不确定条件下民航发动机维修工作范围决策

为降低民航发动机维修成本和提高修后性能,提出不确定条件下的发动机维修工作范围决策方法．将发动机各单元体各维修级别能够恢复的整机性能值表示为一个梯形模糊数,建立单元体性能恢复值分配优化的模糊机会约束规划模型;将模型的机会约束转化为清晰等价类,发现该模型和确定条件下的单元体性能恢复值分配优化模型具有相同的结构,能够采用确定条件下模型的求解方法进行求解;利用应用实例对提出方法进行了验证．结果表明:提出方法能够解决不确定条件下的发动机维修工作范围决策问题;模型机会约束的置信水平对决策结果至关重要,要综合考虑实现送修目标的风险和维修成本,确定合理的置信水平．

Civil aeroengine workscope decision-making under uncertain conditions

To reduce maintenance cost and improve performance after a shop visit,a decision-making method for civil aeroengine workscope under uncertain condition is proposed.Firstly,aeroengine overall performance restoration value for each module′s maintenance level is expressed as a trapezoidal fuzzy number,and then a fuzzy chance constrained programming model on module performance restoration value distribution optimization is put forward under uncertain condition.Secondly,the chance constraint of the model is transformed into a clear equivalence class.It is found that this model and the optimization model of module performance restoration value distribution under certain condition have the same structure.Thus,the solving method of the model with certain condition is adopted to achieve the model with uncertainty condition.Finally,the proposed method is validated by a real example.The result shows that the proposed method can solve decision-making problem for aeroengine maintenance workscope under uncertainty condition;the reasonable confidence level for the chance constraint of the model is essential to the decision-making result,and could be determined according to the risk of achieving the repair objectives and maintenance cost.