页岩气藏压裂水平井线性耦合渗流模型研究  

Linear Coupling Seepage Model for Fractured Horizontal Wells in Shale Gas Reservoir

作　　者：张烈辉[1] 崔乾晨 谢军[2] 郑健 李成勇 ZHANG Liehui;CUI Qianchen;XIE Jun;ZHENG Jian;LI Chengyong(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu,Sichuan 610500,China;Southwest Oil and Gas Field Company,PetroChina,Chengdu,Sichuan 610051,China;Sichuan Changning Natural Gas Development Company Limited,Chengdu,Sichuan 610051,China;College of Energy,Chengdu University of Technology,Chengdu,Sichuan 610059,China)

机构地区：[1]油气藏地质及开发工程国家重点实验室·西南石油大学,四川 成都 610500 [2]中国石油西南油气田公司,四川 成都 610051 [3]四川长宁天然气开发有限责任公司,四川 成都 610051 [4]成都理工大学能源学院,四川 成都 610059

出　　处：《西南石油大学学报（自然科学版）》2019年第6期1-12,共12页Journal of Southwest Petroleum University(Science & Technology Edition)

基　　金：国家自然科学基金(51874251);四川省科技计划重点研发项目(2018JZ0079);中国石油天然气股份有限公司重大科技专项(2016E-0611)

摘　　要：为研究页岩基质孔隙中气体低速流动时启动压力梯度对试井的影响、解决页岩气复杂流动机理耦合的困难,提出了一种新的圆柱状三重孔隙页岩基质模型,并与五线性渗流模型结合,建立了表征气体流动过程的多级压裂水平井线性耦合渗流模型;应用Laplace变换、Green函数等方法得到模型的解,利用Stehfest数值反演算法计算并绘制了气井无因次拟压力响应曲线并进行敏感性分析。结果表明,基于新模型的压力响应曲线可划分为七个流动阶段;启动压力梯度主要影响曲线的中晚期阶段,若启动压力梯度越大,则渗流阻力越大、拟压力及其导数值越大;基质渗透率越小,则基质向裂缝系统窜流越困难、边界控制流动阶段发生时间越晚。In order to study the effects of threshold pressure gradient at low-velocity gas flow in shale matrix on well test curves,and to overcome the difficulties of coupling of flow mechanism of shale gas,a new cylindrical triple-porosity shale matrix model was proposed.Combined with the five-region flow model,a new linear seepage model characterizing flow process of multifractured horizontal wells was established.Laplace transformation and Green function were employed to solve the model,and the Stehfest numerical inversion algorithm was applied to plot dimensionless pseudo-pressure curves and conduct sensitivity analysis.The results show that pressure response curves of the new model could be divided into 7 periods and the threshold pressure gradient conspicuously affects the middle and later periods.The lager the threshold pressure gradient is,the larger seepage resistance is,and the higher pseudo-pressure and its derivative are.The smaller the matrix permeability is,the more difficult it is for transition flow from matrix to fractures,and the later the boundary control flow occurs.

关 键 词：页岩气 压裂水平井 页岩三重孔隙基质 启动压力梯度 压力响应 

分 类 号：TE319[石油与天然气工程—油气田开发工程]