| Abstract: | Based on the simple hinge crack model and the local flexibility theorem, the corresponding dynamic equation of the cracked rotor is modelled, the numerical simulation solutions of the cracked rotor and the uncracked rotor are obtained. By the continuous wavelet time-frequency transform, the wavelet time-frequency properties of the uncracked rotor and the cracked rotor are discussed. A new detection algorithm that uses the wavelet time-frequency transform to identify the crack is proposed. The influence of the sampling frequency on the wavelet time-frequency transform is analyzed by the numerical simulation research. The valid sampling frequency is suggested. Experiments demonstrate the validity and availability of the proposed algorithm in identification of the cracked rotor for engineering practices. |
