Discharge Coefficient for Sharp-Crested Side Weir in Supercritical Flow

Abstract

The characteristics of flow over side weirs are completely different from that of weirs normal to the approach channel. An accurate computation of discharge over a side weir mainly depends on the proper estimation of the discharge coefficient. The discharge coefficient of a rectangular, sharp-crested side weir under supercritical flow has been investigated using experimental data. The assumption of constancy of specific energy across a side weir is valid for supercritical flows generated in this study. The experimental data was analysed using multiple regression analysis with different non-dimensional parameters relevant to the problem. Moreover, a numerical solution to the equation of spatially varied flow was also proposed. The coefficient of discharge has been related to the upstream Froude number, and the ratios of the upstream water depth to the weir height and the weir length to the main channel width.