Scattering of spherical impulses by slightly rough interfaces

Abstract

The effect of multiple coherent acoustical scattering by a perfectly rigid, slightly rough surface can be represented by a “small roughness” boundary condition due to Biot. Using normal coordinates, this allows one to obtain simple, closed form solutions for the scattering of spherical impulses, for either isotropic or anisotropic surface roughness [I. Tolstoy, J. Acoust. Soc. Am. (in press)]. These results can be extended to the case of rough interfaces between media of different densities. Of particular interest here is the possibility of a boundary—or surface—wave travelling along the interface, and of amplitude proportional to the logarithmic density increment between the media. [Work supported by ONR.]