Effects of Fence on the Spanwise Aerodynamic Characteristics of an Aircraft Wing Profile with Various Taper Ratios.

This paper investigates the effects of the chordwise fence on the spanwise change in aerodynamic characteristics of an aircraft wing with a different taper ratio for varying angles of attack. The investigation was carried out for the tapered wing with different taper ratios of 0.41, 0.6, and 0.75. The wing is tested in a subsonic, low turbulence wind tunnel at the free stream Reynolds number of 2.3×10⁵ for various angles of attack ranging from α = 0° to 45°. The baseline wing model is attached to a fence of different diameters of 1.5 and 2.5 mm at a plane equal to the root and tip chord. There are pressure ports spread across the span of the wing, and the corresponding surface pressure is measured using the MPS 4264 miniature pressure scanner. The surface pressure measured is analyzed further for the variation of the aerodynamic characteristics of the wing. The presence of a fence on the tapered wing forms an efficient flow control device that delays the flow separation, thereby delaying stall angles and preventing the steep transition of the favorable pressure gradient to the adverse pressure gradient at the stall. The presence of a fence on the wing surface has considerably increased the lift coefficient, and the stall is significantly delayed for a least taper ratio wing. The fence has suppressed the interaction of the leading-edge vortices with the tip vortices; thereby, the spanwise flow from the root chord to the tip chord is controlled. [ABSTRACT FROM AUTHOR]