钻孔钻进期间瓦斯涌出数值模拟  

Numerical simulation of gas emission during borehole drilling

作　　者：王钧 赵东 WANG Jun;ZHAO Dong(College of Safety and Emergency Management Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Key Laboratory of In-Situ Property-Improving Mining of Ministry of Education,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学安全与应急管理工程学院,山西太原030024 [2]太原理工大学原位改性采矿教育部重点实验室,山西太原030024

出　　处：《矿业安全与环保》2023年第6期77-84,共8页Mining Safety & Environmental Protection

基　　金：山西省回国留学人员科研项目(2022-052);山西省基础研究计划项目(自由探索类)(202303021211076)。

摘　　要：为了分析钻孔钻进瓦斯涌出规律,建立流—固耦合双孔介质模型,并模拟分析了瓦斯压力、孔径、基质解吸时间及Klinkenberg因子对钻孔钻进瓦斯涌出的影响。结果表明,不同位置孔壁暴露时间不同,压力降幅不等,瓦斯渗流速度不同;瓦斯流量呈现增长趋势,且增长速度不断减缓,使用单孔模型则会严重高估瓦斯流量。瓦斯压力是影响钻进瓦斯涌出的关键性因素;孔径增大促使瓦斯流量及涌出量增高;基质瓦斯解吸时间增大减少了对裂隙瓦斯的补充;Klinkenberg因子能够显著促进渗透率的增大进而提高渗流速度,增大瓦斯涌出量,但瓦斯涌出量存在一个极限值。In order to analyze gas emission during borehole drilling,a model of fluid-solid coupling dual-hole media was established,and the effects of gas pressure,borehole diameter,matrix desorption time and Klinkenberg factor on gas emission during borehole drilling were simulated and analyzed.The results show that the exposure time,pressure drop and gas seepage rate are different at different positions of hole wall.The gas flow shows a growing trend and the growth rate keeps slowing down,and using a single-hole model will seriously overestimate gas flow.The gas pressure is the key factor affecting gas emission in drilling;the increase of hole diameter promotes the increase of gas flow and emission;the increase of matrix gas desorption time reduces the gas replenishment to the fracture;Klinkenberg factor can significantly promote the increase of permeability,thereby increasing the seepage speed and increasing the amount of gas emission,but there is a limit value of gas emission.

关 键 词：煤层瓦斯 流—固耦合 数值模拟 钻孔钻进 顺层钻孔 双孔介质 

分 类 号：TD712.6[矿业工程—矿井通风与安全]