抄録
The breaking of dam can cause sudden debris flow which leads to hazardous consequences. This paper presents a coupled Computational Fluid Dynamics and Discrete Element Method (CFD-DEM) approach to study the dam break problem. The CFD is employed to investigate the fluid flow by solving the locally averaged Navier-Stokes equation, while the DEM is used to simulate the granular particle system based on the Newton’s equation of motion. The fluid-particle interaction is accounted for in the modeling by exchanging interaction forces such as the drag force and the buoyancy force between the CFD and the DEM. In simulating the dam break problem, a mixture of viscous fluid and uniform particles is initially confined within a cubic container with a removable side gate which is subsequently initiate the dam breaking. Four comparison cases are investigated, including a Bingham fluid-particle sample, a water-particle sample, a pure Bingham fluid sample and a dry particle sample. The Bingham model is employed to simulate a viscous fluid consisting of water and fine particles, which allows the DEM simulate big gravels and boulders only and lends a great computational efficiency. The simulations enable us to examine the flow patterns of different samples and interactions between particles to understand the mechanisms of dam break better.
