【摘要】 根据格子玻尔兹曼(LBM)计算技术以及相应渗流理论,对顺层抽放条件下,裂隙煤体内瓦斯流动这一渗流问题进行了数值模拟研究,并对瓦斯压力在空间上的分布规律进行了深入的研究。以流场内瓦斯压力分布及瓦斯平均压力作为评价抽放效率的依据。结果表明,瓦斯压力分布、抽放效率与抽放孔长度、抽放孔间距、抽放负压、抽放时间步长有关。而且,抽放孔长度、抽放孔间距对瓦斯压力的分布影响较大,这与已有的理论分析和实测的结果相吻合。在预抽工作面进行了工业试验,通过改变抽放负压,检验了实际的抽放效果。研究结果表明LBM方法可为抽放条件下瓦斯在煤层中的运移规律提供新的研究途径,对瓦斯抽放有较大的指导意义。更多还原

【Abstract】 According to the Lattice Boltzmann Method computing technique and the corresponding percolation theory,the percolation problem of gas flow inside fractured coal body under the condition of gas drainage along bedding was simulated,and the gas pressure distribution in space was further researched as well.Pressure distribution and average pressure in the gas flow were seen as the basis for evaluation of drainage efficiency.The results showed that the gas pressure distribution and drainage efficiency were connected with drainage hole length,drainage hole spacing,negative pressure of drainage and drainage time step.Besides,drainage hole length and spacing influenced the gas pressure distribution comparatively serious,which tallied with the existing theoretical analysis and experimental results.Industrial experiment was carried out in the pre-drainage workface.In this experiment,the actual efficiency was tested by changing the negative pressure of drainage.The results indicated that the LBM technique would provide a new approach of researching the gas flow rules in coal seam under the condition of gas drainage,which have a greater significance to gas drainage.更多还原