Patch Transfer Function Approach for Analysis of Coupled Vibro-Acoustic Problems Involving Porous Materials 2014-01-2092
In many application fields, such as automotive and aerospace, the full FE Biot model has been widely applied to vibro-acoustics problems involving poro-elastic materials in order to predict their structural and acoustic performance. The main drawback of this approach is however the large computational burden and the uncertainty of the input data (Biot parameters) that may lead to less accurate prediction. In order to overcome these disadvantages industry is asking for more efficient techniques.
The vibro-acoustic behaviour of structures coupled with poroelastic trims and fluid cavities can be predicted by means of the Patch Transfer Function (PTF) approach. The PTF is a sub-structuring procedure that allows for coupling different sub-systems via impedance relations determined at their common interfaces. The coupling surfaces are discretised into elementary areas called patches.
Since the patch impedances can be determined in either computational or experimental manner, the PTF approach offers full modularity. For sub-systems, which allow for an efficient numerical characterisation, simulation schemes should be adopted, whereas for sub-systems, which involve high-complexity models, experimental measurement might be a cost-efficient alternative.
A novel experimental method for the characterisation of poroelastic materials is proposed and validated through an FE model. The novelty of the methodology proposed consists in the fact that the trim characterisation no longer relies on material micro-model (i.e. Biot), whose parameters are often difficult to be acquired.
Finally, the PTF approach proposed has been applied on a laboratory test case, consisting of a trimmed plate coupled to a rigid acoustic cavity. The PTF reconstruction has been successfully validated through a measurement conducted on the fully assembled system.
Citation: Veronesi, G., Albert, C., Nijman, E., Rejlek, J. et al., "Patch Transfer Function Approach for Analysis of Coupled Vibro-Acoustic Problems Involving Porous Materials," SAE Technical Paper 2014-01-2092, 2014, https://doi.org/10.4271/2014-01-2092. Download Citation
Giorgio Veronesi, Christopher Albert, Eugène Nijman, Jan Rejlek, Arnaud Bocquillet
Virtual Vehicle Competence Center, BMW Group
8th International Styrian Noise, Vibration & Harshness Congress: The European Automotive Noise Conference