航空发动机结构可靠性多元建模及仿真理论与方法研究

项目名称： 航空发动机结构可靠性多元建模及仿真理论与方法研究

项目编号： No.51335003

项目类型： 重点项目

立项/批准年度： 2014

项目学科： 机械、仪表工业

项目作者： 谢里阳

作者单位： 东北大学

项目金额： 375万元

中文摘要： 传统疲劳理论缺乏统一处理多机理耦合、多部位损伤及多构件关联的方法，传统可靠性模型未能全面反映载荷历史、强度退化、结构特征等要素。针对航空发动机及其关键零部件疲劳可靠性设计与评估，研究载荷历程不确定性分层表征方式、低周-高周-超高周疲劳三种失效机理之间的相互作用和概率竞争关系、广布损伤结构的尺度效应、复杂载荷历程下的强度退化统计规律等，在概率框架下统一处理多部位、多机理疲劳问题，实现不同失效机理疲劳损伤演化和寿命预测模型的统一及可靠性模型的统一。基于系统论思想，借助多层统计分析等数学工具和随机事件之间的条件独立原理，立足于对失效机理和失效模式的科学表述，创新系统可靠性建模途径，建立统一表达多影响因素、多失效模式复杂零部件及系统的多元可靠性模型，发展仿真技术，精确反映可靠性的时间属性（载荷统计风险效应、部件性能退化）、空间属性（载荷宏观不确定性、部件结构特征）和关联属性（失效相关性）。

中文关键词： 多元可靠性模型;随机载荷历程;超高周疲劳;概率动力学响应;可靠性仿真

英文摘要： Traditional fatigue design theory cannot uniformly deal with low cycle, high cycle and super high cycle fatigue mechanisms as well as multiple site damage and multiple part correlation, traditional reliability model fails to completely reflect the effect of complicated random load history, strength degradation and structure geometry..Focused on the fatigue reliability design and evaluation of the mechanical components and system of aeronautical engine, the present proposal researches the way to characterize the uncertainty of complex load history hierarchically to support time-dependent fatigue reliability modeling, investigates the interaction and probabilistic competition among low cycle fatigue, high cycle fatigue and super high cycle fatigue, studies the size effect of wide spread damage part and the stochastic behavior of strength degradation under complex load history, systematically deals with complicated engine part fatigue problem involving multi-site damage, multiple failure mechanisms and multiple failure modes within the framework of probability theory, and builds universal fatigue damage evolution model, fatigue life prediction model and time-dependent reliability model which can take into account the different fatigue mechanisms completely and uniformly..Proceeding from system engineering point of view, multi-level statistics principle and conditional independence concept, based on the comprehensive description to the interaction among different failure mechanisms as well as the probabilistic competition relationship between different failure modes, innovates multi-mode fatigue reliability modeling methodology, constructs multi-variate reliability model and simulation approach for complex mechanical parts concerning multiple failure modes, accurately expresses the time-dependent issues (i.e. the statistical risk effect of load history, material strength degradation), spatial issues (load uncertainty in macro level and part geometry), as well as the emergency (statistical dependence among different failure sites and/or different failure mechanisms) of the reliability of aero engine parts and system.

英文关键词： Multi-variate reliability;random load history;super high cycle fatigue;Probabilistic dynamics;reliability simulation