Robust optimization of dynamic vibration absorber array for vibration attenuation of mistuned bladed disk

Integral blisk is prone to large vibration amplitudes due to the low intrinsic damping level, especially for the mistuned cases. Dynamic vibration absorber array (DVAA) has been shown to be an effective vibration attenuation approach for blisk. Nevertheless, its performance tends to remarkably degrade at large mistuning conditions. Regarding this issue, an effective optimization approach is addressed to enhance the robustness of the performance of DVAA for mistuned blisk by introducing intentional deviation to the natural frequencies of the DVAs. A novel area-based index considering the random character of mistuning is developed for quantifying the robustness enhancement effectiveness. The Kriging surrogate model is utilized to establish a nonlinear mapping relationship between the index and the parameters of DVAA, and an iterative process is used to improve the optimization efficiency. Both a lumped parameter model and a finite element model of blisk are adopted to verify the presented approach. The results reveal that the optimized frequency parameter of DVAs can substantially improve vibration suppression performance at medium and large mistuning conditions while maintaining the performance at small mistuning. The proposed optimization approach can obviously enhance the robustness of vibration attenuation performance of DVAA for blisk with large mistuning levels.