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Abstract

 In this paper, the bed topography of a channel at a 90-degree bend was studied at the T-shaped spur dike installed at the middle of the outer bank. Numerical analyses were performed with the Sediment Simulation in Intakes with Multiblock Option (SSIIM) model. Three relative curvatures (R/B =  2, 3, and 4) related to the three sediment densities (P  = 2.35, 2.5, and 2.65) were modeled in nine cases and the effects of sediment density on the bed scour patterns were studied. It was observed that the maximum amount of scour occurred near the head of the dike wing at the dike’s upstream, and the maximum amount of sedimentation occurred at the inner bank of the bend exit. By increasing the sediment density when R/B  = 4, the maximum scour and sedimentation decreased to 27.41% and 46.15%, respectively. When R/B  = 3, the maximum scour and sedimentation decreased to 25.93% and 23.91%, respectively. When R/B  = 2, the maximum scour and sedimentation decreased to 25.98% and 10%, respectively.

 

Keywords

SSIIM model T-shaped spur dike channel bend Sediment density Relative curvature.

Article Details

How to Cite
Vaghefi, M., Safarpoor, Y., & Hashemi, S. (2016). Effect of Sediment Density on the Bed Topography in a Channel Bend Using Numerical Modeling. The Journal of Engineering Research [TJER], 13(1), 22–32. https://doi.org/10.24200/tjer.vol13iss1pp22-32

References

  1. Abhari M, Ghodsian M, Vaghefi M, Panahpur N (2010), Experimental and numerical simulation of flow in a 90 degree of bend. Flow Measurement and Instrumentation 21: 292–298
  2. Azinfar H (2010), Flow resistance and associated backwater effect due to spur dikes in open channels. A thesis submitted to for the degree of Doctor of Philosophy, Department of Civil and Geological Engineering, University of Saskatchewan Saskatoon, Canada.
  3. Booij R (2002) Modeling of the secondary flow structure in river bends. In, River Flow, Bousmar and Zech (Eds), ISBN 90 5809 509 6: 127:133.
  4. Da Silva AMF, Yalin MS (1997), Laboratory measurements in sine-generated meandering channels. International Journal of Sediment Research 12(1): 16–28.
  5. Elawady E, Michiue M, Hinokidani O (2001), Movable bed scour around submerged spurdikes. Annual Journal of Hydraulic Engineering 45: 373–378.
  6. Ghodsian M, Vaghefi M (2009), Experimental study on scour and flow field in a scour hole around a T-shape spur dike in a 90° bend. International Journal of Sediment Research 24: 145– 158.
  7. Gill MA (1972) Erosion of sand beds around spur dikes. Journal of the Hydraulics Division 98(9): 91– 98.
  8. Hua L, Roger A, Kuhnle B, Barkdoll D (2006), Countermeasures against scour at abutments. Research Report No.49, Channel and Watershed Processes Research Unit, National Sedimentation Laboratory, USDA Agricultural Research Service Oxford.
  9. Lian HC, Hsied TY, Yang JC (1999), Bend-flow simulation using 2d depth–averaged mode. Journal of Hydraulic Engineering 125(10): 1097–1108.
  10. Nouh MA, Townsend RD (1979), Shear-stress distribution in stable channel bends. Journal of the Hydraulics Division, American Society of Civil Engineers 105 (HY10) Proceedings Paper 14898, 1233–1245.
  11. Olsen NRB (1999), Computational fluid dynamics in hydraulic and sedimentation engineering. Department of Hydraulic and environmental Engineering, Norwegian University of Science and Technology, Class notes, Revision 2nd.
  12. Olsen NRB (2000), CFD algorithms for hydraulic engineering. Class notes, Department of Hydraulic and environmental Engineering, Norwegian University of Science and Technology, Norway.
  13. Olsen NRB (2001) CFD modeling for hydraulic structures. Norwegian University of Science and Technology, Preliminary 1st edition, 8 May. ISBN 82-7598-048-8.
  14. Olsen NRB (2009), A three-dimensional numerical model for simulation of sediment movement in water intakes with multi-block option. Department of Hydraulic and Environmental Engineering, Norwegian University of Science and Technology, SSIIM User's Manual.
  15. Sclafani P, Thornton CI, Cox AL, Abt SR (2012), Methodology for predicting maximum velocity and shear stress in a sinuous channel with bend way weirs using 1-D HEC-RAS modeling results. Colorado State University, Engineering Research Center.
  16. Shukry A (1949), Flow around bends in an open flume. American Society of Civil Engineers, No. 2411, 115(1): 785-789.
  17. Schlichting H (1979), Boundary-layer theory. New York: McGraw-Hill.
  18. Vaghefi M, Ghodsian M, Salehi Neyshabouri SAA (2012), Experimental study on scour around a Tshaped spur dike in a channel bend. Journal of Hydraulic Engineering 138(5): 471–474.
  19. Vaghefi M, Safarpoor Y, Hashemi SS (2014), Effect of T-shape spur dike submergence ratio on the water surface profile in 90 degree channel bends with SSIIM numerical model. International Journal of Advanced Engineering Applications 7(4): 1–6.
  20. Vaghefi M, Safarpoor Y, Hashemi SS (2015), Effects of relative curvature on the scour pattern in a 90° bend with a T-shaped spur dike using a numerical method. International Journal of River Basin Management 13(4): 501-514.
  21. Van Rijn L (2007), Unified view of sediment transport by currents and waves. II: Suspended Transport. Journal of Hydraulic Engineering 133(6): 668–689.