A Hybrid FEM-SEA Approach for Fluid-Structure-Interaction in Acoustics

In the low frequency range (typically below 100 Hz) the Finite Element Method (FEM) is the current standard design tool for the prediction of structural vibration and the sound pressure in the adjacent fluid. The Statistical Energy Analysis (SEA) is appropriate for the high frequency range. However this method requires a sufficiently high modal density of both the structure and the fluid. The method is very effective if the system’s behavior is dominated by resonant vibrations. In the frequency range, where this requirement in some components still is not fulfilled which is between 100 Hz and 800 Hz in automotive design for example, both approaches are unable to provide realistic predictions. This paper introduces the so called SEA-like approach in which an inverse SEA model is derived from FEM. The implementation into the ANSYS® simulation environment is presented using a simplified vehicle model as an academic example. The approach combines the advantages and avoids the disadvantages of both FEM and SEA.     «

In the low frequency range (typically below 100 Hz) the Finite Element Method (FEM) is the current standard design tool for the prediction of structural vibration and the sound pressure in the adjacent fluid. The Statistical Energy Analysis (SEA) is appropriate for the high frequency range. However this method requires a sufficiently high modal density of both the structure and the fluid. The method is very effective if the system’s behavior is dominated by resonant vibrations. In the frequency...     »