Numerical Modeling and Experimental Identification of Mistuned Multi-Stage Bladed Assemblies

In turbomachinery, low pressure compressors are composed of a succession of bladed disks. To reduce the mass and increase the performance of the aircraft engines, one-piece multi-stage units of bladed disks have been recently developed. But these one-piece technologies are challenging for the mechanical design due to exacerbated effects of mistuning (i.e., mode localization and forced response amplification). In the thesis, an experimental method for the identification of mistuning in multi-stage bladed structures is proposed and validated. Numerical modeling methods are proposed to reduce computational times for the statistical predictions of the forced response amplification. A characterization of the interstage coupling is performed and a criterion is proposed to predict in advance if a multi-stage analysis is necessary.