基于故障树的飞机结构腐蚀损伤模糊综合评判

Fuzzy comprehensive evaluation of corrosion damage of aircraft structures based on fault tree

针对飞机结构腐蚀损伤分析和评价过程中影响因素复杂且具有模糊性的问题,提出了基于故障树分析和模糊理论的方法对飞机结构在复杂环境下发生的腐蚀损伤进行综合评判.对飞机结构腐蚀损伤过程和机理进行分析,构建飞机结构腐蚀损伤故障树,建立腐蚀损伤影响因素的评判集;计算各评判因素的相对概率重要度,根据评判因素相对概率重要度的比重,建立评判因素权重集;确定飞机结构腐蚀损伤的评价集,建立从评判因素集到评价集的模糊映射;通过模糊关系的模糊变换,对服役环境引起飞机结构的腐蚀损伤进行定量评价.通过飞机铝合金结构和不锈钢结构在沿海环境条件下腐蚀损伤评判的实例分析,证明了该方法的有效性,可为飞机结构设计和维修提供依据.

To resolve the complexity and fuzziness of influence on the corrosion damage of aircraft structures,a method based on fault tree analysis and fuzzy theory was proposed to evaluate the corrosion damage of aircraft structures in complicated environments.Fault tree of corrosion damage on aircraft structures was set up by analysis of corrosion process and mechanism,and then the evaluation set of corrosion damage was obtained.Relative importance of evaluation factors was analyzed,and weight set was got by the proportion calculation of relative importance of evaluation factors.After the evaluation grade of corrosion damage has been set up,the fuzzy mapping between evaluation set and evaluation grade was set up.The corrosion damage of service environments on aircraft structures was evaluated quantitatively by fuzzy transformation of fuzzy relation.Finally,corrosion damage evaluations of aircraft aluminum alloy structures and stainless steel structures in coastal environments were illustrated,which demonstrate that the proposed method is valid and can provide evidence for the aircraft structural design and maintenance.