【摘要】 角区分离对叶轮机性能有重要影响。本文根据角区流动特征推导出描述角区三维附面层的等效二维附面层模型,并结合二维附面层分离准则,建立了角区分离判定准则。理论分析表明：为抑制角区分离,应尽量增大叶表吸力面与端壁相交二面角；为抑制角区分离,应使二面角α沿流向逐渐增大,或使二面角α沿流向逐渐减小过程尽量平缓,尤其在二面角α较小区域更应如此．鉴于此,建议风扇/压气机设计中应严格监控角区二面角大小及二面角流向变化梯度,以实现对角区分离的良好控制．结论也适用于其它叶轮机。更多还原

【Abstract】 Corner separation plays an important role in determining turbomachinery performance. This paper presents a model for describing the influences of SUC-EW dihedral angle on corner separa- tion in turbomachinery,in which SUC-EW dihedral angle refers to the dihedral angle at the intersection line between blade SUCtion and End-Wall surfaces.Based on the physical intuition of that the three- dimensional (3D) corner boundary layer is the conflux of both blade and end wall boundary layers, an equivalent two-dimensional(2D) corner boundary layer is put forward to predict the behavior of corner boundary layer.In this procedure,the cross flow effect in corner boundary layer and the three- dimensionality of the nearby main flow are ignored.The influence of the SUC-EW dihedral angle is included by another assumption.That is,the aero blockage and momentum loss of both blade and end wall boundary layers are conserved during the procedure of superimposing the two (both blade and end wall) 2D boundary layers to form the equivalent corner one.Then the corner separation is judged by combining the behaviors of the three boundary layers,i.e.the blade,the end wall and the equivalent 2D corner boundary layers.The present model reveals the influence of the SUC-EW dihe- dral angle and its streamwise gradient on the corner separation.Carefully monitoring and controlling this dihedral angle and its streamwise gradient are important ways to alleviate or even eliminate the corner separation.Simple numerical investigations show that the model is qualitatively correct.更多还原