基于工业CT扫描和LBM方法的含瓦斯煤裂隙演化与渗流特性研究  

Fracture evolution and permeability characteristics in gas-bearing coal based on industrial CT scanning and LBM method

作　　者：王登科[1,2,3,4] 田晓瑞 魏建平 张宏图[1,3] 姚邦华 付建华[5] 尚政杰[5] 吴岩 WANG Dengke;TIAN Xiaorui;WEI Jianping;ZHANG Hongtu;YAO Banghua;FU Jianhua;SHANG Zhengjie;WU Yan(State Key Laboratory Cultivation Base for Gas Geology and Gas Control,Henan Polytechnic University,Jiaozuo,Henan 454000,China;State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines,Anhui University of Science and Technology,Huainan,Anhui 232001,China;School of Safety Science and Engineering,Henan Polytechnic University,Jiaozuo,Henan 454000,China;State Collaborative Innovation Center of Coal Work Safety and Clean-efficiency Utilization,Jiaozuo,Henan 454000,China;Zhengzhou Coal Industry(Group)Corporation Limited Liability Company,Zhengzhou,Henan 450000,China)

机构地区：[1]河南理工大学河南省瓦斯地质与瓦斯治理重点实验室—省部共建国家重点实验室培育基地,河南焦作454000 [2]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 [3]河南理工大学安全科学与工程学院,河南焦作454000 [4]煤炭安全生产与清洁高效利用省部共建协同创新中心,河南焦作454000 [5]郑州煤炭工业(集团)有限责任公司,河南郑州450000

出　　处：《采矿与安全工程学报》2022年第2期387-395,共9页Journal of Mining & Safety Engineering

基　　金：国家自然科学基金项目(51774118,51974109);河南省高等学校重点科研项目计划基础研究项目(21zx004);河南省科技创新领军人才项目(204200510032);深部煤矿采动响应与灾害防控国家重点实验室开放基金项目(SKLMRDPC20KF06)。

摘　　要：煤层裂隙系统的扩展和发育是控制煤层渗透率的主要因素,分析加载条件下煤层渗透率的变化对研究煤层气的运移特性及其开发具有重要意义。开展了基于工业CT扫描条件下的含瓦斯煤三轴渗流实验,测试结果表明:含瓦斯煤在加载条件下的变形过程大致分为初始裂隙压密阶段、弹性变形阶段、屈服变形阶段、破坏阶段和残余变形阶段;基于CT扫描技术的裂隙重构真实客观反映了含瓦斯煤三维裂隙场的演化过程;含瓦斯煤渗透率大小与其内部裂隙发育和扩展密切相关,并随变形表现出了先减小后增加,再减小再增加的变化特征。采用格子Boltzmann方法模拟重现了含瓦斯煤全应力-应变过程中内部渗流场的演化规律,并预测了含瓦斯煤的渗透率,预测渗透率平均误差为11.11%。与含瓦斯煤内部裂隙发育程度及演化过程高度吻合,有效揭示了裂隙控制下的含瓦斯煤渗透性演化过程和特征。研究结果可为裂隙煤体瓦斯抽采和煤矿安全生产提供理论支撑。Expansion and development of coal seam fracture system is the main reason to control the permeability of coal seam.Analysis of change of coal seam permeability under loading condition is of great significance to study migration characteristics and development of coalbed methane.Triaxial seepage tests of gas-bearing coal under industrial CT scanning were carried out.The results have shown that deformation process of gas-bearing coal under loading condition can be divided into initial fracture compaction stage,elastic deformation stage,yield deformation stage,failure stage,and residual deformation stage.Fracture reconstruction based on CT scanning technology reflects evolution process of gas-bearing coal three-dimensional fissure field,and permeability of gas-bearing coal is closely related to the development and expansion of its internal fissure;during deformation,permeability shows the characteristics of decreasing and increasing,and decreasing and increasing.The evolution law of internal seepage field in the process of total stress-strain of gas-bearing coal was simulated and reproduced with lattice Boltzmann method and the permeability of gas-bearing coal was predicted.The average error of 11.11%in predicting permeability with lattice Boltzmann method was highly consistent with the degree of fracture development and evolution process of gas-bearing coal,which has effectively revealed the evolution process and characteristics of gas-bearing coal permeability under fracture control.The results can provide theoretical support for gas extraction and coal mine safety.

关 键 词：含瓦斯煤 格子BOLTZMANN方法 CT扫描 裂隙演化 瓦斯渗流 

分 类 号：TD713[矿业工程—矿井通风与安全]