A wind tunnel experimental study of icing on wind turbine blade airfoil

Icing on the blade surfaces of wind turbines is a serious problem in cold regions, which greatly affects the performance of wind turbines. To verify the characteristics of surface icing, wind tunnel tests were carried out on the wind turbine blades with the NACA7715 airfoil. The chord of the blade is 0.22 m, and the height of blade is 0.2 m. There is a water spray nozzle set in the outlet of the wind tunnel to supply fog with different diameters of water-drops and different flow of discharge. The flow of discharge can be controlled by a flow controller. Wind tunnel tests were carried out in the winter as the cold air outside can be induced into the wind tunnel. The icing distribution of the blade under different wind speeds and attack angles were obtained by camera. Furthermore, the icing rate and icing area icing were calculated and analyzed. The main test results show that the maximum icing rate of NACA7715 is 6.6%, and the maximum icing area ratio is 21.8% at the attack angle of −80°.