有叶顶间隙的涡轮弯叶栅拓扑与旋涡结构(Ⅱ)——横截面流场拓扑结构与叶栅旋涡结构

Topology and Vortex Structures of a Curving Turbine Cascade With Tip Clearance (Ⅱ)-Topological Flow Pattern and Vortex Structure in the Transverse Section of a Blade Cascade

根据具有叶顶间隙的直叶栅和正、反弯叶栅壁面流动的墨迹显示以及横截面内气动参数测量 ,应用拓扑学原理 ,分析了叶栅流道横截面内的拓扑结构· 与直叶栅比较 ,叶片正弯消除了上通道涡分离线 ,并使二次涡由闭式分离转变为开式分离 ,而叶片反弯仅影响奇点位置、旋涡强度与尺度·

By means of ink trace visualization of the flows in conventional straight, positively curved and negatively curved cascades with tip clearance, and measurement of the aerodynamic parameters in transverse section, and by appling topology theory, the topological structures and vortex structure in the transverse section of a blade cascade were analyzed. Compared with conventional straight cascade, blade positive curving eliminates the separation line of the upper passage vortex, and leads the secondary vortex to change from close separation to open separation, while blade negative curving effects merely the positions of singular points and the intensities and scales of vortex.