Anisotropic BEM formulation of multiple scattering of elastic waves by distributed inclusions

摘要

In this paper we present a simple, and computationally efficient, formulation of multiple scattering by distributed inclusions and cracks in generally anisotropic solids based on a 2D elastodynamic boundary element method (BEM). The method is based on the integral representation of an elastic wavefield by assuming a fictitious source distribution on the scattering objects or inclusions, i.e. a mathematical description of Huygens' principle, and the fictitious source distribution can be found by matching appropriate boundary conditions at the boundary of the inclusions. The exact integral form of the elastodynamic Green tensor in anisotropic media is very difficult to evaluate numerically and is not practical for BEM implementation, and in this paper a stationary phase solution for the far field (or ray) Green tensor is used. Our method can be used to study multiple scattering of elastic waves by inclusions of any distributions.