Abstract Increasing the blade loading of a low pressure turbine blade decreases the number of blades, thus improving the aero-engine performance in terms of the weight and manufacture cost. Many studies focused on the blade-to-blade flow field of ultra-high lift low pressure turbines. The secondary flows of ultra-high lift low pressure turbines received much less attention. This paper investigates the secondary flows in an ultra-high lift low pressure turbine cascade T106C by large eddy simulation at a Reynolds number of 100,000. Both time-averaged and instantaneous flow fields of this ultra-high lift low pressure turbine are presented. To understand the effects of the inlet angle, five incidences of ‒10°, ‒5°, 0, +5° and +10° are investigated. The case at the design incidence is analyzed first. Detailed data is used to illustrate the how the fluids in boundary layers develops into secondary flows. Then, the cases with different inlet incidences are discussed. The aerodynamic performances are compared. The effect of blade loading on the vortex structures is investigated. The horseshoe vortex, passage vortex and the suction side corner vortex are very sensitive to the loading of the front part of the blade.

中文翻译：

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超高升程低压汽轮机级联中不同入口处二次流的大涡模拟

摘要 增加低压涡轮叶片的叶片载荷可以减少叶片数量，从而提高航空发动机在重量和制造成本方面的性能。许多研究集中在超高升力低压涡轮机的叶片到叶片流场。超高升力低压涡轮机的二次流受到的关注要少得多。本文通过雷诺数为 100,000 的大涡模拟研究了超高升程低压涡轮叶栅 T106C 中的二次流动。介绍了这种超高升力低压涡轮的时均流场和瞬时流场。为了了解入口角的影响，我们研究了 ‒10°、‒5°、0、+5° 和 +10° 的五种入射角。首先分析设计事故的情况。详细数据用于说明边界层中的流体如何发展为二次流。然后，讨论了具有不同入口发生率的情况。空气动力学性能进行了比较。研究了叶片载荷对涡流结构的影响。马蹄形涡、通道涡和吸力侧角涡对叶片前部的载荷非常敏感。