CFD Analysis of Co Flow Jet Airfoil

Abstract

The performance of airfoils can be improved by using flow control techniques like Co Flow Jet (CFJ) technique. Many of the control flow techniques are applied only near leading or trailing edge, whereas the CFJ technique is applied on most of the suction surface. In this technique an injection slot is made near the leading edge through which a jet is introduced. In order to maintain the conservation of mass principle, same amount of mass is sucked through a suction slot. In this paper the performance of NACA6409 baseline airfoil is compared with three CFJ airfoils with varying positions of injection and suction slots. The performance characteristics considered are coefficient of lift, stall margin and lift to drag ratio. The analysis is done using commercial code ANSYS FLUENT. It was found that the CFJ airfoils improve the stall margin by 33% to 67% compared to the baseline airfoil. The airfoil CFJ1 has optimum position of injection and suction slots. For this airfoil the lift coefficient increased by 47% and there was no considerable change in lift to drag ratio.