Accurate aerodynamic characterization of wind turbine airfoils is important for optimizing rotor performance, particularly at high Reynolds numbers where phenomena such as stall and transition significantly affect lift and drag. This study presents a nested Krylov subspace solver implemented in the SU2 open-source CFD solver to accelerate steady-state Reynolds-Averaged Navier–Stokes (RANS) simulations. The approach combines Flexible GMRES (FGMRES) with BiCGSTAB as an inner solver preconditioned by LU-SGS. The methodology is applied to airfoils of the NREL 5-MW reference wind turbine, including NACA64-618, DU91-W2-250LM, and DU99-W-405LM, over various angles of attack and high Reynolds numbers. Grid convergence studies are performed, and aerodynamic coefficients are evaluated at root, mid, and tip sections. The nested solver achieves faster convergence and lower computational cost compared to standard solvers, particularly near stall conditions. These results confirm its effectiveness for reliable airfoil database generation and efficient blade design.