Computer Visualization of the Sound Source in a Shallow Waveguide

Chirov D. V.

The features of practical implementation of the holographic method of the acoustic field recovery in the space of the waveguide, which is the method of the matched field processing, as well as the theoretical basis of the method are considered in the article. The paper shows the relationship of characteristics of restored acoustic field of sound source with the complex transfer function of the wave-guide, which is determined on the basis of the solution of the wave equation. A simple recovery source field by applying computational procedures of calculating the transfer characteristics of the waveguide by a finite difference method for the explicit calculation scheme is noted. The results of computational experiments on the study of the effectiveness of the method in the conditions of an inhomogeneous underwater environment are presented. Each numerical experiment consisted of two stages: calculation of the hologram field of a point source of a sound and subsequent recovery of the acoustic field. For computational experiments a shallow waveguide with a flat bottom and with a positive acoustic refraction of the rays from the surface to the bottom was selected. In the paper three simplified models of inhomogeneous underwater environment are considered: with small-scale turbulence, with internal wave, with a layered structure of the vertical distribution of sound velocity. It is shown that the unaccounted in homogeneities of the velocity of sound along the length of the waveguide have a material adverse effect on the efficiency of recovery of the field of a source of a sound by holographic method. This effect can be reduced by clarifying the parameters of the environment along the waveguide.

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