沟槽面对扩压叶栅表面流态的影响

采用油流显示技术研究了沟槽面扩压叶栅表面流动的拓扑结构,通过与光滑叶栅壁面流动拓扑图像的比较,发现沟槽面能抑制叶背附面层的发展,减小附面层内低速流体的展向流动,减弱叶背附面层与叶背角区旋涡的相互作用.随后用总压耙对栅后流场进行了测量,和光滑叶栅测量结果相比,沟槽面叶栅端壁区总压损失低,主流区沟槽面叶栅尾迹宽度变小、损失降低,证实该非光滑面能减小叶栅二次流损失.

EFFECTS OF A KIND OF GROOVE SURFACE ON THE SURFACE FLOW FIELD OF A COMPRESSOR CASCADE

The surface-flow topology structures of the compressor cascade with groove surfaces were studied using oil-visualization techniques.Compared with the flow topology structures in the smooth- surface cascade,the results indicated that the groove surface could restrain the development of the boundary layer and decrease the span-wise flow of the low-speed fluids on the suction surface,and could weaken the reaction between the boundary layer and the vortices at the corner.Measurement results at the cascade exit using total-pressure probes showed that the total-pressure loss in the groove-surface cascade was lower while the mid-span cascade wake narrowed,compared with the smooth-surface cascade.It confirmed that the groove-surface could reduce the secondary loss of the cascade.