基于正交试验的压气机流动特性对转子叶尖关键几何参数敏感性研究

Sensitivity Study of Key Geometrical Parameters of Blade Tip on the Flow Characteristic of Transonic Rotor Based on Orthogonal Test

本文选取NASA Rotor37叶尖基元级的沿程曲率分布特征、吸力面最大厚度点相对位置、尾缘半径三个关键几何参数,采用正交试验方法设计了9组方案,详细分析各几何参数对压气机性能的影响程度和作用机制。结果表明,三种几何因素对转子等熵效率和总压比的影响不大,但对工作裕度的影响较为显著,且按照影响程度排序依次为:叶尖曲率分布特征、吸力面最大厚度点相对位置、叶尖尾缘半径。其中转子叶尖曲率分布特征的变化通过改变其叶尖流向载荷分布规律进而显著影响叶尖流场特性和工作裕度。结合叶尖基元级曲率分布和吸力面最大厚度点相对位置的变化带来的气动收益,形成了相对较优的叶型优化方案,实现了跨音转子工作裕度和等熵效率5.9%和0.32%的提升。

Three key geometric parameters of blade tip section of NASA Rotor37,the streamwise curvature distribution characteristics,the relative location of the maximum thickness point of the suction surface,and the radius of the trailing edge,were chosen and nine schemes were designed by orthogonal test method,to well analyze the influence degree of each geometric parameter on the overall performance of transonic rotor.The results show that the three geometric factors have less influence on the isentropic efficiency and total pressure ratio of rotor,while produce significant variation of stall margin.Meanwhile,the orders of the degree of influence of the three geometric factors on the stall margin are as follows:the streamwise curvature distribution characteristics of blade tip,the relative location of the maximum thickness point of the suction surface,and the radius of trailing edge.The streamwise curvature distribution characteristics may change the streamwise loading distribution of blade tip which affects the tip flow structure and stall margin of transonic rotor.Based on the analysis above,an optimal scheme was established,which produced increases of 5.9%in stall margin and 0.32%in isentropic efficiency respectively.