Effect of Different Radial Inclined Angles of Self-circulation Casing Treatment on the Transonic Axial Flow Compressor Performance

Unsteady numerical simulation of single passage was carried out on NASA Rotor 35 to study the influence radial inclined angle self-circulation casing treatment (SCT) performance and stability a transonic compressor at 100% design speed. The angles were set 0°(D0), °(D30) 60°(D60), respectively. calculated result indicates an increase in stall margin improvement (SMI) efficiency (DEI) as increases gradually. SMI SCT with 60° is 12.5%, biggest among three SCTs, peak improvements (PEI) SCTs are almost same. provided effect strengthening effect, which further improves stable working range compressor, loss also lower than that 0° structure. flow conditions inside bleeding part can be improved by radially skewing self-circulating structure toward rotor rotating direction.