Figure 5 - Modeling a simple lotus overflow symmetrically in FLOW-3D software

Effect of Vortex Breaker Blades 45 Degree on Discharge Coefficient of Morning Glory Spillway Using Flow-3D

Authors

S. Noruzi1
and J. Ahadiyan2*
1– M.Sc. Student, Faculty of Water Sciences Engineering, Shahid Chamran University of Ahvaz, Iran.
2*-Corresponding Author, Associate Professor, Faculty of Water Sciences Engineering, Shahid Chamran
University of Ahvaz, Iran.

Abstract

The discharge coefficient of morning glory spillway is decreased with eddies created by vortex at the inlet part of weir. However, a series of specific blades can reduce vortices which result in the spillway efficiency is increased. Hence, in this research numerical modeling of installed breaker blade on morning glory spillway was evaluated using Flow-3D model. To achieve these purposes, morning glory spillway was modeled without and with blades 3, 4 and 6 blades at 45 degree angle. To simulate the turbulence fluctuations, the modified k-e model (RNG k-e) was used and its results were compared to the experimental data. Results showed that by installing blades, the discharge coefficient increases up to 42 percent with 25 percent decreasing in the upstream water level. Moreover, among the three different arrangements of blades, the six-blade model was found to have more satisfactory results than other models. In comparison to control model, for H/D between 0 to 0.1 and 0.1 to 0.2 the discharge coefficient has been increased 40 and 57 percent for six-blade arrangement, respectively. 

모닝 글로리의 배출 계수는 위어 입구 부분의 와류에 의해 생성된 소용돌이로 감소합니다. 그러나 일련의 특정 블레이드는 와류를 줄여 배수로 효율성을 높일 수 있습니다. 따라서 본 연구에서는 모닝 글로리 여수로에 설치된 브레이커 블레이드의 수치 모델링을 Flow-3D 모델을 사용하여 평가했습니다. 이러한 목적을 달성하기 위해 45도 각도에서 블레이드 3, 4 및 6 블레이드 없이 모닝 글로리 여수로를 모델링 했습니다. 난류 변동을 시뮬레이션하기 위해 수정된 k-e 모델 (RNG k-e)을 사용하고 그 결과를 실험 데이터와 비교했습니다. 결과에 따르면 블레이드를 설치하면 상류 수위가 25 % 감소하면서 배출 계수가 42 %까지 증가합니다. 또한 3 개의 블레이드 배열 중 6 개 블레이드 모델이 다른 모델보다 더 만족스러운 결과를 나타냈다. 제어 모델에 비해 H / D가 0 ~ 0.1 및 0.1 ~ 0.2 인 경우 방전 계수가 6- 블레이드 배열에서 각각 40 % 및 57 % 증가했습니다.

Keywords

Figure 1 - Dimensions of the vortex blade
Figure 1 – Dimensions of the vortex blade
Figure 3 - A (Physical model of lotus overflow without blade, b) Physical model of lotus overflow with eddy blades.
Figure 3 – A (Physical model of lotus overflow without blade, b) Physical model of lotus overflow with eddy blades.
Figure 5 - Modeling a simple lotus overflow symmetrically in FLOW-3D software
Figure 5 – Modeling a simple lotus overflow symmetrically in FLOW-3D software
Figure 7 - Comparison of Ashley flow chart with numerical model and laboratory
Figure 7 – Comparison of Ashley flow chart with numerical model and laboratory
Figure 8 - Comparison of flow coefficient diagram - immersion ratio of numerical model with laboratory: a (overflow without blade, b) overflow with three blades, c (overflow with four blades, d) overflow with six blades
Figure 8 – Comparison of flow coefficient diagram – immersion ratio of numerical model with laboratory: a (overflow without blade, b) overflow with three blades, c (overflow with four blades, d) overflow with six blades

