A Trefftz-based prediction technique for multi-domain steady-state acoustic problems

The finite element method and the boundary element method are the most commonly used methods for analyzing steady-state acoustic problems. Both methods are limited to low-frequency applications due to their increasing computational load for increasing frequency. Recently, a new wave based prediction technique has been developed based on the indirect Trefftz approach. Its enhanced computational efficiency allows to handle problems also at higher frequencies. A sufficient, but not necessary, condition for convergence of the novel method is that the acoustic problem domain is convex. Non-convex domains have to be partitioned into a number of (convex) subdomains. At the interfaces between subdomains, specific coupling conditions have to be imposed. This paper discusses various coupling conditions and their resulting convergence rate and involved computational load.status: publishe