Experiment investigation and mechanism analysis of interaction of variable inlet guide vanes and axial skewed slots casing treatment

The variable inlet guide vanes and axial skewed slots casing treatment are effective measures that can extend the operating range of compressor. In order to analyze the mechanism of the interaction of these two measures, the different guide vanes angle with original smooth wall as well as slots configuration were tested on a single-rotor compressor. At the same time, the guide vane angle of 10° with each casing configuration and the guide vane angle of 0° with original smooth wall configuration are simulated. The results of experiment and calculation show that the introduction of these two kinds of measures can gain greater improvement of the stall margin. The difference of the flow fields of the rotor was analyzed. The positive angle of the inlet guide vane can weaken the separation of suction part flow, but it does not change the phenomenon of the stall induced at tip of the rotor blade. The axial skewed slots can weaken the structure of tip leakage vortex to get the improvement of the stall margin. The different mechanism of these two measures can make sure that using these two measures at the same time can gain greater improvement of the stall margin.