APPLICATION OF IMPROVED HYBRID INTERFACE SUBSTRUCTURE CMS METHOD IN THE MODAL ANALYSIS OF MISTUNED BLADED DISK ASSEMBLIES

To improve the efficiency of modal analysis for aeroengines of ensured computational accuracy, an improved hybrid interface substructure component modal synthesis (CMS) method is proposed to avoid massive calculation in traditional methods when the substructure is composited. The comprehensive model is further simplified and duel coordination conditions of displacement and force are introduced to ensure the accuracy of the calculation. The parametric model of the assembled structure of blades and disks is constructed to set up finite element models for each substructure, which are then synthesized using the coordination conditions of displacement and force to obtain modal frequencies. Compared with the overall structure finite element model, the computational time is reduced by 23.86%~35.74%, and the modal deviation is less than 0.57%, while the computational time was reduced by only 14.63%~29.20% and the modal deviation was less than 0.49% for traditional methods. Therefore, under the same working environment and to achieve the same level of computational accuracy, the proposed method is much more efficient than traditional methods, especially in the high order modal solution procedure. This study lays a solid foundation for further research on the dynamic responses of composite structures of the mistuned bladed disk assemblies for aeroengines.