Determination of experimental flow curves for a 6" Parshall flume based on the variation in the channel bottom slope

Abstract

This article reports the results of research based on experimental laboratory tests of a Parshall flume with a 6-inch throat width, designed and constructed in accordance with ASTM D1941-21 standard, made of polymethyl methacrylate (acrylic), installed inside the hydrodynamic channel of the Center for Research and Studies in Water Resources Engineering at the National Polytechnic School (CIERHI – EPN); the tests determine the variation in measured flow rates based on the variation in the slopes of the bottom of the hydrodynamic channel  (5 slopes) under free discharge conditions. The resulting experimental flow curves are compared with the standardized theoretical-empirical curve, the relative errors and differences are obtained, and graphic zones are established on the corresponding chart, where the maximum tolerable relative error for the flow rates measured with the theoretical curve is Er = 10%.