航空发动机可靠寿命消耗评估方法

Reliable Life Consumption Assessment Methods for Aero-engine

针对航空发动机零件受到疲劳蠕变作用的情况,提出一种航空发动机可靠寿命消耗评估方法。首先建立了一种航空发动机零件可靠寿命评估的加速系数方法,可以将试验载荷谱下的可靠寿命高精度地转换为标准循环和实际使用载荷下的可靠寿命。然后提出了一种疲劳蠕变损伤相加模型的修正系数,能够对模型中未考虑耦合作用项而带来的误差进行修正,从而可以对零件的可靠寿命消耗百分比单侧置信上限进行高精度评估,并且还可将其转换为标准循环和试验载荷谱上消耗的循环数,能够更加精准地对零件进行单机寿命监控和在线寿命管理。此外,本文方法也适用于燃气轮机、压力容器等其他产品的可靠寿命消耗评估和寿命管理。

The reliable life consumption assessment methods are proposed for the aero-engine components subjected to fatigue and creep.Firstly,a reliable life acceleration factor assessment method is established,by which the component’s reliable life under test load spectrum can be converted to the reliable life under standard cycle and actual service loads with high precision.And then,a correction factor for the fatigue-creep damage additive model is proposed and it can correct the model error caused by ignoring the coupling action term in the model.On this basis,the upper confidence limits of the component’s reliable life consumption percentages can be evaluated precisely,and they can also be converted to the cycle number consumed on standard load and test load spectrum.By the proposed methods,the component’s individual life monitoring and online life management can be realized more accurately.Moreover,the methods can also be applied to the individual monitoring and online life management of other products such as gas turbine and pressure vessel.