关键词: 涡轮盘;疲劳(力学);可靠性分析;响应面法+;蒙特卡洛法

Abstract: A probabilistic model based on strain-life curve was developed to assess fatigue life reliability of a disk. By randomizing the Coffin-Monson equation with two related random variables. The square sum of residuals for linear regression of strain-life curve was redefined. In this way, the parameters obtained from regression will be unchanged when the coordinate system is changed. The strain amplitude distribution at a critical site of a disk was acquired through the combination of response surface method and Monte Carlo simulation. Finally, the distribution of strain failure life at the site can be achieved by numerical simulation. And then the reliable life or the reliability for any given life can be derived easily from the distribution.

Key words: Turbine wheel;Fatigue(mechanics);Reliability analysis;Response surface method~+;Monte Carlo method