可控扩散叶型与双圆弧叶型实验对比研究

Experimental Comparison of Controlled Diffusion Airfoils with Double Circle Airfoils

关键词:  可控扩散叶型  双圆弧叶型  平面叶栅  气流分离  压气机

Key words:  Controlled diffusion airfoil  Double circle airfoil  Cascade  Flow separation  Compressor

摘要:

为对比不同压气机叶型的流动特征，在高亚声速平面叶栅风洞内对相同设计速度三角形的可控扩散叶型和双圆弧叶型进行了平面叶栅实验，对两套叶型的表面马赫数、尾迹总压等参数分布进行了测量。实验结果表明:设计点可控扩散叶型总压损失比双圆弧叶型小近1倍，出口气流角小2.0°；在吸力面气流分离前，出口气流角随攻角和马赫数变化小于1.0°，尾迹核心区位置保持不变；双圆弧叶型吸力面近尾缘存在一定区域气流分离，受分离区影响，随进口马赫数增加，出口气流角变化达到4°，尾迹核心区移动了近20%栅距。

Abstract:

In order to compare the flow characteristics of different compressor airfoils，experiments has been made on a controlled diffusion airfoil (CDA)，as well as a double circle airfoil (DCA) in a high subsonic cascade wind tunnel. The two airfoils are designed for the same velocity triangle at subsonic condition，and the experiments contain the measurement of surface Mach number and the wakes profiles. The results show that the total pressure loss of the controlled diffusion airfoil is nearly half of the double circle airfoil，so is the exit flow angle 2° smaller than that of the double circle airfoil. Before the flow separates on the suction side of CDA，the variations of exit flow angles are within 1° with the incidence and inlet Mach number varying. The core region of the wakes keep fixed among the pitch. However，there is a small flow separation region near the trailing edge of the double circle airfoil，which results in the flow loss and the deficit of flow turning. With the inlet Mach number increasing，the variations of the exit flow angles amount up to 4°，and the core region of the wakes move nearly 20% pitch.