Numerical Investigation of Dynamic Icing of Wind Turbine Blades under Wind Shear Conditions

In the wind shear icing environment, the periodically varying inflow conditions experienced by wind turbine blades can significantly enhance the dynamic icing characteristics, which poses a great challenge to wind turbine icing research. To investigate this phenomenon, the Improved Multi-Shot Icing Computational Model (IMSICM) is utilized. In IMSICM, an efficient dynamic icing computational frame is designed by using the 3D Free Wake Lifting Line method coupled with the 2D Viscous and Inviscid Interaction method to calculate the flow field. Meanwhile, the Lagrangian method is applied to compute the water droplet impingement information and the Messinger Model is used to simulate the ice growth. After validation of IMSICM by the icing wind tunnel experimental results, the wind shear icing processes of the NREL 5MW wind turbine under different wind shear conditions are analyzed. The results show that different from the linear growth behavior of Rime ice, the nonlinear features of Glaze ice development are significant. The wind shear effect has a greater impact on the Glaze ice shape, mainly manifested as the ice protrusions behind the main ice horn are suppressed. This phenomenon is mainly due to the combined effect of water impingement shadowing and heat transfer reduction.