Abstract
The objective of this paper is to derive explicitly the eigenpairs of the coupled cavity comprising five rigid walls and one flexible panel. First, the coupling orthogonality conditions the eigenpairs need to satisfy are derived. Using the coupling orthogonality conditions, the modal equation of the coupled cavity system is then obtained, permitting one to deal with a forced response of the coupled cavity. It is shown that the eigenfunctions governing the dynamics of both the sound and the vibration fields are expressed as the infinite sum of cluster eigenfunctions. The characteristic matrix equation is then derived, specifying the eigenpairs of the coupled cavity. In order to investigate the fundamental properties of the eigenpairs derived, a numerical analysis is conducted, revealing the presence of evanescent modes in addition to the conventional standing wave modes.
