The Numerical Simulation Of Shallow Water And When It Takes Sediment

The river's surrounding and offshore have been the gathering place for human beings,so the evolution of the river will take a lot of affects for human being. It is necessary to research the law of water movement, and the numerical simulation is one of the effective ways within these methods.In the study of the shallow water, there are a lot of good practical algorithms, such as one-dimensional LAX-Wendroff,Preissomann format and characteristics of implicit difference scheme, and be applied to two-dimensional problem by operator splitting method or the ADI method. These methods can be applied to certain situations, but they are not fully intended the need of people for practical engineering problems.This article use the finite volume method to scatter the shallow water equation, and create the two-dimensional shallow water model, at the solving process of the model, pull in the approximate Riemann solution of Roe Format for obtaining numerical flux, to enable them to deal with discontinuous problems; at the question of deal with the source term, proposed the characteristic direction method of upwind format, to ensure the balance on the interface flux when deal with non-flat bottom, in the problem of the sediment analysis, based on diffusion theory, suspended sediment concentration variation along the vertical line which based on HongWu Zhang velocity distribution, this formula overcoming the shortcomings of 0 at the water surface, and the regular pattern is line with the practice. Then at the foundation of shallow water equation, add the diffusion equation and the bed deformation equation, simulating the movement of sediment and erosion deformation of the riverbed.Testing and verifying two experiment of dam break which did by some researchers in laboratory with the shallow water model:the dam break model of asymmetric square and the dam break model with triangular obstacle, by the contrast with the data of laboratory, proved the accurateness of the model.Simulated the sea of WenZhou with the model of sediment-laden flow, and contrast the tidemark,viocity and the sediment concentration with the data through measurement, then simulated the law of water movement and the erosion deformation of the riverbed between ShaShi and JianLi at Yangtze River. The result certificated the accurateness of the model.