Identification of Noise Sources by Means of Inverse Finite Element Method

M. Weber[1], T. Kletschkowski[1], and B. Samtleben[2]
[1]Helmut-Schmidt-University Hamburg, Germany
[2]Airbus Germany
Published in 2008

An inverse finite element method for noise source identification in an aircraft cabin is presented. If all sound sources are located on the boundary of the cabin, the equation system resulting from a matching FE model can be re-sorted in such a way that computation of the unknown boundary data is possible from measurement data taken in the cavity. The method is first validated using a simplified 3D COMSOL model. The numerically calculated data inside an inner sub-domain are impinged with a stochastic error and used as simulated measurement data to re-calculate the boundary data.  In a next step, the sound field in the cavity of an aircraft mock-up excited by both interior and exterior noise sources is mapped with a custom-built microphone array. A matching COMSOL model is verified and compared to the mapping data. Consequently, the inverse calculation is performed for this more realistic model.

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