Modeling of perforated plates and screens using rigid frame porous models

There are several models and approaches for predicting the acoustic response of perforated plates and screens. Classical models are devoted to specific configurations: particular geometrical parameters including the size and shape of the perforations, excitations type, mounting of the screen (bonded vs. free), and interfacing media involved in multilayers sound packages. This paper reviews these models and presents a simple and general model that can handle easily and automatically the miscellaneous configurations in the context of the transfer matrix method. In particular, it is shown that a perforated plate or screen can be modeled as an equivalent fluid following the Johnson-Allard approach with an equivalent tortuosity. This equivalent tortuosity is shown to depend on the media interfacing with the perforated system. Experimental results depicting various practical configurations are shown to corroborate the validity of the proposed model and to evaluate its performance compared to classical ones. (c) 2007 Elsevier Ltd. All rights reserved.