轴流压气机旋转失速与喘振的实验研究

本文运用热膜和动态三孔针对孤立转子和多级压气机的旋转失速和喘振现象作了详尽的试验研究。基于频谱中多种频率并存的事实,提出翼型分离导致两类自激振荡的论点。根据多级压气机的试验结果,对其稳定工作边界的性态作了分析和讨论。 

ROTATING STALL AND SURGE IN AXIAL FLOW COMPRESSOR

Supported by the funds of the national natural science,we have tested and meassured the instability behavior of compressors in detail with hot-wire,hot-film probes and transient pressure 3-hole probes on single rotor,single stage and multi-stage compressors respectively.After analyzing signals with the power spectra and correlation analysis,it is found that there are two kinds of disturbances—peripheric oscillation and axial oscillation in the flow.On the basis of this fact,we propose the concept that the flow separation from airfoils results in peripheric oscillation and axial oscillation simultaneously,and provide a new model to describe the flow destabilizing mechanism. For the stability problem of multistage axial flow compressors,it is of practical value to investigate its stability limits,inclusive of the rotating stall margin.The preliminary results of this investigation show that the stability limit in the high speed regionis equivalent to a surge line,that the stability limit the middle speed region is indeed a stall line,and that the stability limit in the low speed region has two branches,one is the stall line of the whole compressor,the other is the rotating stall inception margin of the first stage.Both are of the same importance from the viewpoint of engine safety.Finally the mathematical methods for predicting the stability limits are discussed.