عنوان مقاله [English]
Today, underground coal gasification (UCG) has been seriously considered for exploitation of coal seams. The UCG method is an alternative process for converting the world’s coal resources into energy, liquid fuels and chemicals. In the UCG method, steam and air or oxygen is injected into an underground coal seam and combustible gas is produced in-situ by igniting and burning of coal. During the process of UCG, the temperature in the gasification panel may be more than 1000 °C. Thus, rocks and coal in the vicinity of the gasification panels are exposed to high temperatures. The mechanical, physical and thermal properties of rocks are modified under the influence of the temperature. An estimation of the temperature fields around the gasification panels is important for further study of the lithology and temperature expansion stresses of the rock. In this research, numerical simulation with COMSOL Multiphysics software was used to analyze the distribution of a stable temperature ﬁeld in the surrounding rocks during the process of UCG. The results showed the temperature gradually decreases from gasification panel to ambient temperatures. The heat penetrates in the roof, floor and pillar 1.7, 1.4 and 1.2 meters, respectively.