Effects of Angle of Attack on the Aerodynamic Performance of NACA 2412 Airfoil: Computational Fluid Dynamics Comparison of k-ε, k-ω, and k-ω SST Turbulence Models

Abstract

The predictions of airfoil performance using computational fluid dynamics can be sensitive to the choice of turbulence model. The present study examined the effects of turbulence-model selection and angle of attack on the aerodynamic performance of a NACA 2412 airfoil. Eighteen simulations were run in SimScale with k-ε, k-ω and k-ω shear stress transport (SST) models at angles of attack from 0 to 10 degrees with 2 degree increments. All simulations were performed at a freestream velocity of 80 m/s and a Reynolds number of approximately 3.1E6. The models were validated in terms of lift coefficient, drag coefficient, lift to drag ratio, pressure and velocity contours and maximum y+ values. The most stable and accurate results were obtained using the k-ω SST model. The lift coefficient increased from 0.282 at 0° to 0.574 at 10°. This model underpredicted experimental lift values, but it produced the expected trend and predicted the highest aerodynamic efficiency among the models tested. The k-ω model also gave a generally consistent lift trend but predicted higher drag and lower aerodynamic efficiency. Conversely, the k-ε model was giving irregular and non-physical values at several angles of attack. These results demonstrate the importance of the turbulence model selection on the predicted airfoil performance and suggest that the k-ω SST was the most appropriate model for the conditions studied.