WAVE-PROPAGATION IN CONNECTED WAVE-GUIDES OF VARYING CROSS-SECTION

The spectral element method is extended to problems involving arbitrar y non-uniform waveguides by introducing an approximate tapered element . The depth of the cross-section is assumed to vary linearly, thus all owing an arbitrary variation to be modelled as a collection of piece-w ise linear segments. The frequency dependent stiffness relation is est ablished using the displacement fields of the uniform deep waveguide ( both longitudinal and transverse) as the Ritz functions. The element i s verified by comparison with a 2-D finite element solution.