Structural-acoustic coupling analysis of orthotropic rectangular panel backed by a rectangular cavity

Spectro-Geometric Method (SGM) is presented to deduce a theoretical solution for vibration analysis of orthotropic rectangular panel backed by a closed rectangular cavity. Under this solution framework, the admissible function for panel and rectangular cavity is invariantly expressed as a new trigonometric series in the form of the superposition of a Fourier cosine series supplemented by sine terms. The continuity of the boundary edges and coupling surface can be satisfied. Numerical examples are carried out to validate the validity of the theoretical model. Key parameters, the depth of cavity and thick of panel, are the crucial structural parameters influencing the structural-acoustic analysis of rectangular panel. It is concluded that the coupling degree is reduced along with the increasing of panel thick and cavity depth. In the strong coupling region, the coupling frequency is depended much on cavity depth than the panel thick does. In the weak coupling region, the influence of panel thick and cavity depth are inclined to identical.