/

FLOW-3D 용어 사전 테이블

FLOW-3D Glossary | FLOW-3D 용어 사전

FLOW-3D 용어 사전 / 용어 설명

FLOW-3D 용어 사전 테이블
FLOW-3D 용어 사전 테이블

FLOW-3D 용어 사전 / 용어 설명

Drift Flux

드리프트 모델은 밀도가 서로 다른 두 혼합 유체 구성 요소의 상대적 흐름을 설명합니다. 구성 요소는 상이 다를 수도 있고, 상이 같지만(불가침) 유체가 다를 수도 있습니다. 분산된 위상 입자 크기가 클 경우 드리프트 모델의 적용성에 대한 제한이 존재할 수 있습니다. 이러한 제한은 일반적으로 메쉬 셀 크기의 10% 미만으로 분산된 위상 입자 크기를 유지함으로써 방지할 수 있습니다.

배플

얇은 형상 조각을 나타내는데 사용되는 2 차원 개체입니다. 이들은 전처리기에 의해 셀면으로 이동되고 유체의 흐름을 부분적으로 또는 완전히 차단하는 역할을 합니다. 배플은 지정된 열 전달 계수를 가질 수 있으며 배플을 통과하는 양(플럭스 표면)을 측정하는 데 사용할 수 있습니다.

Two-dimensional objects that are used to represent thin pieces of geometry. They are moved by the preprocessor to cell faces and act to partially, or completely block the flow of fluid. Baffles can have heat transfer coefficients specified and can be used to measure quantities that pass through them (a flux surface).

경계 조건

도메인의 범위에서 솔루션을 정의합니다. 경계 위치에서 흐름의 실제 상태를 나타내는 경계 조건을 선택하는 것이 중요합니다.

Defines the solution at the extents of the domain. It is important to choose boundary conditions that represent the true condition of the flow at the boundary location.

CFD

CFD (Computational Fluid Dynamics)는 수치 솔루션을 통해 컴퓨터의 유체 흐름을 시뮬레이션 하는 유체 역학의 한 분야입니다.

Computational Fluid Dynamics (CFD), the branch of fluid mechanics dedicated to simulating the flow of fluid on a computer via numerical solutions.

Complements

Complements를 정의합니다. 예를 들어, 솔리드 구의 complements는 솔리드 재료로 둘러싸인 구형 구멍입니다.

The inverse of a shape defines the complement. For example, the complement of a solid sphere is a spherical hole surrounded by solid material.

Client

클라이언트 컴퓨터는 자신이 FLOW-3D를 실행하고 있지만, FLOW-3D 소프트웨어 라이선스는 다른 컴퓨터 (서버 컴퓨터)에서 획득하는 컴퓨터를 의미합니다.

A client machine is a computer that runs FLOW-3D  but acquires the software license from a different machine (the server machine)

Components

Components는 공간의 개체를 정의하며 하위 구성 요소로 구성됩니다. 구성 요소는 열 전도율, 비열 및 표면 거칠기와 같은 재료 특성을 가질 수 있습니다.

Components define objects in space and are comprised of subcomponents. A component can have material properties such as thermal conductivity, specific heat and surface roughness.

Custom result

시뮬레이션 중 또는 완료 후 사용자가 생성한 데이터를 그래픽으로 표시합니다. 생성하려면 사용자가 flsgrf결과 파일을 연 다음 플로팅 매개 변수(예 : 플로팅 할 도메인 부분, 플로팅 할 수량 등)를 선택해야 합니다.

Graphical displays of data generated by the user during the simulation or after it has completed. To generate, the user must open an flsgrf results file and then select the plotting parameter (e.g., portion of domain to plot, quantity to plot, etc.).

Domain

지배 방정식을 풀 영역입니다. 이것은 메쉬의 범위에 의해 정의됩니다.

The region in which the governing equations are to be solved. This is defined by the extents of the mesh.

Diagnostics

전 처리기 및 솔버의 진행 상황과 오류 및 경고에 대한 정보가 포함된 파일 세트입니다.

A suite of files that contain information on the progress of the preprocessor and solver as well as errors and warnings.

EPSI

압력/연속 반복이 어느 지점에서 수렴되는지를 결정하는데 사용된 수렴 기준입니다. 기본 숫자 설정을 사용하면 이 값은 FLOW-3D에 의해 자동으로 계산되며 시간 단계가 증가함에 따라 작아집니다.

The convergence criterion that was used to determine at what point the pressure/continuity iterations have converged. With the default numerical settings, this value is automatically computed by FLOW-3D  and becomes smaller as the time step increases.

Existing result

prpplt.* 또는 flsplt.* 파일은 전처리 종료 솔버 실행 종료시 또는 자동으로 생성되는 플롯 파일입니다.

A plot file that is automatically created, either at the end of preprocessing or the end of the solver run- prpplt.* or flsplt.*.

F3D_HOME

FLOW-3D 프로그램 파일이 있는 디렉토리를 정의하는 환경 변수.

Environment variable that defines the directory where the FLOW-3D  program files are located.

Floating license

FLOW-3D는 서버 시스템에 라이센스를 액세스하는 각 클라이언트 컴퓨터와 컴퓨터 네트워크에서 실행합니다. 허용하는 라이센스 최대 동시 시뮬레이션 수는 구매한 솔버 토큰 수에 의해 제한됩니다.

A license that allows FLOW-3D  to be run on a network of computers with each client machine accessing the license on a server machine. The maximum number of concurrent simulations is limited by the number of solver tokens purchased.

Flsgrf file

솔버가 생성한 결과 파일. 이 파일은 사전에 정의된 시간 간격으로 생성된 정보를 포함하며 그래픽 디스플레이를 생성하는 데 사용됩니다. 사용자 정의 플로팅 중에 포스트 프로세서에서 사용합니다.

Results file produced by the solver. This file contains information produced at predefined time intervals and is used to produce graphical displays. Used by the postprocessor during custom plotting.

Flsplt file

솔버가 자동으로 생성한 플롯 파일입니다. 이 파일에는 시뮬레이션의 히스토리 데이터, 메시 등에 대한 기본 정보와의 $GRAFIC 이름 목록에 사전 정의된 그래픽 요청이 포함되어 prepin.* 파일 안에 있습니다.

Plot file produced automatically by the solver. This file contains basic information on history data, mesh, etc. from the simulation as well as any pre-defined graphics requests in the $GRAFIC namelist in prepin.*.

Fluid #1 surface area

선택한 길이 단위의 자유 표면 영역을 제곱 됩니다. 인터페이스가 예리한 문제에만 해당됩니다.

The free-surface area in the chosen length units squared. This is only relevant for problems with a sharp interface.

Fluid thermal energy

영역에 존재하는 모든 유체에 포함된 총 열 에너지 (에너지 전송이 켜져 있는 시뮬레이션에만 해당).

The total thermal energy contained by all the fluid present in the domain (relevant only for simulations with energy transport turned on).

Free surface

유체와 유체 사이의 인터페이스. FLOW-3D에서 이 인터페이스는 전단이 없는 것으로 가정되며, 이는 빈 공간에 있는 가스가 유체에 무시할 수 있는 트랙션을 발휘함을 의미한다.

The interface between fluid and void. In FLOW-3D , this interface is assumed to be shear-free, meaning that any gas in the void space exerted negligible traction on the fluid.

GUI

” Graphical User Interface”.  GUI는 사용자가 FLOW-3D를 제어할 수 있는 그래픽 패널, 대화 상자 및 창을 제공합니다.

“Graphical User Interface”. The GUI presents the graphical panels, dialog boxes and windows that allow the user to control FLOW-3D .

Iteration count

각 시간 단계에서 필요한 압력/연속 반복 횟수입니다. 압력/연속성 반복은 유체 볼륨이 유지되도록 하고 유체 전체에서 올바른 압력을 계산하는 데 필요합니다.

The number of pressure/continuity iterations required at each time step. The pressure/continuity iterations are necessary to ensure that the fluid volume is maintained and to compute the correct pressure throughout the fluid.

License file

사용자가 FLOW-3D 를 실행할 수 있도록 암호화된 정보가 포함된 Flow Science에서 제공하는 전자 파일 입니다.

Electronic file provided by Flow Science that contains encrypted information enabling the user to run FLOW-3D .

License server

플로팅 라이센스 시스템의 작동을 활성화하기 위해 FLEXlm 라이센스 소프트웨어가 설치된 시스템. FLOW-3D는 License Server에 설치할 필요가 없습니다.

Computer on which the FLEXlm licensing software is installed to enable the operation of a floating license system. FLOW-3D  does not need to be installed on the license server.

Licensing

FLOW-3D 실행을 제어하는 ​​FLEXlm 소프트웨어.

FLEXlm software that controls the running of FLOW-3D .

Max. residual

압력/연속성 반복의 최종 반복에서 연속성 방정식의 실제 발산. 이 값은 메시지가 나타나지 않는 한 일반적으로 epsi보다 작습니다 .

The actual divergence of the continuity equation on the final iteration of the pressure/continuity iterations. This value is usually smaller than epsi unless the message, pressure iteration did not converge in xxxx iterations appears.

Mean kinetic energy

모든 계산 셀의 운동 에너지의 합을 도메인에 존재하는 총 유체 질량으로 나눈 값입니다. 이 양이 시간이 지남에 따라 변하지 않으면 정상 상태에 도달했음을 나타내는 좋은 지표입니다.

The sum of kinetic energy of all the computational cells, divided by the total mass of fluid present in the domain. When this quantity ceases to change over time, it is a good indicator that steady-state has been reached.

Node-locked license

특정 컴퓨터에 고정된 라이센스. 노드 잠금 라이센스는 네트워크를 통해 액세스 할 수 없으므로 일반적으로 모든 작업을 한 컴퓨터에서 수행해야하는 경우에만 사용됩니다.

A license that is locked to a particular computer. A node-locked license cannot be accessed across a network, and so is typically only used when all work is to be done on one computer.

Non-inertial reference frame

가속화되는 참조 프레임. 비 관성 참조 프레임은 움직이는 컨테이너를 모방하는 데 사용할 수 있습니다.

A frame of reference that is accelerating. A non-inertial reference frame can be used to mimic a moving container.

Pltfsi

1D 및 2D 플롯을 생성하는 FLOW-3D에 포함된 그래픽 디스플레이 프로그램.

Graphics display program included with FLOW-3D  that produces 1D and 2D plots.

Postprocessor

FLOW-3D 내의 Postprocessor 프로그램은 FLOW-3D 또는 타사 시각화 프로그램에서 읽을 수 있는 데이터 파일을 생성하거나 타사 소프트웨어 프로그램에서 읽을 텍스트 데이터를 생성하는 솔버 출력 데이터를 처리하는 프로그램입니다.

The program within FLOW-3D  that processes the solver output data to produce data files that can be read by FLOW-3D ’s or third-party’s visualization programs, or produce text data to be read by third party software programs.

Prepin file

FLOW-3D 시뮬레이션을 실행하는데 필요한 모든 정보가 포함된 텍스트 파일 입니다. GUI를 사용하거나 텍스트 편집기를 사용하여 수동으로 작성할 수 있습니다.

Text file that contains all of the information necessary to create a FLOW-3D  simulation. It can be created using the GUI or manually with a text editor.

Preprocessor

솔버의 실행을 준비하기 위해 입력 파일을 기반으로 메쉬 및 초기 조건을 생성하는 FLOW-3D 내의 프로그램 입니다.

The program within FLOW-3D  that generates the mesh and initial conditions based on the input file in preparation for the running of the solver.

Prpgrf file

전처리기에 의해 생성된 결과 파일로 전 처리기의 정보를 포함하며 후 처리기에서 사용자 플롯을 생성하는 데 사용할 수 있습니다. 이 파일은 미리보기 버튼을 선택하거나 시뮬레이션에서 사전 프로세서(runpre 사용)를 실행하는 경우에만 실행됩니다.

Results file produced by the preprocessor. Contains information from the preprocessor and can be used by the postprocessor to create custom plots. This file is produced only when the Preview button is selected or if only the pre-processor is run on the simulation (using runpre).

Prpplt file

전처리기에 의해 자동으로 생성된 파일을 플롯 합니다. 메시, 구성 요소, 초기 조건 및 재료 특성에 대한 정보가 포함되어 있습니다.

Plot file produced automatically by the preprocessor. Contains information on meshing, components, initial conditions and material properties.

Restart simulation

이전 시뮬레이션에서 계속되는 시뮬레이션입니다. 이전 시뮬레이션의 결과는 다시 시작 시뮬레이션을 위한 초기 조건 및 (선택적으로) 경계 조건을 생성하는 데 사용됩니다.

A simulation which continues from a previous simulation. The results from the previous simulation are used to generate the initial conditions and (optionally) boundary conditions for the restart simulation.

Server

라이센스 서버를 호스팅하는 시스템

The machine that hosts the license server.

Stability limit

각 시간 단계에서 사용할 수 있는 최대 시간 단계. 더 큰 시간 단계는 수치적 불안정성과 비물리적 결과로 이어질 것이다.

The maximum time step that can be used during each time step. A larger time step will lead to numerical instabilities and nonphysical results.

STL (Stereolithography) File

.STL 파일 형식은 일련의 삼각형이 있는 솔리드 모델의 표면에 근접한 표준 데이터 전송 형식이다. 삼각형은 가장자리에서 결합해야 하며 일관된 방향을 가리키는 정규식이 있어야 한다.

The .STL file format is a standard data transmission format that approximates the surfaces of a solid model with a series of triangles. The triangles must join at the edges and must have normals that point in a consistent direction.

Solid fraction

응고된 영역의 유체 분율 (응고 모델이 켜져 있는 시뮬레이션에만 해당).

The fraction of fluid in the domain that has become solidified (relevant only for simulations where the solidification model has been turned on).

Solver

입력 파일에 정의된 흐름 문제를 시뮬레이션하는 방정식을 계산하는 FLOW-3D 내의 솔버 프로그램 입니다.

The program within FLOW-3D  that solves the system of equations that simulate the flow problem defined in the input file.

STL Viewer

스테레오리소그래피(STL) 파일을 표시하는 특수 유틸리티입니다. STL 파일은 CAD 소프트웨어로 제작되며 3 차원 객체의 표면을 형성하는 많은 삼각형으로 구성됩니다. 의 STL 뷰어 FLOW-3D는 메인 메뉴에서 유틸리티/STL 뷰어를 클릭하여 GUI를 통해 액세스 할 수 있습니다. 그러면 뷰어가 별도의 창에서 열립니다. 메쉬 및 형상 탭에서 STL 파일을 열고 볼 수도 있습니다.

A special utility that displays stereolithography (STL) files. STL files are produced by CAD software and are composed of many triangles that form the surface of a three-dimensional object. The STL Viewer in FLOW-3D  is accessible via the GUI by clicking Utilities/STL Viewer in the main menu. This causes the viewer to open in a separate window. STL files can also be opened and viewed in the Meshing and Geometry tab.

Subcomponents

하위 구성 요소는 구성 요소라고하는 더 큰 모양을 형성하기 위해 결합할 수 있는 기하학적 모양입니다. 하위 구성 요소는 재료를 추가하거나 (고체로) 다른 하위 구성 요소에서 재료를 제거하거나 (구멍으로) 또는 모양 외부에 재료를 추가하도록 정의할 수 있습니다.

Subcomponents are geometric shapes that can be combined to form larger shapes, called components. A subcomponent can be defined to add material (as solids), remove material from other subcomponents (as holes), or add material outside of the shape (as a complement).

Time-step size

계산에 사용된 실제 시간 단계. 이 값은 안정성 한계와 같거나 작을 수 있습니다.

The actual time step used in the computation. This value can be equal to or less than the stability limit.

Units

Units are based upon the values set for the physical properties. Items such as mesh block extents and cell lengths automatically conform to the units used for setting these physical properties.

단위는 물리적 특성에 설정된 값을 기반으로 합니다. 메쉬 블록 범위 및 셀 길이와 같은 항목은 이러한 물리적 속성을 설정하는 데 사용되는 단위를 자동으로 따릅니다.

Volume error (%)

주어진 시간에 도메인에 존재하는 총 유체의 백분율로 설명되지 않은 유체 부피의 백분율을 의미합니다. 따라서 단순히 총 부피가 작기 때문에 유체가 시스템 밖으로 배출되는 시뮬레이션에서 큰 비율의 부피 오류가 발생할 수 있습니다.

The percentage of fluid volume not accounted for as a percentage of the total fluid present in the domain at a given time. Therefore, a large percentage volume error can occur for simulations where fluid is draining out of the system simply because the total volume present is small.

Volume of fluid #1

선택한 길이 단위로 입방체에 존재하는 유체 #1의 총 부피입니다. 2 유체 문제의 경우, 유체 #2의 부피는 항상 도메인 부피에서 유체 #1의 부피를 뺀 값입니다.

The total volume of fluid #1 present in the system, in the chosen length units cubed. For two-fluid problems, the volume of fluid #2 is always the domain volume minus the volume of fluid #1.

Wall shear stress

FLOW-3D 옵션은 벽면 및 객체 인터페이스에서 전단 응력 계산을 켜거나 끌 수 있도록 해줍니다. “no-slip” 인터페이스의 효과를 모델링 하려면 벽면 전단 응력을 켜야 합니다.

The FLOW-3D  option that allows the user to turn on or off the computation of shear stress at wall and object interfaces. Wall shear stress must be turned on to model the effect of “no-slip” interfaces.

Workspace

작업 공간은 시뮬레이션 프로젝트를 위한 파일 컨테이너입니다. 작업 공간은 사용자가 FLOW-3D 뿐만 아니라 하드 드라이브에서도 작업을 구성하는 데 도움이 됩니다.

A workspace is a file container for simulation projects. Workspaces help the user organize their work, not only within FLOW-3D , but also on their hard drive.

FLOW-3D 및TruVOF는 미국 및 기타 국가에서 등록 상표입니다.

FLOW-3D 기술자료로 이동

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FLOW-3D 온라인 교육

FLOW-3D Training Modules

FLOW-3D GUI PART 1 OF THE FLOW-3D V12.0 TRAINING SERIES

FLOW-3D GUI

  • Introduction to FLOW-3D graphical user interface
  • Simulation Manager Tab
  • Portfolio
  • Running Simulations and the Queue
  • Runtime Diagnostics: Text Output
  • Runtime Diagnostics: Plots
  • Runtime Controls
  • FLOW-3D File Structure
    Review the important files that are created when running simulations in FLOW-3D. Access the simulation files through a link on the Simulation Manager Tab. Identify the important setup and solver outputs files

모델 설정 탭

  • Introduction to the Model Setup TabIntroduction to the Model Setup Tab including an orientation to its layout and how to access model inputs though the dock widgets on the process toolbar. Options for customizing the layout of the process toolbar are also reviewed.
  • Navigating the 3D ViewportLearn the basic controls for navigating the 3D viewport. This includes mouse controls, toolbar shortcuts, saving views, and moving the pivot point.
  • Other Menu/Toolbar Navigation Options
  • Working with Dock Widget Inputs
  • Model DependenciesRecognize and understand dock widget input dependencies.
Model Setup Tab PART 2 OF THE FLOW-3D V12.0 TRAINING SERIES
Global Settings PART 3 OF THE FLOW-3D V12.0 TRAINING SERIES

전역 설정

  • Global Dock Widget Overview
  • Pressure Type
  • Finish Time
  • Finish Options: Additional Finish Condition
  • Finish Options: Active Simulation ControlDefine a logical condition to stop the simulation using active simulation control.
  • Restart OptionsHow to manually define the Restart options to continue running a previously completed simulation.
  • Version OptionsDefine the Version options to specify the solver version and the number of processors used when starting a new simulation run.

물리 모델

  • Physics Dock Widget OverviewDescription of the available options in the Physics dock widget
  • Interface Tracking, Number of Fluids and Flow ModeBackground information on interface tracking methods and defining the number of fluids. Description of the Volume of Fluid (VOF) method for simulation of complex free surfaces, and how this affects the selection of the number of fluids. Examples are presented for one fluid and two fluid simulations.
  • Activating Physics ModelsDemonstration for how to activate physics models and how to limit the display of inactive physics models using the physics model filter.
Physics Models PART 4 OF THE FLOW-3D V12.0 TRAINING SERIES
Fluid Properties PART 5 OF THE FLOW-3D V12.0 TRAINING SERIES

유체 속성

  • Fluids Dock Widget OverviewIntroduction to the Fluids dock widget and how to define properties for fluids in the simulation.
  • Defining Fluid Properties ManuallyExample for how to manually define fluid properties.
  • Defining Fluid Properties from the Materials DatabaseExample for how to load fluid properties from the fluids database.
  • Managing the Materials Database
    How to add and edit entries in the materials database.

지오메트리

  • Introduction
  • Component and Subcomponent Overview
  • Creating Subcomponents: Overview
  • Creating Subcomponents: STL
  • Creating Subcomponents: Primitives Manually
  • Creating Subcomponents: Primitives Interactively
  • Creating Subcomponents: Raster
  • Subcomponent Types
  • Subcomponent Order
  • Component Order
  • Component and Subcomponent Properties
  • Transformations
Geometry PART 6 OF THE FLOW-3D V12.0 TRAINING SERIES
Meshing PART 7 OF THE FLOW-3D V12.0 TRAINING SERIES

Meshing

  • Meshing Introduction
  • Coordinate Systems
  • FAVOR™
  • Meshing Basics: Meshing Overview
  • Meshing Basics: Creating Mesh Blocks
  • Meshing Basics: Domain Extents
  • Meshing Basics: Global Controls
  • Meshing Basics: Local Controls
  • Reviewing Mesh Quality: FAVORize
  • Reviewing Mesh Quality: Preprocessing
  • Multi-block Meshing
  • Conforming Mesh Blocks
  • Meshing Best Practices

Boundary Conditions

  • Introduction
    Introductory comments regarding how boundary conditions are applied and other considerations when defining BCs.
  • Boundaries Dock Widget Overview
  • Velocity
  • Volume Flow Rate
  • Wall
  • Symmetry
  • Grid Overlay
  • Pressure
  • Continuative
  • Outflow
    Description and example setup of the Outflow BC type.
Boundary Conditions PART 8 OF THE FLOW-3D V12.0 TRAINING SERIES
Initial Conditions PART 9 OF THE FLOW-3D V12.0 TRAINING SERIES

Initial Conditions

  • Introduction
    Discussion of how the initial conditions and can affect simulation results and run times.
  • Options for Defining ICs
    Example: Global Settings
    Example: Fluid Regions
  • Example: Function Coefficients
    Description and example for defining spatially varying fluid properties with user defined functions.
  • Example: Pointers
    Description and example for defining an initial condition by filling contiguous cells with the Pointer object.

Output Options

  • Output Dock Widget Overview
  • Spatial Data
  • Spatial Data: Restart Data
  • Spatial Data: Selected Data
  • History Data
  • Diagnostics: Short Print Data
  • Diagnostics: Long Print Data
  • Example Setup
  • Batch Post-processing
  • Batch Mode: Context File
  • Batch Mode: Manual
  • Batch Mode: Generate Reports
Output Options PART 10 OF THE FLOW-3D V12.0 TRAINING SERIES
Baffles PART 11 OF THE FLOW-3D V12.0 TRAINING SERIES

Baffles

Introduction
An introduction to the available options for creating and defining baffle objects.
Creating Baffle Objects
Limitations
Force Outputs
Porosity
Scalar Reset Options
Summary
A summary of the important options for creating baffles and defining properties.

Measurement Devices

  • History Probes 
    History probes are point measurement devices and are used to record solver output at a specific location. Examples are provided for how to create these objects interactively and by defining a coordinate value.
  • Flux Surfaces 
    Flux surfaces are a special type of baffle object with a fixed porosity of 1, and are used to calculate flux quantities. Examples are provided for how to create flux surfaces and the types of data available from their output.
  • Sampling volumes 
    Sampling volumes are are three-dimensional data collection regions. Examples are provided for how to create sampling volumes and the types of data available from their output.
Measurement Devices PART 12 OF THE FLOW-3D V12.0 TRAINING SERIES
W&E Exercise: Ogee Weir

W&E Exercise: Ogee Weir

  • This exercise demonstrates the steps to setup a basic free surface or open channel flow simulation in FLOW-3D. It is intended to be a simple and fast running simulation that demonstrates the key setup steps that can be applied to a wide range of other common open channel flow applications. In this exercise, we will simulate flow over an ogee weir to predict the discharge capacity. Simulation results can be validated against discharge rating curves obtained from physical model measurements (USBR, 1996).  Special attention is given to the common types of boundary conditions used in open channel flow simulations and how to select them during the model setup. We also provide examples for common post-processing tasks using both FLOW-3D and FlowSight.
수자원/수처리/환경분야

수자원 분야

Water & Environmental

FLOW-3D는 작은 하수 처리 시스템부터 대형 수력 발전 프로젝트까지 수처리 및 환경 산업에 직면한 광범위한 문제를 해결할 수 있는 뛰어난 CFD 소프트웨어 입니다. FLOW-3D는 시뮬레이션의 복잡성을 감소시키고 최적의 솔루션에 대해 노력을 집중할 수 있도록 해줍니다. 이를 통해 통해 파악된 가치 있는 통찰력은 귀하의 상당한 시간과 비용을 절약 할 수 있습니다.

실제 지형을 적용하여 3차원 shallow water hybrid model을 이용한 댐 붕괴 시뮬레이션

FLOW-3D는 자유표면 흐름이 있는 수치해석 알고리듬에 의해 유동의 표면이 시공간적으로 변하는 모사를 위한 이상적인 도구라고 할 수 있습니다. 자유 표면은 물과 공기 같은 높은 비율의 밀도 변화를 가지는 유체들 사이의 특정한 경계를 일컫습니다. 자유 표면 흐름을 모델링하는 것은 일반적인 유동방정식과 난류 모델이 결합된 고급 알고리즘을 필요로 합니다. 이 기능은 FLOW-3D로 하여금 침수 구조에 의해 형성된 방수, 수력 점프 및 수면 변화의 흐름의 궤적을 포착 할 수 있습니다.


Bibliography & Technical Data

Figure (17): Stream Lines Indicating Average Flow Speed in the Model with Various Nose shapes, Measured at Mid-Depth and at the Flow Surface Level, at a Flow Rate of 78 Liters per Second.

Conducting experimental and numerical studies to analyze theimpact of the base nose shape on flow hydraulics in PKW weirusing FLOW-3D

FLOW-3D를 사용하여 PKW 둑의 흐름 수력학에 대한 베이스 노즈 모양의 영향을 분석하기 위한 실험 및 수치 연구 수행 Behshad Mardasi ...
그림 12: 시간 경과에 따른 속도 카운터: 30초 그림 13: 시간 경과에 따른 속도 카운터: 20초

Gemelo digital del puente de Kalix: cargas estructurales de futuros eventos climáticos extremos

Kalix Bridge 디지털 트윈: 미래 극한 기후 현상으로 인한 구조적 부하 Este documento está relacionado con un proyecto en curso ...

Discharge Coefficient of a Two-Rectangle Compound Weir combined with a Semicircular Gate beneath it under Various Hydraulic and Geometric Conditions

다양한 수력학적 및 기하학적 조건에서 아래에 반원형 게이트가 결합된 두 개의 직사각형 복합 웨어의 배수 계수 ABSTRACT Two-component composite hydraulic ...
The impacts of profile concavity on turbidite deposits: Insights from the submarine canyons on global continental margins

The impacts of profile concavity on turbidite deposits: Insights from the submarine canyons on global continental margins

프로필 오목부가 탁도 퇴적물에 미치는 영향: 전 세계 대륙 경계에 대한 해저 협곡의 통찰력 Kaiqi Yu a, Elda Miramontes bc, Matthieu J.B. Cartigny d, Yuping Yang a, Jingping Xu aaDepartment of Ocean Science and ...
Fig. 3. Free surface and substrate profiles in all Sp and Ls cases at t = 1 s, t = 3 s, and t = 5 s, arranged left to right (note: the colour contours correspond to the horizontal component of the flow velocity (u), expressed in m/s).

