Analysis And Research On The Characteristics Of Heat And Moisture Exchange Between Tunnel Surrounding Rock And Air Current

With the development of coal industry and its increasing mechanization, the depth of coal mining increases year by year, and there is more and more mine heat injury, which is greatly hazardous to miners’health and to coal production. To the air current in the mine, there are many kinds of heat source, of which the heat from surrounding rock is one kind of the most important ones. Specialized study on the mechanism and laws of the exchange of heat and moisture between surrounding rock and air current is significant to promote the ability to predict the temperature of the air current in mine.In this paper, through studying and analyzing the related theories on the exchange of heat and moisture between surrounding rock and air current, based on the unsteady heat exchange coefficient, the model of the exchange of heat between surrounding rock and air current is established. Combining two cases and under the environment of Machematica, the relevant parameters are analyzed on the change of the temperature of air current, including wall roughness, perimeter of the roadway section, mass flow of the air, thermal conductivity of the rock, the change of the humidity of the air which is carried out a detailed analysis and discussion. Under the environment of FLUENT, the model, according to the instance, is established to analyze the features of the method of numerical simulation in the calculation on the exchange of heat between surrounding rock and air current.It shows that wall roughness has little effect on the exchange of heat between surrounding rock and air current, perimeter of the roadway section and thermal conductivity of the rock have a certain one, mass flow of the air has a significant effect and the change of the humidity of the air is quite strong. And the rise of the temperature of the air current when flow mass is reduced is more notable than the abate of the temperature of the air current when flow mass is added to. It is not suitable to predict or calculate the air temperature in mine using numerical simulation method. It is proposed to calculate the air temperature in mine using form method which is used in the calculation of mine ventilation resistance.