The numerical and experimental investigation of aerodynamic characteristics of a bio-inspired dolphin-nose airfoil

Abstract

Stall of a wing significantly limits aerodynamic performance by causing a sharp reduction in lift and a rapid increase in drag at high angles of attack. Although bio-inspired flow-control concepts, such as tubercles and riblets, have been widely studied, cetacean-inspired nose modifications remain relatively underexplored, particularly with experimental validation. In this study, the aerodynamic performance of a dolphin-nose-modified NACA (National Advisory Committee for Aeronautics) 0012 airfoil is investigated using combined computational and experimental approaches. The modification is implemented by embedding a micro-cylinder at the leading edge to form an extended rounded nose geometry. A parametric numerical study is carried out by varying the axial and vertical positions of the micro-cylinder to generate different nose lengths and nose angles. An optimized configuration is subsequently identified and tested experimentally in a low-speed wind tunnel. The modified airfoil exhibits delayed stall, higher maximum lift, and reduced drag near stall compared to the baseline NACA 0012 airfoil. The experimental measurements show good agreement with the numerical predictions. The results indicate that dolphin-nose-inspired leading-edge modifications can serve as an effective passive flow-control approach to improve the stall characteristics of a wing.