Numerical investigation of dam break flow over erodible beds with diverse substrate level variations

다양한 기질 수준 변화를 갖는 침식성 층 위의 댐 파손 흐름에 대한 수치 조사 Alireza Khoshkonesh1, Blaise Nsom2, Saeid Okhravi3*, ...
그림 10. 수문이 고르지 않게 열리는 경우의 시뮬레이션 결과

홍수 시즌에 하수구를 운영할 때 흐름 회로를 제어하는 ​​기술, 푸토코무네 제방을 통해 제방에 적용

요약 대규모 홍수 구호 작업에 대한 일반적인 흐름 회로 현상의 영향은 많은 보고서에서 연구되었으며 비교적 자세하게 연구되었습니다. 그러나 유량 변동이 ...
Figure 3. Computed contour of velocity magnitude (m/s) for Run 1 to Run 15.

FLOW-3D 소프트웨어를 이용한 유입구 및 배플 위치가 침전조 제거 효율에 미치는 영향

Ali Poorkarimi1 Khaled Mafakheri2Shahrzad Maleki2 Journal of Hydraulic StructuresJ. Hydraul. Struct., 2023; 9(4): 76-87DOI: 10.22055/jhs.2024.44817.1265 Abstract 중력에 의한 침전은 부유 ...
Figure 1 | Schematic of the present research model with dimensions and macro-roughnesses installed.

On the hydraulic performance of the inclined drops: the effect of downstreammacro-roughness elements

경사 낙하의 수력학적 성능: 하류 거시 거칠기 요소의 영향 Farhoud Kalateh a,*, Ehsan Aminvash a and Rasoul Daneshfaraz ba Faculty ...
Effects of ramp slope and discharge on hydraulic performance of submerged hump weirs

Effects of ramp slope and discharge on hydraulic performance of submerged hump weirs

Arash Ahmadi a, Amir H. Azimi b Abstract 험프 웨어는 수위 제어 및 배출 측정을 위한 기존의 수력 구조물 중 하나입니다. 상류 및 하류 경사로의 ...
그림 0 - 임계값의 다양한 위치에서 슬라이딩 밸브를 통과하는 흐름의 개략도: a) 밸브 아래, b) 밸브의 하류 측에 접선, c) 밸브의 상류 측에 접선

수직 슬라이딩 밸브의 토출 계수에 대한 형상 및 임계 위치 변화의 영향 평가

Abstract 본 연구의 목적은 다양한 위치에서 임계값을 갖는 슬라이딩 밸브의 유량계수를 조사하는 것입니다. 이 목표를 달성하기 위해 슬라이딩 밸브 아래 ...


FLOW-3D Water & Environmental Brochure (FSI) Bibliography

Models

  • Air Entrainment
  • Hybrid Shallow Water/3D Flow
  • Sediment Scour
  • Turbulence
  • More Modeling Capabilities

Case Studies

  • Evaluating Hydraulic Energy Losses and Total Hydraulic Head with FLOW-3D‘s Flux Baffles
  • Modeling Commercial Aquaculture Systems
  • Modeling Local Bridge Scour during Flood Event

Conference Proceedings

연료 탱크 슬로싱

시뮬레이션 사례 설명

이 예는 제트 전투기 연료 탱크 내 연료 슬로싱을 나타냅니다. 이 시뮬레이션을 통해 엔지니어는 탱크 내 연료 모션을 제어하는 배플의 성능을 평가하고 적절한 제어 시스템을 설계할 수 있습니다.

자세한 내용이 궁금하시면 언제든지 기술지원팀에 연락주시기 바랍니다.

This example represents fuel sloshing in a jet fighter fuel tank. The simulation allows engineers to evaluate the performance of the baffles in controlling the fuel motion in the tank and to design appropriate control systems.

Fuel Tank Sloshing

FLOW-3D HYDRO Conveyance Infrastructure

FLOW-3D & computational fluid dynamics for civil engineering

Conveyance systems

  • Tunnels
  • Overflows
  • Hydraulic controls
    • Gates
    • Weirs
    • Orifice
  • Drop structures
  • Flow splitting
  • Open channel conveyance
  • Pumps
  • Flap gates (moving objects)
  • Air flow / air supply
  • Entrained air (entrainment, evolution, drift flux, buoyancy, bulking, de-aeration)

Baffle dropshaft

Tangential dropshaft

Sample GUI packaged conveyance examples

Conveyance systems: simulation outputs

해석 결과로 얻을 수 있는 Simulation outputs

  • Pressure, velocity field
  • Water elevation profiles
  • 3D transient behaviors
  • Surges & sloshing
  • Pump approach flow
  • Pump discharge & operations
  • Air phase
  • Entrained air
  • Forces & coupled motion for moving objects

FLOW-3D HYDRO- Dams & Spillways

Dams & spillways Long history of success

  • Government regulators
  • Hydro-power utilities
  • Engineering consultants
  • Hydraulics laboratories
  • CFD consultants
  • Academia

Dams & spillways

•Wide range of applications

•Wide range of flow conditions:
–Open channel
–Pressurized –Mixed

•Wide range of models
FLOW-3D HYDRO is a solution that is:

  • Versatile
  • Robust
  • Accurate

Spillway rating curve
Draft tube exit hydraulics
Flow distribution at turbine entrance
Head loss & energy dissipation
Forces on dams
Aerated flows
Spillway approach conditions
Jet deflection on upper spillway
Spillway water profile
Fish passage hydraulics
Forces on Spillways
Sediment & Scour

Limitless dam, spillway & stilling basin configurations

–Weirs & hydraulic controls
–Ogee
–Gated
–Staircase
–Siphon
–Bucket
–Morning glory
–Labyrinth
–Piano Key weir
–Arced weirs
–…

FLOW-3D HYDRO에는 수십 가지 예가 사전 탑재되어 있어 응용 프로그램 모델링을 시작할 수 있는 좋은 출발점을 제공합니다.

Ray-tracing an upcoming post-processing feature

Fishways

기하학적 또는 흐름 구성에 대한 제한 없음: FLOW-3D HYDO는 속도, 공기 흡입 및 난류장과 같은 중요한 흐름 특성을 매우 정확하게 표현합니다.

  • Natural fishways
  • Pool & weir
  • Pool & orifice
  • Larinier
  • Ice-harbor
  • Natural
  • Baffle
  • Vertical slot
  • Denil •…
  • Simulation outputs
  • Detail of velocity field
  • Water elevation profiles

Spatial mapping of turbulence intensity

Determination of flow conditions:
–Skimming
–Plunging
–Intermittent

지속 가능한 건축물 LEED 인증 획득한 건축사례

USGBC LEED4.1

LEED (Leadership in Energy and Environmental Design)는 제 3자가 친환경 건축물 인증을 제공하는 자발적 인증 시스템입니다. LEED 자발적 참여는 리더십, 혁신, 환경 보호 및 사회적 책임을 보여 줍니다. LEED는 건물 소유자와 운영자에게 건물의 성능과 수익에 즉시 영향을 미치는데 필요한 도구를 제공하는 동시에 건물 거주자에게 건강한 실내 공간을 제공합니다.

FLOW-3D는 보고타(콜롬비아)의 사무실 건물에서 “IEQ-Credit2–환기 증가”라는 신뢰를 얻는 데 큰 도움을 주었습니다. 이러한 인정을 받기 위해서는 실외 공기가 ASHRAE의 표준 비율인 30%를 초과한다는 것을 증명해야만 합니다. 이 건물에서 실외 공기는 태양 광선에 의해, 가열되는 지붕 위의 2개의 유리 굴뚝에 의해 발생되는 온도 차이에 의해 발생하는 열 부력의 영향으로 제공됩니다. 이것은 바람이 불지 않는 조건에서 이루어져야 합니다.

The model has been easily created using Google SketchUp® and exported directly to FLOW-3D in STL format. The STL model was imported as STL baffles in FLOW-3D.

외부 에너지 시뮬레이션 소프트웨어를 통해 공간 및 열 하중(또는 손실)의 초기 조건을 파악했습니다. 이 소프트웨어는 태양열 복사, 열 관성, 단열, 내부 부하, 단열, 유리 및 건물의 열 동작을 정의하는 기타 모든 매개 변수를 고려합니다. 열 하중은 FLOW-3D에 포함되어 있어 CFD시뮬레이션이 수행될 때 최종 온도 분포를 제공합니다.

<좌측>건물 내부의 공기 흐름이 간소화됩니다.     <우측>건물 내부 온도 분포

왼쪽 그림에서 2개의 열 굴뚝은 바람이 전혀 없는 상태에서도 실외 공기 유입을 유발합니다. 환기 효율, 시간당 공기 변화, 국소 난류, 공기 잔류 시간은 설계 프로세스에서 검사할 수 있는 변수 중 일부입니다. 오른쪽 그림에서 FLOW-3D는 건물 내부의 온도 분포를 제공하여 설계 과정에서 열적 쾌적성 평가를 수행할 수 있도록 합니다. 그릴 크기는 모든 공간에서 원하는 쾌적한 온도를 얻을 수 있도록 조정할 수 있습니다.

외부 공기 온도와 기압은 경계 조건(흡입 및 배출 공기 그릴)에서 설정되었습니다. 나머지는 건물 내부에서 상세한 공기 이동을 분석한 것입니다. 시뮬레이션은 에너지가 정상 상태 조건이 달성될 때까지 수행되었다.

건물 내 공기를 올바르게 분배하고 적절한 쾌적한 온도를 확보하기 위해 건물 구조와 그릴 치수를 조정해야 했습니다. 이 과정을 반복한 후 모델을 검증하여 LEED 인증 조건을 충족한 사례입니다.

밀도류 배플 시스템

Density Current Baffle Systems

Thanks to Mr. Earle Schaller and Dr. John Richardson for contributing this material.

NEFCO엔지니어들이 Density Current Baffle 시스템을 설계하는데 사용되는 절차를 개선하고자 했을 때, 그들은 경험에 기초한 종합적인 최첨단 모델링과 컴퓨터 모델링 분석 접근법을 개발했습니다.

Background                   

순환된 활성 슬러지 2 차 침전조는 중력에 의존하여 고형물을 정화하고 맑은 물을 생성합니다. 그러나, 원형 분류기는 탱크 내에서 발생된 밀도류에 의해 단락 회로에 영향을 받습니다. 침전조 내부에 설치된 밀도류 배플은 단락 회로의 영향을 최소화하고 유출 품질을 개선하는 가장 효과적인 방법으로 밝혀졌습니다. Stamford Density Current Baffle은 오늘날 사용되는 가장 일반적인 유형입니다. NEFCO는 물과 폐수처리 산업을 위한 공학적 섬유 유리제품을 생산합니다. 이 회사는 Stamford Baffle의 디자인과 개발을 선도했으며 이러한 배플 시스템의 세계적인 공급 업체입니다.

NEFCO Density Current Baffle Systems

NEFCO의 배플 디자인 접근 방식은 지난 20년간 개발되고 개선된 크기 알고리즘과 함께 광범위한 현장 연구가 결합되면서 시작됩니다. 이러한 노력 덕분에 회사는 다양한 표준 및 비표준 식별자 구성에 대한 배플을 설계할 수 있었습니다. 가장 최근에는 NEFCO가 FLOW-3D의 연산 모델링 능력을 사용하여 배플에 대한 이해를 더욱 넓히고 새로운 설계 전략을 개발했습니다.

환경 보호국 (Environmental Protection Agency, EPA)의 연구에 따르면 크기나 모양에 상관없이 모든 활성 슬러지의 2차 침전지에 밀도류가 형성되며 침전지 성능에 심각한 악영향을 미친다는 것을 보여줍니다. 이러한 밀도류는 흔히 탱크의 바닥으로 흘러 들어가 상대적으로 높은 속도의 문제를 일으킬 때 발생합니다. 이러한 교란 또는 밀도류는 슬러지 덮개 바로 위의 수평면으로 이동하여 더 가벼운 고체를 이용하여 탱크의 주요 부피를 줄입니다. 밀도류는 이러한 가벼운 고체를 유출로 운반하는 탱크 벽 위로 이동합니다. 그 결과 총 부유 물질(TSS)이 크게 증가하고 보존 시간이 크게 감소합니다.

Calculated flow pattern at outer wall of circular clarifier. Color range chosen to show location of sludge blanket.

 

A Picture is Worth a Thousand Words

Circular clarifier, cut-away view (not to scale)         

 

NEFCO는 Blue Hill Hydraulics와 협력으로 FLOW-3D로 Stamford Density Current Baffle System의 성능을 연구하기 위해 70 피트 3 차원 원형모델을 개발했습니다.

정화기 내의 유동 패턴 및 고체 분포는 배플 길이, 경사각 및 수직 위치를 포함하는 다양한 밀도류 배플 파라미터에 기초하여 계산되었습니다.

Solutions that Work

NEFCO사의 tamford Density Current Baffle System은 명확하게 구분할 수 있도록 탱크 내의 밀도류 흐름을 차단하고 방향을 바꾸도록 특별히 설계되었습니다. 이 시스템은 유압 용량을 증가시키고 총 부유 물질을 50%까지 감소시킵니다. FLOW-3D분석 결과,  NEFCO의 배플 설계 알고리즘을 확인하고 NEFCO가 최신 배플 설계 전략에 통합하고 있는 Baffle 성능에 대한 고유한 통찰력을 제공합니다.

Predicted flow patterns without the Stamford Density Current Baffle (colored by speed, red is fast)

Predicted flow patterns with the Stamford Density Current Baffle (colored by speed, red is fast)

Improving Clarifier Performance

Improving Clarifier Performance

 

Thanks to Mr. Earle Schaller and Dr. John Richardson for contributing this material.

 

NEFCO엔지니어들이 Density Current Baffle 시스템을 설계하는데 사용되는 절차를 개선하고자 했을 때, 그들은 경험에 기초한 종합적인 최첨단 모델링과 컴퓨터 모델링 분석 접근법을 개발했습니다.

 

Background                   

순환된 활성 슬러지 2 차 침전조는 중력에 의존하여 고형물을 정화하고 맑은 물을 생성합니다. 그러나, 원형 분류기는 탱크 내에서 발생된 밀도 전류에 의해 단락 회로에 영향을 받습니다. 침전조 내부에 설치된 밀도 전류배플은 단락 회로의 영향을 최소화하고 유출 품질을 개선하는 가장 효과적인 방법으로 밝혀졌습니다. Stamford Density Current Baffle은 오늘날 사용되는 가장 일반적인 유형입니다. NEFCO, Incorporated는 물과 폐수처리 산업을 위한 공학적 섬유 유리제품을 생산합니다. 이 회사는 Stamford Baffle의 디자인과 개발을 선도했으며 이러한 배플 시스템의 세계적인 공급 업체입니다.

NEFCO Density Current Baffle Systems

NEFCO의 배플 디자인 접근 방식은 지난 20년간 개발되고 개선된 크기 알고리즘과 함께 광범위한 현장 연구가 결합되면서 시작됩니다. 이러한 노력 덕분에 회사는 다양한 표준 및 비표준 식별자 구성에 대한 배플을 설계할 수 있었습니다. 가장 최근에는 NEFCO가 FLOW-3D의 연산 모델링 능력을 사용하여 배플에 대한 이해를 더욱 넓히고 새로운 설계 전략을 개발했습니다.

환경 보호국 (Environmental Protection Agency, EPA)의 연구에 따르면 크기나 모양에 상관없이 모든 활성 슬러지의 2차 침전지에 밀도 전류가 형성되며 침전지 성능에 심각한 악영향을 미친다는 것을 보여줍니다. 이러한 전류는 흔히 탱크의 바닥으로 흘러 들어가 상대적으로 높은 속도의 장애를 일으킬 때 발생합니다. 이러한 교란 또는 밀도 전류는 슬러지 덮개 바로 위의 수평면으로 이동하여 더 가벼운 고체를 이용하여 탱크의 주요 부피를 줄입니다. 밀도 전류는 이러한 가벼운 고체를 유출로 운반하는 탱크 벽 위로 이동합니다. 그 결과 총 부유 물질(TSS)이 크게 증가하고 보존 시간이 크게 감소합니다.

Calculated flow pattern at outer wall of circular clarifier. Color range chosen to show location of sludge blanket.

 

A Picture is Worth a Thousand Words

Circular clarifier, cut-away view (not to scale)         

 

NEFCO는 Blue Hill Hydraulics와 협력으로 FLOW-3D로 Stamford Density Current Baffle System의 성능을 연구하기 위해 70 피트 3 차원 원형모델을 개발했습니다.

정화기 내의 유동 패턴 및 고체 분포는 배플 길이, 경사각 및 수직 위치를 포함하는 다양한 밀도 전류 배플 파라미터에 기초하여 계산되었다.

Solutions that Work

NEFCO스탬포드 밀도 전류 Baffle 시스템은 명확하게 구분할 수 있도록 탱크 내의 밀도 전류 흐름을 차단하고 방향을 바꾸도록 특별히 설계되었습니다. 이 엔지니어링 된 시스템은 유압 용량을 증가시키고 총 부유 물질을 50%까지 감소시킵니다. FLOW-3D분석은 NEFCO의 배플 설계 알고리즘을 확인하고 NEFCO가 최신 배플 설계 전략에 통합하고 있는 Baffle 성능에 대한 고유한 통찰력을 제공합니다.

Predicted flow patterns without the Stamford Density Current Baffle (colored by speed, red is fast)

Predicted flow patterns with the Stamford Density Current Baffle (colored by speed, red is fast)

FLOW-3D의 활용 및 설계 적용 사례 (5)

항공우주 분야의 활용

FLOW-3D를 활용한 항공우주 분야의 주요한 사례는 슬로싱(sloshing)에 의한 유체의 유동 영향을 평가하는 해석과 기상(gas phase) 유체에 대한 아음속 및 초음속 유동 해석으로 크게 나눌 수 있다.

슬로싱 유동 해석
슬로싱(sloshing)은 탱크 내부에 적재된 유체가 외부의 가진에 의하여 발생하는 유동 현상이다. 이는 흔히 볼 수 있는 컵 내부 물의 유동부터 항공기 및 선박, 우주선의 연료탱크 내부 유동까지 다양한 분야에서 나타나는 유동 현상이다. 이러한 슬로싱의 영향은 유체와 탱크의 상호 작용으로 충격 압력이 발생하게 되며, 슬로싱에 의한 충격이 계속 반복되면서 탱크 내부에 피로로 인한 균열(crack)로 탱크의 파괴를 초래할 수 있다.
그 동안 슬로싱 현상을 연구하기 위해 많은 실험과 수치 해석이 수행되어 왔다. 우주 로켓의 연료 탱크와 관련된 슬로싱 유동에 대하여 많은 연구들이 진행된 바 있고, 1980년대 이후에는 LNG 수송선이 증가하면서 선박 내의 슬로싱 유동에 대한 많은 연구가 진행되었다. 실험적인 연구 방법은 많은 실험비용과 시간 및 장비가 요구되기 때문에 이를 대치하기 위하여 많은 수치해석이 시도되어 왔다. 
Faltinsen은 진동하는 2차원 슬로싱 문제에 대하여 수치해석을 하였고, Wu et al은 유한 요소 법을 이용하여 3차원 수치해석을 시도하였다. 자유표면 문제에 대해서 수치적 확산을 줄이기 위하여 Takewaki and Yabe에 의하여 CIP(constrained interpolation profile) 기법이 개발 되었고, Yang and Kim은 2009년 물과 공기의 다상 문제를 해석하는 CCUP(Cip-combined and unified procedure) 기법을 이용하여 슬로싱 문제에 대한 수치해석을 수행하였다. 3차원 열유동 해석 프로그램인 FLOW-3D를 이용한 해석은 2006년 Lee et el.에 의하여 수행된 바 있다. 
현재까지 슬로싱 현상을 해석하기 위하여 많은 수치기법들이 개발되고 이용되어 왔지만, 슬로싱의 특성상 강한 비선형 자유표면에 대한 정확한 해석에 어려움이 남아있다. 이러한 비선형 슬로싱 문제에 대하여 FLOW-3D를 이용하여 수치해석하였고, 앞서 진행되었던 실험 및 수치해석 연구 결과의 압력 및 자유표면의 형상을 비교하였다.
해석결과와 실험을 비교하기 위하여 해석을 진행하였으며, 탱크의 형상을 <그림 1>에 나타냈다. 이 모델에 대한 실험은 1991년 히타치(Hitachi) 조선 연구소와 대우조선해양에서 수행한 바 있다.


그림 1. 스키매틱 다이어그램(schematic diagram) without baffles, fluid filling 50%

초기에 탱크는 정지상태로부터, 다음 식과 같이 좌우로 병진운동을 하게 된다.

다운로드 : [ 5회_201805_analysis_flow3d ]

작성자 | 민창원_에스티아이C&D 솔루션 사업부 과장,  조애령_에스티아이C&D 솔루션 사업부 차장
이메일 | flow3d@stikorea.co.kr
홈페이지 | www.flow3d.co.kr

출처 : CAD&Graphics 2018년 05월호

FLOW-3D CAST 사양

FLOW-3D CAST Feature


Active Simulation Control

실행중인 해석의 제어 파라미터는 History probes에서 사용자가 정의한 조건에 따라, 런타임 동안에 자동으로 변경 될 수 있습니다. History probes에 의해 기록된 시뮬레이션 변수는 경계 조건, mass source 및 General Moving Object 기능을 이용하여, 시간에 따른 개체의 동작을 제어하기 위해 사용될 수있습니다. 예를 들어, 고압다이캐스팅 해석에서 게이트에 설정한 History probes에 유체가 도달하면, 그 정보를 캡처하는 데이터 출력 주파수를 증가시켜 플런저의 속도를 고속으로 자동 전환 될 수있습니다. 고압다이캐스팅 해석은 유체가 게이트에 도달 할 때 자동으로 고속 전환됩니다. 이 프로세스는 새로운 실행 시뮬레이션 제어 기능을 통해 자동으로 진행됩니다. 저속 구간에서 플런저의 움직임은 trigger 슬리브의 용융물에 혼입되는 공기의 양을 최소화하기 위해 Barkhudarov 방법 1을 사용하여 계산됩니다. 이 결과는 훨씬 더 높은 품질의 주조품이 나올수 있도록 설계하는데 도움이 될 수 있습니다. Read the development note > Read the blog post >

Batch Postprocessing & Report Generation

Batch 후처리 및 보고서 생성은 해석 결과 분석시 사용자의 해석 처리 시간을 절약하기 위해 개발되었습니다. Batch 후처리는, 해석이 완료된 후, 사용자가 애니메이션, 시나리오, 그래프, 텍스트 데이터 시리즈를 정의하여 자동으로 생성되도록 할 수 있습니다. 그래픽 요청은 백그라운드에서 FlowSight를 실행하여 처리되도록 FLOW-3D Cast에 정의되어 있습니다. 원하는 해석 결과를 생성할 수 있는 컨텍스트 파일을 사용하면 Batch 후처리 기능을 사용할 수 있습니다. Batch 후처리가 완료되면, 사용자는 쉽게 자신의 관리자, 동료, 또는 클라이언트에 보낼 수있는 HTML5 형식의 완벽한 기능을 갖춘 보고서를 만들 수 있습니다. 이미지 및 동영상도 보고서에 포함 할 수 있고, 사용자는 텍스트, 캡션, 참고 문헌의 형식을 완벽하게 제어 하고 유지할 수 있습니다. Read the blog post >

Metal Casting Models

Squeeze Pin Model

스퀴즈 핀은 주조시 주입 공급이 어려운 영역에서, 응고하는 동안 금속 수축을 보상하기 위해 사용되는 실제의 다이 캐스팅 머신의 동작을 모델링하는 해석을 할 수 있습니다. 스퀴즈 핀은 선택된 표면에 cylinderical squeeze pin을 추가하여, STL 파일 또는 대화식으로 생성 될 수 있습니다. Read the development note >

Intensification Pressure Model

새로운 플런저 타입 형상이 추가 되었습니다. 강화된 압력 조건으로 macro-shrinkage 와 micro-porosity 제거를 지정할 수 있습니다.

Thermal Die Cycling model

FLOW-3D Cast v4.1's full process thermal die cycling model

다이싸이클링 (Thermal die cycling, TDC) 모델에 새로운 두 가지의 단계가 추가되었습니다. 금형이 열린 상태에서 제품이 여전히 금형 내부에 있는 ejection 단계와, 금형이 닫혔지만 사출 바로전의 preparation 단계가 추가되었습니다. 또한, 마지막 싸이클만이 아닌 모든 금형 싸이클 모두 수렴된 결과를 전달하기 위해 TDC 솔버가 성능 손실 없이 최적화 되었습니다. Read the blog post >

Valves and Vents

Modeling valves and vents in FLOW-3D Cast v4.1

밸브와 밴트의 외부 압력과 온도는 이제 사용자가 다이 캐스팅 공정에서 충진중에 보다 실제적인 동작을 정의 할 수 있도록, 시간의 표 함수로서 정의 할 수있습니다. 밸브 및 벤트의 압력 및 온도는 프로세스 설계 단계에서 유용한 제품 내부에 설정된 프로브에 의해 제어 될 수 있습니다.

PQ2 Diagram

PQ2다이어그램의 사용은 사용자가 더 나은 슬리브의 플런저 실제 움직임과 유사하게 적용 할 수 있습니다. 새로운 기능은 실제 공정 변수가 아직 알려져 있지 않았을 때 다이캐스팅 설계 단계 중에 특히 유용합니다. Read the blog post >

Cooling Channels

냉각 채널은 금형 각각의 냉각 유로에 의해 제거되거나 추가된 열의 총량에 의해 제어 될 수 있습니다. Read the development note >

Air Entrainment Model

Air entrainment 모델에 compressibility를 입력하는 새로운 옵션이 추가되었습니다. 고압 다이캐스팅의 충진 공정과 같은 경우, 공기 압축성은 유체 압력의 변화로 인한 유체의 흐름에 중요한 인자가 됩니다.
 

Cavitation Model

캐비테이션 모델은 유동 조건의 더 넓은 범위에 걸쳐 유체의 캐비테이션 거동을 나타내도록 개선되었습니다. 캐비테이션 생성에 대한 새로운 옵션은 경험적 관계를 기반으로, 기존의 일정한 속도로 생성되는 방식에서 보완되었습니다. 새로운 passive gas model 옵션은 open bubbles이 아닌 유체내에 cavitationg gas를 추적하여, 계산에 필요한 격자와 계산시간을 줄일 수 있습니다. Read the development note >

Two-fluid Phase Change Model

Two-fluid phase change model 은 과냉각을 포함하도록 확장되었습니다. 일정한 과냉각 온도를 정의하고 가스 온도가 응축이 일어나기 전에 포화점 이하로 내려갈 수 있게 함으로써 구현됩니다.

Simulation Results and Analysis

Simulation Results File Editor

사용자가 FLOW-3D Cast v4.1 결과 파일들을 병합 및 제거 할 수 있는 편집 유틸리티

Linking flsgrf.* files

Restart 해석 결과 파일들(flsgrf.*)은 FlowSight 에서 하나의 연속적인 애니메이션 결과를 표시하기 위해 restart source 결과로 링크될 수 있습니다.

Fluid/wall Contact Time

A new spatial quantity has been added to the solution output that stores the time that metal spent in contact with each geometric component, as well as the time spent by each component with metal.

