Study On Characteristics Of Heat And Mass Transfer In Working Face Of High-temperature Mine

With the continuous extension of the coal mining depth, the mine problem of high temperature can not be ignored. Study on characteristics of heat and mass transfer in the coal mining face and heat transfer mechanism between the coal wall and the airflow, the thermal hazard control of the working face, effective regulation of high-temperature environments coal face and create in the underground work environment compliance with established safety procedures is of great significance.This article analyzed the theory of heat and mass transfer, the mathematical model of heat transfer of wet wall was established. The simultaneous equations wereestablished in this research on heat transfer betweenmoist wall and wind. It included the overall heat transfer equation using the sensible heat and latent heat differential expression and differential expression denotes of the total heat transfer equation using the unstable heat transfer coefficient and other heat.The theoretical unstable heat transfer coefficient relationship was obtained. Based on the theoretical analysis, measured the meteorological parameters of mining face,influence of mine air temperature during different production periods,humidity, variation of heat and season for mine air were analyzed.According to the actual parameters of the mine,related to the theory of heat and mass transfer andsimilarity theory, model of physics experiment of mine working face was built. Setting test parameters, simulating the distribution of temperature and humidity of the working face, the characteristics of heat and mass transfer between wet wall and airflow at the face was obtained.This Latent heat was about four times the size of the sensible heat in the heat transfer between wet wall and airflowwas obtained in this paper.Analyzing the variable relationship of unstable heat transfer coefficient with relative humidity, wind speed, air temperature and wall temperature, the change of the unstable heat transfer coefficientdepends largely on the change of latent heat in the wind wassummarized. Furthermore, analyzing theorthogonal experiment, the influence degree of different factors on the unstable heat transfer coefficient was got:Relative humidity> wind speed> wall temperature>Airflow temperature.Finally, according to the theoretical research and experimental study of unsteady heat transfer coefficient, comprehensive consideration the effect of various parameters on the unstable heat transfer, fitting out the relative humidity of into the wind at 80% and 90% on the figure of unstable heat transfer coefficient, provided the basis for calculating cooling load of the mine.