A component mode synthesis based hybrid method for the dynamic analysis of complex systems

A hybrid method is presented for predicting the dynamic response of complex systems across a broad frequency range. In the mid-frequency range it is quite common to find a mixture of long wavelength motion, global modes, which spans several sub-structures, together with weakly phase correlated local motion, local modes, that is confined to individual sub-structures. In this work, the use of a Component Mode Synthesis allows us to relate Finite Element Method sub-structuring with the modes location within the different sub-structures defined in a Statistical Energy Analysis model. The method proposed here, the Hybrid Analysis based on Component Mode Synthesis sub-structuring (HA-CMS) method provides a greater flexibility defining the applicability range of each one of the calculation methods. Deterministic description of the global behaviour of the system is combined with a statistical description of the local one, taking into account the energy transfer between global and local scales. The application of the HA-CMS method is illustrated with a numerical validation example.