Time domain numerical modeling of wave propagation in 2D heterogeneous porous media
For researchers simulating wave propagation in porous media, this method addresses the challenge of handling both fast and slow compressional waves with improved accuracy and efficiency.
The paper develops a numerical method for modeling wave propagation in 2D heterogeneous porous media based on Biot's theory, splitting the system into propagative and diffusive parts to avoid time step restrictions. Numerical experiments confirm accuracy, and simulations of multiple scattering demonstrate efficiency.
This paper deals with the numerical modeling of wave propagation in porous media described by Biot's theory. The viscous efforts between the fluid and the elastic skeleton are assumed to be a linear function of the relative velocity, which is valid in the low-frequency range. The coexistence of propagating fast compressional wave and shear wave, and of a diffusive slow compressional wave, makes numerical modeling tricky. To avoid restrictions on the time step, the Biot's system is splitted into two parts: the propagative part is discretized by a fourth-order ADER scheme, while the diffusive part is solved analytically. Near the material interfaces, a space-time mesh refinement is implemented to capture the small spatial scales related to the slow compressional wave. The jump conditions along the interfaces are discretized by an immersed interface method. Numerical experiments and comparisons with exact solutions confirm the accuracy of the numerical modeling. The efficiency of the approach is illustrated by simulations of multiple scattering.