An improved hybrid FE-SEA model using modal analysis for the mid-frequency vibro-acoustic problems

Abstract

Based on the hybrid finite element (FE)-statistical energy analysis (SEA) method, an improved hybrid model with less time-consuming is proposed for the mid-frequency vibro-acoustic problems. Mode shapes are used to reduce the order of the deterministic acoustic component modeled by the finite element method in this paper. The governing equation of the residual response, which is derived to correct the modal truncation error, can be reduced by constructing a set of basis vectors. The model order reduction (MOR) equation of the acoustic component is formulated through a combination of the truncated mode shapes equation and the reduced residual response equation. The dimension of the overall equation of motion is efficiently decreased. The statistical structural component is modeled by SEA, and the responses of a mid-frequency vibro-acoustic system can be solved after introducing the diffuse field reciprocity relationship. Based on the efficient correction of the modal truncation error, the proposed hybrid MOR-SEA method promotes the reduction of order using mode shapes in mid-frequency vibro-acoustic systems. Compared with the traditional hybrid FE-SEA method, the present method has an evident advantage in computational efficiency, as shown in two numerical examples.