The Estimation of the Sound Power Radiating from a Peripherally Fixed Rectangular Plate Subjected to Acoustic Excitation. 1st Report, Derivation of Estimation Formulae and Application to a Plate Subjected to a Normal Plane Acoustic Wave Excitation.

Abstract

This paper describes the estimation method of sound power radiating from a peripherally fixed rectangular plate which is subjected to a sound excitation. The forced vibration of the plate which is excited by a distributed force has been theoretically solved by using modal analysis with Rayleigh-Ritz method. The basic equation for estimation has then been shown, and the equations of the frequency response of three parameters-total loss factor, radiation loss factor and input power for estimating sound power-have been derived. For a practical instance, the sound power radiating from a peripherally fixed rectangular steel plate, which was excited by the normal plane acoustic wave, has been estimated. The estimated frequency responses of the sound radiation power coincided well with the measured values obtained by the sound intensity method. This proposed method is hence effective to estimate the sound power radiating from a plate subjected to an acoustic excitation.