基于灰色理论的航空发动机可靠性指标评估方法

Evaluation Method on Reliability Index of Aero-Engine Based on Gray Theory

以层次分析理论为基础,采用二次分布和灰色理论综合评估方法,建立了航空发动机可靠性指标评估模型。将发动机可靠性指标分为总体级、危害度级、故障模式三个层次,故障模式级的数据融合采用二次分布和加权平均的方法,危害度级的数据融合采用层次分析-灰色理论综合评估方法,将航空发动机可靠性指标分散描述成属于不同灰类的向量,将评估灰类向量进行单值化处理得到发动机总体可靠性指标,实现了发动机可靠性指标从故障模式级到危害度级再到总体指标的逐步融合。对某型涡扇发动机应用表明,基于层次分析-灰色理论的评估模型应用范围广泛,对数据的分布类型不予限制,评估结构清晰,分层次反映了发动机的可靠性状态。

A reliability index evaluation model was built on hierarchy analysis process theory through an evaluation method of twice distribution algorithm and gray theory. By the method,reliability index were divided into three levels: general level,hazard level and failure model level. The data of failure model level were fused through twin-distribution and weighted average methods. That of hazard level were done through hierarchy analysis and gray theory. Index of general were fused by single value method on the output of hazard level which were different gray vectors. The model was used to evaluate one turbofan engine,and the results show that the index can reflex the reliability state of engine.