Multi-phase moving particle semi-implicit method for violent sloshing flows

Abstract

As a meshless technique, the moving particle semi-implicit (MPS) method has extensive applications in numerical studies on violent sloshing flows. However, most prevalent research in the area is based on the single-phase MPS method, which ignores the existence of the air phase. This study aims to illustrate the necessity of multi-phase simulations for representing violently sloshing liquid through a comparative analysis between single-phase and multi-phase MPS methods, and to better figure out the air effect in the violent sloshing flows The MMPS (multi-phase MPS) method is firstly developed by introducing various multi-phase models into the single-phase IMPS (improved MPS) method, and then verified through simulations of two classical examples: the static multi-fluid system and the Rayleigh–Taylor instability. Subsequently, both the MMPS and the IMPS methods are applied to simulate liquid sloshing with increasing intensities, and their numerical results are compared with each other and with experimental data. The comparisons show that as the intensity of sloshing increases, the effect of the air cushion become non-negligible and the accuracy of the single-phase simulation significantly decreases, whereas the simulation results obtained by the MMPS method agree well with the experimental results in all cases. In particular, the MMPS method fully considers the air cavity formed in case of a violent wave breaking as well as its influence on waves of the sloshing liquid, and rectifies the overestimation of impact pressures in single-phase simulations.