部件性能非确定性对涡轴发动机性能影响量化方法研究

Quantification Method of Effects of Uncertainty on Component Performance for Turbo-Shaft Engine Performance

关键词:  涡轴发动机  性能  非确定性  概率设计

Key words:  Turbo-shaft engine  Performance  Uncertainty  Probabilistic design

摘要:

航空发动机各部件性能非确定性的累积叠加会导致发动机总体性能的非确定性。建立了基于蒙特卡洛概率设计方法的非确定性涡轴发动机数学模型，用以量化发动机各部件性能的非确定性对发动机性能的影响。结果表明:各部件性能按正态分布进行非确定性变化时对发动机性能有明显影响，与发动机确定性模型所计算的性能100%达标相比，输出功率的达标概率为49.32%，耗油率的达标概率为50.83%，模型量化结果合理且均方根误差小于3%。发动机在采用限制涡轮前温度的控制规律后，输出功率和耗油率的达标概率进一步降低。

Abstract:

The cumulative effect of uncertainty in engine component performance may stack up to affect the engine overall performance. In order to quantify the impact of uncertainty in engine component performance on turbo-shaft engine performance，a probabilistic model of turbo-shaft engine based on Monte-Carlo probabilistic design method was implemented. Results show，uncertainty of normal distribution in component performance has an obvious impact on the engine performance prediction. Compared with the calculation results of engine performance 100% meeting the targets utilized the deterministic engine performance model，the probability of the engine output power meeting the target is 49.32% and the probability of the engine SFC meeting the target is 50.83%. The calculated results of the model are reasonable and the root-mean-square error is less than 3%. Under employing the control law with limiting the turbine inlet temperature，the probabilities of the engine output power and SFC meeting the target further decrease.