根据段王煤矿150405工作面采空区的实际尺寸,用Gambit构建了简化的煤层倾斜角度为6°的三维物理模型;采空区垮落是非均匀分布的,垮落碎胀系数及孔隙度分布按"O"形圈分布模型建立,并考虑重力因素;根据煤样封闭耗氧实验获得煤的耗氧速率,以此实现煤的非均匀耗氧源项的设置.结合段王煤矿150405工作面的实际情况,应用具体模型进行数值模拟,将模拟结果与实测数据进行对比分析,验证模拟结果的可靠性.通过改变瓦斯抽采流量的模拟,得出瓦斯抽采强度对煤自燃存在影响,随着瓦斯抽采强度的增大,采空区最高瓦斯浓度减小,自燃氧化带宽度在胶带巷侧有缩小趋势,在轨道巷侧有增大趋势.%A simplified 3-d model with coal seam dip angle of 6°was constructed with Gambit according to the actual size of the mined-out area of 150405 working face in Duanwang Mine;the caving in the mined-out area was in a nonuniform distribution, the expansion coefficient and porosity distribution of the caved material were established according to the "O-ring" distribution model and by taking the gravity factor into account;based on the oxygen consuming rate obtained by the closed oxygen consumption experiments of coal samples, the setting of the nonuniform oxygen consumption iterms of coal was achieved.Combined with the actual situation of 150405 working face in Duanwang Mine, numerical simulation was conducted by the concrete model, the simulated results were then compared with the measured ones in order to verisfy their reliability.The influence of gas drainage intensity on the coal spontaneous combustion was obtained by simulating the change of gas drainage amount, with the increase of gas drainage intensity, the maximum gas concentration in the mined-out area decreased, and the width of the self-ignition oxidation zone tended to decrease on the side of the belt roadway and increase on the side of the track roadway.
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