Dynamics Analysis of a Double-Disk Rotor with Two Breathing Cracks Based on Finite Element Method

摘要

A finite element (FE) model of a rotating double-disc rotor with two breathing cracks is presented. A flexibility matrix for the transverse crack on the rotating shaft is obtained according to fracture mechanics. The breathing behavior of the crack is simulated by stress intensity factors of mode ?along the crack front. The numerical simulations are conducted to study the coupled vibrations of the rotor system. The effects of the crack depth and the crack angle on the vibration response are discussed. The results show that the amplitude of 1X component declines with the increase of the crack angle but increases with the crack depth increasing. The amplitude of 2X decreases with the increase of the crack angle before β = 90° but increases again later on. And it increases with the crack depth increasing. The amplitude of 3X with various crack angles and crack depths are not quite noticeable. The results of the paper may provide theory references to crack detection and identification.