1118 Effect of Tip Clearance on Rotating Stall Inception in an Axial Flow Compressor Rotor

The effects of the tip clearance on the rotating stall inception in an axial flow compressor rotor have been investigated by an EFD/CFD hybrid analysis. It has been found that the tip clearance plays an important role in the rotating stall inception. In the compressor with small tip clearance, the concentration of low energy fluid on the blade suction surface and the leading edge separation at the blade tip crucially influence the rotating stall inception. On the other hand, in the one with large tip clearance, tip leakage vortices are dominant in the flow field and their breakdown causes the rotating instability.