A probabilistic mistuning study is conducted to investigate the impact of Integrally Bladed Rotor (IBR) blend repair approaches to mistuned response amplification. A repair approach, or "blending," is a common method for repairing rotors with foreign object damage. Established blending limits, or maximum allowable blend geometries, are often based on a maximum allowable airfoil frequency deviations from its tuned counterpart without a necessary investigation of mistuned response amplification. This investigation is researched here by developing an automated probabilistic work-flow for blending airfoil geometries and predicting the mistuned response. To do this, a parametric blended airfoil model is created that provides airfoil leading edge blend geometries and finite element meshes. The resulting airfoil meshes are imported into efficient geometric mistuning reduced order model (ROM) software that predicts the mistuned IBR responses. Different test case IBRs are subject to a population of random blend geometries to provide a distribution of mistuned responses this is compared to the original, un-blended test case. The key focus areas are to: demonstrate the probabilistic work-flow; determine if blends provide larger risk of mistuned response amplification; and if there are best/worst airfoils to blend to increase/decrease forced response.
展开▼
