Prediction of Airfoil Stall Based on a Modified k − v 2 ¯ − ω Turbulence Model

The accuracy of an airfoil stall prediction heavily depends on the computation of the separated shear layer. Capturing the strong non-equilibrium turbulence in the shear layer is crucial for the accuracy of a stall prediction. In this paper, different Reynolds-averaged Navier–Stokes turbulence models are adopted and compared for airfoil stall prediction. The results show that the separated shear layer fixed k − v 2 ¯ − ω (abbreviated as SPF k − v 2 ¯ − ω ) turbulence model captures the non-equilibrium turbulence in the separated shear layer well and gives satisfactory predictions of both thin-airfoil stall and trailing-edge stall. At small Reynolds numbers ( R e ~ 10 5 ), the relative error between the predicted C L , m a x of NACA64A010 by the SPF k − v 2 ¯ − ω model and the experimental data is less than 3.5%. At high Reynolds numbers ( R e ~ 10 6 ), the C L , m a x of NACA64A010 and NACA64A006 predicted by the SPF k − v 2 ¯ − ω model also has an error of less than 5.5% relative to the experimental data. The stall of the NACA0012 airfoil, which features trailing-edge stall, is also computed by the SPF k − v 2 ¯ − ω model. The SPF k − v 2 ¯ − ω model is also applied to a NACA0012 airfoil, which features trailing-edge stall and an error of C L relative to the experiment at C L > 1.0 is smaller than 3.5%. The SPF k − v 2 ¯ − ω model shows higher accuracy than other turbulence models.