一维理想弹塑性体的SPH-HLLC耦合算法OA北大核心CSTPCD

A 1D SPH(smoothed particle hydrodynamics)and approximate HLLC(Harten-Lax-van Leer-contact)Riemann solver coupled method for elastic-perfectly plastic model is proposed through elastic and plastic wave analysis.In SPH simulations,each particle pair in the supporting domain generates a Riemann problem,whose solutions are substituted into governing equations.The philosophy of HLLC approximate Riemann solver is to divide the procedure into three steps:assume the whole state in elastic deformation and compute Riemann problem,and then reconstruct flux under von Mises yielding conditions and compute the final HLLC Riemann solution with reconstructed fluxes.We compare the new SPH-HLLC method with the traditional SPH method in several numerical tests,which show that this method can effectively simulate collision and reflected rarefaction waves between the materials,and it can profoundly suppress oscillations of pressure and deviatoric stress at contact interface between different materials,which the traditional SPH method finds difficult to realize.Moreover,the new SPH-HLLC scheme shows better energy performance than the traditional SPH method in 2D test case where initial kinetic energy is successfully transformed into internal energy with new SPH-HLLC scheme while total energy significantly decreases with time using the traditional SPH method.