This paper presents a reduced order finite element model for sound transmission analysis through a double-wall sandwich structures with viscoelastic core inserted in an infinite baffle. The proposed model is derived from a multi-field variational principle involving structural displacement and acoustic pressure inside the fluid cavity. To solve the vibro-acoustic problem, the plate displacements are expanded as a modal summation of the plate's eigenfunctions in vacuo. Similarly, the cavity pressure is expanded as a summation over the modes of the cavity with rigid boundaries. Then, an appropriate reduced-order model is introduced. The structure is excited by a plane wave at the source side. An example of the normal sound transmission loss of a double glazed window with laminated glass is shown. This example illustrates the accuracy and the versatility of the proposed reduced order model, especially in terms of prediction of sound transmission.
展开▼
