考虑尺寸效应的轮盘应力疲劳概率寿命分析方法

针对基于应变寿命模型的体方法对中、长寿命轮盘及模拟件寿命预测精度不准的缺陷,提出了考虑尺寸效应基于应力寿命模型的体方法,将最大应力比作为寿命可靠性计算的一个参数.对轮盘模拟试件进行了考虑尺寸效应的疲劳寿命可靠性分析,计算概率寿命与试验中值寿命相差14%,吻合良好.而传统的应变寿命点方法中值寿命预计结果误差达15倍之多....

Analysis method for the stress fatigue probability life of a disk considering size effect

Considering the flaw of precision in forecasting the medium-long and long life of disks and simulation specimen with volume method based on the strain life model, volume method based on the stress life model was proposed to compute the life of disks, which considered the size effect. The maximum stress and stress ratio have been taken into the life reliability computation of the disk as parameters. Then the fatigue life reliability of a disk simulation specimen was analyzed by the method given. The difference between computational median life in the method and the experimental median life is only 14%, and they fit well with each other. While the computational median life in the strain based method is only sixteenth of the experimental median life. It is shown that volume method based on the stress life model which considering the size effect can be used to estimate the probabilistic life of the medium-long and long life of disks and simulation specimen.