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

무작위 파동에서 우산 흡입 앵커 기초 주변의 세굴 특성 및 평형 세굴 깊이 예측

Ruigeng Hu 1
, Hongjun Liu 2
, Hao Leng 1
, Peng Yu 3 and Xiuhai Wang 1,2,*

1 College of Environmental Science and Engineering, Ocean University of China, Qingdao 266000, China;
huruigeng@stu.ouc.edu.cn (R.H.); lh4517@stu.ouc.edu.cn (H.L.)
2 Key Lab of Marine Environment and Ecology (Ocean University of China), Ministry of Education,
Qingdao 266000, China; hongjun@ouc.edu.cn
3 Qingdao Geo-Engineering Survering Institute, Qingdao 266100, China; yp6650@stu.ouc.edu.cn

Abstract

무작위 파동 하에서 우산 흡입 앵커 기초(USAF) 주변의 국부 세굴을 연구하기 위해 일련의 수치 시뮬레이션이 수행되었습니다. 본 연구에서는 먼저 본 모델의 정확성을 검증하기 위해 검증을 수행하였다.

또한, 세굴 진화와 세굴 메커니즘을 각각 분석하였다. 또한 USAF 주변의 평형 세굴 깊이 Seq를 예측하기 위해 두 가지 수정된 모델이 제안되었습니다. 마지막으로 Seq에 대한 Froude 수 Fr과 Euler 수 Eu의 영향을 연구하기 위해 매개변수 연구가 수행되었습니다.

결과는 현재 수치 모델이 무작위 파동에서 세굴 형태를 묘사하는 데 정확하고 합리적임을 나타냅니다.

수정된 Raaijmaker의 모델은 KCs,p < 8일 때 본 연구의 시뮬레이션 결과와 잘 일치함을 보여줍니다. 수정된 확률적 모델의 예측 결과는 KCrms,a < 4일 때 n = 10일 때 가장 유리합니다. Fr과 Eu가 높을수록 둘 다 더 집중적 인 말굽 소용돌이와 더 큰 결과를 초래합니다.

Figure 1. The close-up of umbrella suction anchor foundation (USAF).
Figure 1. The close-up of umbrella suction anchor foundation (USAF).
Figure 2. (a) The sketch of seabed-USAF-wave three-dimensional model; (b) boundary condation:Wvwave boundary, S-symmetric boundary, O-outflow boundary; (c) USAF model.
Figure 2. (a) The sketch of seabed-USAF-wave three-dimensional model; (b) boundary condation:Wvwave boundary, S-symmetric boundary, O-outflow boundary; (c) USAF model.
Figure 5. Comparison of time evolution of scour between the present study and Khosronejad et al. [52], Petersen et al. [17].
Figure 5. Comparison of time evolution of scour between the present study and Khosronejad et al. [52], Petersen et al. [17].
Figure 9. Scour morphology under different times for case 7.
Figure 9. Scour morphology under different times for case 7.

