叶轮机转子叶排非定常旋涡脱落频谱特性研究新方法

在研究叶轮机械转动部件非定常旋涡脱落频谱特性时,难以避免会遇到旋转坐标系向绝对坐标系转换的问题.笔者通过理论推导,得出了坐标转换情况下各个旋转模态的变化规律,总结出两大判读频谱特性的判据.据此判据对动态实验测量结果进行了分析,准确地捕捉到了转子叶排非定常旋涡脱落的典型特征频率.而对后期的PIV流动显形实验结果进行分析时,又进一步验证了理论推导以及实验测量所得结论的正确性.笔者提出的实验分析方法可有效地确定非定常旋涡脱落的特征频率,为实现非定常流动控制以及轴流压气机非定常耦合流型提供重要的依据.

A new method for studying the unsteady vortex frequency characteristics on rotor blades of turbine engine

The problem of altering the rotating coordinate system to absolute coordinate system is often encountered when the frequency characteristics of unsteady vortex shedding in turbine engine is studied.In this paper,the regulation of each rotating mold at this coordinate conversation is found out by theory deducing,and two criteria for identifying the frequency characteristics are concluded.According to the two criteria the results of dynamic measurement are analyzed,and the typical frequency of unsteady vortex shedding at rotor blades is catched accurately.The results in the next experiment investigation of PIV verify the conclusions of theory deducing and the experiment measurement exactly.This new experimental analysis method can find out the typical frequency of unsteady vortex shedding,and offer a most important confirmation for the unsteady flow control and new unsteady cooperative flow type in axial-flow compressor.