Determination on initial coal spontaneous combustion area of coal pile based on COMSOL Software

In order to prevent and control spontaneous combustion on the coal piles under different pile parameter conditions, based on the spontaneous combustio n theory of the coal pile, COMSOL Multiphysics 5.0 numerical simulation software was applied to establish a spontaneous combustion model of the coal pile. When the p orosity was 0.2~0.6, the most easy spontaneous combustion air velocity range of the coal pile, the combustion period and the initial spontaneous combustion location of the coal pile within the air velocity range of the most easy spontaneous combustion were studied. The result showed that with the porosity of the coal pile increased, the spontaneous combustion air velocity range of the coal pile would be steadily decreased. The min and max value of the spontaneous combustion period of the coal pile would have an variation tendency with increasing firstly and then reducing. Under the wind speed range of spontaneous, the most easily spontaneous combustion positio n for different porosity coal pile have a migration law of "the middle of the left side-central middle and top part-top of the right side"with the wind velocity increasing. Th e initial spontaneous combustion locations would have the generality and all would be in a location with the same coordinate. The results could provide the beneficial re ferences to accurately set the location and control of the coal pile spontaneous combustion.