No abstract

No abstract

No abstract

No abstract

An advanced boundary element/fast Fourier transform (BE/FFT) methodology for solving axisymmetric acoustic wave scattering and radiation problems with non-axisymmetric boundary conditions is reported. The boundary quantities of the problem are expanded in complex Fourier series with respect to the circumferencial direction. Each of the expanding coefficients satisfies a surface integral equation which, due to axisymmetry, is reduced to a line integral along the surface generator of the body and an integral over the angle of revolution. The first integral is evaluated through Gauss quadrature by employing a two-dimensional boundary element methodology. The integration over the circumferencial direction is performed simultaneously for all the Fourier coefficients through the FFT. The singular and hyper-singular integrals are computed directly by employing highly accurate three-dimensional integration techniques. The accuracy of the proposed boundary element methodology is demonstrated by means of representative numerical examples.