The application of passive jet vortex (PJV) on a high-speed compressor cascade for flow separation control was studied numerically. The effectiveness of the technique at off-design conditions was investigated. Results indicated that the PJV could reduce the total pressure loss coefficient by 5.2% at the designed angle of attack

and by 7.8% under different angles of attack

validating its high control efficiency and good adaptability. With the increase of the angle of attack

the flow separation on the blade suction surface would take place earlier and the distance between the jet exit and the separation region would decrease

which could strengthen the effect of PJV in enhancing momentum exchange and reorganizing the vortex structures like the passage vortex and the concentrated shed vortex within the passage

thus delaying the flow separation and reducing flow losses. Taking different angles of attack into consideration

it is suggested that the PJV be located near the upstream separation region. The optimum location of the jet is at 40% axial chord length from the blade leading edge.