CAJ | 학술논문

研究表明，页岩气藏孔隙尺寸主要分布在2~20 nm之间，经典的达西定律已不能准确地描述气体在纳米孔隙中的运移行为。为此，基于表观渗透率的定义，考虑了页岩气藏在生产过程中吸附层及粘度变化的影响，建立了粘性流、滑脱流、过渡流及Knudsen扩散4种运移模式综合作用下的数学模型。模型研究结果表明，表观渗透率远大于达西渗透率，而且孔隙半径越小、压力越低，表观渗透率与达西定律的比值越大，滑脱流、过渡流及Knudsen扩散产生的流量所占的比例越大；温度的影响作用较小，可以忽略；孔隙越小，吸附层变化的影响作用越大，压力越小，粘度变化的影响作用越大。
연구표명，혈암기장공극척촌주요분포재2~20 nm지간，경전적체서정률이불능준학지묘술기체재납미공극중적운이행위。위차，기우표관삼투솔적정의，고필료혈암기장재생산과정중흡부층급점도변화적영향，건립료점성류、활탈류、과도류급Knudsen확산4충운이모식종합작용하적수학모형。모형연구결과표명，표관삼투솔원대우체서삼투솔，이차공극반경월소、압력월저，표관삼투솔여체서정률적비치월대，활탈류、과도류급Knudsen확산산생적류량소점적비례월대；온도적영향작용교소，가이홀략；공극월소，흡부층변화적영향작용월대，압력월소，점도변화적영향작용월대。
Studies indicated that the pore radius of shale gas reservoir mainly concentrates from two nm to twenty nm,and the classic Darcy percolation law cannot fully describe the gas transport behavior accurately in nano pores. Therefore,based on the definition of the apparent permeability,taking the variation of absorbed layer and viscosity in the process of practical production into account,a mathematical model under the comprehensive function of four transport patterns is established,which are viscous flow,slip flow,transitional flow and Knudsen diffusion. The results show that the apparent permeability is much larger than Darcy permeability. The smaller the pore is ,and the lower the pressure is,the greater the ratio of the apparent permeability to Darcy permeability would be,and the larger the flow rate caused by slip flow,transitional flow and Knudsen diffusion would be. The influence of temperature is too small and can be ignored. The smaller the pore is,the greater the effect of absorbed layer variation would be,and the lower the pressure is,the greater the effect of viscosity variation would be.