压气机叶片加工误差影响不确定分析

Uncertainty analysis of machining error influence of compressor blade

为了正确评估加工误差的影响,提出了一种考虑加工误差大小、分布随机性的数值研究方法以实现叶片性能不确定性分析。采用NURBS(非均匀有理B样条)方法实现叶型参数化,通过检测及统计手段获取误差真实分布,运用蒙特卡洛模拟生成随机样本,并训练Kriging代理模型进行不确定性分析,得到了叶片加工误差对气动性能的影响。结果表明:加工误差对气动性能的影响与所处工况有关,最高使得损失增加0.853%;叶型性能对于吸力面表面型线更为敏感,在加工及检测过程应给予更高要求。

A numerical method was innovatively presented to achieve uncertainty quanti- fication of airfoil considering the randomness of distribution and magnitude of manufacturing error. Airfoil parameterization achieved by NURBS （non-uniform rational B-spline） method and random sample was generated by Monte Carlo method based on error detection and sta- tistics. And then the Kriging surrogate model was trained to get the influence of machining error on compressor performance. Result shows the influence of profile error is related to the working condition and the loss may increase by 0. 853% at most. Moreover, the aerodynamic performance is more sensitive to suction surface than to pressure surface. The conclusion can provide more reasonable machining technology requirement and criteria of blade evaluation.