涡轮叶片疲劳强度非概率可靠性模型

Non-probabilistic Stress-fatigue Strength Reliability Model for Turbine Blade

指出了Ben-Haim所提出非概率可靠性模型的不足并对其进行了改进,引入失效域边界的info-gap(information gap)模型拓展了非概率可靠性模型的适用范围。结合等寿命疲劳曲线建立了涡轮叶片的疲劳强度非概率可靠性模型。新模型只需知道强度和应力参数的一般变化范围,不需要相应的概率密度函数,对统计数据量的要求明显低于概率可靠性模型,求解过程能直接考虑疲劳应力和强度参数的二维不确定性特征。算例显示了新方法有效性以及与概率可靠性方法的相容性。

The deficiency of the non-probabilistic reliability model proposed by Ben-Haim was discussed and modified.The non-probabilistic reliability model was improved by establishing info-gap（information gap） model with respect to the boundary of failure set.A non-probabilistic fatigue strength reliability model for turbine blade was established based on fatigue strength curves with constant life.The new model simply needs the variation ranges of the stress and strength parameters,the probability density function of parameters are not the necessary.The new model needs less statistic information than the probabilistic reliability models.The new model copes with the 2-demensional uncertainties of the parameters immediately.The numerical example shows the validity of the new model and its consistency with probabilistic fatigue strength reliability method.