Dual Craig-Bampton component mode synthesis method for model order reduction of nonclassically damped linear systems

The original dual Craig-Bampton method for reducing and successively coupling undamped substructured systems is extended to the case of arbitrary viscous damping. The reduction is based on the equations of motion in state-space representation and uses complex free interface normal modes, residual flexibility modes, and state-space rigid body modes. To couple the substructures in state-space representation, a dual coupling procedure based on the interface forces between adjacent substructures is used, which is novel compared to other methods commonly applying primal coupling procedures in state-space representation. The very good arbitrary viscous damping of the dual Craig-Bampton approach is demonstrated on a beam structure with localized dampers. The results are compared to a classical Craig-Bampton approach for damped systems showing the potential of the proposed method.