后加载技术在极小展弦比叶栅中的应用

The Use of Rear-loading Technology in Ultra Low-aspect Ratio Cascades

具有后部加载载荷分布的透平叶片能有效控制叶片通道内二次流的形成 ,降低二次流动损失 ,同时该类型叶栅具有良好的攻角适应性 ,因此可以显著提高叶栅通道内的流动效率。本文应用后加载技术设计了一种具有后部加载特性的极小展弦比静叶栅。其叶栅的数值分析结果和实验结果表明 ,叶栅有低的三维叶栅损失 ,叶栅性能随不同展弦比、不同攻角和不同出口马赫数的变化不大。

Through the use of turbine blades with a rear-loaded load profile one can effectively control the formation of secondary flows in the blade passage, reducing secondary-flow losses. Meanwhile, this type of cascades is highly adaptive to a variety of incidence angles, thus significantly enhancing the flow efficiency in a cascade passage. An ultra low-aspect stator cascade with rear-loaded characteristics was designed by using the rear loading technology. The results of numerical analysis and test of the above-mentioned cascade indicate that the latter features a low three-dimensional cascade loss. Moreover, the cascade performance hardly changes with the change of aspect ratios, incidence angles and outlet Mach numbers.