Structural acoustics of perforated panels

Abstract

In this work, radiation and transmission of sound through flexible perforated panels set in infinite rigid baffles are investigated. The treatment is largely analytical using Fourier transforms and contour integrations. Numerical calculations are only used occasionally. The work is largely divided into three parts: the first part involves radiation and transmission studies using the one-way coupled formulation, the second part investigates the same problems using the two-way coupled (or the fully-coupled) formulation and the third part involves derivations of closed form expressions for the modal coupling coefficient using contour integration. In the first part, the panel with perforations is placed in a baffle that is perforated or unperforated. Having an unperforated or a differently perforated baffle presents challenges. It causes a certain coupling of wavenumbers leading to an integral equation. In the literature so far, the baffle has been taken to be similarly perforated, thus, simplifying the situation. The perforations are arrays of circular holes and are mathematically modeled using a perforation ratio... newline