The proposed method allows for an extended analysis of the wave analysis, internal powers, and acoustic performance of anisotropic poroelastic media within semi-infinite multilayered systems under arbitrary excitation. Based on a plane wave expansion, the solution is derived from a first order partial derivative as proposed by Stroh. This allows for an in-depth analysis of the mechanisms controlling the acoustic behaviour in terms of internal powers and wave properties in the media. In particular, the proposed approach is used to highlight the influence of the phenomena intrinsic to anisotropic poroelastic media, such as compression-shear coupling related to the material alignment, the frequency shift of the fundamental resonance, or the appearance of particular geometrical coincidences in multilayered systems with such materials.

A method to obtain the state matrix of an arbitrary linear homogeneous medium excited by a plane wave is proposed. The approach is based on projections on the eigenspace of the governing equations matrix. It is an alternative to manually obtaining a linearly independent set of equations by combining the governing equations. The resulting matrix has been validated against previously published derivations for an anisotropic poroelastic medium.

An analysis of intrinsic dynamic phenomena in anisotropic poroelastic media is presented, based on a plane wave formulation. The latter is derived from the Stroh formalism on the state variables governing the beha- viour of such media. A particular interest is given to the compression-shear coupling related to the material alignment of the anisotropic poroelastic core. This coupling motion can be directly correlated to the ma- terial mechanical parameters and affects the response of the overall structure in specific frequency ranges. Furthermore, the effect of the anisotropic poroelastic material coordinate orientation on the the acoustic and elastical response of multilayered systems with such material cores is investigated under diffuse field excita- tion conditions (i.e. only a part the mechanics which doesnt include maximum stress at rupture). An insight into other effects of anisotropy is provided, such as the frequency shift of the fundamental resonance related to the core material alignment and the appearance of particular geometrical coincidences in the acoustic behaviour of the system.