Weir‐Orifice Units for Uniform Flow Distribution

Abstract

A method to analyze the flow through lateral weir‐orifice units (partitioned weirs) in a flow distribution channel is presented. For purposes of analysis, a single unit of weir‐orifice combination is considered. Flow through rectangular lateral weir‐orifices is obtained using an existing hydrodynamic model for the lateral efflux from a two‐dimensional channel. The design procedure for proportioning the weir‐orifice unit for a given inflow is discussed. It is shown that weir‐orifice units can be properly designed to ensure an outflow that is a prescribed percentage of the channel inflow over a range of upstream flow depths. The experimental data obtained in a test flume provide a verification of the theoretical relationship between the geometric and hydrodynamic parameters of the weir‐orifice flow. The predicted relationships are valid for flow through a lateral weir‐orifice unit that can be as wide as the main channel.