Construction of air flow heat transfer coefficient and calculation of airflow temperature in mine wet roadway

Aiming at the problem that the calculation of the heat and moisture exchange between the surrounding rock and the air flow is difficult to be realized in the whole mine domain system,a model of the airflow heat transfer coeffi- cient of the wet roadway is put forward. According to the measured relative humidity of airflow in the field,the change law of the airflow humidity in the mine intake airflow is obtained. The model of the heat exchange between the airflow and the surrounding rock under the influence of water evaporation in the roadway is then determined by reverse deduc- tion,and the heat transfer coefficient between the surrounding rock and the airflow is corrected. The variation law of airflow relative humidity in actual mines is described by the weighted distance of air volume. Based on the case study in Jiudaoling Mine,the algorithm is incorporated into the mine ventilation network system,and TF1M3D is used to sim- ulate the airflow temperature of the whole mine domain system on MATLAB platform. Research shows that the water evaporation of the roadway has a great influence on the airflow temperature,and the airflow temperature in the main intake air shaft section is increased by 0. 97 ℃ ,the variation range is not significant. With the increase of humidity, the variation of airflow temperature increases gradually. The results are in agreement with the measured results of the Jiudaoling Mine. The algorithm is included in the calculation of the network system,which can solve the problems of the temperature distribution simulation and the automatic calculation of the natural ventilation pressure in the thermal hazard prevention of the 3D mine model ventilation system.