Tubercles on the leading edges of humpback whale flippers enhance the maneuverability during the pray capture. Tubercles may therefore be functional adaptations. Inspired by the effects of tubercles on flipper performance, the lift coefficient, drag coefficient, stall angle and vorticity distribution of three dimensional symmetrical wings with tubercles on the leading edge, are numerically studied by using CFD software STAR-CCM+. In order to study the effects of size, pitch as well as the aspect ratio on the wing performance, 6 different wing models (NACA0012 (AR=1, 2, 3) and NACA0012M (AR=1. 2. 3) with the same chord length equal to 12cm and at the Reynolds number 120,000 were studied. The simulation results of tubercle wings are then compared with those of the baseline NACA0012 and the experimental data obtained in low speed wind tunnel. Our numerical results show good agreement with experimental data. At the angles of attack lower than the stall angle of the baseline wing, the modified wings give reduced lift. However, at larger angle of attack where the lift generated by the modified wings is significant higher than the baseline wing the drag is substantially reduced. In conclusion, by adding tubercle on the leading edge of wing the performances can be substantially adequate.

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