Hybrid FEA-SEA Modeling Approach for Vehicle Transfer Function

Finite element analysis (FEA) is commonly used in the automotive industry to predict low frequency NVH behavior (<150 Hz) of structures. Also, statistical energy analysis (SEA) framework is used to predict high frequency (>400 Hz) noise transmission from the source space to the receiver space. A comprehensive approach addressing the entire spectrum (>20 Hz) by taking into account structure-borne and air-borne paths is not commonplace.

In the works leading up to this paper a hybrid methodology was employed to predict structure-borne and air-borne transfer functions up to 1000 Hz by combining FEA and SEA. The dash panel was represented by FE structural subsystems and the noise control treatments (NCTs) and the pass-throughs were characterized via testing to limit uncertainty in modeling. The rest of the structure and the fluid spaces were characterized as SEA subsystems. The simulation and validation tests were performed on a single source input representing the air induction system (AIS).

Sound transmission loss (STL) and vibration transfer mobility (v/F) metrics were used for correlating the model against the test data. The model was able to predict accurately the transfer functions for various measurement conditions. Future work is planned to analyze coupling loss factors across critical hybrid-junctions and expand the analysis to multiple source inputs.