3D numerical simulation of aerodynamic performance of iced contaminated wind turbine rotors

Wind turbines often suffer from blade icing issues in cold regions, which causes the degradation of the blade aerodynamic performance and the loss of power production. In the paper, a 3D numerical simulation model of the wind turbine rotor is put forward by using a commercial computational fluid dynamics (CFD) solver ANSYS Fluent to estimate the blade aerodynamic performance after icing. The multiple reference frame (MRF) model, Reynold Averaged Navier Stokes (RANS) and k-ω SST turbulence model are used in the simulation. Results show that CFD computational results are in accordance with the experimental results for clean and rime-iced rotors within rated wind speed, and overrated for glaze-iced rotors at high wind speed. As the wind speed increases, the rotor speed and output power of wind turbines decrease more dramatically under icing conditions. Besides, ice shapes mainly affect pressure distribution at the leading edge of airfoils, and thus reduce the normal force and tangential force significantly at approximate 62%-89% radial position. Influenced by ice shapes, blades are more likely to work in stall region at the same wind speed. In addition, flow separation around the iced blade is more serious at larger wind speed, which will produce more momentum and frictional loss, especially for glaze ice. The results provide a valuable reference for the wind farms operation and generator system evaluation in cold regions.