CFD SIMULATION OF FLUID FLOW OVER RECTANGULAR WEIR

Abstract

Weirs are a sort of hydraulic structure that is used in irrigation systems to manage water levels, monitor flow, and divert water. Weirs are one of the earliest and most fundamental hydraulic structures, having been used for many years in open channels by hydraulic engineers for flow monitoring, energy dissipation, flow diversion, flow depth management, flood passage, and other uses. Many experimental investigations on various types of weirs have been conducted in the past years, but there is a limitation on literature on simulation techniques. The aim of this study is to examine the flow behavior of the rectangular weir using the CFD simulation. For this study, a full width rectangular weir with two separate crests was used (sharp and normal) in order to find out the flow behavior. The finding of the present study are in good agreement with past studies or research. ANSYS post processing is used to create velocity contours, volume fractions, streamlines, and velocity vectors, among other things. The discharge coefficient was studied for various (h/p) ratios, and the findings revealed that the discharge coefficient decreased nonlinearly when the (h/p) ratio increase up to certain level than it shows constant trend.