The effect of adding multiple triangular vortex generators on the leading edge of a wing

The goal of this research was to investigate preliminary test data obtained by Professor Robert E. Bond at the University of Tennessee in the year 2001. Dr. Bond added triangular horizontal flat plates (vortex generators) to the leading edge of a wing, to delay flow separation at high angles of attack. The present approach was both experimental and computational. The experimental method was used to determine, with the aid of smoke, the angle of attack at which the wing stalled. For this qualitative method a wing (airfoil NACA 0015) was used. It had a 32 inch span and attached to its leading edge were eight equilateral triangular flat plates measuring three inches on each side. The computational method involved the use of the CFD Fluent software. The results obtained with the experimental method showed that, when the vortex generators had a 1 inch space in between each other, the flow remained attached to 16 degrees, but stalled at 18 degrees. Using different spacings, an increase in stall angle from two to five degrees was observed, as compared to a wing without vortex generators. Increasing the distance between the vortex generators affected the stall angle. The computational method gave trends that were similar to the experimental results. Each wing leading edge mounted triangular vortex generator produced a pair of counter rotating trailing vortices trailing in the direction of Vinfinity. When these vortices passed over the wing upper surface, they energized the boundary layer, thereby delaying the wing stall