Optimal Configuration of a Rear Wing to Improve Stability and Aerodynamic Efficiency of a Sedan Using Computational Fluid Dynamics

Guevara J.A.; Rodriguez C.V.; De La Torre D.D. · International Journal of Automotive and Mechanical Engineering (2025) · DOI: 10.15282/ijame.22.4.2025.21.0998

Resumen

The rear wing mounted on a sedan’s trunk is primarily designed to enhance the car’s aerodynamics, particularly when driving at high speeds. This component generates a downward force, which increases ground adhesion, improving stability during driving. This study aims to determine the optimal configuration of a rear wing installed on the trunk of a sedan to improve its stability and aerodynamic efficiency. Using the mesh selected from the independence study, through Computational Fluid Dynamics (CFD) method, we compared the lift (Cl) and drag (Cd) coefficients, as well as the lift to drag ratio (Cl/Cd) for different rear wings shaped by NACA 4412, SD7032, E387, NASA SC(2)-0714, and S826 profiles to find their optimal configuration. The simulations include angles of attack (α) between 0 and 15° and vehicle speeds of 36, 72, 108, and 144 km/h. Subsequently, we studied the fluid behavior around the sedan with and without the rear wing. Then, the rear wing height ratios (b/H) that show the best aerodynamic performance were analyzed. Apart from the NACA 4412 profile, the profiles used here have not been previously analyzed in rear-wing applications on sedans, which adds to the value of this research. The results show that, at various driving speeds of the sedan, different rear wings achieve the best Cl. The suitable configurations are NACA 4412 at α = 9° (for 36 km/h speed), S826 at α = 7° (for 72 and 108 km/h), and NASA SC(2)-0714 at α = 10° (for 144 km/h).

Instituciones: Universidad Nacional de Ingeniería; Universidad Tecnológica del Perú