Development of Discharge Prediction Model for Trapezoidal Canals using Simple Portable Flume

Abstract

Consumption of water can be optimized by metering it. In irrigation systems, many lined irrigation canals have trapezoidal cross sections. A simp le portable device for measurement of discharge in small trapezo idal agricultural canal has been analyzed in this paper. Measuring flu me consists of a cylinder positioned axially in nearly horizontal pris matic trapezoidal channel which can be quickly fixed and removed for short-time use in trapezo idal channels. The cylinder placed in the flow reduces the cross section for flow, thus creating critical flow conditions. In this paper, a new mathemat ical model has been developed to predict the discharge through a trapezoidal canal by simple cylindrical flu me using experimental data available in literature for trapezo idal canal having 1:1 side slope. Dimensional analysis has been carried out to achieve the objective of prediction of more accurate discharge than that calculated by a model availab le in the literature. The resulting non-dimensional parameters have been used to develop the proposed mathematical model and the results of the proposed model have been compared with the results of the model available in the literature.