亚音轴流压气机近失速时叶尖流动的数值研究

以西北工业大学亚音轴流压气机实验台的孤立转子为研究对象,对其进行了单通道定常、非定常的全三维数值模拟,研究了轴流压气机近失速工况下转子叶尖流动特性。通过对比分析转子在最高效率工况和近失速工况下的定常模拟结果,发现在近失速工况下转子叶顶流线变得更加切向,来流攻角不断增大,最终导致失速的发生。非定常模拟指出,在失速先兆区转子叶顶出现了前缘溢流和尾缘回流的现象,这满足突尖型失速先兆出现的两个准则,所以压气机为突尖型失速。

Numerical Study on Flow of Blade Tip in a Subsonic Axial-flow Compressor Near Stall

In this paper,3-D steady,unsteady numerical simulation of the subsonic axial-flow isolated rotor was investigated to study the flow characteristic of blade tip in a axial-flow compressor at near stall condition.Analyzing contrastively the steady solution of the rotor at peak-efficiency and near stall condition,it′s found that streamline of the tip of rotor become more tangential,the attack angle of the approach flow increases continuously.At last,stall happens.Unsteady numerical simulation finds that the leading edge appears overflow and the trailing edge appears backflow at the blade tip at stall precursor,this meets two formulas that spike stall precursor appears,so spike stall happens for the compressor.