Investigating the Effects of Porous Material Compression on the Acoustical Behavior of Absorption and Barrier Materials

The paper discusses the effects of compression on acoustical performance of porous materials. A finite element model is used to predict the absorption coefficient and transmission loss of absorbing and barrier materials. This model is developed based on the Galerkin method and includes the equation of wave propagation in rigid frame porous material. The compression of porous material is entered to the model with relations that explain modifications of physical properties used in wave equation. Acoustical behavior of absorption and barrier materials with and without compression is studied. It is shown in this paper that compression of the material leads to improvement of the transmission loss of the barrier materials, whereas absorption coefficient reduction has been obtained for absorbing materials.