In order to further reveal the influence mechanism of blade tip winglet on the aerodynamic performance of transonic compressor rotor
a numerical study of aerodynamic performance of transonic compressor rotor with different blade tip winglets was carried out. Base on the analysis of transonic compressor rotor flow instability at different speeds
the mechanism of stability enhancement by blade tip winglet was discussed. It is found that the stall margin of the transonic compressor rotor with the widest pressure-side winglet can be increased by 8.1%
17.4% and 7.1% at 100%
80% and 60% design speed conditions respectively. At 100% and 80% design speed conditions
the shock/tip leakage vortex interaction and the blockage zone caused by the tip leakage vortex breakdown are the key factors inducing the flow instability in a transonic compressor rotor. The mechanism of stability enhancement by pressure-side winglet contributes to the reduction of blockage zone caused by the tip leakage vortex breakdown
due to the strength reduction of tip leakage flow and shock/tip leakage vortex interaction. At 60% design speed condition
the large area boundary separation on the rotor blade suction surface plays an essential role to the flow instability inception. Compared with the rotor without tip winglet
the equivalent incidence of the rotor with pressure-side winglet is reduced and the degree of three-dimensional separation on the suction surface is weakened.