The Application Of The SPH Method In Dam-break Water Flow Simulation

As a kind of pure Lagrangian meshless method,Smooth Particle Hydrodynamics(Smoothed Particle Hydrodynamics,SPH)method could avoid the mesh tangles and distortion problem in the mesh method.SPH had unique advantages in dealing with large deformation on the free surface and moving boundary problem,and was suitable for simulating dam break water flow.Recently,there had been significant processes in the applications of standard SPH to dam-break behavior modeling.Most of them targeted on coastal flow simulations of water structure interaction,water wave generation and water wave breaking.But the research of the SPH method to solve the shallow water wave equation(SWE)was still in the exploratory stage.After the study of the basic idea and principle of SPH method and SPH variational form of shallow water equation,in order to deal with arbitrary complex terrain,source term is discreted by SPH interpolation.Solid boundary treatment is fixed by using the rencent virtual boundary particle method.In order to improve the calculation accuracy and stability and reduce the numerical oscillation,MUSCL refactoring is combined with artificial stability.A variety of problems of 2D dam break flows in the flat bed were simulated,including flows over smooth bed(wet-bed and dry-bed),bed with roughness and partical dam break.Calculation results were in good agreement with the theoretical solution and test data,proving the feasibility and accuracy of model,and the ability to deal effectively with large deformation and wet-dry interfaces.The result of calculation was more ideal if MUSCL reconstruction is added into stable item.Some research in particle spacing to influence on calculation accuracy was made.For dam break flow over bed with fiction and different obstacles(triangle,rectangle,bump),agreement between numerical and measured results was generally satisfactory.Complex flow details were reproduced,such as dam wave reflection,diffraction,whirlpool and hydraulic jump.Finally,a practical project of the dam water flow simulation is carried on the preliminary attempt.In addition,Matlab post-processing was worked out for different needs to realize the visualization of numerical simulation results.