Numerical simulation was carried out to explore the benefit of inducer tip endwall bleeding effects on centrifugal compressor stability enhancement. Based on the experimental results of the centrifugal compressor with a self-recirculating casing treatment on top of inducer

three tip bleeding configurations (A

B and C) with different bleed rates were simulated. The result shows that bleed position and bleed range have grate influence on stability enhancement effect. Configurations C is the best location because it has the largest bleeding area covers the whole tip backflow zone. Additionally

with the variation of suction flow rate

there are two different mechanisms of stability extension.When the flow rate is low

bleeding can suppress the tip leakage flow and remove low momentum fluid

so the channel blocking will be reduced to delay endwall stall. Otherwise

larger rate of suction flow will occupy the channel and the main flow will be pushed towards hub side to improve the rim power of the rotor. Considering the compression efficiency

lower bleeding rate has advantages. For configuration C

5% is the optimum bleed rate with the margin increase by 19.6%.