Numerical Simulation Of Three Zone In Airflow Field Of Gob Areas And Its Application In Preventing Spontaneous Combustion

In recent years, the top-dropping method of fully methanized coal mining is broadly adopted in the coal industry. As the volume of roof cave-in is huge,the coal left in the gob is in a large quantity arid air leakage is significant, the danger of coal spontaneous combustion in gob is realistic and seirous. The spontaneous combustion of coal in gob is the main reason for mine fire and this paper through three important physical of gob, quantity wind speeds, the oxygen density, the temperature quantitative research discovers the rule of the influence spontaneous combustion and provides the beneficial reference value to prevent the coal spontaneous combustion and the mine fire.This paper based on non-homogeneous flow continuity equation, multi-component gas-diffusion equation and the integrated heat transfer in porous media equation, establish the equation of gob gas flow in a unified mathematical model.Then discretized using finite volume method, combined with the actual conditions of the site and finally using the CFD software simulated the 3318 workface of Xing Fu Coal Mine in Fu Xin province.Simulation process in accordance with gob caving broken expansion coefficient of the distribution, simulation process in accordance with gob caving broken expansion coefficient of the distribution, respectively, of its nitrogen injection and the absence of simulated nitrogen injection, when two kinds of cases come to face 3318 "three-zone" the size of the oxygen concentration distribution,the most slow speed the workface advances must satisfy...