The scattering of the sound field by thin unclosed spherical shell and ellipsoid

In this paper the result of solution of the axisymmetric problem of the scattering of sound field by unclosed spherical shell and a soft prolate ellipsoid of rotation is presented. Spherical radiator is located in a thin unclosed spherical shell as the source of acoustic field. The equation of the spheroidal boundary is given in spherical coordinates. Scattered pressure field is expressed in terms of spherical wave functions. Using corresponding theorems of addition and assuming small eccentricity of ellipse, the solution of boundary value problem is reduced to solving dual equations with Legendre's polynomials, which are converted to infinite system of linear algebraic equations of the second kind with completely continuous operator. Numerical results are given for various values of the parameters of the problem.

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