检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
作 者:李伟[1,2] 杨世龙[1,2] 周红星 刘金兆[1,2] LI Wei;YANG Shilong;ZHOU Hongxing;LIU Jinzhao(National Engineering Research Center for Coal Mine Gas Control,China University of Mining and Technology,Xuzhou 221116,China;Faculty of Safety Engineering,China University of Mining and Technology,Xuzhou 221116,China)
机构地区:[1]中国矿业大学煤矿瓦斯治理国家工程研究中心,江苏徐州221116 [2]中国矿业大学安全工程学院,江苏徐州221116
出 处:《煤炭科学技术》2024年第4期193-202,共10页Coal Science and Technology
基 金:国家自然科学基金资助项目(52374243,51874295)。
摘 要:煤层渗透率作为衡量瓦斯渗流与抽采难易程度的重要指标,对其进行准确测定具有重要意义。针对现有方法计算渗透率测试周期长、结果不稳定、模型不完善等问题,研究煤层渗透率的快速准确测定方法及相应的计算模型。基于煤层中气体径向不稳定流控制方程,结合不同压差下气体在煤层中的体积流量方程,建立可利用全区间压降数据测定煤层渗透率的注气压降计算模型。应用COMSOL数值模拟软件的达西渗流模块对模型进行求解,针对现场工程设计中可对压降曲线产生影响的测压气室长度进行单变量处理,根据模拟结果分析钻孔的测压气室长度可设计为2.0 m。根据数值模拟结果进行现场布置,搭建井下重复注气压降试验系统,结合煤层瓦斯赋存条件和巷道条件施工两组穿层钻孔,对2个测点分别注入两次高于煤层瓦斯压力的补偿气体进行渗透率原位测试,测试周期分别约为6 d和17 d,第2轮测试的注气压力高于第1轮。结合理论推导验证了注气压降过程中煤层瓦斯的雷诺数均处于线性达西渗流段,瓦斯在煤层中的渗流符合达西定律,满足计算模型的假设。与传统煤层渗透率计算方法进行了比较,结果表明:本方法和径向流量法的计算结果基本一致,可以满足实际工程需要。重复注气压降法的测试结果稳定可靠,具备快速测定的优点。Permeability of coal seams is an important indicator for assessing the difficulty of gas seepage and extraction,and its accurate determination holds significant significance.In light of the existing issues with long testing cycles,unstable results,and imperfect models,this research focuses on developing a rapid and accurate method for determining coal seam permeability and the corresponding computational model.Based on the radial unsteady-state gas flow control equation within coal seams and the volume flow equation for gas under different pressure differentials within the coal seam,we have established an injection pressure drop calculation model that utilizes the entire pressure drop dataset for measuring coal seam permeability.The COMSOL numerical simulation software,equipped with the Darcy flow module,is employed to solve the model.To address variables affecting the pressure drop curve in field engineering design,a univariate analysis of the length of the pressure measuring gas chamber is conducted.According to simulation results,the gas chamber length for pressure measurement in boreholes can be designed as 2.0 meters.Field arrangements are made based on the numerical simulation results,and an underground repeated gas injection pressure drop test system is established.This system,in conjunction with coal seam gas occurrence conditions and tunnel conditions,facilitates the drilling of two cross-seam boreholes for each of the two test points.These boreholes are injected with compensatory gas twice,each time exceeding the coal seam gas pressure,to conduct in-situ permeability tests.The testing periods are approximately 6 days and 17 days for the first and second rounds,respectively,with the second round having higher injec-tion pressures.Combined with theoretical derivation,it was verified that the Reynolds numbers of coal seam gas remained within the linear Darcy flow regime during the gas injection pressure drop process,and gas flow within the coal seam adheres to Darcy's law,thus satisfying the assumptions of
关 键 词:重复注气压降法 煤层渗透率 注气参数优化 原位测试 瓦斯抽采
分 类 号:TD712[矿业工程—矿井通风与安全]
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:3.138.188.86