E. L. Shenderov
``Morfizpribor,'' Res. and Develop. Inst., 46. Chkalovsky pr., St. Petersburg, 197376, Russia
The theoretical investigation of scattering underwater sound waves by algae has been performed. The dependencies of sound level in the reflection waves upon parameters of the algae (sizes, biomass) are determined. For this purpose physical models corresponding to the typical kinds of the algae are developed. Scattering of sound by the algae are considered as the diffraction of the sound wave on the random set of the three-dimensional curved elastic bodies. By solving Helmholtz equation for the definite boundary conditions on the surface of the bodies, sound pressure in the waves scattered by the acoustic semi-transparent curved plates and rods corresponding to the plates and stems of the algae are computed. The obtained results can be used for the development of hydroacoustic methods of investigation of the continental shelf and also for reconnaissance of the algae abundance.