ASA 124th Meeting New Orleans 1992 October

5pPA7. Acoustic image analysis of acoustic scattering from rigid spheroids and cylinders.

Charles F. Gaumond

Angie Sarkissian

Louis R. Dragonette

Naval Res. Lab., Washington, DC 20375-5000

Acoustic imaging can be used to display the spatial, frequency, and temporal effects of acoustic scattering. The quantitative images can be coupled with simple scattering models to elucidate scattering mechanisms. Acoustic scattering results are presented from rigid spheroids and spheroidally endcapped cylinders with similar length-to-width ratio. The bistatic patterns produced from end-ensonification differ due to the reflectivity of the ends and the amount of reradiation along the length of the scatterer. The ends of prolate spheroids possess higher curvature than endcapped cylinders and therefore reflect less into the back direction. The cylinders possess a straight section along which the creeping wave does not radiate. These scattering phenomena are shown in acoustic images formed from the far-field scattering patterns.