Yang Ying, Zhang Xin, Zhou Xiaofeng, Wang Anlun, Li Jiangtao
Key Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development (Northeast Petroleum University), Ministry of Education, Northeast Petroleum University, Daqing 163318, Heilongjiang, China.
Institute of Unconventional Oil & Gas, Northeast Petroleum University, Daqing 163318, China.
ACS Omega. 2023 May 1;8(19):17077-17085. doi: 10.1021/acsomega.3c01391. eCollection 2023 May 16.
Shale gas reservoirs are rich in microscale fractures. In this paper, the characteristics of gas percolation in microscale fractures are taken as the research object. By coupling the actual gas equation, the multi-component gas equation, and the bulk gas diffusion equation, analytical solutions of the comprehensive percolation equation are obtained. Through mathematical model research, the following conclusions are obtained: (a) after considering the slip flow of the solid surface, the mass flow rate of multi-component gas under different pressure conditions increases by about 20-10,000%. (b) Different from continuous flow and slip flow, the mass flow rate of bulk gas diffusion decreases with pressure increase. (c) The intersection pressure is 31 MPa. When the pressure increases from 0.5 MPa to the pressure at the intersection point, the mass flow rate of integrated flow increases with decrease of the methane content. (d) When the pressure continues to increase from the intersection point pressure, the mass flow rate of integrated flow decreases with decrease of the methane content.
页岩气储层富含微尺度裂缝。本文以微尺度裂缝中气体渗流特征为研究对象。通过耦合实际气体方程、多组分气体方程和体相气体扩散方程，得到了综合渗流方程的解析解。通过数学模型研究，得出以下结论：(a)考虑固体表面的滑移流后，不同压力条件下多组分气体的质量流率增加约20% - 10000%。(b)与连续流和滑移流不同，体相气体扩散的质量流率随压力增加而降低。(c)交点压力为31MPa。当压力从0.5MPa增加到交点处压力时，综合流的质量流率随甲烷含量的降低而增加。(d)当压力从交点压力继续增加时，综合流的质量流率随甲烷含量的降低而降低。
