Finite element solution of new displacement/pressure poroelastic models in acoustics

This paper deals with acoustical behavior of porous materials having an elastic solid frame. Firstly an overview to poroelastic models is presented, and then we focus our attention on non-dissipative poroelastic materials with open pores. Assuming periodic structure we compute the coefficients in the model by using homogenization techniques which require solving boundary-value problems in the elementary cell. Next we propose a finite element method in order to compute the response to a harmonic excitation of a three-dimensional enclosure containing a free fluid and a poroelastic material. The finite element used for the fluid is the lowest order face element introduced by Raviart and Thomas that eliminates the spurious modes whereas, for displacements in porous medium, the “MINI element” is used in order to achieve stability of the method.