Bilateral Leading-Edges with Tubercle Modifications

The demand for improved aerodynamic performance and maneuverability across vehicles, propellers, and wing designs continues to grow. Inspired by nature, tubercle airfoils based on the humpback whale’s flipper have gained significant attention. This study experimentally evaluated bilateral tubercle leading-edge airfoils derived from a modified NACA 0018 design (chord length: 1.82 in, span width: 7.5 in, amplitude: 6.3c%). Five configurations 8T, 14T, 16T, 20T, and 24T were tested in a 12 x 12 x 36-inch test section at 13 m/s and angles of attack from 0° to 20°. Results showed the 20T airfoil achieved the best lift-to-drag efficiency, followed by the 24T and 16T, while the 14T showed moderate improvements over the baseline. These findings highlight the aerodynamic benefits of tubercle configurations in enhancing lift and improving stall resistance, offering potential for applications requiring stable performance across a wide operating range.