3101 A design method for micro-structure of poroelastic sound-absorbing media by the homogenization method

Abstract

In this paper we propose a model for sound-absorbing poroelastic materials using the homogenization method, based on the asymptotic approach. The proposed model is consistent with microscopic structure and yields a macroscopic governing equation with properties predicted directly from microscopic geometry. In this model, four properties for the solid phase and two properties for the fluid phase are calculated by averaging characteristic functions of the periodic microscale model. These properties are then substituted into the macroscopic governing equations to evaluate performance such as the sound absorption coefficient for normal incidence. We show how the actual size of the microscale affects the sound absorption coefficient, using a three-dimensional microstructure model.