References

  1. Sumer, B.M.; Fredsøe, J.; Christiansen, N. Scour Around Vertical Pile in Waves. J. Waterw. Port. Coast. Ocean Eng. 1992, 118, 15–31.
    [CrossRef]
  2. Rudolph, D.; Bos, K. Scour around a monopile under combined wave-current conditions and low KC-numbers. In Proceedings of
    the 6th International Conference on Scour and Erosion, Amsterdam, The Netherlands, 1–3 November 2006; pp. 582–588.
  3. Nielsen, A.W.; Liu, X.; Sumer, B.M.; Fredsøe, J. Flow and bed shear stresses in scour protections around a pile in a current. Coast.
    Eng. 2013, 72, 20–38. [CrossRef]
  4. Ahmad, N.; Bihs, H.; Myrhaug, D.; Kamath, A.; Arntsen, Ø.A. Three-dimensional numerical modelling of wave-induced scour
    around piles in a side-by-side arrangement. Coast. Eng. 2018, 138, 132–151. [CrossRef]
  5. Li, H.; Ong, M.C.; Leira, B.J.; Myrhaug, D. Effects of Soil Profile Variation and Scour on Structural Response of an Offshore
    Monopile Wind Turbine. J. Offshore Mech. Arct. Eng. 2018, 140, 042001. [CrossRef]
  6. Li, H.; Liu, H.; Liu, S. Dynamic analysis of umbrella suction anchor foundation embedded in seabed for offshore wind turbines.
    Géoméch. Energy Environ. 2017, 10, 12–20. [CrossRef]
  7. Fazeres-Ferradosa, T.; Rosa-Santos, P.; Taveira-Pinto, F.; Vanem, E.; Carvalho, H.; Correia, J.A.F.D.O. Editorial: Advanced research
    on offshore structures and foundation design: Part 1. Proc. Inst. Civ. Eng. Marit. Eng. 2019, 172, 118–123. [CrossRef]
  8. Chavez, C.E.A.; Stratigaki, V.; Wu, M.; Troch, P.; Schendel, A.; Welzel, M.; Villanueva, R.; Schlurmann, T.; De Vos, L.; Kisacik,
    D.; et al. Large-Scale Experiments to Improve Monopile Scour Protection Design Adapted to Climate Change—The PROTEUS
    Project. Energies 2019, 12, 1709. [CrossRef]
  9. Wu, M.; De Vos, L.; Chavez, C.E.A.; Stratigaki, V.; Fazeres-Ferradosa, T.; Rosa-Santos, P.; Taveira-Pinto, F.; Troch, P. Large Scale
    Experimental Study of the Scour Protection Damage Around a Monopile Foundation Under Combined Wave and Current
    Conditions. J. Mar. Sci. Eng. 2020, 8, 417. [CrossRef]
  10. Sørensen, S.P.H.; Ibsen, L.B. Assessment of foundation design for offshore monopiles unprotected against scour. Ocean Eng. 2013,
    63, 17–25. [CrossRef]
  11. Prendergast, L.; Gavin, K.; Doherty, P. An investigation into the effect of scour on the natural frequency of an offshore wind
    turbine. Ocean Eng. 2015, 101, 1–11. [CrossRef]
  12. Fazeres-Ferradosa, T.; Chambel, J.; Taveira-Pinto, F.; Rosa-Santos, P.; Taveira-Pinto, F.; Giannini, G.; Haerens, P. Scour Protections
    for Offshore Foundations of Marine Energy Harvesting Technologies: A Review. J. Mar. Sci. Eng. 2021, 9, 297. [CrossRef]
  13. Yang, Q.; Yu, P.; Liu, Y.; Liu, H.; Zhang, P.; Wang, Q. Scour characteristics of an offshore umbrella suction anchor foundation
    under the combined actions of waves and currents. Ocean Eng. 2020, 202, 106701. [CrossRef]
  14. Yu, P.; Hu, R.; Yang, J.; Liu, H. Numerical investigation of local scour around USAF with different hydraulic conditions under
    currents and waves. Ocean Eng. 2020, 213, 107696. [CrossRef]
  15. Sumer, B.M.; Christiansen, N.; Fredsøe, J. The horseshoe vortex and vortex shedding around a vertical wall-mounted cylinder
    exposed to waves. J. Fluid Mech. 1997, 332, 41–70. [CrossRef]
  16. Sumer, B.M.; Fredsøe, J. Scour around Pile in Combined Waves and Current. J. Hydraul. Eng. 2001, 127, 403–411. [CrossRef]
  17. Petersen, T.U.; Sumer, B.M.; Fredsøe, J. Time scale of scour around a pile in combined waves and current. In Proceedings of the
