Transient spheroidal elements for unbounded wave problems

A wave-envelope element numerical scheme is applied to the solution of unbounded wave problems. The scheme is based on a Fourier transformation of a discrete model formulated in the frequency domain. This yields a discrete system of ordinary differential equations in time which are local in space. Oblate and prolate spheroidal element geometries are used. The accuracy of the scheme is demonstrated by a comparison of computed and analytic solutions for axisymmetric test cases. Time-harmonic and transient solution are presented. An indirect solution procedure is also presented which permits the sparsity of the transient equations to be utilised more effectively.

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