Triangular and semi-circular serrations in raked winglets: Numerical analysis of vortex dynamics and drag control

The present study explores the aerodynamic performance of serrated raked winglets (SRWs) through detailed computational fluid dynamics analysis, focusing on drag reduction, lift enhancement, and overall efficiency improvements. Utilizing the National Advisory Committee for Aeronautics (NACA) 653218 airfoil, simulations were conducted across a range of angle of attack using a realizable k–ε turbulence model. The study investigates the impact of key parameters, such as serration geometry, count, and spanwise placement on the aerodynamic characteristics. Results reveal that SRWs outperform conventional and raked winglet designs, achieving up to a 14.5% improvement in the lift-to-drag ratio (L/D) at higher angles of attack, with a 15% reduction in drag compared to a conventional wing. The incorporation of serrations was found to effectively minimize wingtip vortex intensity and turbulence, contributing to enhanced flow stability and reduced energy losses. A comparative analysis of triangular and semi-circular serrations highlights the superior vortex suppression capabilities of triangular designs, particularly when positioned near the wingtip, leading to a 6% higher L/D ratio than semi-circular configurations. These findings underscore the potential of SRWs as a transformative wingtip device for optimizing aircraft aerodynamic performance and fuel efficiency, offering valuable insight for future experimental and computational studies in advanced winglet design.