缝隙扩压叶栅近壁流场与流动损失实验

Experimental Investigation of Near-Wall Flow and Flow Loss in Compressor Cascades with Slots Injection

关键词:  压气机叶栅  缝隙叶片  附面层  流场  流动损失 

Key words:  Compressor cascades  Slot blade  Boundary layer  Flow field  Flow loss

摘要:

为了探索缝隙射流对高负荷扩压叶栅气动性能与近壁流场结构的影响机制,实验研究了设计冲角下有/无缝隙结构的高负荷弯曲扩压叶栅近壁流场结构与出口气动损失分布规律,获得了叶片近壁压力场数据、流动图谱以及叶栅出口流动损失参数。结果表明,缝隙两端压差导致的从叶片压力面到吸力面的射流能够增加附面层高熵流体的能量,缝隙射流将局部积聚的低能流体及时引向主流,减小高熵流体在叶展中部或端区掺混撞击,抑制了栅后尾迹高熵流体的过度聚集,从而有效提高高负荷压气机叶栅气动性能。 

Abstract:

In order to explore the influence mechanism to the aerodynamic performance and the near-wall flow structure on a high load compressor cascade with slots injection, the cascade near-wall flow structure and flow losses in outlet were investigated experimentally on the high-loading compound lean compressor cascades with/without slots under the design incidence angle. The cascade near-wall pressure, flow contour and the outlet flow loss parameters were obtained. The results indicate that the energy of the boundary layer high entropy fluid is increased via the air injection, which is implemented via the slot penetration through the pressure and suction surfaces under the effect of the pressure difference between the two sides.The local concentration low energy fluid is led to mainstream in time.The impact and mixing effect, the excessive accumulation of high entropy fluid are controlled preferably in wake region after cascade.Thus,the aerodynamic performance of high-loading compressor cascade is improved effectively. 