摘要
采用三维黏性非定常数值模拟方法研究了某型高压涡轮端区非定常流动相互作用,着重研究了上游静子尾迹与转子二次流的非定常作用机制,同时还分析了负荷分布、激波等对端区非定常流动的影响。结果表明,静子尾迹的非定常作用一定程度减小了转子轮毂二次流的径向涡量;尾迹对流向涡量的影响取决于尾迹沿叶高的分布,当吸力面一侧的尾迹具有与二次流方向相反的流向涡量时,二次流的流向涡量减小;非定常效应还使得转子叶片根部负荷略为减小,也一定程度上抑制了转子轮毂二次流的发展。此外,受静子尾缘激波的影响,转子叶片表面负荷分布发生明显的周期性变化,导致叶片表面承受较强的非定常力,在涡轮设计中必须考虑。另外,通过计算涡轮级中的熵增和熵产,定量地分析了端区非定常相互作用产生的损失,并得到了一些有意义的结论。
An investigation into the unsteady flow interaction at the endwall region of a high-pressure turbine stage is performed by numerical simulation with a 3D unsteady viscous solver. The article examines the un- steady interaction between stator wakes and rotor passage vortices. The effects of blade loading and shockwav- es are also revealed. The results indicate that periodic stator wakes can reduce the radial vorticity of hub pas- sage vortex. The unsteady effects of stator wakes on the streamwise vorticity of hub passage vortex depend on wake distribution. The vorticity decreases if the wakes from the stator suction side have the direction opposite to the streamwise vorticity with hub passage vortex. And the unsteady effects of stator appreciably reduce the rotor blade load near the endwall, which can suppress hub passage vortex development. On the other hand, the trailing edge shock systems of the stator and rotor cause a significant periodic change in the rotor surface pressure field, which is a factor to be considered in design. In addition, by evaluating the entropy increase and entropy generation in the turbine stage, the unsteady losses are investigated quantitatively, which leads to some significant conclusions.
出处
《航空学报》
EI
CAS
CSCD
北大核心
2009年第4期584-596,共13页
Acta Aeronautica et Astronautica Sinica
基金
国家自然科学基金(50776003)
北京航空航天大学“蓝天科研新星”计划
关键词
二次涡
上游尾迹
激波
非定常相互作用
涡轮
passage vortex
upstream wake
shock wave
unsteady interaction
turbine
