边界层吸入跨声速复合掠型风扇气动性能研究

Aerodynamic Performance Study for Transonic Compound Swept Fan with Boundary Layer Ingestion

关键词:  边界层  复合掠型  跨声速风扇  分布式推进  总压畸变  气动性能

Key words:  Boundary layer  Compound sweep  Transonic fan  Distributed propulsion  Total pressure distortion  Aerodynamic performance

摘要:

针对边界层吸入条件下的跨声速风扇设计问题，提出了一种掠型叶片的设计方法，分析了三种前缘掠角分布对风扇气动性能的影响，并在边界层吸入情况下对比了复合掠型风扇和原型风扇的气动性能和流动特征，探讨了叶片通过低压畸变区过程中的流场变化。研究结果表明，均匀来流时复合掠型风扇没有改变原型风扇堵塞流量，但稳定裕度提高了7.1%；边界层吸入20%进口高度时，复合掠型风扇峰值效率比均匀来流时降低了1.8%。与Rotor 67风扇相比，复合掠型风扇能够在更低的流量工况下承受同等的来流参数畸变流场。在叶片通过畸变区域过程中，退出畸变流场时更容易触发旋转失速。

Abstract:

Focusing on the transonic fan design problem with the boundary layer ingesting， a swept blade design method is put forward and the effects of three leading edge swept angle distributions are investigated on fans’ aerodynamic performance. Furthermore， the flow field features and aerodynamic performance comparative analysis are also implemented between the original fan and the compound swept fan with the boundary layer ingesting. The flow field changes are also discussed when the tip blades pass by the low pressure distortion region. The results reveal that the compound swept fan does not change the original fan choke mass flow with the uniform inlet flow， and the stability margin has been improved by 7.1%.With the boundary layer ingesting up to 20% inlet height， the maximum efficiency of the compound swept fan has been reduced by 1.8% ，compared with the uniform inlet flow. Meanwhile， the fan can suffer the inlet distortion flow field at the same level with a lower mass flow than the Rotor 67 fan. When the tip blades pass by the distortion region， the rotating stall is more likely to be triggered at the time of dropping out of the distortion region.