용탕이 각 geometry 컴포넌트를 접촉한 시간과 각 컴포넌트가 용탕과의 접촉 시간을 나타내는 새로운 공간적 양이 해석 아웃풋에 추가 되었습니다.

Performance and Usability

Calculators

열전달 계수, 열 침투 깊이, 밸브 손실 계수, 슬리브에 용탕량(깊이), 플런저의 속도를 계산할 수 있는 Calculators 기능이 Model Setup 창에서 바로 가능해졌습니다. 또한 유틸리티 메뉴에서도 가능합니다.

Thermal Die Cycling

Heat transfer database in FLOW-3D Cast v4.1

열전달 계수 데이터베이스와 각 싸이클 단계들이 입력되어있어 간편하게 다이싸이클링 해석을 하실 수 있습니다.

GMRES Pressure Solver

GMRES pressure solver의 속도가 솔버 데이터 구조의 최적화로 인해 2배까지 향상되었습니다. 이로 인해 메모리 사용량이 20% 미만으로 증가할 수 있습니다. Read the blog post >

Sampling Volumes

Sampling volume 기능은 STL로 정의할 수 있습니다. 각 sampling volume에 의해 계산된 양들의 목록은 유체의 부피, 최대/최소 온도, 파티클의 갯수와 같은 전체 해석 영역에 대해 모두 같은 양이 되도록 확장되었습니다.

 

FSI/TSE Model

구조분석 모델의 성능이 부분적인 coupling으로 해석 솔버의 병렬화와 최적화를 통해 향상되었습니다.

Workspaces

Workspaces 를 이전에 설치된 FLOW-3D에서 가져올 수 있습니다. Workspaces 와 사용자가 선택한 시뮬레이션들을 복사할 수 있습니다.

Expanded Simulation Pre-check

Simulation pre-check 기능은 preprocessor checks를 포함하고, 문제가 발생하는 경우 링크됩니다.

Improved Transparency

Depth-peeling 옵션은 transparent geometries 를 좀 더 잘 표현하고, v4.0보다 10배 빨라졌습니다.

Interactive Tools

Baffles, history probes, void/fluid pointers, valves, mass-momentum sources, squeeze pins에 대한 새로운 대화형 생성 기능이 추가되었습니다. 또한 probing과 clipping 도구들이 대화형으로 개선되었습니다.

General Enable/Disable

모든 objects (e.g., mesh blocks)은 활성화/비활성화 할 수 있습니다.

Estimated Remaining Simulation Time

솔버 메세지 파일에 short-print로 추정된 잔여 해석 시간이 추가 되었습니다.

Tabular Data

테이블 형식의 데이터에서 선택된 데이터를 마우스 오른쪽 버튼을 클릭하여 csv파일 또는 외부 파일에 복사, 저장할 수 있습니다.

1 23-10 Michael R. Barkhudarov, Minimizing Air Entrainment, The Canadian Die Caster, June 2010

General Applications Bibliography

다음은 일반 응용 분야의 기술 문서 모음입니다.
이 모든 논문은 FLOW-3D  결과를 포함하고 있습니다. 복잡한 다중 물리와 관련된 문제를 성공적으로 시뮬레이션하기 위해 FLOW-3D를 사용 하는 방법에 대해 자세히 알아보십시오.

Below is a collection of technical papers in our General Applications Bibliography. All of these papers feature FLOW-3D results. Learn more about how FLOW-3D can be used to successfully simulate problems that involve complex multiphysics.

2024년 3월 20일 Upate

204-23   Togo Shinonaga, Hibiki Tajima, Yasuhiro Okamoto, Akira Okada, Application of large-area electron beam irradiation to micro-edge filleting, Journal of Manufacturing Processes, 107; pp. 65-73, 2023. doi.org/10.1016/j.jmapro.2023.10.039

167-23   Xiaoyong Cheng, Zhixian Cao, Ji Li, Alistair Borthwick, A numerical study of the settling of non-spherical particles in quiescent water, Physics of Fluids, 35.9; 2023. doi.org/10.1063/5.0165555

109-23 Dileep Karnam, Yu-Lung Lo, Chia-Hua Yang, Simulation study and parameter optimization of laser TSV using artificial neural networks, Journal of Materials Research and Technology, 25; pp. 3712-3727, 2023. doi.org/10.1016/j.jmrt.2023.06.199

66-23   Erik Holmen Olofsson, Michael Roland, Jon Spangenberg, Ninna Halberg Jokil, Jesper Henri Hattel, A CFD model with free surface tracking: predicting fill level and residence time in a starve-fed single-screw extruder, The International Journal of Advanced Manufacturing Technology, 126; pp. 3579-3591, 2023. doi.org/10.1007/s00170-023-11329-w

20-23   Giampiero Sciortino, Valentina Lombardi, Pietro Prestininzi, Modelling of cantilever-based flow energy harvesters featuring C-shaped vibration inducers: The role of the fluid/beam interaction, Applied Sciences, 13.1; 416, 2023. doi.org/10.3390/app13010416

134-22   Guozheng Ma, Shuying Chen, Haidou Wang, Impact spread behavior of flying droplets and properties of splats, Micro Process and Quality Control of Plasma Spraying, pp. 87-202, 2022. doi.org/10.1007/978-981-19-2742-3_3

111-22   Chia-Lin Chiu, Chia-Ming Fan, Chia-Ren Chu, Numerical analysis of two spheres falling side by side, Physics of Fluids, 34; 072112, 2022. doi.org/10.1063/5.0096534

58-21   Ruizhe Liu, Haidong Zhao, Experimental study and numerical simulation of infiltration of AlSi12 alloys into Si porous preforms with micro-computed tomography inspection characteristics, Journal of the Ceramic Society of Japan, 129.6; pp. 315-322, 2021. doi.org/10.2109/jcersj2.21018

56-20   Nils Steinau, CFD modeling of ascending Strombolian gas slugs through a constricted volcanic conduit considering a non-linear rheology, Thesis, Universität Hamburg, Hamburg, Germany, 2020.

30-20   Bita Bayatsarmadi, Mike Horne, Theo Rodopoulos and Dayalan Gunasegaram, Intensifying diffusion-limited reactions by using static mixer electrodes in a novel electrochemical flow cell, Journal of The Electrochemical Society, 167.6, 2020. doi.org/10.1149/1945-7111/ab7e8f

75-19   Raphaël Comminal, Marcin Piotr Serdeczny, Navid Ranjbar, Mehdi Mehrali, David Bue Pedersen, Henrik Stang, Jon Spangenberg, Modelling of material deposition in big area additive manufacturing and 3D concrete printing, Proceedings, Advancing Precision in Additive Manufacturing, Nantes, France, September 16-18, 2019.

35-19     Sung-Won Ha, Tae-Won Kim, Joo-Hwan Choi, and Young-Jin Park, Study for flow phenomenon in the circulation water pump chamber using the Flow-3D model, Journal of the Korea Academia-Industrial Cooperation Society, Vol. 20, No. 4, pp. 580-589, 2019. doi: 10.5762/KAIS.2019.20.4.580

27-19     Rolands Cepuritis, Elisabeth L. Skare, Evgeny Ramenskiy, Ernst Mørtsell, Sverre Smeplass, Shizhao Li, Stefan Jacobsen, and Jon Spangeberg, Analysing limitations of the FlowCyl as a one-point viscometer test for cement paste, Construction and Building Materials, Vol. 218, pp. 333-340, 2019. doi: 10.1016.j.conbuildmat.2019.05.127

26-19     Shanshan Hu, Lunliang Duan, Qianbing Wan, and Jian Wang, Evaluation of needle movement effect on root canal irrigation using a computational fluid dynamics model, BioMedical Engineering OnLine, Vol. 18, No. 52, 2019. doi: 10.1186/s12938-019-0679-5

83-18   Elisabeth Leite Skare, Stefan Jacobsen, Rolands Cepuritis, Sverre Smeplass and Jon Spangenberg, Decreasing the magnitude of shear rates in the FlowCyl, Proceedings of the 12th fib International PhD Symposium in Civil Engineering, Prague, Czech Republic, August 29-31, 2018.

71-18   Marc Bascompta, Jordi Vives, Lluís Sanmiqeul and José Juan de Felipe, CFD friction factors verification in an underground mine, Proceedings of the 4th World Congress on Mechanical, Chemical, and Material Engineering, August 16 – 18, 2018, Madrid, Spain, Paper No. MMME 105, 2018. doi.org/10.11159/mmme18.105

56-18   J. Spangenberg, A. Uzala, M.W. Nielsen and J.H. Hattel, A robustness analysis of the bonding process of joints in wind turbine blades, International Journal of Adhesion and Adhesives, vol. 85, pp. 281-285, 2018. doi.org/10.1016/j.ijadhadh.2018.06.009

21-18   Zhang Weikang and Gong Hongwei, Numerical Simulation Study on Characteristics of Airtight Water Film with Flow Deflectors, IOP Conference Series: Earth and Environmental Science vol. 153, no. 3, pp. 032025, 2018. doi.org/10.1088/1755-1315/153/3/032025

59-17  Han Eol Park and In Cheol Bang, Design study on mixing performance of rotational vanes in subchannel with fuel rod bundles, Transactions of the Korean Nuclear Society Autumn Meeting, Gyeongju, Korea, October 26-27, 2017.

58-17  Jian Zhou, Claudia Cenedese, Tim Williams and Megan Ball, On the propagation of gravity currents over and through a submerged array of circular cylinders, Journal of Fluid Mechanics, Vol. 831, pp. 394-417, 2017. doi.org/10.1017/jfm.2017.604

24-17   Zhiyuan Ge, Wojciech Nemec, Rob L. Gawthorpe, Atle Rotevatn and Ernst W.M. Hansen, Response of unconfined turbidity current to relay-ramp topography: insights from process-based numerical modelling, doi: 10.1111/bre.12255 This article is protected by copyright. All rights reserved.

06-17   Masoud Hosseinpoor, Kamal H. Khayat, Ammar Yahia, Numerical simulation of self-consolidating concrete flow as a heterogeneous material in L-Box set-up: coupled effect of reinforcing bars and aggregate content on flow characteristics, A. Mater Struct (2017) 50: 163. doi:10.1617/s11527-017-1032-8

94-16   Mehran Seyed Ahmadi, Markus Bussmann and Stavros A. Argyropoulos, Mass transfer correlations for dissolution of cylindrical additions in liquid metals with gas agitation, International Journal of Heat and Mass Transfer, Volume 97, June 2016, Pages 767-778

83-16   Masoud Hosseinpoor, Numerical simulation of fresh SCC flow in wall and beam elements using flow dynamics models, Ph.D. Thesis: University of Sherbrooke, September 2016.

51-16   Aditi Verma, Application of computational transport analysis – Oil spill dynamics, Master Thesis: State University of New York at Buffalo, 2016, 56 pages; 1012775

37-16   Hannah Dietterich, Einat Lev, and Jiangzhi Chen, Benchmarking computational fluid dynamics models for lava flow simulation, Geophysical Research Abstracts, Vol. 18, EGU2016-2202, 2016, EGU General Assembly 2016, © Author(s) 2016. CC Attribution 3.0 License.

 19-16   A.J. Vellinga, M.J.B. Cartigny, E.W.M. Hansen, P.J. Tallinga, M.A. Clare, E.J. Sumner and J.T. Eggenhuisen, Process-based Modelling of Turbidity Currents – From Computational Fluid-dynamics to Depositional Signature, Second Conference on Forward Modelling of Sedimentary Systems, 25 April 2016, DOI: 10.3997/2214-4609.201600374

106-15    Hidetaka Oguma, Koji Tsukimoto, Saneyuki Goya, Yoshifumi Okajima, Kouichi Ishizaka, and Eisaku Ito, Development of Advanced Materials and Manufacturing Technologies for High-efficiency Gas Turbines, Mitsubishi Heavy Industries Technical Review Vol. 52 No. 4, December 2015

93-15   James M. Brethour, Modelling of Cavitation within Highly Transient Flows with the Volume of Fluid Method, 1st Pan-American Congress on Computational Mechanics, April 27-29, 2015

90-15   Troy Shinbrot, Matthew Rutala, Andrea Montessori, Pietro Prestininzi and Sauro Succi, Paradoxical ratcheting in cornstarch, Phys. Fluids 27, 103101 (2015); http://dx.doi.org/10.1063/1.4934709

84-15   Nicolas Roussel, Annika Gram, Massimiliano Cremonesi, Liberato Ferrara, Knut Krenzer, Viktor Mechtcherine, Sergiy Shyshko, Jan Skocec, Jon Spangenberg, Oldrich Svec, Lars Nyholm Thrane and Ksenija Vasilic, Numerical simulations of concrete flow: A benchmark comparison, Cem. Concr. Res. (2015), http://dx.doi.org/10.1016/j.cemconres.2015.09.022

02-15   David Souders, FLOW-3D Version 11 Enhances CFD Simulation, Desktop Engineering, January 2015

125-14   Herbert Obame Mve, Romuald Rullière, Rémi Goulet and Phillippe Haberschill, Numerical Analysis of Heat Transfer of a Flow Confined by Wire Screen in Lithium Bromide Absorption Process, Defect and Diffusion Forum, ISSN: 1662-9507, Vol. 348, pp 40-50, doi:10.4028/www.scientific.net/DDF.348.40, © 2014 Trans Tech Publications, Switzerland

55-14   Agni Arumugam Selvi, Effect of Linear Direction Oscillation on Grain Refinement, Master’s Thesis: The Ohio State University, Graduate Program in Mechanical Engineering, Copyright by Agni Arumugam Selvi, 2014

99-13   R. C. Givler and M. J. Martinez, Computational Model of Miniature Pulsating Heat Pipes, SANDIA REPORT, SAND2012-4750, Unlimited Release, Printed January 2013.

82-13    Shizhao Li, Jon Spangenberg, Jesper Hattel, A CFD Approach for Prediction of Unintended Porosities in Aluminum Syntactic Foam A Preliminary Study, 8th International Conference on Porous Metals and Metallic Foams (METFOAM 2013), Raleigh, NC, June 2013

81-13   S. Li, J. Spangenberg, J. H. Hattel, A CFD Model for Prediction of Unintended Porosities in Metal Matrix Composites A Preliminary Study, 19th International Conference on Composite Materials (ICCM 2013), Montreal, Canada, July 2013

78-13   Haitham A. Hussein, Rozi Abdullah, Sobri, Harun and Mohammed Abdulkhaleq, Numerical Model of Baffle Location Effect on Flow Pattern in Oil and Water Gravity Separator Tanks, World Applied Sciences Journal 26 (10): 1351-1356, 2013, ISSN 1818-4952, DOI: 10.5829/idosi.wasj.2013.26.10.1239, © IDOSI Publications, 2013

74-13  Laetitia Martinie, Jean-Francois Lataste, and Nicolas Roussel, Fiber orientation during casting of UHPFRC: electrical resistivity measurements, image analysis and numerical simulations, Materials and Structures, DOI 10.1617/s11527-013-0205-3, November 2013. Available for purchase online at SpringerLink.

67-13 Stefan Jacobsen, Rolands Cepuritis, Ya Peng, Mette R. Geiker, and Jon Spangenberg, Visualizing and simulating flow conditions in concrete form filling using Pigments, Construction and Building Materials 49 (2013) 328–342, © 2013 Elsevier Ltd. All rights reserved. Available for purchase at ScienceDirect.

60-13 Huey-Jiuan Lin, Fu-Yuan Hsu, Chun-Yu Chiu, Chien-Kuo Liu, Ruey-Yi Lee, Simulation of Glass Molding Process for Planar Type SOFC Sealing Devices, Key Engineering Materials, 573, 131, September 2013. Available for purchase at Scientific.net.

32-13 M A Rashid, I Abustan and M O Hamzah, Numerical simulation of a 3-D flow within a storage area hexagonal modular pavement systems, 4th International Conference on Energy and Environment 2013 (ICEE 2013), IOP Conf. Series: Earth and Environmental Science 16 (2013) 012056 doi:10.1088/1755-1315/16/1/012056. Full paper available at IOP.

105-12 Jon Spangenberg, Numerisk modellering af formfyldning ved støbning i selvkompakterende beton, Ph.D. Thesis: Technical University of Denmark, ID: 0eeede98-fb07-4800-86e2-0a6baeb1e7a3, 2012.

100-12 Nurul Hasan, Validation of CFD models using FLOW-3D for a Submerged Liquid Jet, Ninth International Conference on CFD in the Minerals and Process Industries, CSIRO, Melbourne, Australia, 10-12 December 2012.

87-12  Abustan, Ismail, Hamzah, Meor Othman and Rashid, Mohd Aminur, A 3-Dimensional Numerical Study of a Flow within a Permeable Pavement, OIDA International Journal of Sustainable Development, Vol. 04, No. 02, pp. 37-44, April 2012.

86-12 Abustan, Ismail, Hamzah, Meor Othman and Rashid, Mohd Aminur, Review of Permeable Pavement Systems in Malaysia Conditions, OIDA International Journal of Sustainable Development, Vol. 04, No. 02, pp. 27-36, April 2012.

85-12  Mohd Aminur Rashid, Ismail Abustan, Meor Othman Hamzah, Infiltration Characteristic Modeling Using FLOW-3D within a Modular Pavement, Procedia Engineering, Volume 50, 2012, Pages 658-667, ISSN 1877-7058, 10.1016/j.proeng.2012.10.072.

73-12  Mohd Aminur Rashid, Ismail Abustan, Meor Othman Hamzah, Infiltration Characteristic Modeling Using FLOW-3D within a Modular Pavement, Procedia Engineering, Volume 50, 2012, Pages 658-667, ISSN 1877-7058, 10.1016/j.proeng.2012.10.072.

65-12  X.H. Yang, T.J. Lu, T. Kim, Influence of non-conducting pore inclusions on phase change behavior of porous media with constant heat flux boundaryInternational Journal of Thermal Sciences, Available online 10 October 2012. Available online at SciVerse.

56-12  Giancarlo Alfonsi, Agostino Lauria, Leonardo Primavera, Flow structures around large-diameter circular cylinder, Journal of Flow Visualization and Image Processing, DOI: 10.1615/JFlowVisImageProc.2012005088, 2012. Available for purchase online at Begell Digital Library.

49-12  M. Janocko, M.B.J. Cartigny, W. Nemec, E.W.M. Hansen, Turbidity current hydraulics and sediment deposition in erodible sinuous channels: laboratory experiments and numerical simulations, Marine and Petroleum Geology, Available online 17 September 2012. Available for purchase online at SciVerse.

32-12  Fatih Karadagli, Bruce E. Rittmann, Drew C. McAvoy, and John E. Richardson, Effect of Turbulence on the Disintegration Rate of Flushable Consumer Products, Water Environment Research, Volume 84, Number 5, May 2012

31-12    D. Valero Huerta and R. García-Bartual, Optimization of Air Conditioning Diffusers Location in Large Agricultural Warehouses Using CFD Techniques, International Conference of Agricultural Engineering (CIGR-AgEng2012) Valencia, Spain, July 8-12, 2012

16-12 Yi Fan Fu, Wei Dong, Ying Li, Yi Tan, Ming Hui Yi, Akira Kawasaki, Simulation of the Effects of the Physical Properties on Particle Formation of Pulsated Orifice Ejection Method (POEM), 2012, Advanced Materials Research, 509, 161. Available for purchase online at Scientific.Net.

92-11  Giancarlo Alfonsi, Agostino Lauria, Leonardo Primavera, The lower vertical structure past the Ahmed car model, International Conference on Computational Science, ICCS 2011. Available for purchase online at Begell Digital Library.

80-11  Ismail Abustan, Meor Othman Hamzah, Mohd Aminur Rashid, A 3-Dimensional Numerical Study of a Flow within a Permeable Pavement, OIDA International Conference on Sustainable Development, ISSN 1923-6670, Putrajaya, Malaysia, 5-7th December 2011

66-11   H. Kondo, T. Furukawa, Y. Hirakawa, K. Nakamura, M. Ida, K.Watanabe, T. Kanemura, E. Wakai, H. Horiike, N. Yamaoka, H. Sugiura, T. Terai, A. Suzuki, J. Yagi, S. Fukada, H. Nakamura, I. Matsushita, F. Groeschel, K. Fujishiro, P. Garin and H. Kimura, IFMIF-EVEDA lithium test loop design and fabrication technology of target assembly as a key componentNuclear Fusion Volume 51 Number 12, doi:10.1088/0029-5515/51/12/123008

49-11     N.I. Vatin, A.A. Girgidov, K.I. Strelets, Numerical modelling the three-dimensional velocity field in the cyclone, Inzhenerno-Stroitel’nyi Zhurnal, No. 4, 2011. In Russian.

41-11    Maiko Hosoda, Taichi Hirano, and Keiji Sakai, Low-Viscosity Measurement by Capillary Electromagnetically Spinning Technique, © 2011 The Japan Society of Applied Physics, Japanese Journal of Applied Physics, July 20, 2011.

18-11  Ortloff, C.R., Vogel, M., Spray cooling heat transfer — Test and CFD analysis, Semiconductor Thermal Measurement and Management Symposium (SEMI-THERM), 2011 27th Annual IEEE, 20-24 March 2011, pp 245 – 252, San Jose, CA, 10.1109/STHERM.2011.5767208.

82-10   Dr. John Abbott, Two problems on the flow of viscous sheets of molten glass, 26th Annual Workshop on Mathematical Problems in Industry, Rensselear Polytechnic Institute, June 14-18, 2010

57-10  Chouet, B. A., Dawson, P. B., James, M. R. and Lane, S. J., Seismic source mechanism of degassing bursts at Kilauea Volcano, Hawaii: Results from waveform inversion in the 10–50 s band, J. Geophys. Res., 115, B09311, doi:10.1029/2009JB006661, September 2010. Available online at JOURNAL OF GEOPHYSICAL RESEARCH.

55-10 Pamela Waterman, FEA and CFD: Getting Better All the Time, Desktop Engineering, December 2010.

53-10  Nicolas Fries, Capillary transport processes in porous materials – experiment and model, Cuvillier Verlag Göttingen; 2010; ISBN 978-3-86955-507-2. Available at www.cuvillier.de  and www.amazon.de.

45-10  Meiring Beyers, Thomas Harms, and Johan Stander, Mitigating snowdrift at the elevated SANAE IV research station in Antarctica CFD simulation and field application, The Fifth International Symposium on Computational Wind Engineering (CWE2010), Chapel Hill, North Carolina, USA, May 23-27, 2010.

31-10 J. Spangenberg, N. Roussel, J.H. Hattel, J. Thorborg, M.R. Geiker, H. Stang and J. Skocek, Prediction of the Impact of Flow-Induced Inhomogeneities in Self-Compacting Concrete (SCC), Ch. 25 of “Design, Production and Placement of Self-Consolidating Concrete,” RILEM Bookseries, 2010, Volume 1, Part 5, 209-215, DOI: 10.1007/978-90-481-9664-7_18. Available online at Springer Link.

28-10 Sirisha Burra, Daniel P. Nicolella, W. Loren Francis, Christopher J. Freitas, Nicholas J. Mueschke, Kristin Poole, and Jean X. Jiang, Dendritic processes of osteocytes are mechanotransducers that induce the opening of hemichannels, Proc Natl Acad Sci U S A. 2010 Jul 19. [Epub ahead of print], Available for purchase at PNAS.

19-10 Michael T. Tolley, Michael Kalontarov, Jonas Neubert, David Erickson and Hod Lipson, Stochastic Modular Robotic Systems A Study of Fluidic Assembly Strategies, IEEE Transactions on Robotics, Vol. 26, NO. 3, June 2010

59-17   Han Eol Park and In Cheol Bang, Design study on mixing performance of rotational vanes in subchannel with fuel rod bundles, Transactions of the Korean Nuclear Society Autumn Meeting, Gyeongju, Korea, October 26-27, 2017.

44-09 Micah Fuller, Fabian Bombardelli, Deb Niemeier, Particulate Matter Modeling in Near-Road Vegetation Environments, Contract AQ-04-01: Developing Effective and Quantifiable Air Quality Mitigation Measures, UC Davis, Caltrans, September 2009

28-09 D. C. Lo, Dong-Taur Su and Jan-Ming Chen (2009), Application of Computational Fluid Dynamics Simulations to the Analysis of Bank Effects in Restricted Waters, Journal of Navigation, 62, pp 477-491, doi:10.1017/S037346330900527X; Purchase the article online (clicking on this link will take you to the Cambridge Journals website).

24-09 Richard C. Givler and Mario J. Martinez, Modeling of Pulsating Heat Pipes, Sandia Report, SAND2009-4520, Sandia National Laboratories, August 2009.

45-08  J. Saeki, Seikei Kakou, Three-Dimensional Flow Analysis of a Thermosetting Compound in a Motor Stator, 20, 750-754 (2008) [in Japanese] (Zipped file contains paper and appendices)

38-08 Yoshifumi Kuriyama, Ken’ichi Yano and Masafumi Hamaguchi, Trajectory Planning for Meal Assist Robot Considering Spilling Avoidance, 17th IEEE International Conference on Control Applications, Part of 2008 1EEE Multi-conference on Systems and Control, San Antonio, Texas, September 3-5, 2008

29-08 Ernst W.M. Hansen, Wojciech Nemec and Snorre Heimsund, Numerical CFD simulations — a new tool for the modelling of turbidity currents and sand dispersal in deep-water basins, Production Geoscience 2008 in Stavanger, Norway, © 2008

17-08 James, M. R., Lane, S. J. & Corder, S. B., Modelling the rapid near-surface expansion of gas slugs in low-viscosity magmas, In Lane S. J., Gilbert J. S. (eds) Fluid Motion in Volcanic Conduits: A Source of Seismic and Acoustic Signals. Geol. Soc., London, Spec. Pub., 307, 147-167, doi: 10.1144/SP307.9. 2008

16-08 Stefano Malavasi, Nicola Trabucchi, Numerical Investigation of the Flow Around a Rectangular Cylinder Near a Solid Wall, BBAA VI International Colloquium on: Bluff Bodies Aerodynamics & Applications, Milano, Italy, July 2008

41-07 Nicolas Roussel, Mette R. Geiker, Frederic Dufour, Lars N. Thrane and Peter Szabo, Computational modeling of concrete flow General Overview, Cement and Concrete Research 37 (2007) 1298-1307, © 2007 Elsevier Ltd.

40-07 Nemec, W., Heimsund, S., Xu, J. & Hansen, E.W.M., Numerical CFD simulation of turbidity currents, British Sedimentological Research Group (BSRG) Annual Meeting, Birmingham, 17-18 December 2007

39-07 Heimsund, S, Xu, J. & Nemec, W., Numerical Simulation of Recent Turbidity Currents in the Monterey Canyon System, Offshore California, American Geophysical Union Fall Meeting, 10-14 December 2007

32-07 James, M. R., Lane, S. J. & Corder, S. B., Modeling the near-surface expansion of gas slugs in basaltic magmaEos Trans. A.G.U., 88(52), Fall Meet. Suppl.. Abs. V12B-03. 2007

31-07 James, M. R., Lane, S. J. and Corder, S. B., Degassing low-viscosity magma: Quantifying the transition between passive bubble-burst and explosive activityE.G.U. Geophys. Res. Abstr., 905336, SRef-ID: 1607-7962/gra/EGU2007-A-05336. 2007

35-06  S. Green and C. Manepally, Software Validation Report for FLOW-3D Version 9.0, Center for Nuclear Waste Regulatory Analyses, August 2006

33-06 N. Roussel, Correlation between yield stress and slump: Comparison between numerical simulations and concrete rheometers results, © RILEM 2006, Materials and Structures (2006) 39:501-509, Purchase online at Springer Link.

