Numerical investigation of Radius of Curvature on Flow Pattern around a Submerged T-shaped Spur Dike

Document Type : Original Article

Authors

1 M.Sc. Graduate, Civil Engineering Department, Islamic Azad University, Bushehr, Iran

2 M.Sc. Student of Hydraulic Structures, Department of Civil Engineering, Persian Gulf University, Bushehr, Iran;

Abstract

Spur dike is one of the various hydraulic structures used in rivers, and are utilized in order to protect river banks, keeping the flow away from the walls, and directing them towards the main route. Due to flow digression, a turbulent circulation zone appears around the spur dike. Consequently, in order to prevent local scour, they use a wider, T-shaped nose for the spur dike. In this paper, a study on flow pattern around a 25 percent submerged T-shaped spur dike, located in a 45 degree position, in a 90 degree bend with rigid bed, and various relative radius of curvature 2, 3, 4, and 5, with a constant discharge of 25 lit/s has been conducted using Flow-3D software. Numerical results have been compared with experimental results, and they have been analyzed. The results indicate that with an increase in radius of curvature, the number of vortexes in cross sections near the wing of the spur dike, as well as lateral velocity of the flow increases, and the maximum lateral velocity is found upstream of the wing of the T-shaped spur dike. It was also observed that the less the relative radius of curvature is, the wider zone downstream of the spur dike has relative immobility of the flow.

Keywords

References

صفرزاده گندشمین، ا. 1383. مدل‌سازی عددی جریان ثانویه در قوس رودخانه. سمینار کارشناسی ارشد، دانشکده فنی و مهندسی، دانشگاه تربیت مدرس.
واقفی، م. و م. قدسیان. 1389. مطالعه آزمایشگاهی الگوی جریان پیرامون آبشکن T شکل در قوس 90 درجه با بستر متحرک. نشریه مهندسی عمران و نقشه‌برداری دانشکده فنی دانشگاه تهران، دوره 44، شماره 2، ص 276-265.
واقفی، م.، م. قدسیان و س. ع. ا. صالحی نیشابوری. 1387. بررسی آزمایشگاهی الگوی جریان کمی اطراف آبشکن T شکل در قوس 90 درجه با بستر صلب. مجله علمی-پژوهشی دانشگاه تبریز، جلد 37، شماره 3، ص81-87.
واقفی، م.، م. قدسیان و س. ع. ا. صالحی نیشابوری. 1388. بررسی آزمایشگاهی اثر شعاع انحنا و موقعیت استقرار آبشکن های T شکل در قوس 90 درجه  بر میزان آبشستگی اطراف آن‌ها. مجله علمی-پژوهشی هیدرولیک ایران، دوره 4، شماره 1، ص 91-107.
Acharya, A., A. Acharya and J. G. Duan. 2011. Three Dimensional Simulation of Flow Field around Series of Spur Dikes. International Refereed Journal of Engineering and Science (IRJES), 2(7): 36-57.
Ahmad, M. 1951. Spacing and protection of spurs for bank protection. Civil Engineering and Publication review, 46(1): 3-7.
Ahmad, M. 1951. Experiments on Design and Behavior of Spur dikes. Proc. Of Cong. Of IAHR: 145-159.
Duan, J. G., L. He, X. Fu and Q. Wang. 2009. Mean flow and turbulence around experimental spur dike. Advances in Water Resources, 32(12): 1717-1725.
Fazli, M., M. Ghodsian and S. A. A. Salehi Neyshaboori. 2008. Scour and Flow Field around a Spur Dike in 90Degree Bend. International Journal of Sediment Research, 23: 56-68.
Flow Science, Inc. 2008. Flow-3D User’s Manual, 9.3 editions.
Ghodsian, M. and M. Vaghefi. 2009. Experimental study on scour and flow field in a scour hole around a T shape spur dike in a 90 degree bend. Journal of Sediment Research, 24(2):145-158.
Giri, S., Y. Shimizu and B. Surajata. 2004. Laboratory Measurement and Numerical Simulation of Flow and Turbulence in a Meandering-Like Flume with Spurs. Flow Measurement and Instrumentation, 15: 301-309.
Nagata, N., T. Hosda and T. Nakato. 2005. Three-Dimensional Numerical Model for Flow and Bed Deformation around River Hydraulic Structures. Journal of Hydraulic Engineering, ASCE, 131(12): 1074-1087.
Naji Abhari, M. N., M. Ghodsian, M. Vaghefi and N. Panahpur. 2010. Experimental and numerical simulation of flow in a 90 bend, Flow Measurement and Instrumentation, 21(3): 292-298.
Soliman, M. M., K. M. Attia, Kotb, A. M. Talaat and A. F. Ahmed. 1997. Spur Dike Effects on the River Nile Morphology after High Aswan Dam. Congress of the International Association of Hydraulic Research, IAHR, 120(9): 125-146.
Tingsanchali, T. and S. Maheswaran. 1990. 2-D Depth-Averaged Flow Computation near Groin. Journal of Hydraulic. Engineering, ASCE, 116(1): 71-86.
Vaghefi, M., M. Godsian and S.A.A. Salehi Neyshaboori. 2009. Experimental Study on the Effect of a T-Shaped Spur Dike Length on Scour in a 90 degree channel bend. The Arabian Journal for Science and Engineering, 34(2B): 337-348.
Vaghefi, M., M. Godsian and S.A.A. Salehi Neyshaboori. 2012. Experimental Study on Scour around a T-Shaped Spur Dike in a Channel Bend. Journal of Hydraulic Engineering, Vol. 138, No.5, pp. 471-474.
Vaghefi, M., M. Ghodsian and A. Adib. 2012. Experimental Study on the Effect of Froude Number on Temporal Variation of Scour around a T-shaped Spur Dike in a 90 Degree Bend. Applied Mechanics and Materials, 147: 75-79.
Yazdi, J., H. Sarkardeh, H. M. Azamathulla and A. A. Ghani. 2010. 3D simulation of flow around a single spur dike with free-surface flow. International Journal of River Basin Management, 8(1): 55-62.
 

Files

Share

How to cite

Statistics