عنوان مقاله [English]
In order to decrease the amount of sediment entering intakes, skimming wall could be used as control structure. Skimming wall changes the flow pattern and consequently changes the volume of sediment. In intakes, the average of the flow lines angles that enter the intake increases from the floor to the surface. The main propose of this research was to evaluate the effects of skimming wall and spur dike in controlling the sediment entrance and to find out the changes in velocity. The velocity components were determined in two dimensions- in the direction of the channel's length and perpendicular to flow in front of the span of the intake- and the angle of entry of the flow along the span of the intake. The velocity distribution and the method of entering and transporting of sediment to the intakes in different layers were investigated by using velocity angle of the entrance of flow to the intake and the longitudinal and transverse components of the velocity, Changes of velocity in front of the intake were compared in three layers. The results showed that the velocity angle of the surface layer was higher than that of other layers, due to directing of flow through the spur, the existence of a separator wall structure and the effects on the middle and floor layers,. The spur dike caused longitudinal velocity near the bed layer increased 2.25 times, and the transverse velocity in the surface layer increased 1.33 times comparing to when there is no spur dike.
Abbasi, A. A. 2003. Experimental investigation of sediment control at lateral intakes. Ph. D. Thesis in Hydraulic Engineering. Tarbiat-Modares University, Tehran, Iran. (in Persian)
Barkdoll, B. D., Ettema, R. and Odgaard, A. J. 1999. Sediment control at lateral diversions: limits and enhancements to vane use. J. Hydraul. Eng. 125(8): 862-870. Doi: 10.1061/(ASCE)0733-9429(1999)125:8(862).
Ettema, R. and Muste, M. 2004. Scale effects in flume experiments on flow around a spur dike in flatbed channel. J. Hydraul. Eng. ASCE. 137(4): 635-646.
Hsu, C., Tang, C., Lee, W. and Shih, M. 2002. Subcritical 90 equal-width open-channel dividing flow. J. Hydraul. Eng. 128(7) 716-720.
Moradinejad, A., Haghighi, A. H., Sanei, M. and Younesi, H. 2017. Experimental investigation of the effect of simultaneous use of skimming wall and spur dike on hydraulics of flow and sediment transport in in the vicinity of the intakes. Ph. D. Thesis in Hydraulic Engineering. Lorestan University, Iran. (In Persian)
Moradinejad, A., Haghighi, A. H., Sanei, M. and Younesi, H. 2018. Investigating the effect of the skimming wall on the flow velocity pattern. The 5th National Conference on Irrigation and Drainage Management and the 3rd Iranian National Irrigation and Drainage Congress. March 17. Ahvaz, Iran. (In Persian)
Neary, V. S. and Odgaard, A. J. 1993. Three-dimensional flow structure at open channel diversions, J. Hydraul. Eng. ASCE. 119(11): 1224-1230.
Neary, V. S. and Stavropoulos, F. 1996. Numerical investigation of laminar flows through 90-degree diversion of rectangular cross-section. Comput. Fluid. 25(2): 95-118.
Neary, V. S., Sotiropoulos, F. and Odgaard, A. 1999. Three-dimensional numerical model of lateral-intake inflows. J. Hydraul. Eng. 125(2): 126-140. doi:10.1061/(ASCE)0733-9429(1999).
Ouyang, H. T. 2009. Investigation on the dimensions and shape of a submerged vane for sediment management in alluvial channels. J. Hydraul. Eng. ASCE. 135, 209-217.
Ramamurthy, A. S., Qu, J. and Vo, D. 2007. numerical and experimental study of dividing open-channel flows. J. Hydraul. Eng. 133(10): 1135-1144. doi: doi:10.1061/(ASCE)0733-9429.
Raudkivi, A. J. 1993. Sedimentation, Exclusion and Removal of Sediment from Diverted Water. IAHR, IAHR Hydraulic Structures, Design Manual. CRC Press.
Sayyidan, S. M., Shafai-Bejestan, M. and Fathi-Moghaddam, M. 2010. Laboratory study of the effect of channel wall slope on sediment input to the catchment. Ph. D. Thesis. Department of Structural Engineering, Shahid Chamran University of Ahvaz, Ahvaz, Iran. (in Persian)
Shafai-Bejestan, M. and Nazari, C. 2010. The effects of intake angle on the discharge and sediment ratio to an intake in a 90-degree convergence bend. Sci. J. Agric. 22(1): 45-33. (In Persian)