缓斜煤层下行通风采空区自燃危险区域预测模型  

Prediction model for spontaneous combustion hazard zone in downward ventilation gob of gently inclined coal seam

作　　者：张增辉 ZHANG Zenghui(National Energy Group Shendong Coal Group Baode Coal Mine,Baode 036600,China)

机构地区：[1]国家能源集团神东煤炭集团保德煤矿,山西保德036600

出　　处：《煤矿安全》2023年第12期73-79,共7页Safety in Coal Mines

摘　　要：为分析不同自燃特性缓倾斜煤层工作面下行通风时采空区内具有自燃危险可能的区域的分布特征,建立了倾斜采空区的渗流模型,依据该模型利用CFD仿真得到了不同火源时(模拟采空区遗煤不同的自燃性强弱)下行通风采空区内氧气和温度场的分布特征;结合保德煤矿81309工作面现场观测的采空区不同区域的O_(2)体积分数的数据对仿真结果进行验证。结果表明:随着设置的热源强度(采空区遗煤自燃倾向性)的提高,采空区火风压作用增强,下行通风时的采空区内进、回风侧氧化带宽度差值在逐渐减小。实测得出的进、回风侧及工作面中部对应的采空区内窒息带临界位置分别距工作面200、290、175 m,与火源功率65 W/m2时的仿真结果较为吻合,表明所建立的模型较为准确,可用于倾斜易自燃煤层工作面自燃分布的研究。To analyze the distribution characteristics of regions with potential spontaneous combustion hazards in the goaf under descending ventilation in gently inclined coal seams with different spontaneous combustion tendencies,a seepage model of the inclined goaf was established.Based on this model,CFD simulation was utilized to obtain the distribution characteristics of oxygen and temperature fields within the descending ventilation goaf under different fire source conditions(simulating the spontaneous combustion tendency of coal left in the goaf).Finally,the simulation results were validated by the data of O_(2) volume fraction in different areas of goaf observed at 81309 working face of Bade Coal Mine.The results show that with the increase of heat source intensity(spontaneous combustion tendency of coal left in goaf),the effect of fire air pressure in goaf is enhanced,and the difference of oxidation zone width between the inlet and return air sides in goaf is gradually reduced.The measured results show that the critical positions of the choking zone in the goaf corresponding to the inlet and return air side and the middle of the working face are 200,290 and 175 m away from the working face,respectively,which are consistent with the simulation results when the fire source power is 65 W/m2,indicating that the established model is more accurate and can be used to study the spontaneous combustion distribution of the working face of inclined coal seam prone to spontaneous combustion.

关 键 词：自燃倾向性 下行通风 自燃危险区域 采空区渗流模型 数值模拟 

分 类 号：TD752.2[矿业工程—矿井通风与安全]