Abstract: Aiming at the problems of high temperature and high humidity in coal mining facing, this paper studies the heat distribution law of coal mining facing, compares and analyzes the enthalpy difference method and Sigma thermal difference method to calculate the air supply volume. Based on this, mechanical cooling scheme is scientifically formulated, and the cooling effect is verified by numerical simulation method. The results show that: the air supply calculated by Sigma heat is more accurate than that by traditional enthalpy difference method, and the air supply is 22.4 kg/s, that is, 1 041.6 m³/min. It can be seen from the simulation results that the RWK350 air cooler can achieve effective cooling below the Coal Mine Safety Regulations at both the common 10 m and 15 m air duct outlet locations, thus achieving effective cooling of the driving roadway.