Rotating Stall Inception Due to Breakdown of Tip Leakage Vortex in Compressor Rotors

压气机转子叶尖泄漏涡流破坏引起的旋转失速

基本信息

批准号：
12650172
负责人：
FURUKAWA Masato
金额：
$ 2.37万
依托单位：
Kyushu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12650172/
关键词：
Turbomachinery Compressor Rotor Blade Row Tip Leakage Vortex Vortex Breakdown Rotating Stall Stall Inception

项目摘要

The unsteady flow nature caused by the breakdown of the tip leakage vortex in an axial compressor rotor at near-stall conditions has been investigated by unsteady three-dimensional Navier-Stokes flow simulations and by experimental measurements. The simulations show that the spiral-type breakdown of the tip leakage vortex occurs inside the rotor passage at the near-stall conditions. Downstream of the breakdown onset, the tip leakage vortex twists and turns violently with time, thus interacting with the pressure surface of the adjacent blade. The motion of the vortex and its interaction with the pressure surface are cyclic. The vortex breakdown causes significant changes in the nature of the tip leakage vortex, which result in the anomalous phenomena in the time-averaged flow fields near the tip at the near-stall conditions: no rolling-up of the leakage vortex downstream of the rotor, disappearance of the casing wall pressure trough corresponding to the leakage vortex, large spread of t … More he low-energy fluid accumulating on the pressure side, and large pressure fluctuation on the pressure side. As the flow rate is decreased, the movement of the tip leakage vortex due to its breakdown becomes so large that the leakage vortex interacts with the suction surface as well as the pressure one. The interaction with the suction surface gives rise to the three-dimensional separation of the suction surface boundary layer.Unsteady full passage flow fields at a near-stall operating condition in the axial compressor rotor has been investigated by RANS simulation. The simulation has captured the nature of the rotating stall inception. It is found that the stall cell is part-span type and consists of a tornado-type separation vortex linking from blade suction surface near the tip to the casing. The spiral-type breakdown of the tip leakage vortex causes the interaction between the leakage vortex and the adjacent blade leading edge, thus resulting in the formation of the tornado-type vortex. Less

通过非定常三维纳维-斯托克斯流模拟和实验测量，研究了近失速条件下轴流式压气机转子中叶尖泄漏涡破裂引起的非定常流动性质。模拟表明，螺旋型破裂。在接近失速条件下，叶尖泄漏涡流发生在转子通道内部，叶尖泄漏涡流随着时间的推移剧烈扭曲，从而与压力表面相互作用。涡流的运动及其与压力面的相互作用是周期性的，涡流破裂导致叶尖泄漏涡流的性质发生显着变化，从而导致叶尖泄漏涡流附近的时间平均流场出现异常现象。近失速工况尖端：转子下游泄漏涡没有卷起，泄漏涡对应的机壳壁压力槽消失，泄漏涡流扩散大。低能流体在压力侧积聚，压力侧压力脉动较大。随着流量的减小，叶尖泄漏涡由于其击穿而产生的运动变大，导致泄漏涡与吸力面相互作用。与吸力表面的相互作用引起吸力表面边界层的三维分离。采用 RANS 研究了轴流式压缩机转子近失速工况下的非稳态全通道流场。模拟捕捉到了旋转失速的本质，发现失速单元是部分翼展型的，并且由从靠近叶尖的吸力表面连接到机壳的龙卷风型分离涡流组成。叶尖泄漏涡的破坏导致泄漏涡与相邻叶片前缘之间的相互作用，从而导致龙卷风型涡的形成。