抽采钻孔蠕变规律数值模拟研究  

Numerical Simulation Study on Creep Law of Gas Extraction Borehole

作　　者：韩颖[1,2,3,4] 闫志佳 牛琛 HAN Ying;YAN Zhijia;NIU Chen(School of Energy Science and Engineering,Henan Polytechnic University,Jiaozuo,Henan 454003,China;Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic Region(Henan Province),Jiaozuo,Henan 454003,China;Technology Platform of Deep Mine Strata Control and Methane Drainage for State Administration of Work Safety,Jiaozuo,Henan 454003,China;State Key Laboratory Cultivation Base for Gas Geology and Gas Control(Henan Polytechnic University)Ministry Co-construction State Key Laboratory,Jiaozuo,Henan 454003,China;College of Safety Science and Engineering,Henan Polytechnic University,Jiaozuo,Henan 454003,China)

机构地区：[1]河南理工大学能源科学与工程学院,河南焦作市454003 [2]中原经济区煤层(页岩)气河南省协同创新中心,河南焦作市454003 [3]深井岩层控制与瓦斯抽采国家安监局科技支撑平台,河南焦作市454003 [4]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,河南焦作市454003 [5]河南理工大学安全科学与工程学院,河南焦作市454003

出　　处：《矿业研究与开发》2024年第7期204-212,共9页Mining Research and Development

基　　金：国家自然科学基金资助项目(51974108,51404093);河南省自然科学基金项目(232300420077);河南省科技攻关项目(242102320213);河南省高校基本科研业务费专项资金资助项目(NSFRF240638);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开放基金项目(WS2020B12,WS2012A09);河南省博士后科研项目(001701014);河南理工大学博士基金资助项目(B2008-15,B2012-093)。

摘　　要：为了探讨抽采钻孔蠕变对成孔质量的影响,采用数值模拟软件COMSOL,建立了考虑蠕变的含瓦斯煤流固耦合模型,研究了孔周煤体应力-应变变化规律,同时,以某煤矿为例,模拟计算了泊松比为0.2~0.34,杨氏模量为2E8~4E8条件下瓦斯压力和位移变化,得到了泊松比和杨氏模量对孔周瓦斯压力及钻孔蠕变的影响规律。研究表明:随着泊松比和杨氏模量的增大,瓦斯压力梯度的变化减小,这对于煤层内瓦斯的抽采更有利;随着距钻孔的水平距离的增大,位移先降低再升高,但整体呈降低趋势;孔壁的位移随泊松比的增大而增大,随杨氏模量的增大而减小,随时间的推移逐渐趋于稳定;泊松比和杨氏模量越小,即煤岩越软,钻孔等效蠕变应变越明显;杨氏模量对钻孔蠕变的影响较泊松比更大。In order to study the influence of gas extraction borehole creep on borehole quality,a numerical simulation software COMSOL was used to establish a fluid-solid coupling model of gas containing coal considering creep.The stress-strain variation law of the coal body around the borehole was studied.At the same time,taking a coal mine as an example,the gas pressure and displacement changes were simulated and calculated under the conditions of Poisson's ratio of o.2-0.34 and Young's modulus of 2E8-4E8.The influence of Poisson's ratio and Young's modulus on the gas pressure around the borehole and the creep of the borehole were obtained.Research has shown that as the Poisson's ratio and Young's modulus increase,the change in gas pressure gradient decreases,which is more favorable for gas extraction in coal seams.As the horizontal distance from the borehole increases,the displacement first decreases and then increases,but overall shows a decreasing trend.The displacement of the hole wall increases with the increase of Poisson's ratio,decreases with the increase of Young's modulus,and gradually stabilizes over time.The smaller the Poisson's ratio and Young's modulus,the softer the coal rock,and the more obvious the equivalent creep strain of the borehole.The influence of Young's modulus on borehole creep is greater than that of Poisson's ratio.

关 键 词：钻孔蠕变 瓦斯抽采 流固耦合 泊松比 杨氏模量 

分 类 号：TD712[矿业工程—矿井通风与安全]