Accession Number : AD0431098

Title :   ON WAVE FRONTS AND BOUNDARY WAVES,

Corporate Author : WISCONSIN UNIV MADISON MATHEMATICS RESEARCH CENTER

Personal Author(s) : Duff,G. F. D.

Report Date : NOV 1963

Pagination or Media Count : 71

Abstract : For a scalar field governed by a linear hyperbolic partial differential equation with constant coefficients, the wave fronts and their singularities arising from a point source in space-time are studied. The calculus of distributions is employed to represent the elementary solution, and a method of stationary phase to describe asymptotically its singularities. The occurrence of coincident characteristic roots, giving rise to ruled surface singularities, is first considered. The main portion of the paper concerns the reflection of the waves at a plane boundary, where several further types of waves can arise. Head waves and branch waves arise from branch points associated with real and complex normal roots. The Rayleigh and supersonic waves arise from poles of a certain boundary discriminant, and the latter type has an extended domain of dependence. (Author)

Descriptors :   (*WAVE PROPAGATION, PARTIAL DIFFERENTIAL EQUATIONS), BOUNDARY LAYER, REFLECTION, STATISTICAL MECHANICS, ELECTROMAGNETIC RADIATION, ACOUSTICS, WAVES

Distribution Statement : APPROVED FOR PUBLIC RELEASE