Study on the influence of radiation heat transfer on microclimatic parameters in the blind heading of a deep potash mine

The article presents the results of a study of the intensity of air heating in the ventilation duct in a blind heading in a deep potash mine with a working air conditioning system. It is shown that the convective-diffusive heat and mass transfer model cannot accurately predict the rate of air heating in the ventilation duct considering the significant depth of mining operations. Based on experimental data, it was found that to calculate the air temperature in the ventilation duct, in addition to convective heat exchange, it is necessary to consider radiation heat exchange. A mathematical model of coupled heat and mass transfer in a blind heading, ventilation duct and surrounding rock mass is presented. The main novelty of the model is the explicit consideration of radiation heat exchange and advance of the heading face. It allows developing technical solutions for normalizing the microclimate parameters in the atmosphere of blind headings. The analysis of the simulation results for the blind headings of a potash mine is conducted. It is shown that radiation heat exchange can be the main cause of the cooling of the rock mass and has a significant effect on the thermal conditions in a blind heading. The reduction of air heating in a ventilation duct was studied when using materials with low emissivity. It is shown that the use of a ventilation duct made of galvanized steel in the considered blind heading leads to a twofold decrease in the impact of radiation heat transfer.