一种测量跨声速多级压气机转子出口二维流场的方法

A Method of Measuring 2D Flow-Field at Rotor Exits of Transonic Multistage Compressor

关键词:  小型轴流压气机  级间测量  高频压力探针  误差分析  转子出口流场 

Key words:  Small axial-compressor  Inter-stage measurement  Fast-response pressure probe  Error analysis  Rotor-exit flow-field

摘要:

为了获得小型压气机设计所急需的关键流场信息,发展了一种基于圆柱单孔高频压力探针测量小型轴流压气机级间动态流场的测量方法。该探针测量原理基于圆柱绕流特性,借助高速锁相采集技术,利用旋转探针多角度法实现级间动态流场测量。采用插值和拟合对测量的数据进行处理,从而获得级间二维定常流场。误差分析表明,该探针测量精度较高,偏转角误差小于1.8°,马赫数、总压和静压的极限误差分别为3.4%,0.94%和3%。将该高频探针应用于某小型跨声速3级轴流压气机,测量结果表明:85%叶高至机匣范围内,总压和马赫数明显要比叶根低得多,气流出现明显过转。这些测量结果为优化该压气机级间匹配指明了方向,验证了该高频压力探针测试技术的工程应用价值。 

Abstract:

In order to obtain the key flow-parameters which are urgently demanded in small axial-compressor design, a method of measuring inter-stage unsteady flow-field in a small axial-compressor with a single-hole fast-response cylindrical-probe has been developed. The measuring method was based on the characteristics of flow around cylinder. Utilizing phase-locked technique, the inter-stage flow-field measurement was realized by rotating the probe at several angular positions. The interpolation and fitting method were used to process the test data. In this way, the inter-stage 2D steady flow-field was obtained. The error analysis shows that this probe possesses adequate measuring precision,in which the error of the yaw angle is less than 1.8° and the uncertainty of Mach number, total pressure and static pressure is, respectively, 3.4%, 0.94% and 3%. Then, the unsteady measurement technique of fast-response pressure probe was applied to an experimental investigation in a small three-stage transonic axial-compressor. The measurement results indicate that the total pressure and Mach number are obviously lower within 85%~100% span than those at lower half span, which leads to flow overturning. These results provide the key flow distribution for the optimization of inter-stage matching. Therefore, it verifies the engineering application of this fast-response pressure probe measuring technique. 