Abstract
Over 30% of wind turbines in cold regions are exposed to icing issues. The influence of glaze ice on wind turbine aerodynamic performance is unclear due to its wet nature. In this study, we conducted a series of numerical simulations to study the glaze ice induced influence on wind turbine aerodynamic properties, including lift and drag, via a commercial computational fluid dynamics (CFD) solver, i.e., ANSYS FENSAP-ICE. Specifically, the aerodynamic properties of a DU91-W2-250 turbine blade were analyzed using FENSAP. DROP3D and ICE3D to determine droplet impingement, ice accretion, and roughness profiles on the airfoil. Results showed icing accreted primarily near the stagnation point of the airfoil with runback on both the upper side and underside. At higher angles of attack, ice accretion mass increased on the underside but decreased on the upper side of the airfoil. Increasing ice accretion reduced lift coefficient and increased drag coefficient. Larger amounts of icing on the upper surface induced earlier separation of the boundary layer. The higher angles of attack resulted in less lift coefficient drop over time, due to less ice accretion on the upper surface. Ice accretion on wind turbines occurs in favorable conditions for energy production. Anti-icing minimizes the undesirable effects of icing, including power losses and mechanical failure. FENSAP-ICE simulated anti-icing conditions at various chord lengths and angles of attack. Some of these anti-icing conditions failed to completely remove icing. The heated airfoil icing primarily occurred as runback, with no ice accretion near the leading edge. More runback accreted on the underside of the airfoil as angle of attack increased. These partially iced airfoils demonstrated better aerodynamic properties than iced airfoils, where the lift coefficient decreased overtime at a gentler rate than iced conditions. Runback icing did not accrete in the wake of the airfoil, causing the separation of the boundary layer to remain in the same location.