基于随机有限元—一次二阶矩法的汽轮机叶片可靠度计算

Reliability calculation of steam turbine blade based on SFEM and mean-variance method

针对汽轮机叶片在工作中诸多参数的不确定性,通过建立叶片的力学模型,将随机有限元和一次二阶矩法相结合,对其进行了可靠度计算,并将随机有限元法的计算结果与解析法和 Monte Carlo 法进行了比较,证明了随机有限元法的正确性。对叶片的可靠度分析表明:当不能用解析法得到载荷响应,且载荷响应的概率密度函数无法得到时,采用随机有限元— 一次二阶矩法对结构进行可靠性分析是一种便捷方法。

Considering the uncertainty of influencing parameters in steam turbine blade operation, the reliability of steam turbine blade is obtained by creating its mechanical model and combining Stochastic Finite Element Method SFEM) with the mean-variance method. Comparison among SFEM, the available theoretical method ( and theMonte-Carlo method proves the validity of SFEM. Theblade reliability analysis shows that thecombination of SFEM and the mean-variance method is better in the case that the load response can't be obtained with the available theoretical method and also its probability density function is unavailable.