Scattering of narrow band noise by slowly moving body in the ocean

Narrowband high frequency sound scattering intensities for a moving sphere surface and for adjacent flow inhomogeneities are estimated independently in the problem of moving sphere sound scattering. It is shown that due to the nonmonochromaticity of the incident sound field the observability of the conventional scattering picture could be substantially spoiled, even for an immobile scatterer. Unlike sphere surface flow scattering, for instance, potential flow is proven to lessen the harmful nonmonochromaticity influence with the incident field bandwidth increase in a way that flow scattering yield is underlined. An even more substantial contribution to the total high frequency scattered field in the shadow field region is predicted for adjacent flows with nonzero vorticity. Scattering intensity calculations are accompanied by cross-section estimates for the narrow band uniform sound field spectra shape based on optics theorem