Hydroelastic analysis of floating structures subjected to underwater explosive bubbles

Abstract

The coupled model for the interaction between an underwater explosive bubble and a floating structure is studied. During the violent expansion and collapse of the bubble, the explosive bubble deforms the structure. At the same time, the response of the structure affects the behavior of the bubble. In this study, the fluid domain for the bubble is modeled by using the boundary element method and the structure domain is modeled by using the finite element method. Based on the acceleration potential theory, we can construct a single set of coupled equations considering both the behavior of the bubble and the response of the structure simultaneously. In this study, we apply the quadratic surface fitting for constructing the coupled equation to avoid complex computation and weighted least square to minimize the error. To validate our model, we compare the results with both the rigid wall case and the free surface case. Then, the numerical example of steel plate is compared with LS-DYNA. Additionally, the change of the behavior of the bubble according to the stiffness of the plate is studied.