吸附式叶栅抽吸流与激波相干性研究

Investigation of the Interaction Between Suction Flow and Shock Wave in BLS Cascade

以某高负荷静子叶栅为研究对象,应用数值模拟方法分析了其在不同工况下附面层拓扑结构特点,针对该分离现象实施附面层抽吸,分析了激波与附面层相干过程,探讨了抽吸流与槽道激波的相干作用。结果表明(:1)在有激波、无抽吸条件下,附面层发展一般会经历分离泡产生、破碎、附着叶片表面的过程之后进入大分离状态(;2)吸力面开孔进行附面层抽吸,在一定程度上可以提高静压比,同时损失变化不大(;3)在激波后实施附面层抽吸,会使激波向下游漂移,其后附面层分离更为严重,因此在槽道存在激波时,若实施附面层抽吸,应该预先考虑抽吸气流与激波的相互干涉作用。

To explore a reasonable location of BLS （Boundary Layer Suction） for a high load cascade, the detailed flow structure of the cascade on-design and off-design working conditions have been investigated by numerical simulation. On base of the results, different BLS projects have been employed to explore an effective BLS way that could control separating flow and improve the pressure ratio while the loss could be kept little. The interaction between shock wave and suction flow, location of reasonable suction slot has been analyzed in detail. The results show that, （1） A separating bubble can be visible behind the shock wave when BLS was not employed. And this bubble broke up instantly and reattached the blade surface before the boundary layer turned into serious separation; （2） BLS could improve the pressure ratio to some extent and the loss could keep invariable when the suction slot and suction mass flow was reasonable; （3） The BLS behind shock wave could pump the shock wave to the downstream and improve the flow structure fractionally, however, the separation flow might happen near the new shock wave. The interaction between shock wave and suction flow should be considered preliminarily when the suction slot located behind the shock wave.