Experimental and numerical simulation and study of spontaneous combustion characteristic of coal piles

doi:10.16265/j.cnki.issn 1003-3033.2021.12.010

Abstract

Abstract: In order to study spontaneous combustion characteristics of trapezoidal coal piles, and to build a remote monitoring system of coal pile temperature, based on theories of fluid dynamics and heat and mass transfer of porous media, a multi-field coupling mathematical model for spontaneous combustion of coal piles was established by using temperature distribution function on the windward side of the stockpile, and variation situations of temperature with wind speed under conditions of different porosity of coal piles were simulated. The results show that at a certain porosity, when wind speed is low, the maximum internal temperature of the pile and that of coal 0.75 m deep increase along with that of wind speed. But for the condition of a higher wind speed, their temperature gradually decrease with the increase of wind speed. Under the same external environment, the lower the porosity is, the harder it will be to cause spontaneous combustion, but considerations should be given to conditions around coal piles.

Key words: coal pile spontaneous combustion, porosity, numerical simulation, speed of air leakage, heating rate

CLC Number:

X936

QU Guona, LI Hongjian, JIA Tinggui, QIANG Qian, WANG Laigui. Experimental and numerical simulation and study of spontaneous combustion characteristic of coal piles[J]. China Safety Science Journal, 2021, 31(12): 69-77.

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