A practical method to control the separation by cutting a slot through the pressure surface and the suction surface was proposed. A converged turning slot configuration was designed. The flow performance with different incidences was investigated. The experimental result was used to check the CFD result

so as to acquire the quantitative flow field structure. The structural static analysis was made. The results show that

in the incidence of 4 degree

the application of slot decreases the wake width of cascades by 16.7%

and decreases the peak of total pressure loss coefficient by 6.07%. In the incidence of 6 degree

the application of slot decreases the peak of total pressure loss coefficient by 14.7%. Fluid can flow from the pressure side to the suction side with slot configuration. The injection air increases the velocity of boundary layer

therefore enhancing its ability to resist the flow separation. Consequently it can decrease the total pressure loss

increase the static pressure ratio

and expand the stability range. It is thus necessary to reduce the stress concentration on fore wall of channel.