The unsteadiness such as boundary layer transition and turbulence at high angles of attack result in lift loss and increase in drag over an aerofoil. Numerous techniques such as suction at slots, flaps, bumps, high lift devices etc. have been developed by the scientists to control the separation delay and thereby prevent the aerodynamic losses at higher angles of attack. This research work aims at studying the effects of delaying the boundary layer separation by adopting blowing active flow control with local jets with varying velocity ratios and at different angles of attack on a 2D NACA 0084M aerofoil. Four different ratios of jet velocity (viz., 1, 2, 6 and 12) have been considered and the aerodynamic performance of each has been evaluated. The research aims to focus on the improvements in lift and drag characteristics of the above mentioned aerofoil and identify the best possible jet velocity.