Numerical simulation of underwater explosion using smoothed particle hydrodynamics

Abstract

Underwater explosion generates various physical phenomena such as shock wave, bubble pulsation and bubble jet. These phenomena involve complicated problems, which consist of high pressure, large deformations and multi-interface flow, etc. In this study, a Lagrangian meshless method, smoothed particle hydrodynamics(SPH) is applied to simulate the whole process of underwater explosion. It has different time scale and equation of state for pressure term between shock physics and bubble dynamics in standard SPH formulation. For this reason, numerical modules for each phenomenon are presented separately, and a method for obtaining the transition point where the module is converted is proposed. In addition, a modified state equation is presented to implement the gas bubble pulsation phenomenon. The numerical model verification is performed via comparing with empirical formulas, other numerical methods, and experiments.