Theoretical analysis of rotating stall under static inflow distortion including the effect of tip injection

The present paper demonstrates the effect of static inflow distortion on axial compressor performance. Effect of tip injection on compressor performance under clean and distorted inflow condition is also investigated. The existing Moore- Greitzer model was extended to include the effects of static inflow distortion and tip injection. Theoretical results showed that the compressor performance deteriorated under the influence of static inflow distortion. It resulted in 25% reduction in pressure rise coefficient and about 3% deterioration in stall margin over the baseline case. I lowever, with tip injection, there was significant improvement in compressor performance. The study was further extended to demonstrate the effectiveness of tip injection under clean flow by varying the jet injection velocity ratio (VR). At VR=3, the surge onset was completely suppressed as against what was observed under same input parameters but with VR=1 and VR=2. At the peak compressor characteristic. VR=3 resulted in best performance under clean flow resulting in 5% improvement in stall margin and 1.5% increase in pressure rise coefficient.