Effects of slot jet and its improved approach in a high-load compressor cascade

Experimental investigations are conducted in this paper to study a slot jet approach. Measurements inside a high-load compressor cascade were performed to evaluate its gains and reveal its mechanisms. Further, an improved approach is developed on the basis of the individual slot jet approach. Experiments shows that the individual slot jet is highly efficient at reducing trailing-edge separation by directly speeding up separated fluids, but it is not so efficient at reducing the corner stall. To further reduce the corner stall, the improved approach introduces a vortex generator into the flow field. The individual slot jet partly reduces corner stall by restricting the passage vortex and concentrating the separation at the cascade corner, which happens to offer convenient conditions for the vortex generator to further reduce flow loss. The vortex generator, which produces a counter-rotating vortex to counteract the passage vortex, prevents the formation of the end-wall cross flow. Therefore, both the trailing-edge separation and corner stall are significantly suppressed, so that the improved approach achieves more powerful flow control effects.