Author(s)

S. Zhou & D. C. Rizos

Abstract

This work presents a direct time domain methodology for Fluid-Structure Interaction analysis between linearized fluids and rigid bodies. To this end, a direct time domain Boundary Element formulation pertaining to 3-D wave propagation in acoustic media is developed. The method is based on higher order B-Spline fundamental solutions developed for scalar wave propagation in 3-D infinite media and uses higher order spatial discretization. Integration of singularities appearing in the fundamental solutions is treated numerically through triangle coordinates and a successive mapping technique. This method is used within the B-Spline Impulse Response framework for the calculation of the time history of the response of the acoustic medium and the calculation of the hydrodynamic forces on the wetted surface of the fluid-structure interface. The proposed B-Spline BEM is stable as compared to the relevant Retarded Potential formulations reported in the literature. Although this method is non-local in time, only a relatively small number of time steps are required in the B-Spline Response functions, making the method very efficient especially for prolonged external excitations. Fluid-Structure interaction models are proposed for the dynamics of rigid bodies submerged in, or floating on, semi-infinite fluid domains. Validation of the BEM is presented in the application examples. The accuracy stability and efficiency of the proposed models are also demonstrated. Keywords: boundary element method, fluid-structure interaction, scalar wave propagation.

Keywords

boundary element method, fluid-structure interaction, scalar wave propagation