Distribution Regularity and Numerical Simulation Study on the Coal Spontaneous Combustion “three zones” Under the Ventilation Type of Ventilation Type of Ч + J

Taking Wang Tai Coal Mine2304 working surface as the object of study, the gaseous components along with the advancing working face were examined through burying pipe sampling in the goaf, the change rule of oxygen volume fraction along with the depth of working face was investigated. According to the measure result of gas concentrations, this paper determined the distribution of coal spontaneous combustion oxidation “three zones” in Wang Tai Coal 2304 working face. At the same time, based on the Darcy law, the numerical simulation was performed for the single return air roadway by using the Fluent software, 80m, 160m and 240m away from the working surface respectively. In the three situations, the paper researched the distribution of flow field, the O2 concentration field and the CO concentration field, analyzed the change rule of oxidation zone along with the advancing working face. Wang Tai Coal 2304 working face contain spontaneous combustion “three zones”: cooling zone (0∼38m), oxidation zone (38m∼145m) and suffocation zone (> 145m); the width of oxidation zone along with single return air roadway from the face length approximately linearly increases.