Numerical simulation of bed change under compound channels flow in two-way main channel

摘要

In a river with a two-way main channel the flow bifurcates from the straight channel into a meander channel and then reconverges into the straight channel. A numerical simulation model was developed for estimating flow and bed topography change in such a river using 2-D shallow-water equations. Simulation was applied to an actual river with a two-way main channel, and it was generally able to represent the bed topography. Factors of riverbank erosion were then considered by using the simulation results. Velocity and its distribution near the bank were found to affect localized bank erosion. The model was applied to compound flow in a two-way main channel, which was compared to flow in a single meandering main channel. The effects of a two-way channel on flow and bed topography were investigated.