跨声速压气机转子叶尖间隙流动失稳试验研究

Experimental investigation of rotor tip clearance flow instability in transonic axial flow compressor

以跨声速单级轴流压气机为试验对象,通过在机匣表面安装高频响应动态压力传感器测量转子叶尖间隙流场,观察了不同转速下转子叶尖间隙泄漏流动结构随工作状态变化的响应特征。试验结果表明:100%转速时,叶尖间隙泄漏涡通过脱体激波后会突然膨胀而出现涡破裂现象,在转子通道内形成大面积的高静压低速堵塞区,对转子叶尖区域通道造成严重堵塞,迫使叶尖间隙泄漏流在相邻转子叶片叶尖前缘发生溢流,最终触发压气机内部流动失稳。80%转速时,叶尖间隙泄漏涡对叶片通道主流区堵塞影响较小,通道激波对进口来流产生阻滞作用,气流在进入转子叶片通道进口前严重分离,使得整个转子叶片通道完全被堵塞,最终触发压气机内部流动失稳。

The tip clearance flow field of a transonic single stage axial flow compressor was measured by dy-namic pressure sensors installed at rotor casing surface. The changing response characteristics of tip clear-ance leakage flow structure with operating condition at different speeds were observed in detail. The experi-mental results show that the tip clearance leakage vortex expanses suddenly and break down after passingthrough the detached shock, and there is a large high static pressure blocking area existing in the rotor pas-sage at 100% design speed. Thus the flow passage of rotor tip area is blocked deeply, forcing the leakageflow spill at the leading edge of adjacent rotor balde, leading to flow instability of the compressor. At 80% design speed, the tip clearance leakage vortex has little blocking effect on the flow passage, and the shockwave blocks the coming flow. The boundary layer is seriously separated in front of the rotor passage inlet,and the entire rotor passage is blocked absolutely leading to flow instability of the compressor.