Fatigue Resistance Evaluation and Crack Kinetics Study for Aero Engine Fan Blades under Random Vibration

摘要

Various types of violent random vibration of aero engine fan blades were investigated. Technique for random fatigue resistance evaluation of the blades has been developed which is based on the relation obtained between amplitude of equivalent sinusoidal stresses, parameters of random stress envelope, and data of conventional constant amplitude tests. Experimental validation of the technique has been carried out on the base of comparison between the calculated and experimental values of equivalent amplitude. For this purpose fatigue tests were performed in the course of which the features of intense service random vibration of the blades were simulated. Some peculiarities of fatigue crack kinetics under random loading were studied.