Estimation of Forcing Function, Mistuning, and Modal Damping in a Bladed Rotor

摘要

Unscented Kalman filter has been successfully used to estimate damping, mistuning, and forcing functions. It has been shown that steady-state data are sufficient to get good estimates of mistuning and damping when both the steady-state output vibration data at a single frequency and forcing functions are known. When the forcing data are unavailable, however, alternate approaches are needed. It is shown that forcing function, mistuning, and damping can be simultaneously estimated from the transient vibration data.Numerical results are presented for a basic model of a mistuned bladed rotor with ten blades. The estimates of mistuning, damping, and forcing functions across trials with similar settings are precise, that is, the standard deviations are low compared to the mean of the estimates. Also, computation time required on a typical laptop computer is small. Future work will include the application of this technique to the multifamily reduced-order model developed on the basis of a finite element model as described in Ref.