Abstract
Wind turbines have recently been erected in mountainous regions with potentially high wind energy in view of their economical operation.Icing may occur on wind turbine blades when super-cooled liquid water droplets in fog and clouds collide with them.Ice accretion on the wind turbine blades would deteriorate the stable operation of the turbine because it may exert aerodynamically and mechanically the negative influences due to the changes of shape and mass of a blade.Therefore, it is important to estimate the effect of icing on power production and the lifetime of a wind turbine prior to planning its construction in regions prone to icing.Measures to prevent icing on the turbine blade must be taken into account if a wind turbine is likely to suffer from various kinds of icing events. In the light of the aforementioned factors, a code for numerically calculating the ice accretion along a wind turbine blade was developed.In order to reduce the computational burden, an icing code for a two-dimensional airfoil, assuming a potential flow around the airfoil, was employed for each blade element based on the strip theory.The induced velocity at the rotor rotational plane of the wind turbine was calculated by applying the generalized momentum theory and blade element theory.The calculation results were examined by comparison with results from icing wind tunnel tests using two-dimensional airfoil models and the shape of ice accretion from field measurements.It was observed that the newly developed icing code for the wind turbine blade could properly estimate the ice accretion.
