THREE DIMENSIONAL ACOUSTIC WAVE MOTION ANALYSIS OF THE WIDE AREA BY A BOUNDARY INTEGRAL EQUATION METHOD USING A RESPONSE FUNCTION ADAPTED BOUNDARY CONDITIONS

Abstract

This paper presents 3-D analysis of wave propagation over the wide area, such as an urban block by use of boundary integral equation method(BIEM). By introducing a new response function using the mirror image with respect to the ground surface, which has arbitrary acoustic admittance, so that the element division of the ground surface becomes unnecessary, and the calculation load is mitigated. Therefore, it is enable to analyze a sound field complicated with diffraction, multiplex reflection, etc., in which the conventional geometric sound analysis method cannot give good accuracy.