    6th International Conference on Scour and Erosion, Paris, France, 27–31 August 2012.
  18. Petersen, T.U.; Sumer, B.M.; Fredsøe, J.; Raaijmakers, T.C.; Schouten, J.-J. Edge scour at scour protections around piles in the
    marine environment—Laboratory and field investigation. Coast. Eng. 2015, 106, 42–72. [CrossRef]
  19. Qi, W.; Gao, F. Equilibrium scour depth at offshore monopile foundation in combined waves and current. Sci. China Ser. E Technol.
    Sci. 2014, 57, 1030–1039. [CrossRef]
  20. Larsen, B.E.; Fuhrman, D.R.; Baykal, C.; Sumer, B.M. Tsunami-induced scour around monopile foundations. Coast. Eng. 2017, 129,
    36–49. [CrossRef]
  21. Corvaro, S.; Marini, F.; Mancinelli, A.; Lorenzoni, C.; Brocchini, M. Hydro- and Morpho-dynamics Induced by a Vertical Slender
    Pile under Regular and Random Waves. J. Waterw. Port. Coast. Ocean Eng. 2018, 144, 04018018. [CrossRef]
  22. Schendel, A.; Welzel, M.; Schlurmann, T.; Hsu, T.-W. Scour around a monopile induced by directionally spread irregular waves in
    combination with oblique currents. Coast. Eng. 2020, 161, 103751. [CrossRef]
  23. Fazeres-Ferradosa, T.; Taveira-Pinto, F.; Romão, X.; Reis, M.; das Neves, L. Reliability assessment of offshore dynamic scour
    protections using copulas. Wind. Eng. 2018, 43, 506–538. [CrossRef]
  24. Fazeres-Ferradosa, T.; Welzel, M.; Schendel, A.; Baelus, L.; Santos, P.R.; Pinto, F.T. Extended characterization of damage in rubble
    mound scour protections. Coast. Eng. 2020, 158, 103671. [CrossRef]
  25. Tavouktsoglou, N.S.; Harris, J.M.; Simons, R.R.; Whitehouse, R.J.S. Equilibrium Scour-Depth Prediction around Cylindrical
    Structures. J. Waterw. Port. Coast. Ocean Eng. 2017, 143, 04017017. [CrossRef]
  26. Ettema, R.; Melville, B.; Barkdoll, B. Scale Effect in Pier-Scour Experiments. J. Hydraul. Eng. 1998, 124, 639–642. [CrossRef]
  27. Umeda, S. Scour Regime and Scour Depth around a Pile in Waves. J. Coast. Res. Spec. Issue 2011, 64, 845–849.
  28. Umeda, S. Scour process around monopiles during various phases of sea storms. J. Coast. Res. 2013, 165, 1599–1604. [CrossRef]
  29. Baykal, C.; Sumer, B.; Fuhrman, D.R.; Jacobsen, N.; Fredsøe, J. Numerical simulation of scour and backfilling processes around a
    circular pile in waves. Coast. Eng. 2017, 122, 87–107. [CrossRef]
  30. Miles, J.; Martin, T.; Goddard, L. Current and wave effects around windfarm monopile foundations. Coast. Eng. 2017, 121,
    167–178. [CrossRef]
  1. Miozzi, M.; Corvaro, S.; Pereira, F.A.; Brocchini, M. Wave-induced morphodynamics and sediment transport around a slender
    vertical cylinder. Adv. Water Resour. 2019, 129, 263–280. [CrossRef]
  2. Yu, T.; Zhang, Y.; Zhang, S.; Shi, Z.; Chen, X.; Xu, Y.; Tang, Y. Experimental study on scour around a composite bucket foundation
    due to waves and current. Ocean Eng. 2019, 189, 106302. [CrossRef]
  3. Carreiras, J.; Larroudé, P.; Seabra-Santos, F.; Mory, M. Wave Scour Around Piles. In Proceedings of the Coastal Engineering 2000,
    American Society of Civil Engineers (ASCE), Sydney, Australia, 16–21 July 2000; pp. 1860–1870.
  4. Raaijmakers, T.; Rudolph, D. Time-dependent scour development under combined current and waves conditions—Laboratory
    experiments with online monitoring technique. In Proceedings of the 4th International Conference on Scour and Erosion, Tokyo,
    Japan, 5–7 November 2008; pp. 152–161.
  5. Khalfin, I.S. Modeling and calculation of bed score around large-diameter vertical cylinder under wave action. Water Resour. 2007,
