Research of the delaying crack propagation on an aero-engine rotor

Abstract

Due to the action of alternating loads, the micro defects of rotor's materials and the micro traumas in the mechanic processing would easily cause the crack propagation and even the catastrophic accidents. Vibration characteristics of the rotor system of an aero-engine, the crack's breathing states and breathing periods are investigated with different parameters including the rotational speed, the crack angles, the crack depth and nonlinear parameters. By comparing influences of the crack breathing states caused by changes of different parameters, the paper summarised the mutation regulations of the crack breathing states in the synchronous and verified the feasibility of the mechanism on delaying the crack propagation. The paper also proposed a novel method of the delaying crack propagation, in this method the electro-magnetic actuator (EMA) was used to realise the vibration controlling states and to delay crack propagation in the running process of the nonlinear cracked rotor in an aero-engine. The validity of the proposed method was verified through experiments.