Investigation of the effect of turbulence models for CFD simulations of dynamic airfoils

This study presents a numerical investigation into the aerodynamic behavior of a pitching NACA 0012 airfoil under dynamic conditions. The analysis was carried out using a sliding mesh method in Fluent, incorporating sinusoidal pitching motion with various turbulence models, including SST, SST with intermittency, and Transition SST. The effects of different turbulence models on the aerodynamic performance of the airfoil at various angles of attack (AoA) were studied, focusing on the pressure coefficient (Cp), flow structure, and laminar separation bubble (LSB) formation. Additionally, the results for pitch-up and pitch-down motions were compared to evaluate the hysteresis effects and dynamic flow behaviors. The study found that the SST model exhibited inviscid flow characteristics, while the SST with intermittency and Transition SST models captured the boundary layer behavior more effectively, including the separation and reattachment processes. Significant differences were observed in the Cp distribution and turbulence characteristics, with pitch-down motion resulting in higher Cp values and more complex flow phenomena. The results contribute to the understanding of aerodynamic behavior during dynamic motions, offering insights into the role of turbulence models on airfoil performance.