A component mode selection method based on a consistent perturbation expansion of interface displacement

A mode selection method is presented for the reduced-order modeling (ROM) of structural systems in conjunction with the Craig-Bampton component mode synthesis technique. The proposed method is derived by using a consistent expansion of the interface displacement in terms of a frequency-dependent small parameter as applied to a Craig-Bampton-like ROM formulation. It is found that this procedure yields a coupling mechanism of the modes of the full model to those of substructures. The present mode selection method employs this coupling mechanism as an indicator, labeled as the CMSσ method, for the substructural modal contributions to the full model. The performance of the proposed method is demonstrated by various numerical examples and compared favorably with existing method such as the CMSχ method.