使用条件对民航发动机涡轮叶片蠕变寿命的影响分析

Impacts of Operating and Health Conditions on Civil Aircraft Engine Turbine Blade Creep Life

发动机使用条件及自身健康状况对涡轮叶片的实际使用寿命有重要影响。以民航发动机为对象,借助发动机性能仿真模型和拉森-米勒蠕变寿命预测模型,研究了发动机性能退化、大气温度变化以及减推力起飞对涡轮叶片蠕变寿命的影响。通过仿真实验研究发现:发动机性能衰退加速了涡轮叶片的寿命损耗,压气机效率损失3%即可导致涡轮叶片蠕变寿命减少80%;随大气温度的升高,涡轮叶片蠕变寿命呈指数规律递减;减推力起飞对涡轮叶片延寿效果比较明显,但随着推力的进一步减小,对涡轮叶片的延寿效果却不再显著。

The operating and health conditions of a gas turbine have a significant impacts on the in -service life of the turbine blade. Aiming at civil aircraft engine, using the engine performance model and the Larson-Miller creep life prediction model, this paper studied the impacts of the degradation of the engine, the atmospheric temperature and the reduced thrust takeoff on the turbine blade creep life. The simulation studies show that the degradation of the engine can accelerate the consumption of the blade creep life. 3% loss in the efficiency of the compressor will cause 80% decrease of the creep life of the blade. As the increase of the atmospheric temperature, the creep life of the blade will decrease exponentially. Reduced thrust takeoff can extend the life of the blade effectively, however as the takeoff thrust is further reduced, it has little effect on the extention of the blade life.