多因素耦合条件下煤层井壁稳定性分析模型研究  

Research on Analytical Model for Coal Bed Wellbore Stability with Multi-factors Coupling

作　　者：陈子剑[1] 刘伟[1] 邓金根[1] 蔚宝华[1] 田中兰 杨恒林 刘军波[3] 

机构地区：[1]中国石油大学(北京)石油工程学院,北京102249 [2]中国石油集团钻井工程技术研究院,北京102206 [3]中海油田服务股份有限公司钻井事业部,河北三河065201

出　　处：《煤炭技术》2016年第2期66-69,共4页Coal Technology

基　　金：国家科技重大专项(2016ZX05009-004-001);国家自然科学基金(U1262201)

摘　　要：针对煤岩的力学与渗流特性,综合考虑煤岩受力变形、损伤破坏与钻井液滤液侵入等多因素耦合条件,建立基于应力-渗流耦合的煤层井壁稳定性数值分析模型,采用弹性-应变软化-塑性模型表征煤岩的力学行为,更加准确地计算井周煤岩损伤破坏区域的尺寸与形状。研究结果表明,在井壁封堵良好的条件下,提高泥浆密度有利于稳定井壁,反之将加剧煤层井壁坍塌失稳。For the coal mechanical and seepage characteristics, with the consideration of multi-factors coupling, including the deformation, the damage-failure and the drilling fluid filtrate invasion, the coal bed wellbore stability numerical model which based on the coupling of stress and seepage is built. The coal mechanical behavior is expressed by the elastic-strain softening-plastic model, so as to calculate the size and shape of the damage-failure area around the coal wellbore more accurately. The results show that if the wellbore plugging property is good enough, the increase of drilling fluid density could improve the wellbore stability, otherwise, it would aggravate the wellbore instability.

关 键 词：煤层气 井壁稳定性 渗流 损伤 

分 类 号：TD32[矿业工程—矿井建设]