    34, 357. [CrossRef]
  6. Zanke, U.C.; Hsu, T.-W.; Roland, A.; Link, O.; Diab, R. Equilibrium scour depths around piles in noncohesive sediments under
    currents and waves. Coast. Eng. 2011, 58, 986–991. [CrossRef]
  7. Myrhaug, D.; Rue, H. Scour below pipelines and around vertical piles in random waves. Coast. Eng. 2003, 48, 227–242. [CrossRef]
  8. Myrhaug, D.; Ong, M.C.; Føien, H.; Gjengedal, C.; Leira, B.J. Scour below pipelines and around vertical piles due to second-order
    random waves plus a current. Ocean Eng. 2009, 36, 605–616. [CrossRef]
  9. Myrhaug, D.; Ong, M.C. Random wave-induced onshore scour characteristics around submerged breakwaters using a stochastic
    method. Ocean Eng. 2010, 37, 1233–1238. [CrossRef]
  10. Ong, M.C.; Myrhaug, D.; Hesten, P. Scour around vertical piles due to long-crested and short-crested nonlinear random waves
    plus a current. Coast. Eng. 2013, 73, 106–114. [CrossRef]
  11. Yakhot, V.; Orszag, S.A. Renormalization group analysis of turbulence. I. Basic theory. J. Sci. Comput. 1986, 1, 3–51. [CrossRef]
  12. Yakhot, V.; Smith, L.M. The renormalization group, the e-expansion and derivation of turbulence models. J. Sci. Comput. 1992, 7,
    35–61. [CrossRef]
  13. Mastbergen, D.R.; Berg, J.V.D. Breaching in fine sands and the generation of sustained turbidity currents in submarine canyons.
    Sedimentology 2003, 50, 625–637. [CrossRef]
  14. Soulsby, R. Dynamics of Marine Sands; Thomas Telford Ltd.: London, UK, 1998. [CrossRef]
  15. Van Rijn, L.C. Sediment Transport, Part I: Bed Load Transport. J. Hydraul. Eng. 1984, 110, 1431–1456. [CrossRef]
  16. Zhang, Q.; Zhou, X.-L.; Wang, J.-H. Numerical investigation of local scour around three adjacent piles with different arrangements
    under current. Ocean Eng. 2017, 142, 625–638. [CrossRef]
  17. Yu, Y.X.; Liu, S.X. Random Wave and Its Applications to Engineering, 4th ed.; Dalian University of Technology Press: Dalian,
    China, 2011.
  18. Pang, A.; Skote, M.; Lim, S.; Gullman-Strand, J.; Morgan, N. A numerical approach for determining equilibrium scour depth
    around a mono-pile due to steady currents. Appl. Ocean Res. 2016, 57, 114–124. [CrossRef]
  19. Higuera, P.; Lara, J.L.; Losada, I.J. Three-dimensional interaction of waves and porous coastal structures using Open-FOAM®.
    Part I: Formulation and validation. Coast. Eng. 2014, 83, 243–258. [CrossRef]
  20. Corvaro, S.; Crivellini, A.; Marini, F.; Cimarelli, A.; Capitanelli, L.; Mancinelli, A. Experimental and Numerical Analysis of the
    Hydrodynamics around a Vertical Cylinder in Waves. J. Mar. Sci. Eng. 2019, 7, 453. [CrossRef]
  21. Flow3D User Manual, version 11.0.3; Flow Science, Inc.: Santa Fe, NM, USA, 2013.
  22. Khosronejad, A.; Kang, S.; Sotiropoulos, F. Experimental and computational investigation of local scour around bridge piers. Adv.
    Water Resour. 2012, 37, 73–85. [CrossRef]
  23. Stahlmann, A. Experimental and Numerical Modeling of Scour at Foundation Structures for Offshore Wind Turbines. Ph.D. Thesis,
    Franzius-Institute for Hydraulic, Estuarine and Coastal Engineering, Leibniz Universität Hannover, Hannover, Germany, 2013.
  24. Breusers, H.N.C.; Nicollet, G.; Shen, H. Local Scour Around Cylindrical Piers. J. Hydraul. Res. 1977, 15, 211–252. [CrossRef]
  25. Schendel, A.; Hildebrandt, A.; Goseberg, N.; Schlurmann, T. Processes and evolution of scour around a monopile induced by
    tidal currents. Coast. Eng. 2018, 139, 65–84. [CrossRef]
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