THEORETICAL AND EXPERIMENTAL-STUDY OF THE ACOUSTIC SCATTERING FROM SPHERICAL-SHELLS

This work is concerned with the acoustic interaction between two ident ical spherical elastic shells irradiated by a plane wave at arbitrary incidence. The study comprises both theoretical and experimental point s of view, in such a way as to permit the verification by the experime ntal results of the hypotheses constructed by the theoretical calculat ions. Of interest, of a given direction of incidence, is the mutual in teraction of the two targets as a function of their separation; and al so, for a given separation, the influence of the angle of incidence on the backscattered field. The theoretical approach uses an approximate formulation which consists in assuming that the targets are in each o ther's far fields. The results obtained have been verified by experime ntation on spherical shells of nickel molybdenum with b/a = 0.96 (b is the internal radius, and a is the external radius).