A two‐dimensional quantitative parametric investigation of simplified surface imperfections on the aerodynamic characteristics of a NACA 63 3 ‐418 airfoil

The aerodynamic performance of a NACA 63 3 ‐418 airfoil has been analyzed with disturbances in approximately 1000 different configurations focused on the frontal 10% of the airfoil. The configuration parameters are based on field test samples and rain erosion test specimens. The most important trends are presented by 500 configurations each simulated for 6°, 8°, and 10° angle of attack. The simulations are performed with the DTU Wind Energy in‐house 2D CFD Reynolds‐averaged Navier–Stokes solver, EllipSys2D, combined with the e N transition model for the laminar‐turbulent boundary layer transition. The configurations are modeled by a direct geometrical modification of the airfoil shape. The results show that the most important parameters are the position and the depth/height of the disturbance, with up to 35% lift reduction and 90% lift/drag reduction within the specified angle of attacks and disturbance parameter ranges.