Reference

1 -حیدری ارجلو، س.، موسوی جهرمی، س. ح. و ادیب، ا. 1386 .بررسی تاثیر شیب بر تعداد بهینه پلکانها در سرریزهای پلکانی، مجله علوم و مهندسی
.)123-136 :)2(33 ،كشاورزی علمی )آبیاری
2 -حاجیپور، گ. 1363 .بررسی آزمایشگاهی تأثیر تیغههای گردابشکن بر هیدرولیک جریان سرریز نیلوفری. پایاننامه كارشناسی ارشد رشته سازههای آبی،
دانشکده مهندسی علوم آب، دانشگاه شهید چمران اهواز.
3 -رنجبر ملکشاه، م.، 1363 .بررسی رفتار سرریز نیلوفری با پایین دست تاج پلکانی بوسیله مدلسازی رایانهای، پایاننامه كارشناسی ارشد مهندسی عمران،
دانشکده مهندسی عمران، دانشگاه خواجه نصیر طوسی.
4 -رمضانی، س. كاویانپور، م ر. و ع. حسنی نژاد. 1362 .بررسی پارامترهای مؤثر بر آبگذری سرریزهای نیلوفری. هفتمین كنگره ملی مهندسی عمران،
دانشکده مهندسی شهید نیکبخت، زاهدان.
1 -سامانی، م. 1331 .طراحی سازههای هیدرولیکی. انتشارات شركت مهندسی مشاور دز آب اهواز
1 -قاسمزاده، ف. 1362 .شبیه سازی مسائل هیدرولیکی در 3D-FLOW .تهران، نوآور.
3 -كمانبدست، 1 ،.موسوی، س.ر. 1361 .مطالعه آزمایشگاهی تأثیر تعداد و زاویه گرداب شکن بر مشخصات جریان در سرریز نیلوفری مربعی، نشریه علوم
آب و خاک )غعلوم و فنون كشاورزی و منابع طبیعی(، سال بیستم، شماره 38 ،صفحه 182-131 .
8 -نظری پوركیانی، ع ا. 1363 .بررسی فشار و سرعت جریان در سرریز نیلوفری سد البرز با استفاده از نرمافزار 3D-FLOW .اولین كنفرانس سراسری
توسعه محوری مهندسی عمران، معماری، برق و مکانیک ایران.
6 -نوحانی، ا.، جمالی امام قیس، ر. 1364 .بررسی آزمایشگاهی تأثیرشکل تیغه های ضد گرداب برراندمان تخلیهی سرریزهای نیلوفری، نشریه آبیاری و
زهکشی ایران، جلد 6 ،شماره 1 ،صفحه 346-341 .
10-Akbari, A A., Nohani, E and A. Afrous. 2015. Numerical study of the effect of anti-vortex plates on the
inflow pattern in shaft spillways. Indian Journal of Fundamental and Applied Life Sciences, 5(S1):
3819-3826.
11-Anonymous, 1965. Design of Small Dams. Water Resources Technical publication, U.S Department of
the interior Bureau of Reclamation.
12-Bagheri, A., Shafai Bajestan, M., Mousavi Jahromi, H., Kashkuli, H. and H. Sedghi. 2010. Hydraulic
evaluation of the flow over polyhedral morning glory spillways. Word Applied Sciences Journal, 9(7):
712-717.
13- Fattor, C. A. and J. D. Bacchiega. 2003. Analysis of instabilities in the charge of regime in morning
glory spillways. Journal of Hydraulic Research, 40(4): 114-123.
14- Khatsuria, R. M. 2005. Hydraulics of spillways and energy dissipaters. Marcel Dekker. Department of
Civil and Environmental Engineering Georgia, Institute of Technology Atlanta, Newyork, USA.
15-Mousavi. S. R., Kamanbedast, A.A., and H. Fathian. 2013. Experimental investigation of the effect of
number of anti-vortex piers on submergence threshold in morning glory spillway with square inlet.
Technical Journal of Engineering and Applied Sciences, 3(24): 3534-3540.
16- Novak, P. 2007. Hydraulic Structures, Fourth edition published by Taylor and Francis. University of
New Castle upon, Tyne, UK, Landon and Network.
17-Tavana, M H., Mousavi Jahromi, H., Shafai Bajestan, M., Masjedi, A. R. and H. Sedghi. 2011.
Optimization of number and direction of vortex breakers in the morning glory spillway using physical
model. Economy, Environmental and Conservation Journal, 17(2): 435-440.
18-Vresteeg. H. K and W. Malalasekera. 1995. An introduction to computational fluid dynamics. Longman
Scientific and Technical. New York.
19-Yakhot. V and L. M. Smith. 1992. The renormalization group. The e-expansion and of turbulence
models. Journal of Computing, 7(1): 35-61.