组合压气机中导流叶片的尾迹抖动特性

Stator wake variability in a combined compressor

为明确多排叶栅压气机中影响静叶尾迹抖动特性的因素及机理,探索调制静叶尾迹抖动周期和幅值的方法,采用数值方法对设计流量为1.12kg/s,转速为60 000r/min的一级轴流和离心叶轮组成的组合压气机的非定常流场进行模拟.结果表明:静叶尾迹抖动除受几何因素影响外,还受上下游转子干涉影响,且上下游转子叶片通过频率的异同将影响静叶尾迹抖动的周期性.当上下游转子叶片同频通过时,改变动叶的时序位置可以调制静叶尾迹抖动幅值的大小.另外,静叶尾迹抖动幅值沿叶高方向并不相同,低叶高处静叶尾迹抖动幅值明显大于中、高叶高处静叶尾迹抖动幅值.

The unsteady flow in a combined compressor, which consists of axial flow and centrifugal compressor impellers, was simulated numerically at mass flow of 1.15 kg/s and speed of 60kr/min （design point）. The objective was an in-depth analysis of the factors caused stator wake variability. In addition, a method about changing cycle and amplitude of stator wake variability was presented. The results indicate that= stator wake variability is influenced by geometric factor, up and downstream moving rows. The blade passaging frequencies of up- and downstream rotor are related with the cycle of stator wake variability. Note that the equal blade passaging frequencies in all stages, the clocking positions have much effect on the amplitudes of stator wake variability. Moreover, along the blade＇s highness, the amplitudes of stator wake variability are different, which located at low span was greater than that at mid-span and high-span.