基于煤体渗透率各向异性的瓦斯抽采特性研究  

Study on Gas Drainage Characteristics Based on Permeability Anisotropy of Coal

作　　者：张伟[1,2] 郑春山 薛生 江丙友 王志根[3] 刘健 王永[4] ZHANG Wei;ZHENG Chunshan;XUE Sheng;JIANG Bingyou;WANG Zhigen;LIU Jian;WANG Yong(State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines,Anhui University of Science and Technology,Huainan 232001,China;School of Energy and Safety Engineering,Anhui University of Science and Technology,Huainan 232001,China;China Coal Xinji Energy Co.,Ltd.,Huainan 232001,China;National Engineering Research Center for Coal Mine Gas Control,Huainan 232001,China)

机构地区：[1]安徽理工大学深部煤矿采动响应与灾害防控国家重点实验室,安徽淮南232001 [2]安徽理工大学能源与安全学院,安徽淮南232001 [3]中煤新集能源股份有限公司,安徽淮南232001 [4]煤矿瓦斯治理国家工程研究中心,安徽淮南232001

出　　处：《煤矿安全》2020年第7期6-11,16,共7页Safety in Coal Mines

基　　金：国家重点研发计划资助项目(2018YFC0808000);国家自然科学基金青年科学基金资助项目(51904013);安徽省高校自然科学研究资助项目(KJ2019A0124)。

摘　　要：为了确定合理的有效抽采区域,首先建立了含瓦斯煤岩体的流-固耦合模型,然后建立几何模型,利用COMSOL Multiphysics软件进行数值解算,在考虑渗透率各向异性的基础上,研究钻孔周围不同位置的瓦斯压力变化规律。结果表明:考虑渗透率各向异性之后,瓦斯压力等值线图呈现出椭圆形状;渗透率各向异性会影响瓦斯在煤体中的运移,渗透率越低,瓦斯在煤层中运移越慢;达西速度与渗透率成正比,即渗透率增大,达西速度随之增大,渗透率各向异性使钻孔周围达西速度等值线呈椭圆分布,越靠近钻孔中心,达西速度越大,且随着时间的增加,达西速度最大值在减小;当钻孔周围瓦斯压力达到0.74 MPa时,受渗透率各向异性的影响其有效抽采区域呈现左右大、上下小的分布,瓦斯在渗透率小的地方难被抽采。To determine the effective drainage area,a fluid-solid coupling model of gas-bearing coal rock mass is established,and the geometric model is established using COMSOL Multiphysics software for numerical solution.On the basis of considering the permeability anisotropy,the variation law of gas pressure in different positions around the borehole is studied.The results show that the gas pressure contour map presents an elliptical shape after considering the permeability anisotropy.The permeability anisotropy affects the gas migration in coal.The lower the permeability is,the slower the gas moves in the coal seam.The Darcy velocity is proportional to the permeability,i.e.the Darcy velocity increases with the increase of permeability.The permeability anisotropy makes Darcy velocity contours around boreholes elliptically distributed.The closer to the center of the borehole is,the higher the speed of Darcy velocity is,and the maximum Darcy velocity decreases with the increase of time.When the gas pressure around the drilling hole reaches 0.74 MPa,the effective extraction area of the borehole shows the distribution of large left-right and small upper-lower under the influence of permeability anisotropy.The gas is difficult to be extracted in the place with low permeability.

关 键 词：有效抽采区域 耦合模型 渗透率各向异性 瓦斯压力 达西速度 瓦斯抽采 

分 类 号：TD712[矿业工程—矿井通风与安全]