Two-Dimensional Aerodynamic Analysis of Multiple-Elements Airfoils Using Computational Fluid Dynamics (CFD) Software

Multiple-element airfoils consist of two or more airfoil sections positioned closely together, and they are commonly used to enhance lift during takeoff and landing. These configurations can be found in aircraft wings and wind turbines because of their ability to generate greater lift and improve aerodynamic performance. However, optimizing their arrangement can be challenging, as suboptimal configurations may lead to increased drag. This study examines three multiple-airfoil configurations: (A) NACA 2412–NACA 0012, (B) NACA 2412–NACA 2415, and (C) NACA 2412–Clark Y. Computational fluid dynamics (CFD) simulations were conducted using ANSYS Fluent with the Spalart–Allmaras turbulence model at a Reynolds number (Re) of 1.34 × 10⁶ and a velocity (V) of 20 m/s. The lift and drag characteristics were analysed for angles of attack (ranging from 0° to 19°). The results indicate that all configurations exhibit similar trends in lift and drag; however, Set C demonstrates a delay in stall, while Sets A and B achieve the highest lift-to-drag ratio (approximately 32) at an angle of 5°. These findings enhance our understanding of the performance of multi-element airfoils and their role in improving aerodynamic efficiency during takeoff.