为了研究组合抽吸对高负荷压气机叶栅内部分离流动控制的效果和机理,以内部同时存在有吸力面附面层分离和角区分离的压气机叶栅为研究对象,利用实验和数值模拟对3种不同的抽吸方案进行了探索。结果表明:附面层抽吸可以显著地改善叶栅性能和攻角特性;在-5°~8°攻角范围内,吸附式叶栅的叶型损失系数得到了显著的降低,且抽吸量为0.76%时对应的损失系数降幅达到约67%;吸力面局部叶展抽吸方案(SS1)可以有效地消除抽吸叶展附近的分离,结果却导致角区分离面积变大;组合抽吸方案(CS)基本全部消除了叶栅内吸力面上的附面层分离和角区分离,因此全叶展上的负荷和扩压能力得到了显著的提升;不同攻角下损失系数随抽吸流量组合的变化规律不同,大攻角下吸力面上的抽吸控制更能有效地降低叶栅内的损失;进行组合抽吸时,需要针对不同的攻角选择最佳的抽吸流量组合。
In order to study the effectiveness and mechanism in controlling the flow separation for the highly loaded compressor cascade with combined boundary layer suction(BLS),a linear compressor cascade which has separated flows both on the suction surface and in the corner was investigated with experiment and numerical simulation,and three different suction schemes were explored. The results show that BLS can remarkably improve the performance and incidence characteristics of the cascade. The profile loss coefficient of the aspirated cascade is reduced significantly at the incidences from- 5° to 8°,and the loss coefficient can be reduced by about 67% at the suction rate of 0.76%. Part blade span suction scheme(SS1) can effectively remove the separation over the suction span resulting in the increase of separation area in the corner. The separated flows both on the suction surface and in the corner are almost completely eliminated by combined suction scheme(CS),therefore,the load and the diffusion capacity over the full span are improved significantly. The change law of the loss coefficient is different with variation of the suction rate combination at different incidences,and it is more effective to reduce the loss of cascade with suction control on suction surface at a high incidence. It is needed to choose the best combination of suction rate according to the incidence when conducting a combined suction.