A SYMMETRICAL FINITE ELEMENT MODEL FOR STRUCTURE–ACOUSTIC COUPLING ANALYSIS OF AN ELASTIC, THIN-WALLED CAVITY

This paper sets up a symmetrical finite element model for structure–acoustic coupling analysis of an elastic, thin-walled cavity excited both by interior acoustic sources and exterior structural loading. Some relative problems on the symmetrical model, i.e., the non-negativity conditions of eigenvalues, the reduced-order modelling conditions of eigenvalue problem, and the unavailability of the state space method to this model in complex modal analysis, are discussed. Finally, in order to verify the feasibility and correctness of the symmetrical method given in this paper, a calculating example which possesses a rectangular section cavity is given, and the calculated results are compared with the measured ones.