Numerical Simulation of Interaction Between Tributary Debris Flow and Main River

<正>Based on two-phase flow theory and shallow water flow assumption,a mathematical model is applied to simulate debris flow.The model considers a two-phase mixture of sediments and water fluid.Assuming that the sediments and the water fluid move downstream with the same velocity,the flow of the mixture is described using a two dimensional depth averaged model with a unique 2-D momentum equation and two mass balance e- quations for the mixture and the sediments,respectively.The finite volume method is used for the iterative so- lution of the mathematical model,and upwind schemes (Roe's approximate Riemann solver or Van Leer's flux splitting) are used to compute convection fluxes.The pressure-velocity coupling is obtained from the combina- tion of the continuity equation and the equations of momentum by the SIMPLE algorithm.