The issue of wind turbine icing under the mixed-phase of ice crystals and supercooled water droplets is studied. The mechanism of wind turbine mixed-phase icing is analyzed, and the numerical simulation of airfoil icing on wind turbines is carried out. A particle motion trajectory equation is established using the Lagrangian method. The solution method for the control equation and the relevant definition of the collection coefficient are provided. A new mathematical model for icing under mixed-phase conditions is proposed, and the mass and energy conservation equations for liquid water on the surface of a wind turbine airfoil under mixed-phase conditions are established. The mathematical expressions for each equation are provided, and the physical phenomena of ice crystal adhesion and erosion are analyzed. The solution method for the icing growth model is provided. The accuracy of the icing model method proposed in this paper is demonstrated through comparison with experimental results. The icing characteristics of wind turbine airfoil surfaces under mixed-phase conditions are studied, and the impact of various initial parameters on icing characteristics is investigated. The research results indicate that erosion phenomena can affect surface icing. As the erosion rate increases, the surface icing decreases. The higher the adhesion coefficient and melting ratio, the greater the amount of icing. Different temperatures can lead to the formation of various ice forms on the airfoil. Rime ice forms at higher temperatures, while glaze ice forms at lower temperatures. However, with the increase in ice crystal content and diameter, the range and amount of icing change less. The research work provides a foundation for further research on wind turbine icing under mixed-phase icing conditions and the design of anti-icing and de-icing systems.

wind turbines  /  airfoils  /  wind turbine blades  /  numerical methods  /  icing  /  mixing-condition  /  ice crystal