Simulations of the dynamics and interaction between a floating structure and a near-field explosion bubble

Abstract

The simulation of the interaction between a surface ship with a near-field underwater explosion bubble is performed using the three-dimensional (3D) boundary integral method for simulating the physical process of the bubble coupled with the finite element method for calculating the structural response in conjunction with the doubly asymptotic approximation for handling the fluid-structure interaction problem. An indirect procedure is proposed solely for investigating the effect attribute to the free surface elevation on the bubble dynamics and the structural response through a comparison of two different 3D boundary integral numerical methods. The present model is validated by comparing the numerical simulation results with the experimental data. For a near-field explosion, the results indicate significant effects due to the free surface elevation on the bubble dynamics and transient response of the ship hull, including modification of the bubble pulsation period and the pressure distribution on the wet surface, which is the key initiator of the destructive action. The transient structural response characteristics including the global and local response of the hull ship subjected to an underwater explosion bubble are investigated in detail and the related mechanism behind the phenomena are also analyzed.