页岩气藏流固耦合数学模型  

Mathematical model of fluid solid coupling in shale gas exploitation

作　　者：杨仙[1] 肖拥军[1] 黄俨然[1] 

机构地区：[1]湖南科技大学页岩气资源利用湖南省重点实验室土木工程学院,湖南湘潭411201

出　　处：《湖南科技大学学报（自然科学版）》2015年第3期52-56,共5页Journal of Hunan University of Science And Technology：Natural Science Edition

基　　金：湖南省教育厅科学研究一般项目(13c309);页岩气资源利用湖南省重点实验室开放基金资助项目(E21428);湖南省自然科学基金资助项目(14JJ6032)

摘　　要：页岩层是超低渗透率的储气层,页岩气藏开采过程中流固耦合效应表现明显.基于渗流力学和Biot固结理论,综合考虑页岩气藏储层的启动压力梯度,页岩气渗流过程中的解吸附,建立了一个适用于滑脱流、孔内扩散等页岩基质孔隙内所有气体流态形式的流固耦合数学模型.页岩气开采流固耦合数学模型包含了气体渗流和页岩变形相互作用的耦合项,必须进行耦合求解.使用显式迭代编制相应程序求解其数值解,计算结果表明,考虑流固耦合和不考虑流固耦合对页岩气开采过程中压力分布影响较大,考虑流固耦合情况下,压力降低趋势比不考虑耦合情况下要快,更符合实际开采情况.流固耦合现象对页岩气渗流过程影响较大,页岩气开采过程中必须考虑流固耦合影响.As a kind of low permeability reservoir,fluid solid coupling effect is obvious in shale gas reservoir exploitation. Based on seepage flow mechanics and Biot consolidation theory,considering the starting pressure gradient of shale gas reservoir,and desorption of shale gas,a coupling mathematical model was established,which was suitable to all gas flow type（ continuous flow,slip flow,transition flow,molecular collision） in shale pore. The mathematical model including the interaction of shale gas seepage and deformation,and must be solved by coupling. The numerical solution was gotten by program composition based on explicit iteration. The calculation results showed that the impact on pressure is obvious considering and not considering fluid solid coupling,pressure decreasing trend in fluid solid coupling is faster than that without considering coupling case,which fit reality more. Fluid solid coupling phenomenon,effect shale gas seepage greatly,must be considered in shale gas exploitation.

关 键 词：页岩气 流固耦合 启动压力梯度 解吸附 渗流 

分 类 号：TE31[石油与天然气工程—油气田开发工程]