Computational evaluation of cooling system under deep hot and humid coal mine in China: A thermal comfort study

Cooling system is widely used in deep coal mines of China for the increasing heat hazard. Although the greatly controlled air temperature and relative humidity ensured a certain degree of production safety by utilizing of cooling systems, especially by High temperature Exchange Machinery System (HEMS) system, the working conditions are still complained by the workers. An evaluation of the cooling system basing on the thermal comfort was necessary. In this article, onsite experiment and numerical simulation were taken and the cooling effect of HEMS system was evaluated by the index of WBGT. The results indicated that the current outlet parameters (outlet air temperature, RH and velocity respectively are 18 °C, 80% and 1.5 m/s) of the air cooler would not make the workers in all of the tunnels feel comfortable; the RH in the inlet tunnel that reduced to 75% and in the mining tunnel reduced to 60% would satisfy all of the workers in the whole tunnel. The results would be beneficial to the optimizing of cooling under deep coal mine.