Improving the capability of k-ω SST turbulence model for predicting stall characteristics of airfoil

Two-dimensional numerical simulations of NREL airfoil S825 with k-ω SST turbulence model were conducted. For the k-ω SST turbulence model could not predict the airfoil aerodynamic performance accurately at stall conditions, the non-equilibrium turbulence transport nature was systematically analyzed. It was found that: the mis-predicting of the stall characteristics was due to the fact that the tradition turbulence model could not accurately predict the strongly non-equilibrium turbulence transport nature. Correcting the constant a₁ or β_∞^* could improves obviously the capability of prediction stall characteristics of k-ω SST turbulence model, because by giving a more reasonable turbulence transport nature, the capability of k-ω SST model in capturing the non-equilibrium turbulence was improved notably.