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Porous materials are extensively used in the construction of automotive sound package parts, due to their intrinsic capability of dissipating energy through different mechanisms. The issue related to the optimization of sound package parts (in terms of weight, cost, performances) has led to the need of models suitable for the analysis of porous materials' dynamical behavior and for this, along the years, several analytical and numerical models were proposed, all based on the system of equations initially developed by Biot. In particular, since about 10 years, FE implementations of Biot's system of equations have been available in commercial software programs but their application to sound package parts has been limited to a few isolated cases. This is due, partially at least, to the difficulty of smoothly integrating this type of analyses into the virtual NVH vehicle development.

A poroelastic material can be represented as a material that is constituted by two phases: a structural phase given by a solid frame, and a fluid phase given by the air that fills the pores of the solid frame itself. In the mid frequency range, the physical behavior of both phases and their interactions need to be properly modeled in order to predict accurately the dynamic behavior of the porous material. This can be done using finite elements based on Biot's theory, which describes the macroscopic behavior of poroelastic materials by characterizing them through a set of parameters directly measured on material samples. In this paper, numerical/experimental correlations obtained using two commercial software programs that implement libraries of poroelastic materials are presented. A free-free steel plate covered by a 20mm thick layer of foam and a massive heavy layer has been selected as a first test case.