Surface treatment technique of MPS method for free surface flows

摘要

A surface treatment technique is developed for moving particle semi-implicit (MPS) method in the simulation of incompressible free surface flows. The free surface particles are accurately detected by a developed geometrical method. Material interface is reconstructed at the interface of the fluid. According to the definition of level set function, the level set value of each particle is set to be the signed distance to the interface. The normal vector and curvature of interface are calculated at the position of interface via level set function, which help to obtain the accurate calculation of surface tension. The smoothness of level set function improves the computational accuracy of the interface curvature. The computational curvature has high convergence in current method. For example, the computational curvature of a circle has 1.75-order convergence. Benchmark tests including square droplet oscillation, head-on and off-center binary collision illustrate the advantages of current method. The developed method has higher accuracy and stability in the simulation of low speed incompressible free surface flows.