A reduced order model based on sector mistuning for the dynamic analysis of mistuned bladed disks

In this paper, a pre-existing reduction technique suitable for the analysis of mistuned bladed disk dynamics, the Component Mistuning Model technique (CMM), originally developed exclusively for the use of blade frequency mistuning pattern, is improved in order to allow for the introduction of a sector frequency mistuning pattern. If either mistuning is not confined to the blades (i.e. blades-to-disk interface mistuning), or the blades cannot be removed from the bladed disk (i.e. integral bladed disks), sector mistuning rather than blade mistuning is a more suitable choice to perturb the tuned system. The new version of the original technique is referred as CMM Upgrade (CMMU). After a theory review of the original technique, the modifications leading to the CMMU are described. Finally the proposed CMMU technique is validated in terms of both modal parameters estimation and forced response calculation, by means of a dummy bladed disk developed at Politecnico di Torino.