This study investigates the aerodynamic characteristics of the NACA 4412 airfoil using the finite element method under different flow models. A three-dimensional wing section with NACA 4412 geometry was modelled, and the flow was simulated using four commonly employed models: k-omega shear stress transport, k-epsilon, laminar, and inviscid. For each flow model, the angle of attack was varied over a fine range covering prestall, stall, and poststall conditions, and the corresponding lift and drag coefficients were obtained and plotted. The sensitivity and accuracy of the flow models in simulating the behavior of asymmetric airfoils were compared to the expected behavior derived from Navier–Stokes, Euler, and related viscous and nonviscous flow formulations. Particular emphasis was placed on predicting flow separation, resolving the boundary layer close to the airfoil surface, and estimating viscous drag. The results show that the k-omega shear stress transport model most accurately captures the onset of stall, the maximum lift level, and the development of flow separation around the NACA 4412 profile. The k-epsilon model provides acceptable results in fully turbulent regions but predicts stall at higher angles of attack and is less precise near the boundary layer. The laminar and inviscid models fail to reproduce a clear stall region and underestimate drag 23 because the turbulence and viscous losses are not represented adequately. Although the turbulence models require higher computational effort than laminar and inviscid approaches, their superior performance in predicting lift, drag, and stall behavior supports the use of advanced turbulence modelling for reliable aerodynamic analysis and design of airfoils similar to NACA 4412.
Gurkan Ortamevzi (Sun,) studied this question.