Sensitivity analysis of key parameters for full-blade icing of wind turbines during rotation

Blade icing critically constrains the efficiency and safety of wind turbines in cold and offshore regions, yet the spatial characteristics of full-blade icing under rotation, the parametric sensitivity of icing-induced aerodynamic degradation, and the mechanism of leeward icing remain insufficiently understood. This study develops a numerical framework coupling Fluent with FENSAP-ICE, in which Moving Reference Frame and dynamic-meshing techniques enable three-dimensional rotating simulations of airflow, droplet impingement, water-film migration, phase-change icing, and aerodynamic evaluation. At −10°C, rotational speed, inflow velocity, liquid water content (LWC), and median volume diameter (MVD) are varied parametrically, and response surface methodology quantifies spanwise sensitivities of icing and lift-to-drag ratio degradation. Wind velocity governs aerodynamic deterioration most strongly near the blade tip, with LWC secondary, whereas LWC dominates at mid-span, where wind velocity and droplet size show comparable secondary significance, indicating pronounced rotation-induced radial differences. Leeward icing stems mainly from windward water films transported into the leeward low-pressure separation zone by aerodynamic shear, centrifugal force, and gravity, rather than direct droplet impingement, and intensifies with larger droplets. Icing reduces the tip lift-to-drag ratio by up to 80% and shifts the optimal angle of attack, informing ice warning, zonal anti-/de-icing design, and operational control.