Flow Computation in Symmetric and Asymmetric Compound Channels Using Conveyance Estimation System

Abstract

There is a tough interaction between the flow of main river channel and its floodplain in a compound channel. So the discharge at different interfaces of the compound sections varies greatly. There are many reports found in literature related to compound channel with symmetric floodplains, and very few are found for asymmetric cases. In a symmetric compound channel, exchange of the momentum occurs uniformly from main river channel to its adjoining floodplain. But in case of an asymmetric compound channel, a stronger interaction occurs between the subsections of the whole compound channel compared to the symmetric case. Many researchers have studied and modeled in predicting the flow variables for the symmetric compound channel. In this paper, the application and suitability of using the standard software Conveyance Estimation System (CES) for predicting the flow is described. The approaches were also applied to a number of experimental data sets, and the results were compared well. Three different division methods have been used for predicting discharge in four channels with varying geometric and hydraulic conditions. The divisions are generally based on the location of vertical, horizontal, and inclined interfaces of the channel. CES software tool is used for simulating the flow variables, and the applicability of the software CES to such channels is discussed. The results from three division methods and the CES have been utilized for assessing the discharge and finding out the best predicting model through error analysis.