A reduced-order cutFEM approach to model complex moving sound sources

Abstract

While traditional finite element based vibro-acoustic analysis of structures is done on stationary structures, in many occasions the structure under investigation is actually moving. To perform accurate finite element analysis on the vibro-acoustic performance of such structures requires the evaluation of a time-varying system, leading to several challenges. Of paramount importance are a strategy to update the mesh to the new configuration and an adequate time integration scheme that does not introduce large numerical artifacts. Additionally, the time-varying nature leads to an increase in computational complexity. In this paper a modeling strategy based on cut finite elements (cutFEM) is introduced that aims to tackle these challenges. The cutFEM approach can be seen as a fictitious domain approach in which the source is moving over a static mesh, cutting through elements where the actual source is located, using a level set description. The key advantage of this approach is that no remeshing and/or mesh morphing is required. It is shown how both implicit and explicit time integration schemes can be used to propagate the solution while the source is moving. Additionally, several model order reduction strategies are compared to speed up the online evaluation of the reduced order model.