Dynamics of an underwater explosion bubble near a sandwich structure

Abstract

A numerical procedure that couples the Runge–Kutta discontinuous Galerkin method (RKDG), the boundary element method (BEM) and the finite element method (FEM) is developed to study the dynamics of an underwater explosion bubble near a sandwich structure efficiently and accurately. The numerical approach is validated by a near-field underwater explosion experiment. The numerical predicted bubble shape, cavitation and the free field pressure are in good agreement with the experimental results. The validated code is then used to determine the effects of the foam core strengths, the stand-off distances and the boundary condition of the back face sheet on the fluid response, the bubble behaviors, and the deformation of the sandwich structure. The results are beneficial for guiding the design of the protection structures.