Experimental Investigation of Stall Margin Enhancement of a Two-Stage Compressor With SPS Casing Treatment Under the Rotating Inlet Distortion

The experimental research about stall margin enhancement of a two-stage compressor with the SPS casing treatment is carried out in this paper. A rotating wire mesh at various speed co- and counterclockwise is used to simulate the rotating inlet distortion. And the main target is to investigate the effects of the rotating inlet distortion and to evaluate the SPS casing treatment's ability for stability strengthening when it is placed on the first stage of the compressor. The experiment results show that the SPS casing treatment can enhance the stall margin (2%~7.9%) of the compressor at various distorted conditions without additional efficiency loss. When the distortion speed is 600r/min, the rotating inlet distortion would lead adverse effect on the compressor, including the stall margin loss and sharp decline of the peak efficiency. But the distortion, in both two directions, turns to weak its infaust effect on the compressor stall onset when the distortion speed is higher than 800r/min. Compared with co-rotational distortion, the counter-rotational distortion is much better for the stability of the compressor.