航空发动机可靠性评估中故障样本时效性分析

通过故障数据建立可靠性模型反映系统可靠性状态的变化具有一定的滞后性,随着发动机可靠性水平的不断提高,对航空发动机进行可靠性评估需要将早期故障样本进行时效性处理.提出衰减因子 α 用于表示故障强度的衰弱程度,对Gompertz可靠性增长模型改进得到故障的衰减函数,来描述故障强度的衰弱过程;用Bayes方法合理利用发动机全部故障样本进行数据融合,可有效解决样本的时效性问题.对在研的某涡扇发动机进行故障统计分析,研究了典型故障模式的时效性变化,结果表明:考虑样本的时效性后进行可靠性评估对发动机当前的可靠性水平能给予更加科学的评价.

Time effectiveness analysis of fault samples for aero-engine reliability assessment

It is hysteretic to use reliability model which is set up based on failure data to reflect the changes of system reliability condition. With the enhancement of reliability level, the early failure samples should be processed time effectively in aero-engine reliability assessment. An attenuation factor α was proposed to express the attenuation grade of failure intensity. The attenuation function that describes the attenuation process was captured by improving Gompertz reliability growth model. All useful information was utilized by using Bayes data fusion methods for time effectiveness of samples. A new acquisition turbo-fan engine was statistically analyzed by this model, and the time effectiveness of fault samples for typical failure was studied. The result indicates that this model could provide more scientific evaluation of aero-engine-s reliability.