Design of low cycle fatigue simulating specimen for bolt holes of a turbofan engine high pressure turbine disc

Basic criterion of low cycle fatigue simulating specimen design was proposed based on the theory of tensile strain energy life prediction model. Simulating specimen for bolt holes of a turbofan engine high pressure turbine disc was optimized in design while comprehensively considering the ability of the test machine, thread connection strength and required number of bank disc. The optimizing objectives were as follows: the distribution of the first principal stress and strain within 0.8mm on the virtuak crack of the simulating specimen was consistent with the real bolt holes, and the ratio of the second principal stress to the first principal stress at the maximum stress point of the simulating specimen was consistent with the real bolt holes. Elastic plastic analysis was conducted to check the stress/strain consistency. The difference between safe life obtained by simulating specimen test and real turbine disc test was 4.48%.