A computationally efficient prediction technique for the steady-state dynamic analysis of coupled vibro-acoustic systems

A new prediction technique has been developed for the steady-state dynamic analysis of coupled vibro-acoustic systems. In contrast with the finite element method, in which the dynamic field variables within each element are expanded in terms of local, non-exact shape functions, the dynamic field variables are expressed as global wave function expansions, which exactly satisfy the governing dynamic equations. The contributions of the wave functions to the coupled vibro-acoustic response result from an integral formulation of the boundary conditions. This paper describes the basic concept of the new technique for the modelling of the vibro-acoustic coupling between the pressure field in an acoustic cavity with arbitrary shape and the out-of-plane displacement of a flat plate with arbitrary shape. It is illustrated through a three-dimensional validation example that the new prediction technique yields a high accuracy with a substantially smaller computational effort than the finite element method, so that the new prediction technique can be applied up to much higher frequencies. (C) 2002 Civil-Comp Ltd and Elsevier Science Ltd. All rights reserved.