3D hierarchical hp-FEM applied to elasto-acoustic modelling of layered porous media

The convergence related to mesh refinement extensions for different orders of polynomial approximation is briefly discussed for a homogeneous foam. The highest computational efficiency for reasonable levels of the error in the low-frequency region was obtained for fourth-order polynomial finite element interpolations. The main focus is on coupling conditions and on the convergence of solutions to Biot's equations in cases with multiple layers having different material properties. Simulations of a two-layered porous material with low flow resistivity suggest slow convergence rate of the fluid displacement field close to the interface between the layers.