SPHERICAL WAVE SCATTERING BY SLENDER BODIES

The problem of the scattering of a spherical acoustic wave by rigid sl ender bodies of revolution is investigated theoretically from a formal ism based on the matched asymptotic expansions method. It is an extens ion of a formulation that was originally derived for incident plane wa ves with the so-called ''slender-body approximation.'' Simple and prac tical formulas are obtained for the scattered pressure in the near and far fields; they are valid at low and medium frequencies when the red uced wavenumber Ka is less or of the order of unity. The computations of the monostatic and bistatic angular distributions for a spheroid ar e presented to illustrate the sensitivity of the scattered field with respect to the distance source and observation point.