叶轮机械叶片弯掠气动技术研究进展

Research Progress of Skew and Sweep Aerodynamic Technology for Turbomachinery Blades

关键词:  叶轮机械  叶片  弯曲  扫掠  叶型积叠

Key words:  Turbomachinery  Blade  Skew  Sweep  Stacking of blade profile

摘要:

叶片弯掠技术在叶轮机械设计中的应用，使叶片通道流场的稳定性得到了明显改善，叶轮机械的工作效率得到了显著提升。结合近年来在叶片弯掠气动技术领域开展的研究，详细综述了国内外叶片弯掠技术在叶轮机械设计中的研究进展。首先，回顾了叶片弯掠气动技术的发展历程，将叶轮机械叶片的设计分为3个阶段，分别是直叶片、扭叶片和以弯扭掠为主要特征的空间叶片，并指出以弯扭掠为主要特征的第3代叶片虽然已经得到应用，但仍有很多问题还没有完全解决。然后，分析现有研究中对叶片弯掠的定义，指出其本质均是在直叶片的基础上，通过移动叶型积叠点的位置使叶片产生弯曲或扫掠的效果，进而拓展叶片的设计空间。其次，综述了叶片弯掠对流场的影响，并归纳总结其作用机理是通过改变叶片对气流的作用力在径向的分量，实现叶片载荷和流量沿叶展的再分配，进而控制低能流体微团的输运，减小二次流损失。最后，对叶片弯掠气动技术在今后的发展方向进行了展望。

Abstract:

With the application of blade skew and sweep design technology in turbomachinery design， the stability of flow field in blade passage has been obviously improved， and the working efficiency of turbomachinery has been significantly improved. Based on the recent researches， the research progress of blade skew and sweep aerodynamic technology for turbomachinery design is reviewed in detail. Firstly， the development of blade skew and sweep aerodynamic technology is reviewed. The blade design of turbomachinery is divided into three stages， namely， straight blade， twisting blade and space blade characterized by skewing， twisting and sweeping. Although the 3rd generation blade characterized by skewing， twisting and sweeping has been applied， many problems have not yet been completely solved. Secondly， the definition of blade skew and sweep in the existing research is analyzed. The essence is that， on the basis of straight blade， the blade will be skewed or swept by moving the position of stacking point of blade profile， which expands the blade design space. Thirdly， the effect of blade skew and sweep on the flow field is summarized. The mechanism is to redistribute the load and flow along the blade span by changing the radial component of the blade force on the air flow， so as to control the transport of low-energy fluid clusters and reduce the loss of secondary flow. And lastly， the development trend of blade skew and sweep aerodynamic technology in the future is prospected.