基于大弯角扩压静子叶栅的组合流动控制方法研究

为更好地控制叶中尾缘分离及角区分离，优化叶片吸力面流动分离结构，本文提出了全叶高槽道加全弦长端壁抽吸的组合流动控制方案。此外，本文还设置了全叶高开槽方案与端壁抽吸方案，以探究全叶高槽道射流与端壁附面层抽吸的相互作用机理。以一大弯角扩压静子叶栅为研究对象，本文对三种流动控制方案进行了详细的性能分析及对比。结果表明：组合控制方案对于原型叶栅叶中尾缘分离及角区分离的综合控制效果最佳，能够在全攻角范围内分别将原型叶栅的总压损失、气流转折角及静压升系数平均增大-38.4%、3.1°及16.2%。相比于全叶高开槽方案，组合控制方案的端壁抽吸槽有效抑制了全叶高槽道出口前端壁二次流的发展，进一步削弱了角区分离。相比于端壁抽吸方案，组合控制方案的全叶高槽道则有效消除了尾缘分离，避免了叶中流场的恶化。总体看来，组合控制方案有利于最大程度地拓宽叶片的可用攻角范围，提高其扩压能力。

Combined Flow Control Method Based on Large-Camber Compressor Stator Cascade

To better control the midspan trailing edge separation and corner separation, optimizing the flow separation structure on the suction surface of the blade, a combined flow control scheme with full-span slot and full-chord-length end-wall suction was proposed in this study. Moreover, the full-span slotted scheme and the end-wall suction scheme were set up in this study, to investigate the interaction mechanism between the full-span slot jet and the end-wall boundary layer suction. A large-camber compressor stator cascade was selected as the research object, and this study carried out detailed performance analysis and comparison of the three flow control schemes. The results showed that: The combined control scheme has the best comprehensive control effect on the trailing edge separation and corner separation in the original cascade. It can respectively increase the total pressure loss, turning angle and static pressure rise coefficient of the original cascade by -38.4%, 3.1° and 16.2% on average in the full incidence angle range. Compared with the full-span slotted scheme, the end-wall suction slot of the combined control scheme could effectively suppress the development of the end-wall secondary flow before the full-span slot outlet, further reducing the corner separation. Compared with the end-wall suction scheme, the full-span slot of the combined control scheme could effectively eliminate the trailing edge separation, avoiding the deterioration of the midspan flow field. Overall, the combined control scheme is conducive to widening the available incidence angle range of the blade and improving its diffusion capability.