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低压涡轮湍流问题是制约高性能航空发动机研制的难点之一。为了理清低压涡轮内部湍流流动机理,并掌握相应的控制策略,获得计及非定常流动特征的高负荷低压涡轮气动设计方法,基于课题组长期从事高负荷低压涡轮的研究基础之上,结合国内外低压涡轮大量研究工作,系统地介绍了尾迹扫掠下低压涡轮叶片吸力面附面层发展演化过程、端区二次流非定常特征变化以及相应的流动损失机制及其抑制方法。优化叶片载荷分布在一定程度上能够减小叶型损失和二次流损失;尾迹扫掠能够诱导吸力面附面层发生转捩从而减小叶型损失,同时也有助于抑制端区二次流的发展,但在不同雷诺数下,尾迹的作用效果可能不同;对于高/超高负荷低压涡轮,特别是在低雷诺数条件下,需要借助有效的流动控制手段来抑制分离。
Low-pressure turbo turbulence is one of the difficulties that restrict the development of high-performance aero-engine. In order to sort out the turbulent flow mechanism in low-pressure turbine and to master the corresponding control strategy, the aerodynamic design method of high-load and low-pressure turbine considering unsteady flow characteristics is obtained. Based on the research of long-term high pressure and low pressure turbine, A great deal of work has been done on the low-pressure turbine. The development and evolution of the suction surface of the low-pressure turbine blade under wake swept, the unsteady characteristics of the secondary flow in the end zone, the corresponding flow loss mechanism and its suppression method are systematically introduced. Optimizing the blade load distribution can reduce the leaf loss and secondary flow loss to a certain extent. The wake sweep can induce the transition of the suction surface to reduce the leaf loss, and also help to restrain the secondary flow in the end zone However, under different Reynolds numbers, the wake effect may be different. For high / ultra-high pressure low pressure turbines, especially at low Reynolds numbers, effective flow control is required to suppress the separation.