Flow Investigations in a Wide Meandering Compound Channel

Abstract

Extreme complexities present in flow behavior of meandering compound channels necessitate the study and analysis of such channels under different geometric and hydraulic condition to further our knowledge in understanding the dependency of flow characteristics e.g. velocity, boundary shear etc. on different sectional parameters like width ratio, aspect ratio and hydraulic parameter such as relative depth. The present paper draws on our investigations on a meandering compound channel,where physical experiments were conducted on a smooth sine generated trapezoidal main channel flanked on both sides by wide flood plainsunder different relative depths. A 2dimensional hydrodynamic model CCHE2D and another quasi1D model Conveyance estimation System (CES) were then applied in turn to the same test cases to numerically investigate the flow in the compound meandering channel. The results of such investigations were then compared for validation purpose with observed experimental values of important flow parameters like depth averaged velocity and boundary shear distribution across the channel cross section. It is seen that CCHE2D is quite capable of producing results in agreement with their physical values and also it partly agrees with results of CES.It is expected that the results shown in this paper would enrich the research data base in the field of compound channels and help the scientists in using the numerical model CCHE2D, as a viable research tool in the field of river engineering.