Improvement Of ISPH Method And Its Application In The Interaction Of Wave And Structure

With the exploitation of land resources exhausted,the human energy in the future exploitation of the ocean must come from,so the interaction between waves and structures of the study was particularly important.Smooth particle hydrodynamics(SPH)method is a discrete method with Lagrangian characteristics,and has a very large application space in the study of wave object coupling.Compared with the fully incompressible SPH(ISPH)method for the compressible SPH(WCSPH)method,the pressure solution of Poisson equation is used instead of the state equation to obtain the pressure,which greatly improves the accuracy of the pressure solution.At present,traditional ISPH method has disadvantages in solving high-order functions by using kernel approximation.In this paper,simplified finite difference method(SFDI)is used to improve the interpolation precision of ISPH method.Based on the SFDI method,the pressure solution of the boundary particle is improved.From the Poisson equation for solving the pressure,the pressure is solved by the boundary condition.The solution of the pressure makes the solution of the boundary particle no longer depend on the mirror particles,which improves the defect of the ISPH method in dealing with the complex shape boundary.The results of the experiments show that these improvements are effective.However,in the simulation of some strong nonlinear waves and structures of the role,the pressure calculation part will still produce severe jitter,the key to this situation is that the particles in motion will produce a very chaotic distribution,which will lead to In this paper,we propose three correction methods to improve this problem.The first one is based on the Fick's law(ISPH_BSF)and the second is the pressure stabilization method using the minimum pressure.ISPH_BSP),and the third is a new numerical stability method(ISPH_BSPF)that combines position correction with pressure stability.In this paper,the advantages and disadvantages of the three improved methods are analyzed and compared using the classic examples.It is concluded that the ISPH_BSPF method can solve the above problems.Finally,the coupling analysis of the solitary waves attacking the fixed complex structures,nonlinear wave and floating structure and the wave phenomenon of the floating structure in the nonlinear wave are simulated by using the ISPH_BSPF method.After comparing with the experimental data,the numerical stability method proposed in this paper not only improves the stability of the original ISPH method,but also effectively controls the phenomenon of particle strip distribution,so that in the study wave and structure mutual The role of the time to obtain very good results.