Patch Transfer Function (PTF) : a substructuring approach for linear acoustics
Résumé
For industrial structures, large acoustics problems like noise radiated by cars are very difficult to solve using classical methods like full BEM, because of the complexity of the structure. The coupling between FEM and BEM procedures and the ways to reduce calculation time have been developed from the 70's [1] and this is still a research area of first interest [2]. The PTF approach has been first presented in reference [3]: it considers several acoustic subsystems, which are analysed separately, considering each coupling area as a rigid surface, which is divided in elements called patches. For these calculations, any available method (FEM, BEM...) can be used in order to build a database of transfer functions between sources and patches, which are acoustic impedance transfer functions. Then, continuity relations can be written on the interface in order to couple the sub domains: this approach is close to the mobility and impedance concepts which are widely used in mechanics, it is based on linearity properties of acoustic phenomenon.