Ice formation on wind turbine blades poses dual challenges to the operational safety and power generation efficiency of wind farms, making it urgent to de-ice wind turbines with severe icing. Air thermal deicing is an active anti-icing technology for blades, where hot air transfers heat from the inner surface to the outer surface of the blade through a combination of conduction and convection, melting the overlying ice layer. From the perspective of the heat transfer process alone, the processes of convective and conductive heat transfer in air thermal deicing are not particularly complex and can be studied through two methods: systematic experimentation and numerical simulation, to investigate their flow and heat transfer characteristics. However, the conditions required for experimentation are quite demanding, and the experimental costs are relatively high. To address this issue, a coupled flow and heat transfer model for both the inner and outer sides of the turbine blade is established based on technologies such as the k-ε turbulence model, velocity-pressure coupling algorithm, and wall function. This model analyzes the effectiveness of air thermal deicing under the combined effects of conduction and convection, avoiding the separated defects of traditional numerical models that only consider unilateral flow and heat transfer. It can accurately obtain the velocity field, temperature field, pressure field inside the blade cavity, as well as the temperature distribution on the outer wall of the blade under specific operating conditions, providing technical guidance for the design and operational control of a reasonable deicing system. The research results indicate that under different air supply velocities, the temperature distribution on the blade surface shows a trend of being higher at both ends and lower in the middle, and as the air velocity increases, the temperature imbalance phenomenon is significantly improved. When the air supply velocity is less than 15 m/s, the surface temperature of most areas of the blade is below 0 ℃, but when the air supply velocity increases to 20 m/s, the area with a surface temperature below 0 ℃ is significantly reduced.