Fast Time Domain Boundary Element Formulation for Partially Saturated Porous Media
In many engineering applications the simulation of waves in unbounded domains is required. One example is soil-structure-interaction. In these multiphysical problems several computational methods have to be used and it is well known that a correct model for the radiation of waves in the unbounded domain is necessary. The Boundary Element Method (BEM) in time domain is the method of choice for this part of the problem. In case of, e.g., soil, the material behavior may be modeled by a linear three phase poroelastic model.
In this project a three phase poroelastic model based on the mixture theory is used. The fundamental solutions necessary for the BEM can be derived in Laplace domain and are implemented in a Convolution Quadrature based BEM. To obtain an efficient method this time domain BE formulation is accelerated by employing fast techniques. The Adaptive Cross Approximation and the Panel Clustering will be applied. Unfortunately, the efficiency of both methods decreases with frequency. But the Panel clustering can be improved for larger frequencies by using a directional clustering. Hence the behavior of both techniques in the low and higher frequency regime will be compared and presumably a combination of both will result in an efficient method.