The Effects of Side-Weir Height on the Free Surface Turbulent Flow

摘要

Side-weirs are flow diversion devices used widely in irrigation as a head regulator of distributaries and escapes, land drainage and urban sewage systems. In this study, a numerical analysis for predicting free surface turbulent flow over the sharp crest side-weir is performed. The Volume of Fluid (VOF) scheme and Reynolds Stress Model (RSM) turbulence model are used to numerical simulation of the turbulence free surface flow. Comparison between numerical results and laboratory measurements show that the model had predicted experimental trends with reasonable accuracy. In next steps of this study, the side-weir height effects on the flow pattern are investigated. The parametric study results show that under the low and high overflow rate conditions, the flow characteristics in low side-weir situation is virtually the same as the side-weir of zero height while in high weir situation, significant changes occurred in the shear stress and the water head above the weir crest.