Modèle de prévision acoustique en espace clos basé sur les hypothèses de réflexion diffuse et spéculaire en parois

Abstract

This paper presents a mathematical model for the calculating of sound fields in inclosed areas, even where the internal dimensions are disproportionate: particular reference is made to the diffusive effect of walls. The model is based on a classical ray tracing method. However, not all of the reflected energy necessarily follows the specular path; some of it can be scattered, forming, as it were new sources. The coefficient of diffusion associated with the sample of wall involved in the reflection regulates the sharing of the reflected energy. In order to determine this diffusion coefficient, we have developed a method that allows the measuring of the diffusion of a sample of wall. We have measured the sound propagation curves in several factory halls and compared the results to the previously calculated values. The high degree of correlation between the theoretical and experimental results validates the model and our approach of the coefficient of diffusion