NUMELICAL SIMULATION OF SAND BARS UNDER UNSTEADY FLOW

Abstract

Sand bars in rivers have important effects on river meandering, which cause change of flow and disasters in rivers. There are a lot of studies on bars under steady flow. But unsteady flow (ex. artificial flood) has been considered to restore river environment. It has become more important to predict bed topology under unsteady flow.
In this paper, we calculate changes in riverbed by using 2-D shallow water equation model. The points of this simulation are boundary condition and shape of flood wave. Periodic boundary condition was applied to unsteady flow analysis. We compare with the result of numerical simulation and experiment results. Knowledge on boundary condition in the simulation can be gotten in this research.