Investigation into spontaneous combustion hazard and numerical simulation of nitrogen injection fire prevention effects in the roof coal
Abstract：Abstract：In order to theoretically understand the law of temperature rise due to spontaneous combustion in caving zone of roof coal in coal mine roadway, and identify the location of hazardous region and studied the fire prevention effects by nitrogen injection, the sofluare FLUENT was used to solve the stable state of air leakage speed and oxygen concentration,dynamic temperature distribution and cooling effects brought by nitrogen injection in the high caving zone based on the assumption that coal oxidation rate accords with Arrhenius law. The computation results indicate that the temperature rise reflects a slow-accelerating process and the portion close to roadway has lowest temperature while the deep portion comes next, the top temperature region lies in the middle part of caving zone and deviates to inlet. The rate of temperature rise in high temperature region accelerates both by the increasing air velocity in roadway and increasing porosity when practical size is kept unchanged. The nitrogen injection in high temperature region can lead to obvious cooling effects for the reason that the temperature close to injection hole decreases dramaticlly after short time and cooling effects extend towards part of the middle and outlet gradually.
Keywords：nitrogen injectionspontaneous combustioncaving zoneFLUENThigh temperature region
Publication Date：2012-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：6( 1015-1020 )