Dynamic simulation of fast attack craft subjected to Underwater Explosion (UNDEX)

In this paper the dynamic simulation of a new Fast Attack Craft subjected to underwater explosion (UNDEX) is discussed. Field response results of a global model containing the whole structure are presented. The surrounding water enabling the cavitation phenomenon was included into the model as acoustic domain. In addition, the effects of gravity and buoyancy were included into the analysis. As excitations to the model shockwave and free surface reflections were used. Filtering was used to control the frequency content of charge detonation excitations.The Fast Attack Craft hull is constructed of aluminum alloy. Nonlinear Ramberg-Osgood plasticity model and Cowper-Symonds power law model for strain rate effects and failure conditions were included into the material model. Analyses were carried out by using Abaqus finite element code in a multi-processor Linux computer.