Nonlinear response analysis of aero-engine rotor bearing rub-impact system caused by horizontal yawing maneuver load

Abstract

Based on the simplified aero-engine rotor system, a new nonlinear response prediction model of rotor bearing rub-impact system is established. Different from the traditional rotor system rub-impact model, based on the detailed characteristics of the blade–disc system, this paper considers the influence of the number of blades and the dynamic to static clearance on the rub-impact force. In addition, the influence of additional load on the established rotor-bearing system due to the change in the flight motion state of the horizontal yawing maneuver is also considered The Newmark-β numerical method is used to solve the system, and the effects of maneuver load and rub-impact stiffness on the nonlinear dynamics of the system are studied The results show that the system produces a kind of sub harmonic resonance rub-impact phenomenon, that is, the system will produce 1/2 sub harmonic resonance under the action of maneuver load near the double critical speed, which will increase the vibration response amplitude of the system. With the increase of maneuver load, the system always has complex nonlinear phenomenon; with the increase of rub-impact stiffness, the system produces a large number of frequency division and frequency multiplication components, which can be used as the characteristic frequency of rub-impact faults.