Intermittent chaos and bifurcation in time domain of the response of cracked rotors

This paper derived dynamic equations of the Jeffcott cracked rotor, the cracked rotor with midspan and overhung disks and the cracked rotor supported on squeeze film dampers (SFD), and analyzed the intermittent chaos and the bifurcation in time domain of the response of the three kinds of cracked rotors. The results show that there exists obvious intermittent chaos in all cracked rotor systems and the bifurcation and chaos response is not only due to the variation of system parameters, but also due to the time varying. This also shows that the intermittent chaos is the random process of response entering and exiting chaos with time-varying parameters. The response routes to chaos are generally from period or quasi-period to intermittent chaos. The response amplitude will increase before chaos beginning. There exists in the response the doubling period bifurcation with time and sometimes the period-3 window.