共因失效相关同级叶片系统可靠性分析

为了准确地分析航空发动机的可靠性，针对航空发动机失效模式多、相关性复杂的特点，在考虑失效模式相关性的基础上，建立了共因失效相关的结构系统可靠性模型。采用蒙特卡罗法和近似数值分析法对航空发动机同级叶片系统在叶片静强度不足失效、叶片外缘变形碰摩失效及考虑2种失效模式下的可靠度进行了计算分析。分析表明与共因失效相关的可靠性模型相比，传统的不考虑失效模式相关性的可靠性模型使可靠度评估过于保守。近似数值分析法在保持与蒙特卡罗法计算精度相同的情况下，能够大幅提高计算效率。

Reliability analysis of same stage blade system with common failure dependence

Aeroengine has multiple failure modes and complex dependence. To precisely analyze the reliability of aeroengine, structural system reliability model with common cause failure dependence is established based on failure mode dependence. The Monte Carlo method and the approximate numerical analysis method are applied to compute the reliability of aeroengine's same stage blade system with insufficient blade static strength failure, with rub failure induced by blade outer margin deformation, and with both of the above two failures. Results show that the estimated reliability of the traditional reliability model without considering failure dependence is lower than that of the reliability model with common cause failure dependence. While maintaining the similar level of computational accuracy, the approximate numerical analysis method has much higher computational efficiency than the Monte Carlo method.