利用高抽巷抽采工作面与断裂带卸压瓦斯是煤层群瓦斯治理的重要技术手段，为进一步提高高抽巷瓦斯抽采效果并实现精准抽采，基于砌体梁理论和“O”形圈理论建立采空区非线性渗透率模型，以此建立更符合实际情况的模拟模型，提高数值模拟结果的准确性，并将其运用到Fluent模拟软件中分析高抽巷在不同抽采负压、垂距、平距下对采空区瓦斯三维流场的影响规律，进而提出了高抽巷精准抽采的优化技术参数。结果表明，采空区渗透率分布特征规律为沿采空区倾向，进风、回风巷两侧渗透率大，阻力系数较小，中部渗透率较小，呈先减小后增大趋势分布；沿采空区走向方向，随着远离工作面，渗透率逐渐下降，在压实稳定区内基本保持稳定；采空区内瓦斯分布受风流及高抽巷抽采的影响，进风巷侧瓦斯浓度较低，回风巷侧瓦斯浓度较高，采空区瓦斯浓度分布等值线呈现“外凸”分布；当高抽巷平距为32 m，垂距为30 m，抽采负压为15 kPa时，抽采效果最佳，且采空区低浓度瓦斯分布范围较广，瓦斯浓度峰值最小，可以有效降低上隅角瓦斯浓度；通过对比现场实测高抽巷瓦斯抽采效果及上隅角瓦斯浓度和模拟结果，验证了模拟结果的准确性。研究结果可为高瓦斯煤层群精准开采及高抽巷参数优化提供理论依据。

High-drainage roadway extraction working face and fracture zone pressure relief gas is an important means for coal seam group gas control. In order to further improve the gas extraction effect of high-drainage roadway and achieve precise extraction,based on the masonry beam theory and the "O" ring theory,this paper establishes a non-linear permeability model of the gob,so as to establish a simulation model that is more in line with the actual situation and improve the accuracy of the numerical simulation results. And apply it to the fluent simulation software to simulate and analyze the influence of the high-drainage roadway on the three-dimensional gas flow field in the gob under different suction pressure,vertical distance and horizontal distance,and then propose the optimized technical parameters of high-drainage roadway precise drainage. The results show that along the gob trend,the permeability on both sides of the air inlet and return roadway is large,and the resistance coefficient is small. Along the gob,as the working face moves away,the permeability gradually decreases,and basically remains in the compaction stable area stable; Affected by wind current and high-drainage drainage,the gas concentration on the side of the air inlet roadway is low,while the gas concentration on the side of the return airway is relatively high. The gas concentration distribution contour in the gob shows an "outward convex" distribution; When the horizontal distance of the roadway is 32 m,the vertical distance is 30 m,and the suction pressure is 15 kPa,the high-drainage roadway has the best drainage effect,which can effectively reduce the upper corner gas concentration; the gas drainage effect of the high-drainage roadway is measured on site the gas concentration in the upper corner verifies the accuracy of the simulation results. The research results can provide a theoretical basis for the precise mining of high gas coal seams and the optimization of high-drainage roadway parameters.

0 引言

1 采空区非线性渗透率模型

2 采空区瓦斯流场模型构建

   2.1 工程背景

   2.2 物理模型

   2.3 渗透率模型

   2.4 边界条件

   2.5 模拟方案

3 数值模拟结果分析

   3.1 高抽巷抽采负压

   3.2 高抽巷垂直布置参数

   3.3 高抽巷水平布置参数

4 工程验证

5 结论