32-06 Heimsund, S., Möller, N. and Guargena, C., FLOW-3D simulation of the Ormen Lange field, mid-Norway, In: Hoyanagi, K., Takano, O. and Kano, K. (Ed.), Abstracts, International Association of Sedimentologists 17th International Sedimentological Congress, Fukuoka, Vol. B, p. 107, 2006

10-06 Gengsheng Wei, An Implicit Method to Solve Problems of Rigid Body Motion Coupled with Fluid Flow, Flow Science Technical Note #76, FSI-05-TN76.

8-06 Gengsheng Wei, Three-Dimensional Collision Modeling for Rigid Bodies and its Coupling with Fluid Flow Computation, Flow Science Technical Note #75, FSI-06-TN75.

34-05  Young Bae Kim, Kyung Do Kim, Sang Eui Hong, Jong Goo Kim, Man Ho Park, and Ju Hyun Kim, and Jae Keun Kweon, 3D Simulation of PU Foaming Flow in a Refrigerator Cabinet, Appliance Magazine.com, January 2005.

33-05 N. Roussel, Fifty-cent rheo-meter for yield stress measurements From slump to spreading flow, @2005 by The Society of Rheolgoy, Inc., J. Rheol. 49(3), 705-718 May/June (2005)

32-05 Heimsund, S., Möller, N., Guargena, C. and Thompson, L., Field-scale modeling of turbidity currents by FLOW-3D simulations, In: Workshop Abstracts, Modeling of Turbidity Currents and Related Gravity Currents, University of California, Santa Barbara, 2 p., (2005)

15-05 Gengsheng Wei, A Fixed-Mesh Method for General Moving Objects, Flow Science Technical Note #73, FSI-05-TN73

14-05 James M. Brethour, Incremental Thermoelastic Stress Model, Flow Science Technical Note #72, FSI-05-TN72

9-05 Gengsheng Wei, A Fixed-Mesh Method for General Moving Objects in Fluid Flow, Modern Physics Letters B, Vol. 19, Nos. 28-29 (2005) 1719-1722

1-05 C.W. Hirt, Electro-Hydrodynamics of Semi-Conductive Fluids: With Application to Electro-Spraying Flow Science Technical Note #70, FSI-05-TN70

35-04  J. Saeki, T. Kono and T. Teramae, Seikei Kakou, Formulation of Mathematical Models for Estimating Residual Stress and Strain Components Correlated with 3-D Flow of Thermosetting Compounds, 16, 5, 309-316 (2004) [in Japanese]. (Zipped file contains paper and appendices)

31-04 Heimsund, S., Möller, N., Guargena, C. and Thompson, L., The control of seafloor topography on turbidite sand dispersal in the Ormen Lange field: a large-scale application of FLOW-3D simulations, In: Martinsen, O.J. (Ed.), Abstracts and Proceedings of the Geological Society of Norway (NGF), Deep Water Sedimentary Systems of Arctic and North Atlantic Margins, Stavanger, 3, p. 25, (2004)

26-04 Beyers, J.H.M., Harms, T.M. and Sundsbø, P.A., 2004, Numerical simulation of three dimensional, transient snow drifting around a cube, Journal of wind engineering and industrial aerodynamics, vol. 92, pp. 725-747, ISSN 0167-6105

25-04 Beyers, J.H.M, Harms, T.M. and Sundsbø, P.A., 2004, Numerical simulation of snow drifting around an elevated obstacle, Proceedings of the 5th conference on snow engineering, Davos, Switzerland, pp.185-191

17-04 Michael Barkhudarov, Multi-Block Gridding Technique for FLOW-3D (Revised), Flow Science Technical Note #59-R2, FSI-00-TN59-R2

36-03 Heimsund, S., Hansen, E.W.M. and Nemec, W., Numerical CFD simulation of turbidity currents and comparison with laboratory data, In: Hodgetts, D., Hodgson, D. and Smith, R. (Ed.), Slope Modelling Workshop Abstracts, Experimental, Reservoir and Forward Modelling of Turbidity Currents and Deep-Water Sedimentary Systems, Liverpool Univ., p. 13., (2003b)

35-03 Heimsund, S., Hansen, E.W.M. and Nemec, W. Computational 3-D fluid-dynamics model for sediment transport, erosion and deposition by turbidity currents, In: Nakrem, H.A. (Ed.), Abstracts and Proceedings of the Geological Society of Norway (NGF), Den 18. Vinterkonferansen, Oslo, 1, p. 39., (2003a)

33-03 Beyers, J.H.M., Sundsbø, P.A. and Harms, T.M., 2003, Numerical simulation and verification of drifting snow around a cube, Proceedings of the 11th international conference on wind engineering, Texas Tech University, Lubbock, Texas, USA, pp. 1886-1893

27-03 Jun Zeng, Daniel Sobek and Tom Korsmeyer, Electro-Hydrodynamic Modeling of Electrospray Ionization CAD for a µFluidic Device-Mass Spectrometer Interface, Agilent Technologies Inc, paper presented at Transducers 2003, June 03 Boston (note: Reference #10 is to FLOW-3D)

25-03 J. M Brethour, Moving Boundaries an Eularian Approach, Moving Boundaries VII, Computational Modelling of Free and Moving Boundary Problems, A. A. Mammoli & C.A. Brebbia, WIT Press

19-03 James Brethour, Incremental Elastic Stress Model, Flow Science Technical Note (FSI-03-TN64)

18-03 Michael Barkhudarov, Semi-Lagrangian VOF Advection Method for FLOW-3D, Flow Science Technical Note (FSI-03-TN63)

11-02 Junichi Saeki and Tsutomu Kono, Three-Dimensional Flow Analysis of a Thermosetting Compound during Mold Filling, Polymer Processing Society 18th Annual Meeting, June 2002, Guimares, Portugal.

46-01 Yasunori Iwai, Takumi Hayashi, Toshihiko Yamanishi, Kazuhiro Kobayashi and Masataka Nishi, Simulation of Tritium Behavior after Intended Tritium Release in Ventilated Room, Journal of Nuclear Science and Technology, Vol. 38, No. 1, p. 63-75, January 2001

23-01 Borre Bang, Dag Lukkassen, Application of Homogenization Theory Related to Stokes Flow in Porous Media, Applications of Mathematics, Narvik, Norway, No 4, pp. 309-319.

15-01 Ernst Hansen, SINTEF Energy Research, Trondheim, Norway, Computer Simulation Helps Increase Flow Rate in Three-Phase Separator, Drilling Marketplace, Vol 55, No 10, May 15, 2001, pp.14

10-01 Ernst Hansen, SINTEF Energy Research, Phenomeological Modeling and Simulation of Fluid Flow and Separation Behaviour in Offshore Gravity Separators, PVP-Col 431, Emerging Technologies for Fluids, Structures and Fluids, Structures and Fluid Structure Interaction — 2001, ASME 2001, pp. 23-29

7-01 C. Bohm, D. A. Weiss, and C. Tropea, Multi-droplet Impact onto Solid Walls Droplet-droplet Interaction and Collision of Kinemeatic Discontinuities, DaimlerChrysler Research and Technology, ILASS-Europe 2000, September 11-13, 2000

6-01 Ernst Hansen, Simulation Raises Separator Flow RateEngineering Talk, March 21, 2001

3-01 M. Sick, H. Keck, G. Vullioud, and E. Parkinson, New Challenges in Pelton Research

1-01 Y. Darsht, K. Kuvanov, A. Puzanov, I. Kholkin, FLOW-3D in Designing Hydraulic Systems for Heavy Machinery  (in Russian), SAPR I Grafika (CAD and Graphics), August 2000, pp. 50-55.

22-00 A. K. Temu, O. K. Sønju and E. W. M. Hansen, Criteria for Minimum Particle Deposition onto a Cylinder in Crossflow, International Symposium on Multiphase Flow and Transport Phenomena, November 2000, Tekirova, Antalya, Turkey

21-00 Claus Maier, Stefan aus der Wiesche and Eberhard P. Hofer, Impact of Microdrops on Solid Surfaces for DNA-Synthesis, Department of Measurement, Control and Microtechnology, University of Ulm, Technical Proceedings of the 2000 International Conference on Modeling and Simulation of Microsystems, pp. 586-589

11-00 Thomas K. Thiis, A Comparison of Numerical Simulations and Full-scale Measurements of Snowdrifts around Buildings, Wind and Structures – ISSN: 1226-6116,Vol. 3, nr. 2 (2000), pp. 73-81

10-00 P.A. Sundsbo and B. Bang, Snow drift control in residential areas-Field measurements and numerical simulations, Fourth International Conference on Snow Engineering, pp. 377-382

9-00 Thomas K. Thiis and Christian Jaedicke, The Snowdrift Pattern Around Two Cubical Obstacles with Varying Distance—Measurement and Numerical Simulations, Snow Engineering, edited by Hjorth-Hansen, et al, Balkema, Rotterdam, 2000, pp.369-375.

8-00 Thomas K. Thiis and Christian Jaedicke, Changes in the Snowdrift Pattern Caused by a Building Extension—Investigations Through Scale Modeling and Numerical Simulations, Snow Engineering, edited by Hjorth-Hansen, et al, Balkema, Rotterdam, 2000, pp. 363-368

7-00 Bruce Letellier, Louis Restrepo, and Clinton Shaffer, Near-Field Dispersion of Fission Products in Complex Terrain Using a 3-D Turbulent Fluid-Flow Model, CCPS International Conference, San Francisco, CA, September 28-October 1, 1999

6-00 Bruce Letellier, Patrick McClure, and Louis Restrepo, Source-Term and Building-Wake Consequence Modeling for the GODIVA IV Reactor at Los Alamos National Laboratory, 1999 Safety Analysis Workshop, Portland, Oregon, June 13-18, 1999

11-99 Thomas K. Thiis and Yngvar Gjessing, Large-scale Measurements of Snowdrifts Around Flat-roofed and Single-pitch-roofed Buildings, Cold Regions Science and Technology 30, Narvik, Norway, May 17, 1999, pp. 175-181

3-99 A. A. Gubaidullin, Jr., T. N. Dinh, and B. R. Sehgal, Analysis of Natural Convection Heat Transfer and Flows in Internally Heated Stratified Liquid, accepted for publication 33rd Natl. Heat Transfer Conf. CD proceedings, Albuquerque, NM, August 15-17, 1999

20-98 Mark W. Silva, A Computational Study of Highly Viscous Impinging Jets, published by the Amarillo National Resource Center for Plutonium, ANRCP-1998-18, November 1998

17-98 P. A. Sundsbo and B. Bang, 1998, Calculation of Snowdrift Around Roadside Safety Barriers, Proc of the International Snow Science Workshop, Sept. 1998, Sunriver, Oregon, USA 279-283

11-98 P-A Sundsbo, Numerical simulations of wind deflection fins to control snow accumulation in building steps, Journal of Wind Engineering and Industrial Aerodynamics 74-76 (1998) 543-552

23-97  P.E. O’Donoghue, M.F. Kanninen, C.P. Leung, G. Demofonti, and S. Venzi, The development and validation of a dynamic propagation model for gas transmission pipelines, Intl J. Pres. Ves. & Piping 70 (1997) 11-25, P11 : S0308 – 0161 (96) 00012 – 9.

22-97  Christopher J. Matice, Simulation of High Speed Filling, Presented at High Speed Processing & Filling of Plastic Containers, SME, Chicago, Illinois, November 11, 1997.

12-97 B. Entezam and W. K. Van Moorhem, University of Utah, Salt Lake City, UT and J. Majdalani, Marquette University, Milwaukee, WI, Modeling of a Rijke-Tube Pulse Combustor Using Computational Fluid Dynamics, presented at 33rd AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, Seattle, WA, July 6-9, 1997.

11-97 B. Entezam, Computational and Experimental Investigation of Unsteady Flowfield Inside the Rijke Tube, doctoral thesis submitted to University of Utah, Dept. Mechanical Engineering, Salt Lake City, UT, June 1997

2-97 K. Fujisaki, T. Ueyama, and K. Okazawa, Magnetohydrodynamic Calculation of In-Mold Electromagnetic Stirring, Nippon Steel Corp., IEEE Transactions on Magnetics, Vol. 33, No. 2, March 1997

1-97 P. A. Sundsbo, Four Layer Modelling and Numerical Simulations of Snow Drift, to be submitted to the Journal of Glaciology, 1997

23-96 Andy K Palmer, Computational Fluid Dynamic Software Comparison and Electrostatic Precipitator Modeling, Presented to the Faculty of California State University, Summer 1996

21-96 P. A. Sundsbo, Computer Simulation of Snow-Drift around Structures, Proceedings of the 4th Symposium on Building Physics in the Nordic Countries, Vol. 2, 533-539, Finland, 9-10 Sep. 1996

20-96 P. A. Sundsbo and E.W.M. Hansen, Modelling and Numerical Simulation of Snow-Drift around Snow Fences, Proceedings of the 3rd International Conference on Snow Engineering, Sendai, Japan, 26-31 May 1996

19-96 P. A. Sundsbo, Numerical Modelling and Simulation of Snow Accumulations around Porous FencesProceedings of the International Snow Science Workshop, Banff, Alberta, Canada, 6-10 Oct. 1996

18-96 T. Iverson, Editor, Applied Modelling and Simulation, Proceedings of the 38th SIMS Simulation Conference, Norwegian University of Science and Technology, Trondheim, Norway, June 11-13, 1996

17-96 C. L. Parish, Modeling Compressible Flow Through an Orifice Stack Using Numerical Methods, thesis submitted for M.S. Mech. Engineering, NM State University, Las Cruces, NM, December 1996

15-96 T. Wiik and R. K. Calay, A Study of Balcony on Flow-Field and Wind Loads for Low-Rise Buildings, Fourth Symposium on Building Physics in the Nordic Countries, Dipoli, Espoo, Finland, September 1996

14-96 T. Wiik, E.W.M. Hansen, The Assessment of Wind Loads on Roof Overhang of Low-Rise Buildings, Second International Symposium Wind Engineering, Fort Collins, CO, September 1996

13-96 T. Wiik, R. K. Calay, and A. Holdo, A Study of Effects of Eaves on Flow-Field and Wind Loads for Low-Rise Houses, Third International Colloquium on Bluff Body Aerodynamics and Applications, Blacksburg, Virginia, August 1996

11-96 Y. Miyamoto and M. Harada, A Flow Analysis accompanied by Formation of the Liquid Droplets shown with an Animation Display Technique, SEA Corporation, presented at Visualization Information Conference, Tokyo, Japan, July 17, 1996

8-96 J. Bakken, E. Naess, T. Engebretsen, and E. W. M. Hansen, Fluid Flow in Porous Media, proceedings of the 38th SIMS Simulations Conference, Norwegian Univ. of Science & Technology, Trondheim, Norway, June 11-13, 1996

7-96E. W. M. Hansen, Performance of Oil/Water Gravity Separators Imposed to Motion, proceedings of the 38th SIMS Simulations Conference, Norwegian Univ. of Science & Technology, Trondheim, Norway, June 11-13, 1996

8-95 J. J. Francis, Computational Hydrodynamic Study of Flow through a Vertical Slurry Heat Exchanger, NSF Summer Research Program, Dept. Mech. Engineering, Univ. of Nevada Las Vegas, August 9, 1995

4-94 J. L. Ditter and C. W. Hirt, A Scalable Model for Mixing Vessels, Flow Science report, FSI-94-00-1, presented at the 1994 ASME Fluids Engineering Summer Meeting, Incline Village, NV, June 1994

3-94 A. Nielsen, B. Bang, P. A. Sundsbo and T. Wiik, Computer Simulation of Windspeed, Windpressure and Snow Accumulation around Buildings (SNOW-SIM), 1st International Conference on HVAC in Cold Climate, Rovaniemi, Finland, from Narvik Institute of Technology, Narvik, Norway, March 1994

2-94 J. M. Sicilian, Addition of an Extended Bubble Model to FLOW-3D, Flow Science report, FSI-94-58-1, March 1994

1-94 T. Hong, C. Zhu, P. Cal and L-S Fan, Numerical Modeling of Basic Modes of Formation and Interactions of Bubbles in Liquids, Dept. Chem. Engineering, Ohio State University, Columbus, OH 43210, March 1994

14-93 J. L. Ditter and C. W. Hirt, A Scalable Model for Stir Tanks, Flow Science Technical Note #38, December 1993 (FSI-93-TN38)

13-93 J. Partinen, N. Saluja and J. K. Kirtley, Jr., Experimental and Computational Investigation of Rotary Electromagnetic Stirring in a Woods Metal System, Dept. of Math, Science and Engr. and Dept. of Electrical Engr. and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139-4307

12-93 J. Partinen, N. Saluja and J. K. Kirtley, Jr., Modeling of Surface Deformation in an Electromagnetically Stirred Metallic Melt, Dept. of Math, Science, and Engr. and Dept. of Electrical Engr. and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139-4307

10-93 C. Philippe, Summary Report on Test Calculations with FLOW-3D/CAST93, (coupled-rigid-body dynamics model), ESTEC, Noordwijk, The Netherlands, September 17, 1993

5-93 J. M. Sicilian, J. L. Ditter and C. L. Bronisz, FLOW-3D Analyses of CFD Triathlon Benchmark, Flow Science report, presented at the ASME Fluids Engineering Conference, Washington DC, June 20-24, 1993

4-93 T. Wiik, Ventilation of the Attic due to Wind Loads on Low-Rise Buildings, paper for 3rd Symposium of Building Physics in Nordic Countries, Narvik Institute of Technology, Narvik, Norway, summer 1993

3-93 E. W. M. Hansen, Modelling and Simulation of Separation Effects and Fluid Flow Behaviour in Process-Units, SIMS’93 – 35th Simulation Conference, Kongsberg, Norway, June 9-11, 1993

2-93 M. A. Briones, R. S. Brodsky and J. J. Chalmers, Computer Simulation of the Rupture of a Gas Bubble at a Gas-Liquid Interface and its Implications in Animal Cell Damage, Dept. Chemical Engineering, Ohio State University, Manuscript No. RB68, April 1993

11-92 G. Trapaga, E. F. Matthys, J. J. Valencia and J. Szekely, Fluid Flow, Heat Transfer, and Solidification of Molten Metal Droplets Impinging on Substrates: Comparison of Numerical and Experimental Results, Metallurgical Transactions B, Vol. 23B, pp. 701-718, December 1992

10-92 J. B. Dalin, J. M. Le Guilly, P. Le Roy and E. Maas, Numerical Simulations Applied to the Production of Automotive Foundry Components, Numerical Methods in Industrial Forming Processes, Wood & Zienkiewicz (eds), Balkema, Rotterdam, 1992

5-92 C. W. Hirt, Volume-Fraction Techniques: Powerful Tools for Flow Modeling, Flow Science report (FSI-92-00-02), presented at the Computational Wind Engineering Conference, University of Tokyo, August 1992

3-92 C. L. Bronisz and C.W. Hirt, Lubricant Flow in a Rotary Lip Seal, Flow Science Technical Note #33, February 1992 (FSI-92-TN33)

16-91 A. Nielsen, SNOW-SIM – Computer Model for Simulation of Wind and Snow Loads on Buildings and Structures, Building Science, Narvik Institute of Technology, Narvik, Norway, (not dated)

15-91 E. W. M. Hansen, H. Heitmann, B. Laska, A. Ellingsen, O. Ostby, T. B. Morrow and F. T. Dodge, Fluid Flow Modelling of Gravity Separators, SINTEF, Norway and Southwest Research Institute, Texas, Elsevier Science Publishers, 1991

14-91 E. W. M. Hansen, H. Heitmann, B. Laska and M. Loes, Numerical Simulation of Fluid Flow Behaviour Inside, and Redesign of a Field Separator, SINTEF, Norway and STATOIL, Norway (not dated)

13-91 G. Trapaga and J. Szekely, Mathematical Modeling of the Isothermal Impingement of Liquid Droplets in Spraying Processes, Metallurgical Transactions, Vol. 22B, pp. 901-914, December 1991

11-91 N. Saluja and J. Szekely, Velocity Fields and Free Surface Phenomena in an Inductively Stirred Mercury Pool, European Journal of Mechanics, B/Fluids, Vol. 10, No. 5, pp. 563-572, Oct. 1991

4-90 J. M. Sicilian, A Note on Implementing Specified Velocities and Momentum Sources, Flow Science report, September 1990 (FSI-90-00-5)

13-90 P. Jonsson, N. Saluja, O. J. Ilegbusi, and J. Szekely, Fluid Flow Phenomena in the Filling of Cylindrical Molds Using Newtonian (Turbulent) and Non-Newtonian (Power Law) Fluids, submitted to Trans. of the American Foundrymen’s Soc., June 1990

12-90 N. Saluja, O. J. Ilegbusi, and J. Szekely, On the Computation of the Velocity Fields and the Dynamic Free Surface Generated in a Liquid Metal Column by a Rotating Magnetic Field, submitted to J. Fluid Mech., July 1990

7-90 C. L. Bronisz and C. W. Hirt, Modeling Unsaturated Flow in Porous Media: A FLOW-3D Extension, Flow Science report, July 1990 (FSI-90-48-2)

5-90 C. L. Bronisz and C. W. Hirt, Hydrodynamic Ram Simulations Using FLOW-3D, Flow Science report, May 1990 (FSI-90-49-1)

3-90 C. W. Hirt, Turbojet Plume Flow Analysis, Flow Science report, February 1990 (FSI-90-45-1)

5-89 K. S. Eckhoff and E. W. M. Hansen, Mathematical Modelling and Numerical Investigation of Separation in Two-Phase Rotating Flow, SINTEF-Foundation for Scientific and Industrial Research at the Norwegian Institute of Technology, Trondheim, Norway, Report No. OR 22 1907.00.01.89, 29 April 1989

2-89 J. M. Sicilian and J. R. Tegart, Comparisons of FLOW-3D Calculations with Very Large Amplitude Slosh Data, presented at the Symposium on Computational Experiments, PVP ASME Conference, Honolulu, HI, July 22-27, 1989

2-88 J. M. Sicilian and C. W. Hirt, AFT Field Joint: CFD Analysis Using the FLOW-3D Program, in Redesigned Solid Rocket Motor Circumferential Flow Technical Interchange Meeting Final Report, NASA-TWR-17788, February 1988

14-87 C. J. Freitas, S. T. Green, and T. B. Morrow, Fluid Dynamics Associated with Ductile Pipeline Fracture, Southwest Research Institute report presented at ASME Winter Annual Meeting, Boston, MA, December 1987

13-87 J. Sicilian, The FLOW-3D Model for Thermal Conduction in Solids, Flow Science report, Dec. 1987 (FSI-87-00-4)

7-87 C.W. Hirt, Vectored Nozzle Flow with Turbulence Modeling, Flow Science report, Sept. 1987 (FSI-87-29-1)

4-87 J.M. Sicilian, C.W. Hirt, and R. P. Harper, FLOW-3D: Computational Modeling Power for Scientists and Engineers, Flow Science report, 1987 (FSI-87-00-1)

3-86 J. M. Sicilian, Natural-Convection Heat-Transfer Analysis, Flow Science Technical Note #4, June 1986 (FSI-86-00-TN4)

2-86 J. Navickas and C. R. Cross, Air Circulation Characteristics and Convective Losses in a 5-MW Molten Salt Cavity Solar Receiver, ASME 8th Annual Conference on Solar Engineering, Anaheim, California, April 13-16, 1986

5-85 C. W. Hirt and R. P. Harper, Calculations of Vent Clearing in a Chemical Process Tank, Flow Science report, December 1985 (FSI-85-28-1)

2-84 Applications of SOLA-3D/FSI to Fluid Slosh, Flow Science report, May 1984

Automotive Bibliography

다음은 자동차 관련 기술 문서 모음입니다.
이 모든 논문은 FLOW-3D  결과를 포함하고 있습니다. FLOW-3D  를 사용하여 자동차 산업의 어플리케이션을 성공적으로 시뮬레이션  하는 방법에 대해 자세히 알아보십시오.

Below is a collection of technical papers in our Automotive Bibliography. All of these papers feature FLOW-3D results. Learn more about how  FLOW-3D can be used to successfully simulate applications for the Automotive Industry.

2024년 3월 20일 Update

159-22 Shihao Li, Yan Yan, Wei Wei, Zhao Wang, Zhonghua Ni, Numerical simulation on the thermal dynamic behavior of liquid hydrogen in a storage tank for trailers, Case Studies in Thermal Engineering, 40; 102520, 2022. doi.org/10.1016/j.csite.2022.102520

53-22   Ilias Papadimitriou, Michael Just, Manufacturing of structural components for internal combustion engine, electric motor and battery using casting and 3D printing, Advances in Engine and Powertrain Research and Technology, Mechanisms and Machine Science 114, Ed. Tigran Parikyan, 2022. doi.org/10.1007/978-3-030-91869-9_15

33-21   Xiaozhou Hu Ao Wang Pingping Li Jianing Wang, Influence of dynamic attitudes on oil supply for bearings and churning power losses in a splash lubricated spiral bevel gearbox, Tribology International, 159; 106951, 2021. doi.org/10.1016/j.triboint.2021.106951

64-18   Vasilios Fourlakidis, Ilia Belov and Attila Diószegi, Strength prediction for pearlitic lamellar graphite iron: Model validation, Metals, Vol. 8, No. 9, 2018. doi.org/10.3390/met8090684

43-18   R.A. Ibrahim and B. Singh, Assessment of ground vehicle tankers interacting with liquid sloshing dynamics, International Journal of Heavy Vehicle Systems, vol. 25, no. 1, 2018. doi.org/10.1504/IJHVS.2018.089894

34-17   Hidenori Arisawa, Yuji Shinoda, Mitsuaki Tanaka, Tatsuhiko Goi, Hirofumi Akahori and Mamoru Yoshitomi, Classification of Fluid Dynamic Loss in Aeroengine Transmission Gears – Experimental Analysis and CFD Validation, Proceedings of ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition, GT2017, June 26-30, 2017, Charlotte, NC, USA.

26-15   Herbert Obame Mve, Romuald Rullière and Philippe Haberschill, Modeling and Parametric Study of the Heat Transfer Inside a Lithium Bromide Flow Confined by Wire Screen, Journal of Energy and Power Engineering 9 (2015) 417-425, doi: 10.17265/1934-8975/2015.05.001

17-15   Peyman Jafarian, Gear interlocking effect study using CFD, published online April 2015.

23-14  Daiki Saegusa and Shinji Kawai, CFD Analysis of Lubricant Fluid Flow in Automotive Transmission, SAE Technical Paper 2014-01-1772, 2014, doi:10.4271/2014-01-1772, Copyright © 2014 SAE International.

15-14  Hidenori Arisawa, Motohiko Nishimura, Hideyuki Imai and Tatsuhiko Goi, CFD Simulations and Experiments for Reduction of Oil Churning Loss and Windage Loss in Aeroengine Transmission Gears, Journal of Engineering for Gas Turbines and Power, ASME, doi:10.1115/1.4026952, 2014.

87-13 Daiki Saegusa and Shinji Kawai, Technique for Prediction of Automotive Transmission Lubrication Performance, Honda R&D Technical Review, October 2013.

26-13  Hidenori Arisawa, Motohiko Nishimura, Hideyuki Imai, Kenichiro Tanaka, and Tatsuhiko Goi, CFD Simulations and Experiments for Reduction of Oil Churning Loss and Windage Loss on Aeroengine Transmission Gears, No. 2012-JCT-0705, © 2013 The Japan Society of Mechanical Engineers. In Japanese.

53-09  Hidenori Arisawa, Motohiko Nishimura, Hideyuki Imai and Tatsuhiko Goi, CFD Simulation for Reduction of Oil Churning Loss and Windage Loss on Aeroengine Transmission Gears, ASME Turbo Expo 2009: Power for Land, Sea and Air, Orlando, Florida, USA, June 8-12, 2009.

