Abstract: Lightning stroke is an important reason for wind turbine blade damage, and the safety and reliability of wind turbine equipment is more prominent in comprehensive energy utilization. To improve the protection against lightning for wind turbines, an antilightning scheme that covers wind turbine blades with external conductors is designed.The effect of the scheme has been verified theoretically and experimentally. Taking the DU93-W-210 airfoil which is specialized for wind turbines as an research objective, using computational fluid dynamics (CFD) method, the influence of the external conductor diameter on the aerodynamic performance of this airfoil is studied. It is found that with the increase of the conductor diameter, the lift coefficient of the airfoil decreases linearly, and the drag coefficient of the airfoil increases linearly，and the liftdrag ratio decreases. At a 0° attack angle, the lift coefficient of the airfoil with conductor drops the most. When the diameter of conductor is 10mm, the lift coefficient decreases by 10% at the most .At a 4 °-16 ° attack angle, lift coefficient reduces slight,which is roughly 3% on average. The research conclusion can be used to guide the design of new lightning arresting system for wind turbine blades and improve the safety and reliability of wind turbine units.

Key words: comprehensive energy, lightning, safety, wind turbine, blade, airfoil, CFD