Numerical Investigation of Flow and Scour Pattern around T-shaped Spur Dike in a 90 Degree Bend with Live Bed

Document Type : Technical Note

Authors

1 Assistant Professor of Hydraulic Structures, Department of Civil Engineering, Persian Gulf University, Bushehr, Iran

2 MSc., Civil Engineering Department, Persian Gulf University, Bushehr, Iran.

3 Assistant Professor, Department of Civil Engineering, Persian Gulf University, Bushehr, Iran

Abstract

In this paper, numerical investigation of flow and scour pattern around T-shaped spur dike located in a 90 degree bend with live bed was carried out using SSIIM software. The channel under investigation was a 90 degree channel with radius of curvature of 2.4 meters, and a T-shaped spur dike was located in a 45 degree position in proportion to the outer bank for determination of flow pattern, with the ratio of wing to web equal to 1. For determination of scour pattern, the ratio of wing to web was considered to range from 0.25 to 1.25. Comparison between the results of experimental data and numerical modeling using SSIIM software indicated good agreement between the two. Changes in lateral velocity, profile of the bed due to the effect of the ratio of the wing to the web of the spur dike,    3D velocity components as well as changes in the maximum scour depth were also compared.  The results indicated that the amount of scour was minimum for the ratio of wing to web equal to 1.25. Changes in the maximum scour depth occurred in the range of 1.29 to 1.42 times the upstream depth. It was also observed that two vortexes were formed at the downstream side of the spur dike, one clockwise and the other counterclockwise

Keywords

References

معاونت برنامه‌ریزی و نظارت راهبردی رییس‌جمهور (1388). "راهنمای طراحی، ساخت و نگه‌داری آبشکن‌های رودخانه‌ای"، نشریه شماره 516.
واقفی م.، قدسیان م. و صالحی نیشابوری ع. (1387). "مطالعه آزمایشگاهی الگوی جریان سه بعدی و آبشستگی در قوس 90 درجه"، مجله علمی و پژوهشی هیدرولیک ایران، دوره 3، شماره 3، ص.ص. 41-57.
واقفی م.، قدسیان م. و صالحی نیشابوری ع. (1388). "بررسی آزمایشگاهی اثر شعاع انحنا و موقعیت استقرار آبشکن‌های T شکل در قوس 90 درجه بر میزان آبشستگی اطراف آنها"، مجله علمی و پژوهشی هیدرولیک ایران، دوره چهارم، شماره 1، ص.ص. 91-107.
واقفی م. و قدسیان م. (1389). "تأثیر استقرار آبشکن T شکل بر توپوگرافی پایین‌دست بستر قوس 90 درجه"، مجله علمی و پژوهشی دانشگاه فردوسی مشهد، سال بیست و دوم، شماره 1، ص.ص. 128-113.
Ettema R. and Muste M. (2004). "Scale effect in flume experiments on flow around a spur dike in flat bed channel", Journal of Hydraulic Engineering. Vol. 130, No. 7, pp. 635-646.
Giri S., Shimizu Y. and Surajata B. (2004). "Laboratory measurement and numerical simulation of flow and turbulence in a meandering-like flume with spurs". Flow Measurement and Instrumentation. No. 15, pp. 301-309.
 
Ghodsian M. and Vaghefi M. )2009). "Experimental study on scour and flow field in scour hole around a T shaped spur dike in a 90° bend", International Journal of Sediment Research. Vol. 24, No. 2, pp. 145-158.
NajiAbhari M., Ghodsian M., Vaghefi M. and Panahpur N. (2010). "Experimental and numerical simulation of flow in a 90 bend", Flow Measurement and Instrumentation, Vol. 21, No. 3, pp. 292-298.
Olsen N, R, B (2004). "A three dimensional numerical model for simulation movement in water intakes with multi block option", Department of Hydraulic and Environmental Engineering, The Norwegian University of Science and Technology.
Vaghefi M., Ghodsian M. and Salehi Neyshabouri S.A.A. (2009). "Experimental study on the effect of a T shaped spur dike length on scour in a 90o channel", The Arabian Journal for Science and Engineering.Vol. 34, No. 2B, pp. 337-348.
Vaghefi M., Ghodsian M. and Salehi Neyshabouri S.A.A. (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.

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History

  • Receive Date: 22 October 2014
  • Accept Date: 22 October 2014

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