FINITE-ELEMENT COMPUTATION OF THE VIBRATION MODES OF A FLUID-SOLID SYSTEM

In this paper we solve the interior elastoacoustic problem by a finite element method which does not present spurious or circulation modes for nonzero frequencies. It consists of classical triangular lagrangian elements for the solid and lowest order triangular Raviart-Thomas elements for the fluid. Transmission conditions at the fluid-solid interface are taken into account in a weak sense. Numerical results for some test examples are presented which show the good performance of the proposed methodology.