On the computation of dispersion curves for axisymmetric elastic waveguides using the Scaled Boundary Finite Element Method

• We present an approach to compute dispersion curves of elastic waveguides.
• The formulation is based on the Scaled Boundary Finite Element Method.
• Only propagating modes are traced selectively and computed by inverse iteration.
• The proposed approach is highly efficient compared to previous formulations.

In this paper we propose an algorithm to compute specific parts of the dispersion curves for elastic waveguides. The formulation is based on an axisymmetric representation of the Scaled Boundary Finite Element Method, where the wavenumbers of propagating modes are obtained as solutions of a Hamiltonian eigenvalue problem. The novel solution procedure involves tracing selected modes over a given frequency range and computing the corresponding solutions by means of inverse iteration. The resulting algorithm is applied in the context of material characterization, where the efficiency of the computation is crucial.