Aerodynamic performance of thin wings at low Reynolds numbers

Purpose - This study seeks to explore the aerodynamic performance of wings with different shapes at low Reynolds numbers. Design/methodology/approach - The airfoils of these wings are made from aluminum plates, and the maximum cord length and wingspan are 15 cm. Wings A to D are plates with 6 percent Gottingen camber but different wing planforms. The forward-half sections of wings E and F are dragonfly-like, whereas the rear-half sections of wings E and F are flat and positively cambered, respectively. The aspect ratios of these wings are close to one, and the ratios of plate thickness to the maximum cord length are 1.3 percent. Experimental results indicate that the wings with Gottingen camber have a superior lift and lift-to-drag ratio, whereas the wings with dragonfly-like airfoils perform well in terms of drag and pitch moment. Findings - The aerodynamic measurements of the wings demonstrate that the wing with the Gottingen camber airfoil, a swept-back leading edge and a straight trailing edge is suitable for use in micro aerial vehicle (MAV). An MAV is fabricated with this wing and the aerodynamic performance of the MAV is examined and compared with the bare wing data. Originality/value - This study develops several criteria to the design of MAV-sized wings. For example, the thickness ratio of airfoil must be small, usually less than 2 percent. Besides, the airfoil must be cambered adequately. Furthermore, a wing planform with a swept-back leading edge and a straight trailing edge would be contributive to the successful flights of MAVs.