A new approach of endwall recirculation in axial compressors

摘要

This study reports on a novel design of endwall recirculation in a transonic axial flow compressor rotor. The bled air from downstream of the rotor is injected over the tip clearance of the blades in the circumferential direction opposite to the blade rotation. Results reveal that the treated casing effectively increases the operating range of the rotor at the expense of some efficiency loss. It is shown that the endwall recirculation applied in this work does not reduce the incidence angle upstream of the blade but reduces the pressure difference between the pressure and suction surface and pushes the leakage vortex and the passage shock downstream. The endwall flow was found to be responsible for stall initiation in the treated casing (similar to the smooth casing). (C) 2020 Elsevier Masson SAS. All rights reserved.