Relative cyclic component mode synthesis and its application to nonlinear vibration analysis of mistuned bladed disks with friction joints

A new reduced order modelling technique based on Relative Cyclic Component Mode Synthesis (RCCMS) is presented. RCCMS results in an efficient and highly compact reduced-order model (ROM) suitable for nonlinear forced response analysis of mistuned bladed disk with friction interfaces. Implementation of relative coordinates not only reduces the computational time but also enhances the CB-CMS basis by incorporating the fully stuck modeshapes. In the proposed ROM, it is possible to introduce the small sector-level mistuning directly into the reduced model. In this way, reduction is performed only once in case of multiple analyses, necessary for statistical characterization of the nonlinear response levels of the system. Numerical simulations revealed a very good accuracy between the ROM and the baseline for nonlinear forced response analysis of a mistuned bladed disks.