叶身/端壁融合技术研究

角区流动的现象普遍存在,其中角区流动分离是制约叶轮机性能提升的关键因素。针对抑制或消除角区分离情况,在简要回顾二面角原理的基础上,提出叶身/端壁融合技术(Blended Blade-EndWall,BBEW),指出了其所包含的二面角原理的3种应用方式,并以NASA 67号转子叶片为例,采用数值方法研究了应用第2种方式(即增大过渡曲面最小曲率半径方式)的改型效果。结果表明:采用二面角原理第2种应用方式的BBEW能够有效地减弱或消除高负荷叶片吸力面角区分离,进而明显改善了67号转子叶片性能,因此BBEW是抑制或消除角区分离的有效技术。

Investigation on Blended Blade and Endwall Technique

Corner flow was a common phenomenon, and corner flow separation was the key factor to further improve the performance of turbomachinery. In order to suppress or eliminate the corner flow separation, Blended Blade and EndWall(BBEW) technique was proposed on basis of the principle of dihedral, which included the three ways of application. Taking NASA rotor balde 67 as an example, the improvement effect of the second way was investigated by numerical methods, which increased the minimum curvature radius of curved transition surface. The results show that the corner separation of the high load blale suction side can be efficiently suppressed and eliminated by the BBEW, and the performance of the rotor balde was improved obviously. Therefore, the BBEW technique is effective to suppress or eliminate the corner separation.