Stable model order reduction for time-domain exterior vibro-acoustic finite element simulations
Computer Methods in Applied Mechanics and Engineering
Finite element analyses of vibro-acoustic systems are usually performed in the frequency domain, meaning that the obtained results cannot straightforwardly handle time-varying input signals. These limitations can be overcome by performing a time domain analysis of the finite element model. To reduce the calculation complexity needed for time integration a model order reduction technique is proposed. A time stable Krylov subspace reduction technique is derived for the coupled exterior
... tic problem case. The Sommerfeld radiation condition is taken into account by applying infinite elements on the boundary of the mesh. The application of time stable infinite elements leads to a potentially singular mass matrix. A method is developed that circumvents mass matrix inversion, which is based on a singular value decomposition. Combined with a special formulation of the system matrices, the proposed method is shown to preserve the stability of the full model. The resulting model order reduction procedure is applied on a numerical model of a loudspeaker.