Prediction of Depth-Averaged Velocity and Boundary Shear Stress Distribution in a Single-Stage Channel by Lateral Distribution Method

Abstract

This paper examines the use of LDM (Lateral Distribution Method) in the computation of depth-averaged velocity and boundary shear stress in the single-stage channel (simple channel). Generally in the non-monsoon time the river flows within the bank that means the water flows within the river only. We consider a trapezoidal channel of four different depths for the present analysis. Finding the depth-averaged velocity and the boundary shear stress is always a challenge for water resource engineer. The efficiency of the model mainly depends upon three parameter: (1) surface parameter like manning’s n, chezy’s c, Darcy’s f; (2) geometrical parameter like area, hydraulic radius; and (3) hydraulic parameter friction slope. In this research work, the LDM equation is discretized by finite difference scheme, and for solving those equations, MATLAB tool is used. CES (Conveyance and Afflux Estimation System) is commercial software which is used for the computing depth-averaged velocity and boundary shear stress in open-channel flow. In this paper, the detailed mathematical solution of LDM by finite difference method is presented for the simple channel case. The results of depth-averaged velocity and boundary shear stress obtained from LDM approach are validated well with the experimental datasets and this LDM approach is compared with the numerical software CES and gives satisfactory results for simple channel.