Numerical simulation of column charge underwater explosion based on SPH and BEM combination

摘要

Underwater explosion detonated by column charge can generate exceedingly high-pressure shock wave, bubble pulsing and high-speed jet formed by bubble. Its physical course involves many complicated problems such as transient state, high temperature and high pressure, large distortion and multi-medium flow. For this reason, axisymmetric Smoothed Particle Hydrodynamics (SPHs) numerical model was established combined with Boundary Element Method (BEM) to simulate the whole process of underwater explosion detonated by column charge in this paper. Calculation results of various phases such as shock wave propagation, bubble pulsing and jet formation agree well with the experiment values. In this study, column charge detonation and bubble jet are successfully simulated via axisymmetric SPH method. The calculation results are still of highly precise at the symmetrical axis, verifying the feasibility of the axisymmetric SPH method established in this paper in the computation of three-dimensional underwater explosion, bubble jet and other physical problems. Meanwhile, axisymmetric SPH method and BEM are successfully combined in this paper to fully utilize their advantages, which is favorable in the solution of other hydrodynamic problems.