45-09 Chih-Chung Chang, Sy-Chi Kuo, Chen-Kang Huang, and Sih-Li Chen, The Investigation of Motor Cooling Performance, International Journal of Mechanical, Industrial and Aerospace Engineering, 3:1, 2009.

37-04   U, H., Cleghorn, W. and Mills, J., Design and Analysis of Fuel Tank Baffles to Reduce the Noise Generated From Fuel Sloshing, SAE Technical Paper 2004-01-0403, 2004, doi:10.4271/2004-01-0403.

38-03   Hidenori Arisawa, Katsuya Umemoto, Atsushi Ueshima and Yuichi Kawamoto, CFD Simulation of the Lubricating Oil Flow in Motorcycle Oilpan, 2003 SAE/JSAE Small Engine Technology, Conference & Exhibition, Madison, Wisconsin, USA, September 15-18, 2003.

Coastal & Maritime Bibliography

Coastal & Maritime Bibliography

다음은 연안 및 해양 분야의 기술 문서 모음입니다.
이 모든 논문은 FLOW-3D  결과를 포함하고 있습니다. FLOW-3D를 사용하여 연안 및 해양 시설물을 성공적으로 시뮬레이션 하는 방법에 대해 자세히 알아보십시오.

2024년 3월 20일 Update

Below is a collection of technical papers in our Coastal & Maritime Bibliography. All of these papers feature FLOW-3D results. Learn more about how FLOW-3D can be used to successfully simulate Coastal & Maritime applications.

212-23   Feifei Cao, Mingqi Yu, Meng Han, Bing Liu, Zhiwen Wei, Juan Jiang, Huiyuan Tian, Hongda Shi, Yanni Li, WECs microarray effect on the coupled dynamic response and power performance of a floating combined wind and wave energy system, Renewable Energy, 219.2; 119476, 2023. doi.org/10.1016/j.renene.2023.119476

210-23   H. Omara, Sherif M. Elsayed, Karim Adel Nassar, Reda Diab, Ahmed Tawfik, Hydrodynamic and morphologic investigating of the discrepancy in flow performance between inclined rectangular and oblong piers, Ocean Engineering, 288.2; 116132, 2023. doi.org/10.1016/j.oceaneng.2023.116132

190-23   M.F. Ahmad, M.I. Ramli, M.A. Musa, S.E.G. Goh, C.W.M.N Che Wan Othman, E.H. Ariffin, N.A. Mokhtar, Numerical simulation for overtopping discharge on tetrapod breakwater, AIP Conference Proceedings, 2746.1; 2023. doi.org/10.1063/5.0153371

183-23   Youkou Dong, Enjin Zhao, Lan Cui, Yizhe Li, Yang Wang, Dynamic performance of suspended pipelines with permeable wrappers under solitary waves, Journal of Marine Science and Engineering, 11.10; 1872, 2023. doi.org/10.3390/jmse11101872

176-23   Guoxu Niu, Yaoyong Chen, Jiao Lu, Jing Zhang, Ning Fan, Determination of formulae for the hydrodynamic performance of a fixed box-type free surface breakwater in the intermediate water, Journal of Marine Science and Engineering, 11.9; 1812, 2023. doi.org/10.3390/jmse11091812

168-23   Yupeng Ren, Huiguang Zhou, Houjie Wang, Xiao Wu, Guohui Xu, Qingsheng Meng, Study on the critical sediment concentration determining the optimal transport capability of submarine sediment flows with different particle size composition, Marine Geology, 464; 107142, 2023. doi.org/10.1016/j.margeo.2023.107142

163-23   Ahmad Fitriadhy, Sheikh Fakruradzi, Alamsyah Kurniawan, Nita Yuanita, Anuar Abu Bakar, 3D computational fluid dynamic investigation on wave transmission behind low-crested submerged geo-bag breakwater, CFD Letters, 15.10; 2023. doi.org/10.37934/cfdl.15.10.1222

162-23   Ramtin Sabeti, Landslide-generated tsunami waves-physical and numerical modelling, International Seminar on Tsunami Research, University of Bath, 2023.

161-23   Duy Linh Du, Study on the optimal location for pile-rock breakwater in reducing wave height in Dong Hai District, Bac Lieu Province, Vietnam, Thesis, Can Tho University, 2023.

160-23   Duy Linh Du, Dai Bang Pham, Van Duy Dinh, Tan Ngoc Cao, Van Ty Tran, Gia Bao Tran, Hieu Duc Tran, Modelling the wave reduction effectiveness of pile-rock breakwater using FLOW-3D, (in Vietnamese) Journal of Materials and Construction, 13.04; 2023. doi.org/10.54772/jomc.04.2023.537

151-23 Zhiguo Zhang, Jinpeng Chen, Tong Ye, Zhengguo Zhu, Mengxi Zhang, Yutao Pan, Wave-induced response of seepage pressure around shield tunnel in sand seabed slope, International Journal of Geomechanics, 23.10; 2023. doi.org/10.1061/IJGNAI.GMENG-8072

147-23 Jiale Li, Jijian Lian, Haijun Wang, Yaohua Guo, Sha Liu, Yutong Zhang, FengWu Zhang, Numerical study of the local scour characteristics of bottom-supported installation platforms during the installation of a monopile, Ships and Offshore Structures, 2023. doi.org/10.1080/17445302.2023.2243700

144-23 Weixang Liang, Min Lou, Changhong Fan, Deguang Zhao, Xiang Li, Coupling effect of vortex-induced vibration and local scour of double tandem pipelines in steady current, Ocean Engineering, 286.1; 115495, 2023. doi.org/10.1016/j.oceaneng.2023.11549

136-23 Zegao Yin, Jiahao Li, Yanxu Wang, Haojian Wang, Tianxu Yin, Solitary wave attenuation characteristics of mangroves and multi-parameter prediction model, Ocean Engineering, 285.2; 115372, 2023. doi.org/10.1016/j.oceaneng.2023.115372

130-23 Sheng Wang, Chaozhe Yuan, Yuchi Hao, Xiaowei Yan, Feasibility analysis of laying and construction of deep-water dredging sinking pipeline, The 33rd International Ocean and Polar Engineering Conference, ISOPE-1-23-030, 2023.

127-23 Chen-Shan Kung, Ya-Cing You, Pei-Yu Lee, Siu-Yu Pan, Yu-Chun Chen, The air entrainment effect stability on the marine pipeline, The 33rd International Ocean and Polar Engineering Conference, ISOPE-I-23-242, 2023.

126-23 Yuting Wang, Zhaode Zhang, Yuan Zhang, Numerical simulationa and measurement of artificial flow creation in reclamation projects, The 33rd International Ocean and Polar Engineering Conference, ISOPE-1-23-168, 2023.

125-23 Chen-Shan Kung, Siu-Yu Pan, Pei-Yu Lee, Ya-Cing You, Yu-Chun Chen, Numerical simulation of wave motion on the submarine HDPE pipe system, The 33rd International Ocean and Polar Engineering Conference, ISOPE-I-23-327, 2023.

115-23 Qishun Li, Yanpeng Hao, Peng Zhang, Haotian Tan, Wanxing Tian, Linhao Chen, Lin Yang, Numerical study of the local scouring process and influencing factors of semi-exposed submarine cables, Journal of Marine Science and Engineering, 11.7; 1349, 2023. doi.org/10.3390/jmse11071349

113-23 Minxi Zhang, Hanyan Zhao, Dongliang Zhao, Shaolin Yue, Huan Zhou, Xudong Zhao, Carlo Gualtieri, Guoliang Yu, Numerical study of the flow at a vertical pile with net-like scour protection mat, Journal of Ocean Engineering and Science, 2023. doi.org/10.1016/j.joes.2023.06.002

108-23 Seyed A. Ghaherinezhad, M. Behdarvandi Askar, Investigating effect of changing vegetation height with irregular layout on reduction of waves using FLOW-3D numerical model, Journal of Hydraulic and Water Engineering, 1.1; pp.55-64, 2023. doi.org/10.22044/JHWE.2023.12844.1004

92-23 Tongshun Yu, Xingyu Chen, Yuying Tang, Junrong Wang, Yuqiao Wang, Shuting Huang, Numerical modelling of wave run-up heights and loads on multi-degree-of-freedom buoy wave energy converters, Applied Energy, 344; 121255, 2023. doi.org/10.1016/j.apenergy.2023.121255

85-23   Emilee A. Wissmach, Biomimicry of natural reef hydrodynamics in an artificial spur and groove reef formation, Thesis, Florida Institute of Technology, 2023.

81-23   Zhi Fan, Feifei Cao, Hongda Shi, Numerical simulation on the energy capture spectrum of heaving buoy wave energy converter, Ocean Engineering, 280; 114475, 2023. doi.org/10.1016/j.oceaneng.2023.114475

72-23   Zegao Yin, Fei Wu, Yingni Luan, Xuecong Zhang, Xiutao Jiang, Jie Xiong, Hydrodynamic and aeration characteristics of an aerator of a surging water tank with a vertical baffle under a horizontal sinusoidal motion, Ocean Engineering, 287; 114396, 2023. doi.org/10.1016/j.oceaneng.2023.114396

71-23   Erfan Amini, Mahdieh Nasiri, Navid Salami Pargoo, Zahra Mozhgani, Danial Golbaz, Mehrdad Baniesmaeil, Meysam Majidi Nezhad, Mehdi Neshat, Davide Astiaso Garcia, Georgios Sylaios, Design optimization of ocean renewable energy converter using a combined Bi-level metaheuristic approach, Energy Conversion and Management: X, 19; 100371, 2023. doi.org/10.1016/j.ecmx.2023.100371

70-23   Ali Ghasemi, Rouholla Amirabadi, Ulrich Reza Kamalian, Numerical investigation of hydrodynamic responses and statistical analysis of imposed forces for various geometries of the crown structure of caisson breakwater, Ocean Engineering, 278; 114358, 2023. doi.org/10.1016/j.oceaneng.2023.114358

67-23   Aisyah Dwi Puspasari, Jyh-Haw Tang, Numerical simulation of scouring around groups of six cylinders with different flow directions, Journal of the Chinese Institute of Engineers, 46.4; 2023. doi.org/10.1080/02533839.2023.2194919

62-23   Rob Nairn, Qimiao Lu, Rebecca Quan, Matthew Hoy, Dain Gillen, Data collection and modeling in support of the Mid-Breton Sediment Diversion Project, Coastal Sediments, 2023. doi.org/10.1142/9789811275135_0246

55-23   Yupeng Ren, Hao Tian, Zhiyuan Chen, Guohui Xu, Lejun Liu, Yibing Li, Two kinds of waves causing the resuspension of deep-sea sediments: excitation and internal solitary waves, Journal of Ocean University of China, 22; pp. 429-440, 2023. doi.org/10.1007/s11802-023-5293-2

42-23   Antonija Harasti, Gordon Gilja, Simulation of equilibrium scour hole development around riprap sloping structure using the numerical model, EGU General Assembly, 2023. doi.org/10.5194/egusphere-egu23-6811

25-23   Ke Hu, Xinglan Bai, Murilo A. Vaz, Numerical simulation on the local scour processing and influencing factors of submarine pipeline, Journal of Marine Science and Engineering, 11.1; 234, 2023. doi.org/10.3390/jmse11010234

12-23   Fan Zhang, Zhipeng Zang, Ming Zhao, Jinfeng Zhang, Numerical investigations on scour and flow around two crossing pipelines on a sandy seabed, Journal of Marine Science and Engineering, 10.12; 2019, 2023. doi.org/10.3390/jmse10122019

10-23 Wenshe Zhou, Yongzhou Cheng, Zhiyuan Lin, Numerical simulation of long-wave wave dissipation in near-water flat-plate array breakwaters, Ocean Engineering, 268; 113377, 2023. doi.org/10.1016/j.oceaneng.2022.113377

181-22   Ramtin Sabeti, Mohammad Heidarzadeh, Numerical simulations of water waves generated by subaerial granular and solid-block landslides: Validation, comparison, and predictive equations, Ocean Engineering, 266.3; 112853, 2022. doi.org/10.1016/j.oceaneng.2022.112853 

167-22 Zhiyong Zhang, Cunhong Pan, Jian Zeng, Fuyuan Chen, Hao Qin, Kun He, Kui Zhu, Enjin Zhao, Hydrodynamics of tidal bore overflow on the spur dike and its infuence on the local scour, Ocean Engineering, 266.4; 113140, 2022. doi.org/10.1016/j.oceaneng.2022.113140

166-22 Nguyet-Minh Nguyen, Duong Do Van, Duy Tu Le, Quyen Nguyen, Bang Tran, Thanh Cong Nguyen, David Wright, Ahad Hasan Tanim, Phong Nguyen Thanh, Duong Tran Anh, Physical and numerical modeling of four different shapes of breakwaters to test the suspended sediment trapping capacity in the Mekong Delta, Estuarine, Coastal and Shelf Science, 279; 108141, 2022. doi.org/10.1016/j.ecss.2022.108141

163-22 Sahameddin Mahmoudi Kurdistani, Giuseppe Roberto Tomasicchio, Felice D’Alessandro, Antonio Francone, Formula for wave transmission at submerged homogeneous porous breakwaters, Ocean Engineering, 266.4; 113053, 2022. doi.org/10.1016/j.oceaneng.2022.113053

162-22 Kai Wei, Xueshuang Yin, Numerical study into configuration of horizontal flanges on hydrodynamic performance of moored box-type floating breakwater, Ocean Engineering, 266.4; 112991, 2022. doi.org/10.1016/j.oceaneng.2022.112991

161-22 Sung-Chul Jang, Jin-Yong Jeong, Seung-Woo Lee, Dongha Kim, Identifying hydraulic characteristics related to fishery activities using numerical analysis and an automatic identification system of a fishing vessel, Journal of Marine Science and Engineering, 10; 1619, 2022. doi.org/10.3390/jmse10111619

156-22 Keith Adams, Mohammad Heidarzadeh, Extratropical cyclone damage to the seawall in Dawlish, UK: Eyewitness accounts, sea level analysis and numerical modelling, Natural Hazards, 2022. doi.org/10.1007/s11069-022-05692-2

155-22 Youxiang Lu, Zhenlu Wang, Zegao Yin, Guoxiang Wu, Bingchen Liang, Experimental and numerical studies on local scour around closely spaced circular piles under the action of steady current, Journal of Marine Science and Engineering, 10; 1569, 2022. doi.org/10.3390/jmse10111569

152-22 Nauman Riyaz Maldar, Ng Cheng Yee, Elif Oguz, Shwetank Krishna, Performance investigation of a drag-based hydrokinetic turbine considering the effect of deflector, flow velocity, and blade shape, Ocean Engineering, 266.2; 112765, 2022. doi.org/10.1016/j.oceaneng.2022.112765

148-22   Ramtin Sabeti, Mohammad Heidarzadeh, Numerical simulations of water waves generated by subaerial granular and solid-block landslides: Validation, comparison, and predictive equations, Ocean Engineering, 266.3; 112853, 2022. doi.org/10.1016/j.oceaneng.2022.112853

145-22   I-Fan Tseng, Chih-Hung Hsu, Po-Hung Yeh, Ting-Chieh Lin, Physical mechanism for seabed scouring around a breakwater—a case study in Mailiao Port, Journal of Marine Science and Engineering, 10; 1386, 2022. doi.org/10.3390/jmse10101386

144-22   Jiarui Yu, Baozeng Yue, Bole Ma, Isogeometric analysis with level set method for large-amplitude liquid sloshing, Ocean Engineering, 265; 112613, 2022. doi.org/10.1016/j.oceaneng.2022.112613

141-22   Qi Yang, Peng Yu, Hongjun Liu, Computational investigation of scour characteristics of USAF in multi-specie sand under steady current, Ocean Engineering, 262; 112141, 2022. doi.org/10.1016/j.oceaneng.2022.112141

128-22   Atish Deoraj, Calvin Wells, Justin Pringle, Derek Stretch, On the reef scale hydrodynamics at Sodwana Bay, South Africa, Environmental Fluid Mechanics, 2022. doi.org/10.1007/s10652-022-09896-9

108-22   Angela Di Leo, Mariano Buccino, Fabio Dentale, Eugenio Pugliese Carratelli, CFD analysis of wind effect on wave overtopping, 32nd International Ocean and Polar Engineering Conference,  ISOPE-I-22-428, 2022.

105-22   Pin-Tzu Su, Chen-shan Kung, Effects of currents and sediment flushing on marine pipes, 32nd International Ocean and Polar Engineering Conference, ISOPE-I-22-153, 2022.

89-22   Kai Wei, Cong Zhou, Bo Xu, Spatial distribution models of horizontal and vertical wave impact pressure on the elevated box structure, Applied Ocean Research, 125; 103245, 2022. doi.org/10.1016/j.apor.2022.103245

87-22   Tran Thuy Linh, Numerical modelling (3D) of wave interaction with porous structures in the Mekong Delta coastal zone, Thesis, Ho Chi Minh City University of Technology, 2022.

82-22   Seyyed-Mahmood Ghassemizadeh, Mohammad Javad Ketabdari, Modeling of solitary wave interaction with curved-facing seawalls using numerical method, Advances in Civil Engineering, 5649637, 2022. doi.org/10.1155/2022/5649637

81-22   Raphael Alwan, Boyin Ding, David M. Skene, Zhaobin Li, Luke G. Bennetts, On the structure of waves radiated by a submerged cylinder undergoing large-amplitude heave motions, 32nd International Ocean and Polar Engineering Conference, Shanghai, China, June 5-10, 2022. doi.org/10.1111/jfr3.12828

77-22   Weiyun Chen, Linchong Huang, Dan Wang, Chao Liu, Lingyu Xu, Zhi Ding, Effects of siltation and desiltation on the wave-induced stability of foundation trench of immersed tunnel, Soil Dynamics and Earthquake Engineering, 160; 107360, 2022. doi.org/10.1016/j.soildyn.2022.107360

63-22   Yongzhou Cheng, Zhiyuan Lin, Gan Hu, Xing Lyu, Numerical simulation of the hydrodynamic characteristics of the porous I-type composite breakwater, Journal of Marine Science and Application, 21; pp. 140-150, 2022. doi.org/10.1007/s11804-022-00251-4

37-22   Ray-Yeng Yang, Chuan-Wen Wang, Chin-Cheng Huang, Cheng-Hsien Chung, Chung-Pang, Chen, Chih-Jung Huang, The 1:20 scaled hydraulic model test and field experiment of barge-type floating offshore wind turbine system, Ocean Engineering, 247.1; 110486, 2022. doi.org/10.1016/j.oceaneng.2021.110486

35-22   Mingchao Cui, Zhisong Li, Chenglin Zhang, Xiaoyu Guo, Statistical investigation into the flow field of closed aquaculture tanks aboard a platform under periodic oscillation, Ocean Engineering, 248; 110677, 2022. doi.org/10.1016/j.oceaneng.2022.110677

30-22   Jijian Lian, Jiale Li, Yaohua Guo, Haijun Wang, Xu Yang, Numerical study on local scour characteristics of multi-bucket jacket foundation considering exposed height, Applied Ocean Research, 121; 103092. doi.org/10.1016/j.apor.2022.103092

19-22   J.J. Wiegerink, T.E. Baldock, D.P. Callaghan, C.M. Wang, Slosh suppression blocks – A concept for mitigating fluid motions in floating closed containment fish pen in high energy environments, Applied Ocean Research, 120; 103068, 2022. doi.org/10.1016/j.apor.2022.103068

9-22   Amir Bordbar, Soroosh Sharifi, Hassan Hemida, Investigation of scour around two side-by-side piles with different spacing ratios in live-bed, Lecture Notes in Civil Engineering, 208; pp. 302-309, 2022. doi.org/10.1007/978-981-16-7735-9_33

7-22   Jinzhao Li, Xuan Kong, Yilin Yang, Lu Deng, Wen Xiong, CFD investigations of tsunami-induced scour around bridge piers, Ocean Engineering, 244; 110373, 2022. doi.org/10.1016/j.oceaneng.2021.110373

3-22   Ana Gomes, José Pinho, Wave loads assessment on coastal structures at inundation risk using CFD modelling, Climate Change and Water Security, 178; pp. 207-218, 2022. doi.org/10.1007/978-981-16-5501-2_17

2-22   Ramtin Sabeti, Mohammad Heidarzadeh, Numerical simulations of tsunami wave generation by submarine landslides: Validation and sensitivity analysis to landslide parameters, Journal of Waterway, Port, Coastal, and Ocean Engineering, 148.2; 05021016, 2022. doi.org/10.1061/(ASCE)WW.1943-5460.0000694

146-21   Ming-ming Liu, Hao-cheng Wang, Guo-qiang Tang, Fei-fei Shao, Xin Jin, Investigation of local scour around two vertical piles by using numerical method, Ocean Engineering, 244; 110405, 2021. doi.org/10.1016/j.oceaneng.2021.110405

135-21   Jian Guo, Jiyi Wu, Tao Wang, Prediction of local scour depth of sea-crossing bridges based on the energy balance theory, Ships and Offshore Structures, 16.10, 2021. doi.org/10.1080/17445302.2021.2005362

133-21   Sahel Sohrabi, Mohamad Ali Lofollahi Yaghin, Mohamad Hosein Aminfar, Alireza Mojtahedi, Experimental and numerical investigation of hydrodynamic performance of a sloping floating breakwater with and without chain-net, Iranian Journal of Science and Technology: Transactions of Civil Engineering, , 2021. doi.org/10.1007/s40996-021-00780-y

131-21   Seyed Morteza Marashian, Mehdi Adjami, Ahmad Rezaee Mazyak, Numerical modelling investigation of wave interaction on composite berm breakwater, China Ocean Engineering, 35; pp. 631-645, 2021. doi.org/10.1007/s13344-021-0060-x

124-21   Ramin Safari Ghaleh, Omid Aminoroayaie Yamini, S. Hooman Mousavi, Mohammad Reza Kavianpour, Numerical modeling of failure mechanisms in articulated concrete block mattress as a sustainable coastal protection structure, Sustainability, 13.22; pp. 1-19, 2021.

118-21   A. Keshavarz, M. Vaghefi, G. Ahmadi, Investigation of flow patterns around rectangular and oblong peirs with collar located in a 180-degree sharp bend, Scientia Iranica A, 28.5; pp. 2479-2492, 2021.

109-21   Jacek Jachowski, Edyta Książkiewicz, Izabela Szwoch, Determination of the aerodynamic drag of pneumatic life rafts as a factor for increasing the reliability of rescue operations, Polish Maritime Research, 28.3; p. 128-136, 2021. doi.org/10.2478/pomr-2021-0040

107-21   Jiay Han, Bing Zhu, Baojie Lu, Hao Ding, Ke Li, Liang Cheng, Bo Huang, The influence of incident angles and length-diameter ratios on the round-ended cylinder under regular wave action, Ocean Engineering, 240; 109980, 2021. doi.org/10.1016/j.oceaneng.2021.109980

96-21   Andrea Franco, Jasper Moernaut, Barbara Schneider-Muntau, Michael Strasser, Bernhard Gems, Triggers and consequences of landslide-induced impulse waves – 3D dynamic reconstruction of the Taan Fiord 2015 tsunami event, Engineering Geology, 294; 106384, 2021. doi.org/10.1016/j.enggeo.2021.106384

95-21   Ahmed A. Romya, Hossam M. Moghazy, M.M. Iskander, Ahmed M. Abdelrazek, Performance assessment of corrugated semi-circular breakwaters for coastal protection, Alexandria Engineering Journal, in press, 2021. doi.org/10.1016/j.aej.2021.08.086

87-21   Ruigeng Hu, Hongjun Liu, Hao Leng, Peng Yu, Xiuhai Wang, Scour characteristics and equilibrium scour depth prediction around umbrella suction anchor foundation under random waves, Journal of Marine Science and Engineering, 9; 886, 2021. doi.org/10.3390/jmse9080886

78-21   Sahir Asrari, Habib Hakimzadeh, Nazila Kardan, Investigation on the local scour beneath piggyback pipelines under clear-water conditions, China Ocean Engineering, 35; pp. 422-431, 2021. doi.org/10.1007/s13344-021-0039-7

64-21   Pin-Tzu Su, Chen-shan Kung, Effects of diffusers on discharging jet, 31st International Ocean and Polar Engineering Conference (ISOPE), Rhodes, Greece, June 20-25, 2021.

62-21   Fei Wu, Wei Li, Shuzhao Li, Xiaopeng Shen, Delong Dong, Numerical simulation of scour of backfill soil by jetting flows on the top of buried caisson, 31st International Ocean and Polar Engineering Conference (ISOPE), Rhodes, Greece, June 20-25, 2021.

56-21   Murat Aksel, Oral Yagci, V.S. Ozgur Kirca, Eryilmaz Erdog, Naghmeh Heidari, A comparitive analysis of coherent structures around a pile over rigid-bed and scoured-bottom, Ocean Engineering, 226; 108759, 2021. doi.org/10.1016/j.oceaneng.2021.108759

52-21   Byeong Wook Lee, Changhoon Lee, Equation for ship wave crests in a uniform current in the entire range of water depths, Coastal Engineering, 167; 103900, 2021. doi.org/10.1016/j.coastaleng.2021.103900

43-21   Agnieszka Faulkner, Claire E. Bulgin, Christopher J. Merchant, Characterising industrial thermal plumes in coastal regions using 3-D numerical simulations, Environmental Research Communications, 3; 045003, 2021. doi.org/10.1088/2515-7620/abf62e

39-21   Fan Yang, Yiqi Zhang, Chao Liu, Tieli Wang, Dongin Jiang, Yan Jin, Numerical and experimental investigations of flow pattern and anti-vortex measures of forebay in a multi-unit pumping station, Water, 13.7; 935, 2021. doi.org/10.3390/w13070935

30-21   Norfadhlina Khalid, Aqil Azraie Che Shamshudin, Megat Khalid Puteri Zarina, Analysis on wave generation and hull: Modification for fishing vessels, Advanced Engineering for Processes and Technologies II: Advanced Structured Materials, 147; pp. 77-89, 2021. doi.org/10.1007/978-3-030-67307-9_9

28-21   Jae-Sang Jung, Jae-Seon Yoon, Seokkoo Kang, Seokil Jeong, Seung Oh Lee, Yong-Sung Park, Discharge characteristics of drainage gates on Saemangeum tidal dyke, South Korea, KSCE Journal of Engineering, 25; pp. 1308-1325, 2021. doi.org/10.1007/s12205-021-0590-z

24-21   Ali Temel, Mustafa Dogan, Time dependent investigation of the wave induced scour at the trunk section of a rubble mound breakwater, Ocean Engineering, 221; 108564, 2021. doi.org/10.1016/j.oceaneng.2020.108564

13-21   P.X. Zou, L.Z. Chen, The coupled tube-mooring system SFT hydrodynamic characteristics under wave excitations, Proceedings, 14th International Conference on Vibration Problems, Crete, Greece, September 1 – 4, 2019, pp. 907-923, 2021. doi.org/10.1007/978-981-15-8049-9_55

122-20  M.A. Musa, M.F. Roslan, M.F. Ahmad, A.M. Muzathik, M.A. Mustapa, A. Fitriadhy, M.H. Mohd, M.A.A. Rahman, The influence of ramp shape parameters on performance of overtopping breakwater for energy conversion, Journal of Marine Science and Engineering, 8.11; 875, 2020. doi.org/10.3390/jmse8110875

120-20  Lee Hooi Chie, Ahmad Khairi Abd Wahab, Derivation of engineering design criteria for flow field around intake structure: A numerical simulation study, Journal of Marine Science and Engineering, 8.10; 827, 2020.  doi.org/10.3390/jmse8100827

109-20  Mario Maiolo, Riccardo Alvise Mel, Salvatore Sinopoli, A stepwise approach to beach restoration at Calabaia Beach, Water, 12.10; 2677, 2020. doi.org/10.3390/w12102677

107-20  S. Deshpande, P. Sundsbø, S. Das, Ship resistance analysis using CFD simulations in Flow-3D, International Journal of Multiphysics, 14.3; pp. 227-236, 2020. doi.org/10.21152/1750-9548.14.3.227

103-20   Mahmood Nematollahi, Mohammad Navim Moghid, Numerical simulation of spatial distribution of wave overtopping on non-reshaping berm breakwaters, Journal of Marine Science and Application, 19; pp. 301-316, 2020. doi.org/10.1007/s11804-020-00147-1

98-20   Lin Zhao, Ning Wang, Qian Li, Analysis of flow characteristics and wave dissipation performances of a new structure, Proceedings, 30th International Ocean and Polar Engineering Conference (ISOPE), Online, October 11-16, ISOPE-I-20-3289, 2020.

