煤层瓦斯抽采多物理场参数动态响应特征及其耦合规律  

Dynamic response characteristics and coupling law of multi physical field parameters in coal seam gas drainage

作　　者：彭守建[1,2] 贾立 许江[1,2] 陈捷仁 戴诗杰 陈月霞 PENG Shoujian;JIA Li;XU Jiang;CHEN Jieren;DAI Shijie;CHEN Yuexia(State Key Laboratory of Coal Mine Disaster Dynamics and Control,Chongqing University,Chongqing 400044,China;State and Local Joint Engineering Laboratory of Methane Drainage in Complex Coal Gas Seam,Chongqing University,Chongqing 400044,China;School of Emergency Technology and Management,North China lnstitute of Science and Technology,Langfang 065201,China)

机构地区：[1]重庆大学煤矿灾害动力学与控制国家重点实验室,重庆400044 [2]重庆大学复杂煤气层瓦斯抽采国家地方联合工程实验室,重庆400044 [3]华北科技学院应急技术与管理学院,河北廊坊065201

出　　处：《煤炭学报》2022年第3期1235-1243,共9页Journal of China Coal Society

基　　金：国家自然科学基金面上资助项目(52074047,51874055);重庆市研究生科研创新资助项目(CYB21025)。

摘　　要：为进一步深化煤矿瓦斯抽采过程中多物理场参数动态响应特征及其耦合作用机理的认识,运用自主研发的多场耦合瓦斯抽采物理模拟试验装置,开展了工作面前方不同应力区域瓦斯同步抽采物理模拟试验,分析了抽采过程中煤体温度场、瓦斯压力场和煤体变形场的实时演化特征及多物理场耦合作用机制。研究结果表明:①在同步抽采过程中,应力Ⅳ区煤体温度下降速率最快,其次为应力Ⅰ区和应力Ⅱ区,应力Ⅲ区的温度下降速度最慢,不同区域瓦斯压力衰减特征与煤体温度下降规律具有相似性。煤体变形受煤体温度和瓦斯压力的耦合作用影响,使煤体变形呈非线性增加。应力Ⅳ区煤体变形量最大,应力Ⅲ区由于受泊松效应影响,其煤体变形大于应力Ⅰ区和应力Ⅱ区。②在同步抽采过程中,各应力区域煤体变形具有阶段性变化特征,分为变形延迟阶段、变形启动阶段和变形二次递增阶段,变形延迟的实质是煤层中大量分布的微孔和小孔,对吸附态瓦斯脱附的束缚作用,加上煤基质对瓦斯的毛细凝结作用,导致瓦斯解吸滞后,从而出现煤体变形延迟现象。③各应力区域煤体变形的动态响应受到有效应力压缩效应、基质收缩效应、解吸热收缩效应和泊松效应等共同影响,泊松效应对应力Ⅲ区起主导作用,有效应力压缩效应是突破变形延迟现象的关键因素,解吸热收缩效应和基质收缩效应是煤体变形二次递增的主要原因。To further deepen the understanding of the dynamic response characteristics and coupling mechanism of multi field parameters during coal mine gas drainage,the self-developed multi field coupling gas drainage physical simulation test device was used to carry out the physical simulation test of gas synchronous drainage in different stress areas in front of the working face.The real-time evolution characteristics of coal temperature field,gas pressure field and coal deformation field and the coupling mechanism of multiple physical fields were analyzed.The results show that:①During the synchronous drainage,the decreasing rate of coal temperature in stress zoneⅣis the fastest,followed by those in stress zone I and stress zoneⅡ.the decreasing rate of temperature in stress zoneⅢis the slowest.The attenuation characteristics of gas pressure in different regions are similar to the law of coal temperature decline.The coal deformation is affected by the coupling effect of coal temperature and gas pressure,which makes the coal deformation increases nonlinearly.The coal deformation in stress zoneⅣis the largest,and the coal deformation in stress zoneⅢis greater than that in stress zone I and stress zoneⅡdue to the limitation of poisson effect.②During synchronous drainage,the coal deformation in each stress area has the characteristics of phased change which is divided into deformation delay stage,deformation start-up stage and deformation secondary increasing stage.The essence of deformation delay is the binding effect of a large number of micropores and pores in the coal seam on the desorption of adsorbed gas,coupled with the capillary condensation effect of coal matrix on gas,resulting in the lag of gas desorption,thus,the coal deformation is delayed.With the progress of drainage,the coal deformation delay is broken through,the deformation increases gradually,and the phenomenon of secondary increase appears.③The dynamic response of coal deformation in each stress region is affected by effective stress comp

关 键 词：瓦斯抽采 多物理场 煤体变形 响应特征 耦合机理 

分 类 号：TD712[矿业工程—矿井通风与安全]