Numerical study of the aerodynamic performance of a NACA0012 airfoil fitted with inclined backward-facing steps

Abstract The study aims to enhance the aerodynamic performance of a NACA0012 profile by utilizing backward-facing steps inclined forward, inspired by shark denticles known for delaying boundary layer separation. The turbulent and steady-in-the-mean flow around the airfoil fitted with inclined backward-facing steps (IBFSs) is numerically investigated via Ansys Fluent. In this work, the effects of characteristic geometrical parameters of the IBFSs like the step height, the inclination angle and the layout of the steps along the airfoil suction surface on the lift and drag coefficients are brought to light. The results demonstrate a notable enhancement in aerodynamic finesse, showing an improvement of up to 4.53% compared to the standard NACA0012. This improvement is affected by the different geometrical parameters tested. Specifically, fitting IBFSs on 80% of the suction surface and decreasing the steps height and inclination angle contributed to increased performance. The impact of IBFSs is more noticeable at high angles of attack (AOAs), where lift is significantly influenced compared to drag, while the opposite occurs at low AOA. These findings highlight the potential of the use of IBFSs for optimizing aerodynamic efficiency, particularly in scenarios characterized by high AOA.