96-20   Xiaoyu Guo, Zhisong Li, Mingchao Cui, Benlong Wang, Numerical investigation on flow characteristics of water in the fish tank on a force-rolling aquaculture platform, Ocean Engineering, 217; 107936, 2020. doi.org/10.1016/j.oceaneng.2020.107936

92-20   Yong-Jun Cho, Scour controlling effect of hybrid mono-pile as a substructure of offshore wind turbine: A numerical study, Journal of Marine Science and Engineering, 8.9; 637, 2020. doi.org/10.3390/jmse8090637

89-20   Andrea Franco, Jasper Moernaut, Barbara Schneider-Muntau, Michael Strasser, Bernhard Gems, The
1958 Lituya Bay tsunami – pre-event bathymetry reconstruction and 3D numerical modelling utilising the computational fluid dynamics software
Flow-3D
, Natural Hazards and Earth Systems Sciences, 20; pp. 2255–2279, 2020. doi.org/10.5194/nhess-20-2255-2020

81-20   Eliseo Marchesi, Marco Negri, Stefano Malavasi, Development and analysis of a numerical model for a two-oscillating-body wave energy converter in shallow water, Ocean Engineering, 214; 107765, 2020. doi.org/10.1016/j.oceaneng.2020.107765

79-20   Zegao Yin, Yanxu Wang, Yong Liu, Wei Zou, Wave attenuation by rigid emergent vegetation under combined wave and current flows, Ocean Engineering, 213; 107632, 2020. doi.org/10.1016/j.oceaneng.2020.107632

71-20   B. Pan, N. Belyaev, FLOW-3D software for substantiation the layout of the port water area, IOP Conference Series: Materials Science and Engineering, Construction Mechanics, Hydraulics and Water Resources Engineering (CONMECHYDRO), Tashkent, Uzbekistan, 23-25 April, 883; 012020, 2020. doi.org/10.1088/1757-899X/883/1/012020

51-20       Yupeng Ren, Xingbei Xu, Guohui Xu, Zhiqin Liu, Measurement and calculation of particle trajectory of liquefied soil under wave action, Applied Ocean Research, 101; 102202, 2020. doi.org/10.1016/j.apor.2020.102202

50-20       C.C. Battiston, F.A. Bombardelli, E.B.C. Schettini, M.G. Marques, Mean flow and turbulence statistics through a sluice gate in a navigation lock system: A numerical study, European Journal of Mechanics – B/Fluids, 84; pp.155-163, 2020. doi.org/10.1016/j.euromechflu.2020.06.003

49-20     Ahmad Fitriadhy, Nur Amira Adam, Nurul Aqilah Mansor, Mohammad Fadhli Ahmad, Ahmad Jusoh, Noraieni Hj. Mokhtar, Mohd Sofiyan Sulaiman, CFD investigation into the effect of heave plate on vertical motion responses of a floating jetty, CFD Letters, 12.5; pp. 24-35, 2020. doi.org/10.37934/cfdl.12.5.2435

40-20       P. April Le Quéré, I. Nistor, A. Mohammadian, Numerical modeling of tsunami-induced scouring around a square column: Performance assessment of FLOW-3D and Delft3D, Journal of Coastal Research (preprint), 2020. doi.org/10.2112/JCOASTRES-D-19-00181

38-20       Sahameddin Mahmoudi Kurdistani, Giuseppe Roberto Tomasicchio, Daniele Conte, Stefano Mascetti, Sensitivity analysis of existing exponential empirical formulas for pore pressure distribution inside breakwater core using numerical modeling, Italian Journal of Engineering Geology and Environment, 1; pp. 65-71, 2020. doi.org/10.4408/IJEGE.2020-01.S-08

36-20       Mohammadamin Torabi, Bruce Savage, Efficiency improvement of a novel submerged oscillating water column (SOWC) energy harvester, Proceedings, World Environmental and Water Resources Congress (Cancelled), Henderson, Nevada, May 17–21, 2020. doi.org/10.1061/9780784482940.003

32-20       Adriano Henrique Tognato, Modelagem CFD da interação entre hidrodinâmica costeira e quebra-mar submerso: estudo de caso da Ponta da Praia em Santos, SP (CFD modeling of interaction between sea waves and submerged breakwater at Ponta de Praia – Santos, SP: a case study, Thesis, Universidad Estadual de Campinas, Campinas, Brazil, 2020.

29-20   Ana Gomes, José L. S. Pinho, Tiago Valente, José S. Antunes do Carmo and Arkal V. Hegde, Performance assessment of a semi-circular breakwater through CFD modelling, Journal of Marine Science and Engineering, 8.3, art. no. 226, 2020. doi.org/10.3390/jmse8030226

23-20  Qi Yang, Peng Yu, Yifan Liu, Hongjun Liu, Peng Zhang and Quandi Wang, Scour characteristics of an offshore umbrella suction anchor foundation under the combined actions of waves and currents, Ocean Engineering, 202, art. no. 106701, 2020. doi.org/10.1016/j.oceaneng.2019.106701

04-20  Bingchen Liang, Shengtao Du, Xinying Pan and Libang Zhang, Local scour for vertical piles in steady currents: review of mechanisms, influencing factors and empirical equations, Journal of Marine Science and Engineering, 8.1, art. no. 4, 2020. doi.org/10.3390/jmse8010004

104-19   A. Fitriadhy, S.F. Abdullah, M. Hairil, M.F. Ahmad and A. Jusoh, Optimized modelling on lateral separation of twin pontoon-net floating breakwater, Journal of Mechanical Engineering and Sciences, 13.4, pp. 5764-5779, 2019. doi.org/10.15282/jmes.13.4.2019.04.0460

103-19  Ahmad Fitriadhy, Nurul Aqilah Mansor, Nur Adlina Aldin and Adi Maimun, CFD analysis on course stability of an asymmetrical bridle towline model of a towed ship, CFD Letters, 11.12, pp. 43-52, 2019.

90-19   Eric P. Lemont and Karthik Ramaswamy, Computational fluid dynamics in coastal engineering: Verification of a breakwater design in the Torres Strait, Proceedings, pp. 762-768, Australian Coasts and Ports 2019 Conference, Hobart, Australia, September 10-13, 2019.

86-19   Mohammed Arab Fatiha, Benoît Augier, François Deniset, Pascal Casari, and Jacques André Astolfi, Morphing hydrofoil model driven by compliant composite structure and internal pressure, Journal of Marine Science and Engineering, 7:423, 2019. doi.org/10.3390/jmse7120423

83-19   Cong-Uy Nguyen, So-Young Lee, Thanh-Canh Huynh, Heon-Tae Kim, and Jeong-Tae Kim, Vibration characteristics of offshore wind turbine tower with gravity-based foundation under wave excitation, Smart Structures and Systems, 23:5, pp. 405-420, 2019. doi.org/10.12989/sss.2019.23.5.405

68-19   B.W. Lee and C. Lee, Development of an equation for ship wave crests in a current in whole water depths, Proceedings, 10th International Conference on Asian and Pacific Coasts (APAC 2019), Hanoi, Vietnam, September 25-28, 2019; pp. 207-212, 2019. doi.org/10.1007/978-981-15-0291-0_29

62-19   Byeong Wook Lee and Changhoon Lee, Equation for ship wave crests in the entire range of water depths, Coastal Engineering, 153:103542, 2019. doi.org/10.1016/j.coastaleng.2019.103542

23-19     Mariano Buccino, Mohammad Daliri, Fabio Dentale, Angela Di Leo, and Mario Calabrese, CFD experiments on a low crested sloping top caisson breakwater, Part 1: Nature of loadings and global stability, Ocean Engineering, Vol. 182, pp. 259-282, 2019. doi.org/10.1016/j.oceaneng.2019.04.017

21-19     Mahsa Ghazian Arabi, Deniz Velioglu Sogut, Ali Khosronejad, Ahmet C. Yalciner, and Ali Farhadzadeh, A numerical and experimental study of local hydrodynamics due to interactions between a solitary wave and an impervious structure, Coastal Engineering, Vol. 147, pp. 43-62, 2019. doi.org/10.1016/j.coastaleng.2019.02.004

15-19     Chencong Liao, Jinjian Chen, and Yizhou Zhang, Accumulation of pore water pressure in a homogeneous sandy seabed around a rocking mono-pile subjected to wave loads, Vol. 173, pp. 810-822, 2019. doi.org/10.1016/j.oceaneng.2018.12.072

09-19     Yaoyong Chen, Guoxu Niu, and Yuliang Ma, Study on hydrodynamics of a new comb-type floating breakwater fixed on the water surface, 2018 International Symposium on Architecture Research Frontiers and Ecological Environment (ARFEE 2018), Wuhan, China, December 14-16, 2018, E3S Web of Conferences Vol. 79, Art. No. 02003, 2019. doi.org/10.1051/e3sconf/20197902003

08-19     Hongda Shi, Zhi Han, and Chenyu Zhao, Numerical study on the optimization design of the conical bottom heaving buoy convertor, Ocean Engineering, Vol. 173, pp. 235-243, 2019. doi.org/10.1016/j.oceaneng.2018.12.061

06-19   S. Hemavathi, R. Manjula and N. Ponmani, Numerical modelling and experimental investigation on the effect of wave attenuation due to coastal vegetation, Proceedings of the Fourth International Conference in Ocean Engineering (ICOE2018), Vol. 2, pp. 99-110, 2019. doi.org/10.1007/978-981-13-3134-3_9

87-18   Muhammad Syazwan Bazli, Omar Yaakob and Kang Hooi Siang, Validation study of u-oscillating water column device using computational fluid dynamic (CFD) simulation, 11thInternational Conference on Marine Technology, Kuala Lumpur, Malaysia, August 13-14, 2018.

86-18   Nur Adlina Aldin, Ahmad Fitriadhy, Nurul Aqilah Mansor, and Adi Maimun, CFD analysis on unsteady yaw motion characteristic of a towed ship, 11th International Conference on Marine Technology, Kuala Lumpur, Malaysia, August 13-14, 2018.

78-18 A.A. Abo Zaid, W.E. Mahmod, A.S. Koraim, E.M. Heikal and H.E. Fath, Wave interaction of partially immersed semicircular breakwater suspended on piles using FLOW-3D, CSME Conference Proceedings, Toronto, Canada, May 27-30, 2018.

73-18   Jian Zhou and Subhas K. Venayagamoorthy, Near-field mean flow dynamics of a cylindrical canopy patch suspended in deep water, Journal of Fluid Mechanics, Vol. 858, pp. 634-655, 2018. doi.org/10.1017/jfm.2018.775

69-18   Keisuke Yoshida, Shiro Maeno, Tomihiro Iiboshi and Daisuke Araki, Estimation of hydrodynamic forces acting on concrete blocks of toe protection works for coastal dikes by tsunami overflows, Applied Ocean Research, Vol. 80, pp. 181-196, 2018. doi.org/10.1016/j.apor.2018.09.001

68-18   Zegao Yin, Yanxu Wang and Xiaoyu Yang, Regular wave run-up attenuation on a slope by emergent rigid vegetation, Journal of Coastal Research (in-press), 2018. doi.org/10.2112/JCOASTRES-D-17-00200.1

65-18   Dagui Tong, Chencong Liao, Jinjian Chen and Qi Zhang, Numerical simulation of a sandy seabed response to water surface waves propagating on current, Journal of Marine Science and Engineering, Vol. 6, No. 3, 2018. doi.org/10.3390/jmse6030088

61-18   Manuel Gerardo Verduzco-Zapata, Aramis Olivos-Ortiz, Marco Liñán-Cabello, Christian Ortega-Ortiz, Marco Galicia-Pérez, Chris Matthews, and Omar Cervantes-Rosas, Development of a Desalination System Driven by Low Energy Ocean Surface Waves, Journal of Coastal Research: Special Issue 85 – Proceedings of the 15th International Coastal Symposium, pp. 1321 – 1325, 2018. doi.org/10.2112/SI85-265.1

37-18   Songsen Xu, Chunshuo Jiao, Meng Ning and Sheng Dong, Analysis of Buoyancy Module Auxiliary Installation Technology Based on Numerical Simulation, Journal of Ocean University of China, vol. 17, no. 2, pp. 267-280, 2018. doi.org/10.1007/s11802-018-3305-4

36-18   Deniz Velioglu Sogut and Ahmet Cevdet Yalciner, Performance comparison of NAMI DANCE and FLOW-3D® models in tsunami propagation, inundation and currents using NTHMP benchmark problems, Pure and Applied Geophysics, pp. 1-39, 2018. doi.org/10.1007/s00024-018-1907-9

26-18   Mohammad Sarfaraz and Ali Pak, Numerical investigation of the stability of armour units in low-crested breakwaters using combined SPH–Polyhedral DEM method, Journal of Fluids and Structures, vol. 81, pp. 14-35, 2018. doi.org/10.1016/j.jfluidstructs.2018.04.016

25-18   Yen-Lung Chen and Shih-Chun Hsiao, Numerical modeling of a buoyant round jet under regular waves, Ocean Engineering, vol. 161, pp. 154-167, 2018. doi.org/10.1016/j.oceaneng.2018.04.093

13-18   Yizhou Zhang, Chencong Liao, Jinjian Chen, Dagui Tong, and Jianhua Wang, Numerical analysis of interaction between seabed and mono-pile subjected to dynamic wave loadings considering the pile rocking effect, Ocean Engineering, Volume 155, 1 May 2018, Pages 173-188, doi.org/10.1016/j.oceaneng.2018.02.041

11-18  Ching-Piao Tsai, Chun-Han Ko and Ying-Chi Chen, Investigation on Performance of a Modified Breakwater-Integrated OWC Wave Energy Converter, Open Access Sustainability 2018, 10(3), 643; doi:10.3390/su10030643, © Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2018.

58-17   Jian Zhou, Claudia Cenedese, Tim Williams and Megan Ball, On the propagation of gravity currents over and through a submerged array of circular cylinders, Journal of Fluid Mechanics, Vol. 831, pp. 394-417, 2017. doi.org/10.1017/jfm.2017.604

56-17   Yu-Shu Kuo, Chih-Yin Chung, Shih-Chun Hsiao and Yu-Kai Wang, Hydrodynamic characteristics of Oscillating Water Column caisson breakwaters, Renewable Energy, vol. 103, pp. 439-447, 2017. doi.org/10.1016/j.renene.2016.11.028

47-17   Jae-Nam Cho, Chang-Geun Song, Kyu-Nam Hwang and Seung-Oh Lee, Experimental assessment of suspended sediment concentration changed by solitary wave, Journal of Marine Science and Technology, Vol. 25, No. 6, pp. 649-655 (2017) 649 DOI: 10.6119/JMST-017-1226-04

45-17   Muhammad Aldhiansyah Rifqi Fauzi, Haryo Dwito Armono, Mahmud Mustain and Aniendhita Rizki Amalia, Comparison Study of Various Type Artificial Reef Performance in Reducing Wave Height, Regional Conference in Civil Engineering (RCCE) 430 The Third International Conference on Civil Engineering Research (ICCER) August 1st-2nd 2017, Surabaya – Indonesia.

44-17   Fabio Dentale, Ferdinando Reale, Angela Di Leo, and Eugenio Pugliese Carratelli, A CFD approach to rubble mound breakwater design, International Journal of Naval Architecture and Ocean Engineering, Available online 30 December 2017.

39-17   Milad Rashidinasab and Mehdi Behdarvandi Askar, Modeling the Pressure Distribution and the Changes of Water Level around the Offshore Platforms Exposed to Waves, Using the Numerical Model of FLOW-3D, Computational Water, Energy, and Environmental Engineering, 2017, 6, 97-106, http://www.scirp.org/journal/cweee, ISSN Online: 2168-1570, ISSN Print: 2168-1562

30-17   Omid Nourani and Mehdi Behdarvandi Askar, Comparison of the Effect of Tetrapod Block and Armor X block on Reducing Wave Overtopping in Breakwaters, Open Journal of Marine Science, 2017, 7, 472-484 http://www.scirp.org/journal/ojms ISSN Online: 2161-7392.

29-17   J.A. Vasquez, Modelling the generation and propagation of landslide generated waves, Leadership in Sustainable Infrastructure, Annual Conference – Vancouver, May 31 – June 3, 2017

28-17   Manuel G. Verduzco-Zapata, Francisco J. Ocampo-Torres, Chris Matthews, Aramis Olivos-Ortiz, Diego E. and Galván-Pozos, Development of a Wave Powered Desalination Device Numerical Modelling, Proceedings of the 12th European Wave and Tidal Energy Conference 27th Aug -1st Sept 2017, Cork, Ireland

20-17   Chu-Kuan Lin, Jaw-Guei Lin, Ya-Lan Chen, Chin-Shen Chang, Seabed Change and Soil Resistance Assessment of Jack up Foundation, Proceedings of the Twenty-seventh (2017) International Ocean and Polar Engineering Conference, San Francisco, CA, USA, June 25-30, 2017, Copyright © 2017 by the International Society of Offshore and Polar Engineers (ISOPE), ISBN 978-1-880653-97-5; ISSN 1098-6189.

19-17   Velioğlu Deniz, Advanced Two- and Three-Dimensional Tsunami – Models Benchmarking and Validation, Ph.D Thesis:, Middle East Technical University, June 2017

18-17   Farrokh Mahnamfar and Abdüsselam Altunkaynak, Comparison of numerical and experimental analyses for optimizing the geometry of OWC systems, Ocean Engineering 130 (2017) 10–24.

07-17   Jonas Čerka, Rima Mickevičienė, Žydrūnas Ašmontas, Lukas Norkevičius, Tomas Žapnickas, Vasilij Djačkov and Peilin Zhou, Optimization of the research vessel hull form by using numerical simulation, Ocean Engineering 139 (2017) 33–38

05-17   Liang, B.; Ma, S.; Pan, X., and Lee, D.Y., Numerical modelling of wave run-up with interaction between wave and dolosse breakwater, In: Lee, J.L.; Griffiths, T.; Lotan, A.; Suh, K.-S., and Lee, J. (eds.), 2017, The 2nd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 79, pp. 294-298. Coconut Creek (Florida), ISSN 0749-0208.

02-17   A. Yazid Maliki, M. Azlan Musa, Ahmad M.F., Zamri I., Omar Y., Comparison of numerical and experimental results for overtopping discharge of the OBREC wave energy converter, Journal of Engineering Science and Technology, In Press, © School of Engineering, Taylor’s University

01-17   Tanvir Sayeed, Bruce Colbourne, David Molyneux, Ayhan Akinturk, Experimental and numerical investigation of wave forces on partially submerged bodies in close proximity to a fixed structure, Ocean Engineering, Volume 132, Pages 70–91, March 2017

101-16 Xin Li, Liang-yu Xu, Jian-Min Yang, Study of fluid resonance between two side-by-side floating barges, Journal of Hydrodynamics, vol. B-28, no. 5, pp. 767-777, 2016. doi.org/10.1016/S1001-6058(16)60679-0

81-16   Loretta Gnavi, Deep water challenges: development of depositional models to support geohazard assessment for submarine facilities, Ph.D. Thesis: Politecnico di Torino, May 2016

80-16   Mohammed Ibrahim, Hany Ahmed, Mostafa Abd Alall and A.S. Koraim, Proposing and investigating the efficiency of vertical perforated breakwater, International Journal of Scientific & Engineering Research, Volume 7, Issue 3, March 2016, ISSN 2229-5518

72-16   Yen-Lung Chen and Shih-Chun Hsiao, Generation of 3D water waves using mass source wavemaker applied to Navier–Stokes model, Coastal Engineering 109 (2016) 76–95.

64-16   Jae Nam Cho, Dong Hyun Kim and Seung Oh Lee, Experimental Study of Shape and Pressure Characteristics of Solitary Wave generated by Sluice Gate for Various Conditions, Journal of the Korean Society of Safety, Vol. 31, No. 2, pp. 70-75, April 2016, Copyright @ 2016 by The Korean Society of Safety (pISSN 1738-3803, eISSN 2383-9953) All right reserved. http://dx.doi.org/10.14346/JKOSOS.2016.31.2.70

56-16   Ali A. Babajani, Mohammad Jafari and Parinaz Hafezi Sefat, Numerical investigation of distance effect between two Searasers for hydrodynamic performance, Alexandria Engineering Journal, June 2016.

53-16   Hwang-Ki Lee, Byeong-Kuk Kim, Jongkyu Kim and Hyeon-Ju Kim, OTEC thermal dispersion in coastal waters of Tarawa, Kiribati, OCEANS 2016 – Shanghai, April 2016, 10.1109/OCEANSAP.2016.7485548, © IEEE.

50-16   Mohsin A. R. Irkal, S. Nallayarasu and S. K. Bhattacharyya, CFD simulation of roll damping characteristics of a ship midsection with bilge keel, Proceedings of the ASME 2016 35th International Conference on Ocean, Offshore and Arctic Engineering, OMAE2016, June 19-24, 2016, Busan, South Korea

49-16   Bill Baird, Seth Logan, Wim Van Der Molen, Trevor Elliot and Don Zimmer, Thoughts on the future of physical models in coastal engineering, Proceedings of the 6th International Conference on the Application of Physical Modelling in Coastal and Port Engineering and Science (Coastlab16) Ottawa, Canada, May 10-13, 2016 Copyright ©: Creative Commons CC BY-NC-ND 4.0

47-16   KH Kim et. al, Numerical analysis on the effects of shoal on the ship wave, Applied Engineering, Materials and Mechanics: Proceedings of the 2016 International Conference on Applied Engineering, Materials and Mechanics (ICAEMM 2016)

17-16  Nan-Jing Wu, Shih-Chun Hsiao, Hsin-Hung Chen, and Ray-Yeng Yang, The study on solitary waves generated by a piston-type wave maker, Ocean Engineering, 117(2016)114–129

13-16   Maryam Deilami-Tarifi, Mehdi Behdarvandi-Askar, Vahid Chegini, and Sadegh Haghighi-Pou, Modeling of the Changes in Flow Velocity on Seawalls under Different Conditions Using FLOW-3DSoftware, Open Journal of Marine Science, 2016, 6, 317-322, Published Online April 2016 in SciRes.

01-16   Mohsin A.R. Irkal, S. Nallayarasu, and S.K. Bhattacharyya, CFD approach to roll damping of ship with bilge keel with experimental validation, Applied Ocean Research, Volume 55, February 2016, Pages 1–17

121-15   Josh Carter, Scott Fenical, Craig Hunter and Joshua Todd, CFD modeling for the analysis of living shoreline structure performance, Coastal Structures and Solutions to Coastal Disasters Joint Conference, Boston, MA, Sept. 9-11, 2015. © 2017 by the American Society of Civil Engineers. doi.org/10.1061/9780784480304.047

114-15   Jisheng Zhang, Peng Gao, Jinhai Zheng, Xiuguang Wu, Yuxuan Peng and Tiantian Zhang, Current-induced seabed scour around a pile-supported horizontal-axis tidal stream turbine, Journal of Marine Science and Technology, Vol. 23, No. 6, pp. 929-936 (2015) 929, DOI: 10.6119/JMST-015-0610-11

108-15  Tiecheng Wang, Tao Meng, and Hailong Zha, Analysis of Tsunami Effect and Structural Response, ISSN 1330-3651 (Print), ISSN 1848-6339 (Online), DOI: 10.17559/TV-20150122115308

107-15   Jie Chen, Changbo Jiang, Wu Yang, Guizhen Xiao, Laboratory study on protection of tsunami-induced scour by offshore breakwaters, Natural Hazards, 2015, 1-19

85-15   Majid A. Bhinder, M.T. Rahmati, C.G. Mingham and G.A. Aggidis, Numerical hydrodynamic modelling of a pitching wave energy converter, European Journal of Computational Mechanics, Volume 24, Issue 4, 2015, DOI: 10.1080/17797179.2015.1096228

65-15   Giancarlo Alfonsi, Numerical Simulations of Wave-Induced Flow Fields around Large-Diameter Surface-Piercing Vertical Circular CylinderComputation 20153(3), 386-426; doi:10.3390/computation3030386

61-15   Bingchen Liang, Duo Li, Xinying Pan and Guangxin Jiang, Numerical Study of Local Scour of Pipeline under Combined Wave and Current Conditions, Proceedings of the Twenty-fifth (2015) International Ocean and Polar Engineering Conference Kona, Big Island, Hawaii, USA, June 21-26, 2015 Copyright © 2015 by the International Society of Offshore and Polar Engineers (ISOPE) ISBN 978-1-880653-89-0; ISSN 1098-6189.

60-15   Chun-Han Ko, Ching-Piao Tsai, Ying-Chi Chen, and Tri-Octaviani Sihombing, Numerical Simulations of Wave and Flow Variations between Submerged Breakwaters and Slope Seawall, Proceedings of the Twenty-fifth (2015) International Ocean and Polar Engineering Conference Kona, Big Island, Hawaii, USA, June 21-26, 2015 Copyright © 2015 by the International Society of Offshore and Polar Engineers (ISOPE) ISBN 978-1-880653-89-0; ISSN 1098-6189.

57-15   Giacomo Viccione and Settimio Ferlisi, A numerical investigation of the interaction between debris flows and defense barriers, Advances in Environmental and Geological Science and Engineering, ISBN: 978-1-61804-314-6, 2015

56-15   Vittorio Bovolin, Eugenio Pugliese Carratelli and Giacomo Viccione, A numerical study of liquid impact on inclined surfaces, Advances in Environmental and Geological Science and Engineering, ISBN: 978-1-61804-314-6, 2015

49-15   Fabio Dentale, Giovanna Donnarumma, Eugenio Pugliese Carratelli, and Ferdinando Reale, A numerical method to analyze the interaction between sea waves and rubble mound emerged breakwaters, WSEAS TRANSACTIONS on FLUID MECHANICS, E-ISSN: 2224-347X, Volume 10, 2015

45-15   Diego Vicinanza, Daniela Salerno, Fabio Dentale and Mariano Buccino, Structural Response of Seawave Slot-cone Generator (SSG) from Random Wave CFD Simulations, Proceedings of the Twenty-fifth (2015) International Ocean and Polar Engineering Conference, Kona, Big Island, Hawaii, USA, June 21-26, 2015, Copyright © 2015 by the International Society of Offshore and Polar Engineers (ISOPE), ISBN 978-1-880653-89-0; ISSN 1098-6189

38-15   Yen-Lung Chen, Shih-Chun Hsiao, Yu-Cheng Hou, Han-Lun Wu and Yuan Chieh Wu, Numerical Simulation of a Neutrally Buoyant Round Jet in a Wave Environment, E-proceedings of the 36th IAHR World Congress, 28 June – 3 July, 2015, The Hague, the Netherlands

34-15   Dieter Vanneste and Peter Troch, 2D numerical simulation of large-scale physical model tests of wave interaction with a rubble-mound breakwater, Coastal Engineering, Volume 103, September 2015, Pages 22–41.

