NUMERICAL AND ASYMPTOTIC ANALYSIS OF DIFFRACTED WAVE-FIELDS

A boundary-integral element and explicit asymptotic solutions for the 2-D problem of diffraction of an SH wave by a wedge of arbitrary angle are presented. The asymptotic solution involves the Fresnel function and its derivative. The methods have been tested on wedges with obtuse and acute angles. For the obtuse wedge, the asymptotic solution is, i n general, consistent with the numerical solution. For the acute wedge , a correction term involving the diffraction coefficient should be ta ken into account. The derivatives of diffracted wave field with respec t to the coordinates of the diffracting edge and to the wedge angle we re computed. A strong dependence of the derivatives upon the source fr equency has been found.