Abstract: Aiming at the wind turbine blade icing problem, the NREL Phase VI wind turbine was used as the research object. The Fluent and the aero-elasticity program FAST were used to study the load effects of the asymmetry icing (i.e., just one blade is covered with ice) and the symmetry icing (i.e., two blades are covered with ice). Results show that the icing can decrease the blade aerodynamic performance, its rotor torque will be decreased. The symmetry icing can decrease the rotor torque up to 34.99%. The asymmetry icing can induce the unbalance shear force on the low speed shaft, and will increase the low speed shaft fatigue load. The symmetry icing can decrease the rotor thrust, the blade root moment and the tower base moment up to 6.07%, 40.32% and 37.32%, respectively.

Key words: wind turbine, blade icing, load