29-15   Masanobu Toyoda, Hiroki Kusumoto, and Kazuo Watanabe, Intrinsically Safe Cryogenic Cargo Containment System of IHI-SPB LNG Tank, IHI Engineering Review, Vol. 47, No. 2, 2015.

24-15   Xixi Pan, Shiming Wang, and Yongcheng Liang, Three-dimensional simulation of floating wave power device, International Power, Electronics and Materials Engineering Conference (IPEMEC 2015)

05-15   M. A. Bhinder, A. Babarit, L. Gentaz, and P. Ferrant, Potential Time Domain Model with Viscous Correction and CFD Analysis of a Generic Surging Floating Wave Energy Converter, (2015), doi: http://dx.doi.org/10.1016/j.ijome.2015.01.005

137-14   A. Najafi-Jilani, M. Zakiri Niri and Nader Naderi, Simulating three dimensional wave run-up over breakwaters covered by antifer units, Int. J. Nav. Archit. Ocean Eng. (2014) 6:297~306

128-14   Dong Chule Kim, Byung Ho Choi, Kyeong Ok Kim and Efim Pelinovsky, Extreme tsunami runup simulation at Babi Island due to 1992 Flores tsunami and Okushiri due to 1993 Hokkido tsunami, Geophysical Research Abstracts, Vol. 16, EGU2014-1341, 2014, EGU General Assembly 2014, © Author(s) 2013. CC Attribution 3.0 License.

123-14   Irkal Mohsin A.R., S. Nallayarasu and S.K. Bhattacharyya, Experimental and CFD Simulation of Roll Motion of Ship with Bilge Keel, International Conference on Computational and Experimental Marine Hydrodynamics MARHY 2014 3-4 December 2014, Chennai, India.

101-14  Dieter Vanneste, Corrado Altomare, Tomohiro Suzuki, Peter Troch and Toon Verwaest, Comparison of Numerical Models for Wave Overtopping and Impact on a Sea Wall, Coastal Engineering 2014

91-14   Fabio Dentale, Giovanna Donnarumma, and Eugenio Pugliese Carratelli, Numerical wave interaction with tetrapods breakwater, Int. J. Nav. Archit. Ocean Eng. (2014) 6:0~0, http://dx.doi.org/10.2478/IJNAOE-2013-0214, ⓒSNAK, 2014, pISSN: 2092-6782, eISSN: 2092-6790

87-14   Philipp Behruzi, Simulation of breaking wave impacts on a flat wall, The 15th International Workshop on Trends In Numerical and Physical Modeling for Industrial Multiphase Flows, Cargèse, Corsica, October 13th–17th, 2014

86-14   Chuan Sim and Sung-uk Choi, Three-Dimensional Scour at Submarine Pipelines under Indefinite Boundary Conditions, 2014

83-14   Hongda Shi, Dong Wang, Jinghui Song, and Zhe Ma, Systematic Design of a Heaving Buoy Wave Energy Device, 5th International Conference on Ocean Energy, 4th November, Halifax, 2014

71-14   Hadi Sabziyan, Hassan Ghassemi, Farhood Azarsina, and Saeid Kazemi, Effect of Mooring Lines Pattern in a Semi-submersible Platform at Surge and Sway Movements, Journal of Ocean Research, 2014, Vol. 2, No. 1, 17-22 Available online at http://pubs.sciepub.com/jor/2/1/4 © Science and Education Publishing DOI:10.12691/jor-2-1-4

56-14   Fernandez-Montblanc, T., Izquierdo, A., and Bethencourt, M., Modelling the oceanographic conditions during storm following the Battle of Trafalgar, Encuentro de la Oceanografıa Fısica Espanola 2014

52-14   Fabio Dentale, Giovanna Donnarumma, and Eugenio Pugliese Carratelli, A new numerical approach to the study of the interaction between wave motion and roubble mound breakwaters, Latest Trends in Engineering Mechanics, Structures, Engineering Geology, ISBN: 978-960-474-376-6

49-14   H. Ahmed and A. Schlenkhoff, Numerical Investigation of Wave Interaction with Double Vertical Slotted Walls, World Academy of Science, Engineering and Technology, International Journal of Environmental, Ecological, Geological and Mining Engineering Vol:8 No:8, 2014

32-14  Richard Keough, Victoria Mullaley, Hilary Sinclair, and Greg Walsh, Design, Fabrication and Testing of a Water Current Energy Device, Memorial University of Newfoundland, Faculty of Engineering and Applied Science, Mechanical Design Project II – ENGI 8926, April 2014

25-14    Paulius Rapalis, Vytautas Smailys, Vygintas Daukšys, Nadežda Zamiatina, and Vasilij Djačkov, Vandens  – Duju Silumos Mainai Gaz-Lifto Tipo Skruberyje,Technologijos mokslo darbai Vakarų Lietuvoje, Vol 9 > Rapalis. Available for download at http://journals.ku.lt/index.php/TMD/article/view/259.

92-13   Matteo Tirindelli, Scott Fenical and Vladimir Shepsis, State-of-the-Art Methods for Extreme Wave Loading on Bridges and Coastal Highways, Seventh National Seismic Conference on Bridges and Highways (7NSC), May 20-22, 2013, Oakland, CA

89-13 Worakanok Thanyamanta, Don Bass and David Molyneux, Prediction of sloshing effects using a coupled non-linear seakeeping and CFD code, Proceedings of the ASME 2013 32nd International Conference on Ocean, Offshore and Arctic Engineering, OMAE2013, June 9-14, 2013, Nantes, France. Available for purchase online at ASME.

83-13   B.W. Lee and C. Lee, Development of Wave Power Generation Device with Resonance Channels, Proceedings of the 7th International Conference on Asian and Pacific Coasts (APAC 2013) Bali, Indonesia, September 24-26, 2013

68-13   Fabio Dentale, Giovanna Donnarumma, and Eugenio Pugliese Carratelli, Rubble Mound Breakwater Run-Up, Reflection and Overtopping by Numerical 3D Simulation, ICE Conference, September 2013, Edinburgh (UK).

66-13  Peter Arnold, Validation of FLOW-3D against Experimental Data for an Axi-Symmetric Point Absorber WEC, © wavebob™, 2013

62-13 Yanan Li, Junwei Zhou, Dazheng Wang and Yonggang Cui, Resistance and Strength Analysis of Three Hulls with ifferent Knuckles, Advanced Materials Research Vols. 779-780 (2013) pp 615-618, © (2013) Trans Tech Publications, Switzerland, doi:10.4028/www.scientific.net/AMR.779-780.615.

61-13  M.R. Soliman, Satoru Ushijima, Nobu Miyagi and Tetsuay Sumi, Density Current Simulation Using Two-Dimensional High Resolution Model, Annuals of Disas. Prev. Res. Inst., Kyoto Univ., No 56 B, 2013.

59-13  Guang Wei Liu, Qing He Zhang, and Jin Feng Zhang, Wave Forces on the Composite Bucket Foundation of Offshore Wind Turbines, Applied Mechanics and Materials, 405-408, 1420, September 2013. Available for purchase online at Scientific.net.

50-13  Joel Darnell and Vladimir Shepsis, Pontoon Launch Analysis, Design and Performance, Ports 2013, © ASCE 2013. Available for purchase online at ASCE.

45-13 Min-chi Li, Numerical Simulation of Wave Overtopping Rate at Sloping Seawalls with Different Configurations of Wave Dissipators, Master’s Thesis: Department of Marine Environment and Engineering, National Sun Yat-Sen University. Abstract only available here: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0701113-144919.

22-13  Nahidul Khan, Jonathan Smith, and Michael Hinchey, Models with all the right curves, © Journal of Ocean Technology, The Journal of Ocean Technology, Vol. 8, No. 1, 2013.

20-13  Efim Pelinovsky, Dong-Chul Kim, Kyeong-Ok Kim and Byung-Ho Choi, Three-dimensional simulation of extreme runup heights during the 2004 Indonesian and 2011 Japanese tsunamis, EGU General Assembly 2013, held 7-12 April, 2013 in Vienna, Austria, id. EGU2013-1760. Online at: http://adsabs.harvard.edu/abs/2013EGUGA..15.1760P.

18-13 Dazheng Wang, Fei Ma, and Lei Mei, Optimization of a 17m Catamaran based on the Resistance Performance, Advanced Materials Research Vols. 690-693, pp 3414-3418, © Trans Tech Publications, Switzerland, doi:10.4028/www.scientific.net/AMR.690-693.3414, May 2013.

16-13  Dong Chule Kim, Kyeong Ok Kim, Efim Pelinovsky, Ira Didenkulova, and Byung Ho Choi, Three-dimensional tsunami runup simulation for the port of Koborinai on the Sanriku coast of Japan, Journal of Coastal Research, Special Issue No. 65, 2013.

15-13  Dong Chule Kim, Kyeong Ok Kim, Byung Ho Choi, Kyung Hwan Kim, and Efin Pelinovsky, Three –dimensional runup simulation of the 2004 Ocean tsunami at the Lhok Nga twin peaks, Journal of Coastal Research, Special Issue No. 65, 2013.

14-13  Jae-Seol Shim, Jinah Kim, Dong-Shul Kim, Kiyoung Heo, Kideok Do, and Sun-Jung Park, Storm surge inundation simulations comparing three-dimensional with two-dimensional models based on Typhoon Maemi over Masan Bay of South Korea, Journal of Coastal Research, Special Issue No. 65, 2013.

115-12  Worakanok Thanyamanta and David Molyneux, Prediction of Stabilizing Moments and Effects of U-Tube Anti-Roll Tank Geometry Using CFD, ASME 2012 31st International Conference on Ocean, Offshore and Arctic Engineering, Volume 5: Ocean Engineering; CFD and VIV, Rio de Janeiro, Brazil, July 1–6, 2012, ISBN: 978-0-7918-4492-2, Copyright © 2012 by ASME

114-12   Dane Kristopher Behrens, The Russian River Estuary: Inlet Morphology, Management, and Estuarine Scalar Field Response, Ph.D. Thesis: Civil and Environmental Engineering, UC Davis, © 2012 by Dane Kristopher Behrens. All Rights Reserved.

111-12  James E. Beget, Zygmunt Kowalik, Juan Horrillo, Fahad Mohammed, Brian C. McFall, and Gyeong-Bo Kim, NEeSR-CR Tsunami Generation by Landslides Integrating Laboratory Scale Experiments, Numerical Models and Natural Scale Applications, George E. Brown, Jr. Network for Earthquake Engineering Simulation Research, July 2012, Boston, MA.

110-12   Gyeong-Bo Kim, Numerical Simulation of Three-Dimensional Tsunami Generation by Subaerial Landslides, M.S. Thesis: Texas A&M University, Copyright 2012 Gyeong-Bo Kim, December 2012

109-12 D. Vanneste, Experimental and Numerical study of Wave-Induced Porous Flow in Rubble-Mound Breakwaters, Ph.D. thesis (Chapters 5 and 6), Faculty of Engineering and Architecture, Ghent University, Ghent (Belgium), 2012.

104-12 Junwoo Choi, Kab Keun Kwon, and Sung Bum Yoon, Tsunami Inundation Simulation of a Built-up Area using Equivalent Resistance Coefficient, Coastal Engineering Journal, Vol. 54, No. 2 (2012) 1250015 (25 pages), © World Scientific Publishing Company and Japan Society of Civil Engineers, DOI: 10.1142/S0578563412500155

94-12 Parviz Ghadimi, Abbas Dashtimanesh, Mohammad Farsi, and Saeed Najafi, Investigation of free surface flow generated by a planing flat plate using smoothed particle hydrodynamics method and FLOW-3D simulations, Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, December 7, 2012 1475090212465235. Available for purchase online at sage journals.

92-12    Panayotis Prinos, Maria Tsakiri, and Dimitris Souliotis, A Numerical Simulation of the WOS and the Wave Propagation along a Coastal Dike, Coastal Engineering 2012.

88-12  Nahidul Khan and Michael Hinchey, Adaptive Backstepping Control of Marine Current Energy Conversion System, PKP Open Conference Systems, IEEE Newfoundland and Labrador Section, 2012.

72-12   F. Dentale, G. Donnarumma, and E. Pugliese Carratelli, Wave Run Up and Reflection on Tridimensional Virtual, Journal of Hydrogeology & Hydrologic Engineering, 2012, 1:1, http://dx.doi.org/10.4172/jhhe.1000102.

64-12  Anders Wedel Nielsen, Xiaofeng Liu, B. Mutlu Sumer, Jørgen Fredsøe, Flow and bed shear stresses in scour protections around a pile in a current, Coastal Engineering, Volume 72, February 2013, Pages 20–38.

56-12  Giancarlo Alfonsi, Agostino Lauria, Leonardo Primavera, Flow structures around large-diameter circular cylinder, Journal of Flow Visualization and Image Processing, 2012. DOI:10.1615/JFlowVisImageProc.2012005088.

51-12  Chun-Ho Chen, Study on the Application of FLOW-3D for Wave Energy Dissipation by a Porous Structure, Master’s Thesis: Department of Marine Environment and Engineering, National Sun Yat-sen University, July 2012. In Chinese.

37-12  Yu-Ren Chen, Numerical Modeling on Internal Solitary Wave propagation over an obstacle using FLOW-3D, Master’s Thesis: Department of Marine Environment and Engineering, National Sun Yat-sen University June 2012. In Chinese.

26-12  D.C. Lo Numerical simulation of hydrodynamic interaction produced during the overtaking and the head-on encounter process of two ships, Engineering Computations: International Journal for Computer-Aided Engineering and Software, Vol. 29 No. 1, 2012. pp. 83-10, Emerald Group Publishing Limited, www.emeraldinsight.com/0264-4401.htm.

14-12  Bahaa Elsharnouby, Akram Soliman, Mohamed Elnaggar, and Mohamed Elshahat, Study of environment friendly porous suspended breakwater for the Egyptian Northwestern Coast, Ocean Engineering 48 (2012) 47-58. Available for purchase online at Science Direct.

11-12  Sang-Ho Oh, Young Min Oh, Ji-Young Kim, Keum-Seok Kang, A case study on the design of condenser effluent outlet of thermal power plant to reduce foam emitted to surrounding seacoast, Ocean Engineering, Volume 47, June 2012, Pages 58–64. Available for purchase online at SciVerse.

101-11 Tsunami – A Growing Disaster, edited by Mohammad Mokhtari, ISBN 978-953-307-431-3, 232 pages, Publisher: InTech, Chapters published December 16, 2011 under CC BY 3.0 license, DOI: 10.5772/922. Available for download at Intech.

100-11 Kwang-Oh Ko, Jun-Woo Choi, Sung-Bum Yoon, and Chang-Beom Park, Internal Wave Generation in FLOW-3D Model, Proceedings of the Twenty-first (2011) International Offshore and Polar Engineering Conference, Maui, Hawaii, USA, June 19-24, 2011, Copyright © 2011 by the International Society of Offshore and Polar Engineers (ISOPE), ISBN 978-1-880653-96-8 (Set); ISSN 1098-6189 (Set); www.isope.org

95-11  S. Brizzolara, L. Savio, M. Viviani, Y. Chen, P. Temarel, N. Couty, S. Hoflack, L. Diebold, N. Moirod and A. Souto Iglesias, Comparison of experimental and numerical sloshing loads in partially filled tanks, Ships and Offshore StructuresVol. 6, Nos. 1–2, 2011, 15–43. Available for purchase online at Francis & Taylor.

85-11 Andrew Eoghan Maguire, Hydrodynamics, control and numerical modelling of absorbing wavemakers, thesis: The University of Edinburgh, 2011.

74-11  Jonathan Smith, Nahidul Khan and Michael Hinchey, CFD Simulation of AUV Depth Control, Paper presented at NECEC 2011, St. John’s, Newfoundland and Labrador, Canada. Abstract available online.

70-11  G. Kim, S.-H. Oh, K.S. Lee, I.S. Han, J.W. Chae, and S.-J Ahn, Numerical Investigation on Water Discharge Capability of Sluice Caisson of Tidal Power Plant, Proceedings of the Sixth International Conference on Asian and Pacific Coasts (APAC 2011), December 14-16, 2011, Hong Kong, China.

69-11  G. Alfonsi, A. Lauria, and L. Primavera, Wave-Field Flow Structures Developing Around Large-Diameter Vertical Circular Cylinder, Proceedings of the Sixth International Conference on Asian and Pacific Coasts (APAC 2011), December 14-16, 2011, Hong Kong, China.

68-11    C. Lee, B.W. Lee, Y.J. Kim, and K.O. Ko, Ship Wave Crests in Intermediate-Depth Water, Proceedings of the Sixth International Conference on Asian and Pacific Coasts (APAC 2011), December 14-16, 2011, Hong Kong, China.

63-11   Worakanok Thanyamanta, Paul Herrington, and David Molyneux, Wave patterns, wave induced forces and moments for a gravity based structure predicted using CFD, Proceedings of the ASME 2011, 30th International Conference on Ocean, Offshore and Arctic Engineering, OMAE2011, Rotterdam, The Netherlands, June 19-24, 2011.

61-11  Jun Jin and Bo Meng, Computation of wave loads on the superstructures of coastal highway bridges, Ocean Engineering, available online October 19, 2011, ISSN 0029-8018, 10.1016/j.oceaneng.2011.09.029. Available for purchase at Science Direct.

36-11    Nadir Yilmaz, Geoffrey E. Trapp, Scott M. Gagan, Timothy R. Emmerich, CFD Supported Examination of Buoy Design for Wave Energy Conversion, IGEC-VI-2011-173, pp: 537-541

28-11  Rodolfo Bolaños, Laurent O. Amoudry and Ken Doyle, Effects of Instrumented Bottom Tripods on Process Measurements, Journal of Atmospheric and Oceanic Technology, June 2011, Vol. 28, No. 6: pp. 827-837. Available online at: AMS Journals Online.

81-10    Ashwin Lohithakshan Parambath, Impact of Tsunamis on Near Shore Wind Power Units, M.S. Thesis: Texas A&M University, Copyright 2010 Ashwin Lohithakshan Parambath December 2010.

80-10    Juan J. Horrillo, Amanda L. Wood, Charles Williams, Ashwin Parambath, and Gyeong-Bo Kim, Construction of Tsunami Inundation Maps in the Gulf of Mexico, Report to the National Tsunami Hazard Mitigation Program, December 2010.

69-10    George A Aggidis and Clive Mingham, A Joint Numerical and Experimental Study of a Surging Point Absorbing Wave Energy Converter (WRASPA), Joule Centre Research Grant Joint Final Report (Lancaster University and Macnhester Metropolitan University), Joule Grant No: JIRP306/02, 2010

67-10  Kazuhiko Terashima, Ryuji Ito, Yoshiyuki Noda, Yoji Masui and Takahiro Iwasa, Innovative Integrated Simulator for Agile Control Design on Shipboard Crane Considering Ship and Load Sway, 2010 IEEE International Conference on Control Applications, Part of 2010 IEEE Multi-Conference on Systems and Control, Yokohama, Japan, September 8-10, 2010

66-10  Shan-Hwei Ou, Tai-Wen Hsu, Jian-Feng Lin, Jian-Wu Lai, Shih-Hsiang Lin, Chen-Chen Chang, Yuan-Jyh Lan, Experimental and Numerical Studies on Wave Transformation over Artificial Reefs, Proceedings of the International Conference on Coastal Engineering, No 32 (2010), Shanghai, China, 2010.

65-10 Tai-Wen Hsu, Jian-Wu Lai, Yuan-Jyh Lan, Experimental and Numerical Studies on Wave Propagation over Coarse Grained Sloping Beach, Proceedings of the International Conference on Coastal Engineering, No 32 (2010), Shanghai, China, 2010.

26-10 R. Marcer, C. Berhault, C. de Jouëtte, N. Moirod and L. Shen, Validation of CFD Codes for Slamming, V European Conference on Computational Fluid Dynamics, ECCOMAS CFD 2010, J.C.F. Pereira and A. Sequeira (Eds), Lisbon, Portugal, 14-17 June 2010

25-10 J.M. Zhan, Z. Dong, W. Jiang, and Y.S. Li, Numerical Simulation of wave transformation and runup incorporating porous media wave absorber and turbulence models, Ocean Engineering (2010), doi: 10.1016/j.oceaneng.2010.06.005. Available for purchase at Science Direct.

17-10 F. Dentale, S.D. Russo, E. Pugliese Carratelli, S. Mascetti, A New Numerical Approach to Study the Wave Motion with Breakwaters and the Armor Stability, Marine Technology Reporter, May 2010

01-10 F. Dentale, S.D. Russo, E. Pugliese Carratelli, Innovative Numerical Simulation to Study the Fluid withing Rubble Mound Breakwaters and the Armour Stability, 17th Armourstone Wallingford Armourstone Meeting, Wallingford, UK, February 2010.

52-09  Mark Reed, Øistein Johansen, Frode Leirvik, and Bård Brørs, Numerical Algorithm to Compute the Effects of Breaking Waves on Surface Oil Spilled at Sea, Final Report, Second revision, SINTEF, October 2009.

49-09  Anna Pellicioli, Indagine Numerica Sulla Resistenza Idrodinamica Di Uno Scafo In Presenza Di Superficie Libera, thesis: Univerista Degli Studi Di Bergamo, 2008/2009. In Italian. Available upon request.

46-09 Carlos Guedes Soares, P.K. Das, Analysis and Design of Marine Structures, CRC Press; 1 Har/Cdr edition (March 2, 2009), 0415549345

32-09 M.A. Binder, C.G. Mingham, D.M. Causon, M.T. Rahmati, G.A. Aggidis, R.V. Chaplin, Numerical Modelling of a Surging Point Absorber Wave Energy Converter, 8th European Wave and Tidal Energy Conference EWTEC 2009, Uppsala, Sweden, 7-10 September 2009

28-09 D. C. Lo, Dong-Taur Su and Jan-Ming Chen (2009), Application of Computational Fluid Dynamics Simulations to the Analysis of Bank Effects in Restricted Waters, Journal of Navigation, 62, pp 477-491, doi:10.1017/S037346330900527X; Purchase the article online (clicking on this link will take you to the Cambridge Journals website).

26-09 Fabio Dentale, E. Pugliese Carratelli, S.D. Russo, and Stefano Mascetti, Advanced Numerical Simulations on the Interaction between Waves and Rubble Mound Breakwaters, Journal of the Engineering Association for Offshore and Marine in Italy, (translation from the Italian)

25-09 F. Dentale, B. Messina, E. Pugliese Carratelli, S. Mascetti, Studio numerico avanzato sul moto di filtrazione in ambito marittimo, A & C, Analisi e Calcolo, Giugno 2009 (in Italian)

22-09 M.A. Bhinder, C.G. Mingham, D.M. Causon, M.T. Rahmati, G.A. Aggidis and R.V. Chaplin, A Joint Numerical And Experimental Study Of a Surging Point Absorbing Wave Energy Converter (WRASPA)2, Proceedings of the ASME 28th International Conference on Ocean, Offshore and Arctic Engineering, OMAE2009-79392, Honolulu, Hawaii, May 31-June 5, 2009

8-09 Basu, D., S. Green, K. Das, R. Janetzke, and J. Stamatakos, Numerical Simulation of Surface Waves Generated by a Subaerial Landslide at Lituya Bay, 28th International Conference on Ocean, Offshore and Arctic Engineering, May 31–June 5, 2009, Honolulu, Hawaii

17-09 Das, K., R. Janetzke, D. Basu, S. Green, and J. Stamatakos, Numerical Simulations of Tsunami Wave Generation by Submarine and Aerial Landslides Using RANS and SPH Models, 28th International Conference on Ocean, Offshore and Arctic Engineering, May 31–June 5, 2009, Honolulu, Hawaii

16-09 Basu, D., S. Green, K. Das, R. Janetzke, and J. Stamatakos, Navier-Stokes Simulations of Surface Waves Generated by Submarine Landslides Effect of Slide Geometry and Turbulence, 2009 Society of Petroleum Engineering Americas E&P Environmental & Safety Conference, March 23–25, 2009, San Antonio, Texas.

48-08    Osamu Kiyomiya1 and Kazuya Kuroki, Flap Gate to Prevent Urban Area from Tsunami, The 14th World Conference on Earthquake Engineering, October 12-17, 2008, Beijing, China

43-08  Eldina Fatimah, Ahmad Khairi Abd. Wahab, and Hadibah Ismail, Numerical modeling approach of an artificial mangrove root system (ArMs) submerged breakwater as wetland habitat protector, COPEDEC VII, Dubai UAE, 2008.

40-08 Giacomo Viccione, Fabio Dentale, and Vittorio Bovolin, Simulation of Wave Impact Pressure on Vertical Structures with the SPH Method, 3rd ERCOFTAC SPHERIC workshop on SPH applications, Laussanne, Switzerland, June 4-6, 2008.

39-08 Kang, Young-Seung, Kim, Pyeong-Joong, Hyun, Sang-Kwon and Sung, Ha-Keun, Numerical Simulation of Ship-induced Wave Using FLOW-3D, Journal of Korean Society of Coastal and Ocean Engineers / v.20, no.3, 2008, pp.255-267, ISSN: 1976-8192, http://ksci.kisti.re.kr/search/article/articleView.ksci?articleBean.artSeq=HOHODK_2008_v20n3_255

35-08 B.W. Nam, S.H. Shin, K.Y. Hong, S.W. Hong, Numerical Simulation of Wave Flow over the Spiral-Reef Overtopping Device, Proceedings of the Eighth (2008) ISOPE Pacific/Asia Offshore Mechanics Symposium, Bangkok, Thailand, November 10-14, 2008, © 2008 by The International Society of Offshore and Polar Engineers, ISBN 978-1-880653-52-4

34-08 B. H. Choi, E. Pelinovsky, D.C. Kim, I. Didenkulova and S.-B. Woo, Two and three-dimensional computation of solitary wave runup on non-plane beach, Nonlin. Processes Geophys., 15, 489-502, 2008, www.nonlin-processes-geophys.net/15/489/2008 (c) Author(s) 2008.

23-08 Barb Schmitz, Tecplot, Nastran & FLOW-3D Win the Race, Desktop Engineering’s Elements of Analysis, September 2008

38-07 Choi, B.-H., Kim, D. C., Pelinovsky, E., and Woo, S. B., Three-dimensional simulation of tsunami run-up around conical island, Coast. Eng., Vol. 54, Issue 8, 618-629, 2007.

