Sound scattering by a finite number of arbitrary scatterers has remained a complicated problems. For this reason, only limited numerical results have been documented in the literature. The main difficulty perhaps has been associated with the lack of efficient numerical algorithms and the limited computing capability. Among many useful formalisms suggested for describing sound scattering by a finite group of arbitrary scatterers, three approaches appear to be particularly useful, that is, the self-consistent approach [1, 2], the T -matrix method , and the method of moments .
The recent expanding capability of digital computers has in principle made it possible to compute the more complicated problem of multiple scattering from a finite number of scatterers. Following the self-consistent scheme in Foldy [1], the multiple scattering processes can be represented by a set of coupled linear equations. The solution to these equations can be obtained by a matrix inversion. Such a procedure has been used previously to investigate multiple scattering by isotropic scatterers, especially the acoustic localization in bubbly liquids in which air-filled bubbles are isotropic scatterers . The purpose of this paper is to generalize the numerical matrix method in Ye and Alvarez to more complicated cases involving many anisotropic scatterers. It will be clear from the derivation that the present approach can be used for scattering from many scatterers with arbitrary configurations for a wide range of situations. 231