亚声速轴流压气机叶顶喷气设计规律的试验研究

The study is to investigate the tip injection method in a subsonic axial flow compressor. The effects on compressor stability of injection mass flow, injector throat height, circumferential coverage percentage, injection position, injector numbers and injector distribution were experimentally studied. The flow mechanism of stability improvement and the effect on compressor stall dynamic were analyzed. The similarities and differences of tip injection method in the subsonic and in the transonic compressor were summarized. The results show that the stall dynamic of the compressor is not changed by tip injection, and the effective depression on tip blockage mainly accounts for the enhancement of compressor stability. The unsteady response of tip blockage to the tip injection is primary responsible for the effectiveness of discrete tip injection with a partial circumferential coverage. Stability margin is improved by 15% employing 0.66% of the annulus mass flow when the injectors are choked. The effects on compressor stability of the injection mass flow, injector throat height and circumferential coverage percentage interact with each other. The effects on compressor stability improvement of injection position, injector circumferential distribution and inlet distortion are limited. When the compressor stall is triggered by tip leakage vortex resulting in a spike stall, the design methodology of tip injection derived from a subsonic compressor can be adopted in a transonic compressor.