33-07 Mirela Zalar, Sime Malenica, Zoran Mravak, Nicolas Moirod, Some Aspects of Direct Calculation Methods for the Assessment of LNG Tank Structure Under Sloshing Impacts, La Asociación Española del Gas (sedigas) Spain 2007

20-07 Oceanic Consulting Corporation, Berthing Studies for LNG Carriers in the Calcasieu River Waterway, Making Waves: Newsletter of Oceanic Consulting Corporation, Winter 2007

10-07 Gildas Colleter, Breaking wave uplift and overtopping on a horizontal deck using physical and numerical modeling, Coasts and Ports 2007 Conference in Melbourne, Australia

18-06 Brizzolara, Stefano and Rizzuto, Enrico, Wind Heeling Moments on Very Large Ships. Some Insights through CFD Results, Proceedings on the 9th International Conference on Stability of Ships and Ocean Vehicles, Rio de Janeiro, September 25, 2006

16-06 Ransau, Samuel R, and Hansen, Ernst W.M., Numerical Simulations of Sloshing in Rectangular Tanks, Proceedings of OMAE2006, 25th International Conference on Offshore Mechanics and Arctic Engineering, Hamburg, Germany, June 4-9, 2006

15-06 Ema Muk-Pavic, Shin Chin and Don Spencer, Validation of the CFD code FLOW-3D for the free surface flow around the ships’; hulls, 14th Annual Conference of the CFD Society of Canada, Kingston, Canada, July 16-18, 2006

3-06 Hansen, E.W.M. and Geir J. Rørtveit, Numerical Simulation of Fluid Mechanisms and Separation Behaviour in Offshore Gravity Separators, Chapter 16 in Emulsions and Emulsion Stability, 2nd Edition, edited by Johan Sjøblom, Taylor & Francis, 2006

24-05 Hansen E.W., Separation Offshore Survey – Design-Redesign of Gravity Separators, Exploration & Production: The Oil & Gas Review 2005 – Issue 2

8-05 T. Kristiansen, R. Baarholm, C.T. Stansberg, G. Rortveit and E.W.M. Hansen, Kinematics in a Diffracted Wave Field Particle Image Velocimetry (PIV) and Numerical Models, Presented at the 24th International Conference on Offshore Mechanics and Arctic Engineering, OMAE 67176, Halkidiki, Greece, June 12-17, 2005

7-05 C.T. Stansberg, R. Baarholm, T. Kristiansen, E.W.M. Hansen and G. Rortveit, Extreme Wave Amplification and Impact Loads on Offshore Structures, presented at the 2005 Offshore Technology Conference, Houston, TX, May 2-5, 2005

16-04 Carl Trygve Stansberg, Kjetil Berget, Oyvind Hellan, Ole A. Hermundstad, Jan R. Hoff and Trygve Kristiansen and Ernst Hansen, Prediction of Green Sea Loads on FPSO in Random Seas, presented at the 14th International Offshore and Polar Engineering Conference (ISOPE 2004), Toulon, France, May 2004

15-04 Š. Malenica, M. Zalar, J.M. Orozco, B. LeGallo & X.B. Chen, Linear and Non-Linear Effects of Sloshing on Ship Motions, 23rd International Conference on Offshore Mechanics and Artic Engineering, OMAE 2004, Vancouver, June 2004

11-04 Don Bass, David Molyneux, Kevin McTaggart, Simulating Wave Action in the Well Deck of Landing Platform Dock Ships Using Computational Fluid Dynamics

37-03  Sreenivasa C Chopakatla, A CFD Model for Wave Transformations and Breaking in the Surf Zone, thesis: Master of Science, The Ohio State Univeristy, 2003.

29-02   O. Bayle, V. L’Hullier, M. Ganet, P. Delpy, J.L. Francart and D. Paris, Influence of the ATV Propellant Sloshing on the GNC Performance, AIAA Guidance, Navigation, and Control Conference and Exhibit, Monterey, California, 5-8 August 2002, © 2002 by EADS Launch Vehicles

25-02 Y. Kim, Numerical Analysis of Sloshing Problem, American Bureau of Shipping, Research Dept, Houston, TX

10-02 Peter Chang III & Xiongjun Wu, Entrainment Correlations Based on a Fuel-Water Stratified Shear Flow, Proceedings of FEDSM2002, 2002 ASME Fluids Engineering Decision Summer Meeting, July 14-18, 2002, Montreal, Quebec, Canada

37-01 Ismail B. Celik, Allen E. Badeau Jr., Andrew Burt and Sherif Kandil, A Single Fluid Transport Model For Computation of Stratified Immiscible Liquid-Liquid Flows, Mechanical and Aerospace Engineering Department, West Virginia University, Proceedings of the XXIX IAHR Congress, September 2001. Beijing, China

14-01 Charles Ortloff, CTC/United Defense, Computer Simulation Analyzed Typhoon Damage to FPSOs, Marine News, April 30, 2001, pp. 22-23

8-01 Charles Ortloff, Computer Simulations Analyze Wave Damage to Offloading Vessels, Marine News, April 30, 2001, pp. 22-23

25-00 Faltinsen, O.A. and Rognebakke, O.F., Sloshing in Rectangular Tanks and Interaction with Ship Motions-Sloshing, Int. Conf. on Ship and Shipping Research NAV, Venice, Italy, 2000.

20-97   C.R. Ortloff, Numerical Test Tank Simulation of Ocean Engineering Problems by Computational Fluid Dynamics, Offshore Technology Conference Paper 8269B, Houston, TX, 1997

19-97   C.R. Ortloff and M. Krafft, Numerical Test Tanks-Computer Simulation-Test Verification of Major Ocean Engineering Problems for the Off-Shore Oil Industry, OTC 8269A, Offshore Technology Conference, Copyright 1997, Houston, Texas, May 1997

9-94 P. A. Chang, C-W Lin, CD-NSWC, Hydrodynamic Analysis of Oil Outflow from Double Hull Tankers, The Advanced Double-Hull Technical Symposium, Gaithersburg, MD, October 25-26, 1994.

8-90 C. W. Hirt, Computational Modeling of Cavitation, Flow Science report, July 1990, presented at the 2nd International Symposium on Performance Enhancement for Marine Applications, Newport, RI, October 14-16, 1990

10-87 H. W. Meldner, USA’s Revolutionary Appendages and CFD, CORDTRAN Corp. Report presented at AIAA and SNAME 17th Annual International Symposium on Sailing, Stanford University, Palo Alto, CA, Oct. 31-Nov. 1, 1987

3-85 C. W. Hirt and J. M. Sicilian, A Porosity Technique for the Definition of Obstacles in Rectangular Cell Meshes, Fourth International Conference on Ship Hydrodynamics, Washington, DC, September 1985

Water & Environmental Bibliography

다음은 수자원 및 환경 분야에 대한 참고 문 기술 문서 모음입니다.
이 모든 논문은 FLOW-3D  해석 결과를 사용하였습니다. FLOW-3D  를 사용하여 수처리 및 환경 산업을 위한 응용 프로그램을 성공적으로 시뮬레이션하는 방법에 대해 자세히 알아보십시오.

Water and Environmental Bibliography

2024년 3월 20일 Update

209-23   Cong Trieu Tran, Cong Ty Trinh, Prediction of the vortex evolution and influence analysis of rough bed in a hydraulic jump with the Omega-Liutex method, Tehnički Vjesnik, 30.6; 2023. doi.org/10.17559/TV-20230206000327

203-23   Muhammad Waqas Zaffar, Ishtiaq Hassan, Zulfiqar Ali, Kaleem Sarwar, Muhammad Hassan, Muhammad Taimoor Mustafa, Faizan Ahmed Waris, Numerical investigation of hydraulic jumps with USBR and wedge-shaped baffle block basins for lower tailwater, AQUA – Water Infrastructure, Ecosystems and Society, 72.11; 2081, 2023. doi.org/10.2166/aqua.2023.261

201-23   E.F.R. Bollaert, Digital cloud-based platform to predict rock scour at high-head dams, Role of Dams and Reservoirs in a Successful Energy Transition, Eds. Robert Boes, Patrice Droz, Raphael Leroy, 2023. doi.org/10.1201/9781003440420

200-23   Iacopo Vona, Oysters’ integration on submerged breakwaters as nature-based solution for coastal protection within estuarine environments, Thesis, University of Maryland, 2023.

198-23   Hao Chen, Xianbin Teng, Zhibin Zhang, Faxin Zhu, Jie Wang, Zhaohao Zhang, Numerical analysis of the influence of the impinging distance on the scouring efficiency of submerged jets, Fluid Dynamics & Materials Processing, 20.2; pp. 429-445, 2023. doi.org/10.32604/fdmp.2023.030585

193-23   Chen Peng, Liuweikai Gu, Qiming Zhong, Numerical simulation of dam failure process based on FLOW-3D, Advances in Frontier Research on Engineering Structures, pp. 545-550, 2023. doi.org/10.3233/ATDE230245

189-23   Rebecca G. Englert, Age J. Vellinga, Matthieu J.B. Cartigny, Michael A. Clare, Joris T. Eggenhuisen, Stephen M. Hubbard, Controls on upstream-migrating bed forms in sandy submarine channels, Geology, 51.12; PP. 1137-1142, 2023. doi.org/10.1130/G51385.1

187-23   J.W. Kim, S.B. Woo, A numerical approach to the treatment of submerged water exchange processes through the sluice gates of a tidal power plant, Renewable Energy, 219.1; 119408, 2023. doi.org/10.1016/j.renene.2023.119408

186-23   Chan Jin Jeong, Hyung Jun Park, Hyung Suk Kim, Seung Oh Lee, Study on fish-friendly flow characteristic in stepped fishway, Proceedings of the Korean Water Resources Association Conference, 2023. (In Korean)

185-23   Jaehwan Yoo, Sedong Jang, Byunghyun Kim, Analysis of coastal city flooding in 2D and 3D considering extreme conditions and climate change, Proceedings of the Korean Water Resources Association Conference, 2023. (In Korean)

180-23   Prathyush Nallamothu, Jonathan Gregory, Jordan Leh, Daniel P. Zielinski, Jesse L. Eickholt, Semi-automated inquiry of fish launch angle and speed for hazard analysis, Fishes, 8.10; 476, 2023. doi.org/10.3390/fishes8100476

179-23   Reza Norouzi, Parisa Ebadzadeh, Veli Sume, Rasoul Daneshfaraz, Upstream vortices of a sluice gate: an experimental and numerical study, AQUA – Water Infrastructure, Ecosystems and Society, 72.10; 1906, 2023. doi.org/10.2166/aqua.2023.269

178-23   Bai Hao Li, How Tion Puay, Muhammad Azfar Bin Hamidi, Influence of spur dike’s angle on sand bar formation in a rectangular channel, IOP Conference Series: Earth and Environmental Science, 1238; 012027, 2023. doi.org/10.1088/1755-1315/1238/1/012027

177-23   Hao Zhe Khor, How Tion Puay, Influence of gate lip angle on downpull forces for vertical lift gates, IOP Conference Series: Earth and Environmental Science, 1238; 012019, 2023. doi.org/10.1088/1755-1315/1238/1/012019

175-23   Juan Francisco Macián-Pérez, Rafael García-Bartual, P. Amparo López-Jiménez, Francisco José Vallés-Morán, Numerical modeling of hydraulic jumps at negative steps to improve energy dissipation in stilling basins, Applied Water Science, 13.203; 2023. doi.org/10.1007/s13201-023-01985-4

174-23   Ahintha Kandamby, Dusty Myers, Narrows bypass chute CFD analysis, Dam Safety, 2023.

173-23   H. Jalili, R.C. Mahon, M.F. Martinez, J.W. Nicklow, Sediment sluicing from the reservoirs with high efficiency, SEDHYD, 2023.

170-23   Ramith Fernando, Gangfu Zhang, Beyond 2D: Unravelling bridge hydraulics with CFD modelling, 24th Queensland Water Symposium, 2023.

169-23   K. Licht, G. Lončar, H. Posavčić, I. Halkijević, Short-time numerical simulation of ultrasonically assisted electrochemical removal of strontium from water, 18th International Conference on Environmental Science and Technology (CEST), 2023.

166-23   Ebrahim Hamid Hussein Al-Qadami, Mohd Adib Mohammad Razi, Wawan Septiawan Damanik, Zahiraniza Mustaffa, Eduardo Martinez-Gomariz, Fang Yenn Teo, Anwar Ameen Hezam Saeed, Understanding the stability of passenger vehicles exposed to water flows through 3D CFD modelling, Sustainability, 15.17; 13262, 2023. doi.org/10.3390/su151713262

165-23   Ebrahim Hamid Hussein Al-Qadami, Mohd Adib Mohammad Razi, Wawan Septiawan Damanik, Zahiraniza Mustaffa, Eduardo Martinez-Gomariz, Fang Yenn Teo, Anwar Ameen Hezam Saeed, 3-dimensional numerical study on the critical orientation of the flooded passenger vehicles, Engineering Letters, 31.3; 2023.

159-23 Ruosi Zha, Weiwen Zhao, Decheng Wan, Numerical study of wave-ice floe interactions and overwash by a meshfree particle method, Ocean Engineering, 286.2; 115681, 2023. doi.org/10.1016/j.oceaneng.2023.115681

157-23 Hamidreza Abbaszadeh, Kiyoumars Roushangar, Zahra Salahpour, Theoretical and numerical investigation of the sluice and radial gates discharge coefficient in the conditions of sill application, Iranian Journal of Irrigation and Drainage, 2023.

155-23 Ting Zhang, Qunwei Dai, Dejun An, R. Agustin Mors, Qiongfang Li, Ricardo A. Astini, Jingwen He, Jie Cui, Ruiyang Jiang, Faqin Dong, Zheng Dang, Effective mechanisms in the formation of pool-rimstone dams in continental carbonate systems: The case study of Huanglong, China, Sedimentary Geology, 455; 106486, 2023. doi.org/10.1016/j.sedgeo.2023.106486

153-23 Jyh-Haw Tang, Aisyah Puspasari, Numerical simulation of scouring around four cylindrical piles with different inclination angles arrangements, Proceedings of the 4th International Conference on Advanced Engineering and Technology (ICATECH), 1; pp. 139-145, 2023. doi.org/10.5220/0012115500003680

152-23 Yasser El-Saie, Osama Saleh, Marihan El-Sayed, Abdelazim Ali, Eslam El-Tohamy, Yasser Mohamed Sadek, Dissipation of water energy by using a special stilling basin via three-dimensional numerical model, The Open Civil Engineering Journal, 17; 2023.

150-23 Shelby J. Koldewyn, Using computational fluid dynamics for predicting hydraulic performance of arced labyrinth weirs, Thesis, Utah State University, 2023.

146-23 Lav Kumar Gupta, Manish Pandey, P. Anand Raj, Numerical modeling of scour and erosion processes around spur dike, CLEAN Soil Air Water, 2023. doi.org/10.1002/clen.202300135

145-23 Nariman Mehranfar, Morteza Kolahdoozan, Shervin Faghihirad, Development of multiphase solver for the modeling of turbidity currents (the case study of Dez Dam), International Journal of Multiphase Flow, 168; 104586, 2023. doi.org/10.1016/j.ijmultiphaseflow.2023.104586

143-23 Fei Ma, Lei You, Jin Liu, Estimation in jet deflection angle of deflector on the chutes, ISH Journal of Hydraulic Engineering, 2023. doi.org/10.1080/09715010.2023.2241416

142-23 Ali Emre Ulu, M. Cihan Aydin, Fevzi Önen, Energy dissipation potentials of grouped spur dikes in an open channel, Water Resources Management, 37; pp. 4491-4506, 2023. doi.org/10.1007/s11269-023-03571-4

141-23 Haofei Feng, Shengtao Du, David Z. Zhu, Numerical study of effects of flushing gate height and sediment bed properties on cleaning efficiency in a simplified self-cleaning device, Water Science & Technology, 88.3; pp. 542-555, 2023. doi.org/10.2166/wst.2023.245

140-23 Brian Fox, 3D CFD modeling with FLOW-3D HYDRO, Proceedings, SEDHYD, 2023.

139-23 Masoumeh (Negar) Ghahramani, Improved empirical and numerical predictive modelling of potential tailings dam breaches and their downstream impacts, Thesis, The University of British Columbia, 2023.

138-23 Rui-Tao Yin, Bing Zhu, Shuai-Wei Yuan, Jun-Nan Li, Zhen-Yu Yang, Zhi-Ying Yang, Dynamic analyses of long-span cable-stayed and suspension cooperative system bridge under combined actions of wind and regular wave loads, Applied Ocean Research, 138; 103683, 2023. doi.org/10.1016/j.apor.2023.103683

137-23 Xuefeng Chen, Shikang Liu, Yuanming Wang, Yuetong Hao, Kefeng Li, Hongtao Wang, Ruifeng Liang, Restoration of a fish-attracting flow field downstream of a dam based on the swimming ability of endemic fishes: A case study in the upper Yangtze River basin, Journal of Environmental Management, 345; 118694, 2023. doi.org/10.1016/j.jenvman.2023.118694

135-23 Nelson Cely Calixto, Melquisedec Cortés Zambrano, Alberto Galvis Castaño, Gustavo Carrillo Soto, Analysis of a three-dimensional numerical modeling approach for predicting scour processes in longitudinal walls of granular bedding rivers, EUREKA: Physics and Engineering, 4; 2023. doi.org/10.21303/2461-4262.2023.002682

134-23 Tarek Selim, Abdelrahman Kamal Hamed, Mohamed Elkiki, Mohamed Galal Eltarabily, Numerical investigation of flow characteristics and energy dissipation over piano key and trapezoidal labyrinth weirs under free-flow conditions, Modeling Earth Systems and Environment, 2023. doi.org/10.1007/s40808-023-01844-w

132-23 Gang Lei, Hongbao Huang, Xiongan Fan, Junan Su, Qingxiang Wang, Xiaoliang Wang, Kai Peng, Jianmin Zhang, Influence of the transition section shape on the cavitation characteristics of the bottom outlet, Water Supply, 23.8; pp. 3061-3077, 2023. doi.org/10.2166/ws.2023.181

129-23 Rasoul Daneshfaraz, Reza Norouzi, John Patrick Abraham, Parisa Ebadzadeh, Behnaz Akhondi, Maryam Abar, Determination of flow characteristics over sharp-crested triangular plan form weirs using numerical simulation, Water Science, 37.1; 2023. doi.org/10.1080/23570008.2023.2236384

124-23 Imad Habeeb Obead, Ahmed Rahim Sahib, Mathematical models for simulating the hydraulic behavior of flow deflectors: laboratory and CFD-based study, Innovative Infrastructure Solutions, 8; 213, 2023. doi.org/10.1007/s41062-023-01170-1

120-23 Kwang-Su Kim, Jong-Song Jo, Improving the power output estimation for a tidal power plant: a case study, Energy, 2023. doi.org/10.1680/jener.23.00007

119-23 Hanif Pourshahbaz, Tadros Ghobrial, Ahmad Shakibaeinia, Evaluating a CFD model for three-dimensional simulation of ice structure interaction, CGU HS Committee on River Ice Processes and the Environment (CRIPE), 22nd Workshop on the Hydraulics of Ice-Covered Rivers, 2023.

118-23 Sruthi T. Kalathil, Venu Chandra, Experimental and numerical investigation on the hydraulic design criteria for a step-pool nature-like fishway, Progress in Physical Geography: Earth and Environment, 2023. doi.org/10.1177/03091333231187619

117-23 Lav Kumar Gupta, Manish Pandey, P. Anand Raj, Numerical simulation of local scour around the pier with and without airfoil collar (AFC) using FLOW-3D, Environmental Fluid Mechanics, 2023. doi.org/10.1007/s10652-023-09932-2

116-23 Paolo Peruzzo, Matteo Cappozzo, Nicola Durighetto, Gianluca Botter, Local processes with a global impact: unraveling the dynamics of gas evasion in a step-and-pool configuration, Biogeosciences, 20; pp. 3261-3271, 2023. doi.org/10.5194/bg-20-3261-2023

114-23 Muhammad Waqas Zaffar, Ishtiaq Hassan, Numerical investigation of hydraulic jump for different stilling basins using FLOW-3D, AQUA – Water Infrastructure, Ecosystems and Society, 72.7; pp. 1320-1343, 2023. doi.org/10.2166/aqua.2023.290

112-23 J. Chandrashekhar Iyer, E.J. James, Indispensability of model studies in the design of settling basins of hydropower projects in river basins with high sediment yield, Fluid Mechanics and Hydraulics, pp. 367-381, 2023. doi.org/10.1007/978-981-19-9151-6_30

110-23 Ehsan Afaridegan, Nosratollah Amanian, Abbas Parsaie, Amin Gharehbaghi, Hydraulic investigation of modified semi-cylindrical weirs, Flow Measurement and Instrumentation, 93; 102405, 2023. doi.org/10.1016/j.flowmeasinst.2023.102405

103-23 Jin Yang, Weqiang Su, Binhua Li, Calculation of natural alluvial separation of sandy tailings slurry based on FLOW-3D, Mechanics in Engineering, 45.3; pp. 559-564, 2023.

101-23 Tutku Ezgi Yönter, Modeling of river flow and flow dynamics near junctions, Thesis, Middle East Technical University, 2023.

99-23 Mohammad Sadeghpour, Mohammad Vaghefi, Seyed Hamed Meraji, Artificial roughness dimensions and their influence on bed topography variations downstream of a culvert: An experimental study, Water Resources Management, 37; pp. 4143-4157, 2023. doi.org/10.1007/s11269-023-03543-8

98-23 M. Aksel, Numerical analysis of the flow structure around inclined solid cylinder and its effect on bed shear stress distribution, Journal of Applied Fluid Mechanics, 16.8; pp. 1627-1639, 2023. doi.org/10.47176/jafm.16.08.1697

96-23 Waqed H. Hassan, Nidaa Ali Shabat, Numerical investigation of the optimum angle for open channel junction, Civil Engineering Journal, 9.5; 2023. doi.org/10.28991/CEJ-2023-09-05-07

94-23 Emad Khanahmadi, Amir Ahmad Dehghani, Seyed Nasrollah Alenabi, Navid Dehghani, Edward Barry, Hydraulic of curved type-B piano key weirs characteristics under free flow conditions, Modeling Earth Systems and Environment, 2023. doi.org/10.1007/s40808-023-01790-7

93-23 Laura-Louise Alicke, Improved priming of a siphon spillway with the use of a flexible membrane researched through numerical modeling, Thesis, Idaho State University, 2023.

91-23 Wahidullah Hakim Safi, Pranab K. Mohapatra, Flow past: An artificial channel confluence with mobile bed, World Environmental and Water Resources Congress, 2023. doi.org/10.1061/9780784484852.023

86-23 Ghasem Aghashirmohammadi, Mohammad Heidarnejad, Mohammad Hossein Purmohammadi, Alireza Masjedi, Experimental and numerical study the effect of flow splitters on trapezoidal and triangular labyrinth weirs, Water Science, 37.1; 2023. doi.org/10.1080/23570008.2023.2210391

84-23 Nikolaos Xafoulis, Evangelia Farsirotou, Spyridon Kotsopoulos, Three-dimensional computational flow dynamics analysis of free-surface flow in a converging channel, Energy Systems, 2023. doi.org/10.1007/s12667-023-00575-2

83-23 Navid Zarrabi, Mohammad Navid Moghim, Mohammad Reza Eftakhar, A semi-analytical study of fiber reinforced concrete abrasion-erosion through water-borne sand-jet flow in hydraulic structures, Tribology International, 185; 108568, 2023. doi.org/10.1016/j.triboint.2023.108568

82-23 Somayyeh Saffar, Abbas Safaei, Farnoush Aghaee Daneshvar, Mohsen Solimani Babarsad, FLOW-3D numerical modeling of converged side weir, Iranian Journal of Science and Technology: Transactions of Civil Engineering, 2023. doi.org/10.1007/s40996-023-01077-y

79-23 Wangshu Wei, Optimization of the mixing in a produced water storage tank using CFD, World Environmental and Water Resources Congress, Eds. Sajjad Ahmad, Regan Murray, 2023. doi.org/10.1061/9780784484852

77-23   Paolo Peruzzo, Matteo Cappozzo, Nicola Durighetto, Gianluca Botter, Local processes with global impact: unraveling the dynamics of gas evasion in a step-and-pool configuration, Biogeosciences, 2023. doi.org/10.5194/bg-2023-68

74-23   Kaywan Othman Ahmed, Nazim Nariman, Dara Muhammad Hawez, Ozgur Kisi, Ata Amini, Predicting and optimizing the influenced parameters for culvert outlet scouring utilizing coupled FLOW 3D-surrogate modeling, Iranian Journal of Science and Technology: Transactions of Civil Engineering, 47; pp. 1763-1776, 2023. doi.org/10.1007/s40996-023-01096-9

73-23   Ashkan Pilbala, Mahmood Shafai Bejestan, Seyed Mohsen Sajjadi, Luigi Fraccarollo, Investigation of the different models of elliptical-Lopac gate performance under submerged flow conditions, Water Resources Management, 2023. doi.org/10.1007/s11269-023-03512-1

69-23   Chonoor Abdi Chooplou, Masoud Ghodsian, Davoud Abediakbar, Aram Ghafouri, An experimental and numerical study on the flow field and scour downstream of rectangular piano key weirs with crest indentations, Innovative Infrastructure Solutions, 8; 140, 2023. doi.org/10.1007/s41062-023-01108-7

68-23   Mahmood Shafai Bajestan, Mostafa Adineh, Hesam Ghodousi, Numerical modeling of sediment washing (flushing) in dams (Case study of Sefidrood dam), Journal of Irrigation Sciences and Engineering, 2023.

65-23   Charles R. Ortloff, CFD investigations of water supply and distribution systems of ancient old and new world archaeological sites to recover ancient water engineering technologies, Water, 15.7; 1363, 2023. doi.org/10.3390/w15071363

63-23   Rasoul Daneshfaraz, Reza Norouzi, Parisa Ebadzadeh, Alban Kuriqi, Effect of geometric shapes of chimney weir on discharge coefficient, Journal of Applied Water Engineering and Research, 2023. doi.org/10.1080/23249676.2023.2192977

59-23   Hongbo Mi, Chuan Wang, Xuanwen Jia, Bo Hu, Hongliang Wang, Hui Wang, Yong Zhu, Hydraulic characteristics of continuous submerged jet impinging on a wall by using numerical simulation and PIV experiment, Sustainability, 15.6; 5159, 2023. doi.org/10.3390/su15065159

58-23   O.P. Maurya, K.K. Nandi, S. Modalavalasa, S. Dutta, Flow hydrodynamics influences due to flood plain sand mining in a meandering channel, Sustainable Environment (NERC 2022), Eds. D. Deka, S.K. Majumder, M.K., Purkait, 2023. doi.org/10.1007/978-981-19-8464-8_16

57-23   Harshvardhan Harshvardhan, Deo Raj Kaushal, CFD modelling of local scour and flow field around isolated and in-line bridge piers using FLOW-3D, EGU General Assembly, EGU23-3820, 2023. doi.org/10.5194/egusphere-egu23-3820

54-23   Reza Nematzadeh, Gholam-Abbas Barani, Ehsan Fadaei-Kermani, Numerical investigation of bed-load changes on sediment flushing cavity, Journal of Hydraulic Structures, 4; 2023. doi.org/10.22055/jhs.2023.42542.1237

53-23   Rasoul Daneshfaraz, Reza Norouzi, Parisa Ebadzadeh, Alban Kuriqi, Influence of sill integration in labyrinth sluice gate hydraulic performance, Innovative Infrastructure Solutions, 8.118; 2023. doi.org/10.1007/s41062-023-01083-z

52-23   Shu Jiang, Yutong Hua, Mengxing He, Ying-Tien Lin, Biyun Sheng, Effect of a circular cylinder on hydrodynamic characteristics over a strongly curved channel, Sustainability, 15.6; 4890, 2023. doi.org/10.3390/su15064890

51-23   Ehsan Aminvash, Kiyoumars Roushangar, Numerical investigation of the effect of the frontal slope of simple and blocky stepped spillway with sem-circular crest on its hydraulic parameters, Iranian Journal of Irrigation and Drainage, 17.1; pp. 102-116, 2023.

50-23   Shizhuang Chen, Anchi Shi, Weiya Xu, Long Yan, Huanling Wang, Lei Tian, Wei-Chau Xie, Numerical investigation of landslide-induced waves: a case study of Wangjiashan landslide in Baihetan Reservoir, China, Bulletin of Engineering Geology and the Environment, 82.110; 2023. doi.org/10.1007/s10064-023-03148-w

49-23   Jiří Procházka, Modelling flow distribution in inlet galleries, VTEI, 1; 2023. doi.org/10.46555/VTEI.2022.11.002

47-23   M. Cihan Aydin, Ali Emre Ulu, Numerical investigation of labyrint