航空发动机主轴承使用状态寿命预测模型(英文)

航空发动机主轴承寿命的实际可靠预测对于发动机的安全运行至关重要。使用状态寿命(即状态良好、初始损伤、故障发展和即将失效4个寿命阶段)描述航空发动机主轴承的使用寿命,并提出了一种基于支持向量机和模糊逻辑推理的主轴承状态寿命分析模型。首先,讨论了理论计算模型,采用轴承疲劳累积损伤模型,利用修正的Lundberg-Palmgren模型,结合飞参记录数据计算主轴承装机以来的累积寿命消耗,确定状态寿命的理论值。然后,详细阐述了状态寿命评估模型,该方法通过选取轴承振动的时域、频域统计量作为特征矢量,利用支持向量机作为辨识算法进行滚动轴承状态寿命的智能评估。最后,基于模糊逻辑推理融合主轴承状态寿命的理论计算模型和状态寿命评估模型得到主轴承状态寿命模型。采用滚动轴承的全寿命试验验证模型的有效性和可行性。

GRADE-LIFE PROGNOSTIC MODEL OF AIRCRAFT ENGINE BEARING

Research on practical and verifiable prediction methods for the service life of bearings plays a critical role in improving the reliability and safety of aircraft engines.The concept of grade-life(GL)is introduced to describe the service life of bearings.A GL prognostic model for aircraft engine bearings is proposed based on support vector machine(SVM)and fuzzy logic inference.Firstly,the mathematical model is discussed to predict the physics-based GL(PGL).Then,the diagnostic estimation model based on SVM is presented in detail to predict the empirical GL(EPL).Thirdly,a fuzzy logic inference is adopted to fuse two GL predicted results.Finally,the GL prognostic model is verified by the run-to-failure data acquired from an accelerated life test of an aircraft bearing.The results show that the model provides a more practical and reliable prediction for the service life of bearings.