Modelling and analysis of a bladed drum subject to the Coriolis and mistuning effects

The interaction between the Coriolis and mistuning effects on a finite-element model (FEM) of a simplified bladed drum compressor has been investigated in this paper. The Subset of Nominal Modes (SNM), the Component Mode Mistuning (CMM) and the Integral Mode Mistuning (IMM) techniques have been chosen and adapted to consider the reduction of the Coriolis matrix. Both free and forced responses of the ROMs have been validated using the FEM solutions as the benchmark. A new analysis using Monte Carlo simulations has been performed to consider disc and blade mistuning independently, and to study the domination of one over the other. The impact of the Coriolis effect has been highlighted through observation of the model with and without the Coriolis matrix. The evolution of the global dynamic behaviour with rotational speed has been investigated for the first time for different excitation frequencies and engine orders (EO). This in-depth investigation of a blisk allowed a better understanding of the interaction between the Coriolis and mistuning effects. The blade-dominated responses and the modes which remain close to the veering regions have strong mistuning effects, with significant localisation and amplitude magnification. The results mainly highlight that the disc-dominated and the blade-disc responses tend towards a tuned behaviour with the appearance of travelling waves.

Automated summary

The interaction between the Coriolis and mistuning effects on a finite-element model of a simplified bladed drum compressor was investigated in this paper. The impact of the Coriolis effect was highlighted, and the global dynamic behavior with rotational speed was studied for different excitation frequencies and engine orders. A better understanding of the interaction between the Coriolis and mistuning effects was achieved through in-depth investigation of the blisk. The results showed strong mistuning effects and the appearance of traveling waves in blade-dominated responses and modes close to the veering regions.