Effect of fluidal‐structural coupling on the acoustical decays in a reverberation room in high‐frequency range

Abstract

The effect of the coupling between a sound field and test panels upon their decay behavior is investigated in high‐frequency range. Quasitransient solutions of the average energies in the room and the panels are used to estimate the reverberation times in the room and to calculate the decay curves of a test panel. Experiments are conducted to verify these solutions. The estimated and measured results are in good agreement in high‐frequency range, which indicates that the average decay behavior of the room and panels can be analyzed in terms of the average modal parameters. The amalgamation of the average modal parameters (of the test panels and the reverberation room) can be related to the Sabine absorption coefficient αSab of the panels. This result provides a possible interpretation for the αSab of a modally reactive surface and suggests a way to estimate this quantity by statistical energy analysis (SEA) method. The dependence of the αSab upon the room properties, in which the panel is measured, is demonstrated both experimentally and analytically.