Alignment of a Combined Groin for Flow through a Straight Open Channel
Authors: M. Alauddin, M. A. Ullah, M. Alom, M. N. Islam
The rivers in Bangladesh are highly unstable having loose boundaries, mild slope of water surface and bed, irregular siltation of huge sediment coming from upstream, among others. The groins are installed in the river bank to deflect the flowing water away from the vulnerable zones. The conventional groins are found to be unstable and ineffective. The combined groin having both impermeable and permeable components in the same structure improves the flow field to function better over others. The main goal of this study is to analyze the hydraulic characteristics induced by the combined groins of different alignments by using a 2D numerical model, iRIC Nays2DH. In this numerical simulation, the K-ε model for turbulence and Cubic Interpolation Pseudo-particle (CIP) method for advective terms are utilized. A particular flow condition is applied in the channel for all sets of groins with different alignments. The simulation results reveal that the combined groins alter the flow patterns considerably, with no significant recirculation of flow in the groin field. The effect of different alignments of groins is found somewhat different. Based on hydraulic features caused by the groins, the combined groin that aligns the permeable component towards slightly downstream performs better over others.
Keywords: Combined groin, alignment, hydraulic characteristics, numerical model.Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 174
 W. R. P. Organization, National Water Management Plan, Main Report, Minist. Water Resour., vol. 2, pp. 1–36, 2001.
 M. Rahman, and Y. Muramoto, “Prediction of Maximum Scour Depth Around Spur-Dike-Like Structures,” Proc. Hydraul. Eng., vol. 43, pp. 623–628, 1999.
 T. Ishigaki and Y. Baba, “Local scour induced by 3d flow around attracting and deflecting groins,” Proc. Second Int. Conf. Scour Eros., pp. 301–308, 2004.
 N. Rajaratnam and B. A. Nwachukwu, “Flow Near Groin‐Like Structures,” J. Hydraul. Eng., vol. 109, no. 3, pp. 463–480, 1983.
 W. S. Uijttewaal, “Effects of Groyne Layout on the Flow in Groyne Fields: Laboratory Experiments,” J. Hydraul. Eng., vol. 131, no. 9, 2005.
 J. G. Duan, “Three-dimensional mean flow and turbulence around a spur dike,” World Environmental and Water Resource Congress 2006, pp.1-9, 2007.
 H. Zhang, H. Nakagawa, K. Kawaike, and Y. Baba, “Experiment and simulation of turbulent flow in local scour around a spur dyke,” Int. J. Sediment Res., vol. 24, no. 1, pp. 33–45, 2009.
 W. S. J. Uijttewaal, “The flow in groyne fields: Patterns and exchange processes,” Water Qual. Hazards Dispers. Pollut., pp. 231–246, 2005.
 J. Kang, H. Yeo, S. Kim, and U. Ji, “Permeability effects of single groin on flow characteristics,” J. Hydraul. Res., vol. 49, no. 6, pp. 728–735, 2011.
 M. Alauddin, “Morphological Stabilization of Lowland Rivers by Using a Series of Groynes,” 2011,
[Online]. Available: http://ir.nul.nagoya-u.ac.jp/jspui/handle/2237/16454.
 M. Alauddin, T. Tashiro, and T. Tsujimoto, “Experimental Investigation of Channel Responses Against Different Configurations of Groynes,” vol. 17, pp. 335–340, 2011.
 B. W. Melville, “Local scour at bridge abutments.,” J. Hydraul. Eng., no. 118, pp. 615–63, 1992.
 A. K. Barbhuiya and S. Dey, “Local scour at abutments: A review,” Sadhana - Acad. Proc. Eng. Sci., vol. 29, no. 5, pp. 449–476, 2004.