Rub-impact fault vibration analysis of rotor system with the different parameters using Hilbert-Huang transform

The vibration characteristics of a rub-impact rotor system with different parameters are investigated using Hil-bert-Huang Transform (HHT)-a relative novel time-frequency analysis method. Firstly, the rotor with rub-impact at fixed limiter is modeled by finite element method (FEM). Then, system simulation signals at different rotating speeds, rub-impact clearances and rub-impact rod stiffness are obtained based on the FE model, moreover which are analyzed by using HHT along with Fast Fourier Transform (FFT) and shaft center orbit methods. The results show that the effects of variables on system motion patterns, response properties and rub-impact severity differ in degrees. Some conclusions are achieved which may be useful to detect rub-impact fault accurately and effectively.