Underwater acoustic scattering from a radially layered cylindrical obstacle in a 3D ocean waveguide |
| |
Authors: | AM Prospathopoulos GA Athanassoulis KA Belibassakis |
| |
Institution: | 1. Hellenic Centre for Marine Research, Institute of Oceanography, 46.7 Km Athens-Sounio Avenue, P.O. Box 712, 190 13 Anavyssos, Greece;2. National Technical University of Athens, School of Naval Architecture and Marine Engineering, Section of Ship and Marine Hydrodynamics, Heroon Polytechniou 9, 157 73 Athens, Greece;3. Department of Naval Architecture, Technological Educational Institute of Athens, 122 10 Athens, Greece |
| |
Abstract: | A solution based on coupled mode expansions is presented for the 3D problem of acoustic scattering from a radially layered penetrable cylindrical obstacle in a shallow-water plane-horizontal waveguide. Each cylindrical ring is characterized by a general, vertical sound speed and density profile (ssdp), the ocean environment around the obstacle can be also considered horizontally stratified with a depth-arbitrary ssdp, and the bottom is assumed to be rigid. The total acoustic field generated by an harmonic point source is represented as a normal-mode series expansion. The expansion coefficients are calculated exploiting the matching conditions at the cylindrical interfaces, which results in an infinite linear system. The system is appropriately truncated and numerically solved by using a recursive relation, which involves the unknown coefficients of two successive rings. Results concerning the transmission loss outside and inside obstacles consisting of three cylindrical rings are given for a typical depth-dependent ocean sound-speed profile. The presented solution can serve as a benchmark solution to the general problem of 3D acoustic scattering from axisymmetric inhomogeneities in ocean waveguides at low frequencies. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|