CAJ | 학술논문

针对页岩气藏的特点，分析国内外对解吸、扩散等数学描述方法，建立三种机理作用下的渗流数学模型：①考虑有机基质表面解吸，解吸气和游离气共同窜流的数学模型；②考虑有机基质解吸和扩散的数学模型；③考虑有机基质中的气体解吸、扩散，以及无机基质中气体窜流综合作用的数学模型。运用点源函数方法，得到模型的基本点源解，对点源解作积分变换得到垂直压裂井、压裂水平井两种开采方式下的地层压力解，绘制出三种机理影响下的压力动态曲线，并从渗流机理上分析曲线特征以及不同曲线存在差异的原因。
침대혈암기장적특점，분석국내외대해흡、확산등수학묘술방법，건립삼충궤리작용하적삼류수학모형：①고필유궤기질표면해흡，해흡기화유리기공동찬류적수학모형；②고필유궤기질해흡화확산적수학모형；③고필유궤기질중적기체해흡、확산，이급무궤기질중기체찬류종합작용적수학모형。운용점원함수방법，득도모형적기본점원해，대점원해작적분변환득도수직압렬정、압렬수평정량충개채방식하적지층압력해，회제출삼충궤리영향하적압력동태곡선，병종삼류궤리상분석곡선특정이급불동곡선존재차이적원인。
According to characteristic of shale gas reservoir, mathematical description methods of diffusion and desorption are analyzed. Three seepage models controlled by different kinds of seepage mechanisms are built: ① a mathematical model which considers diffusion and interporosity of desorbed gas and free gas,② a mathematical model which considers desorption and diffusion,③ a mathematical model which considers desorption and diffusion in organic porosity and interporosity in inorganic porosity. With modified Lord Kelvin point source function pressure solutions are botained. With corresponding transformation for point source functions, formation pressure solutions for vertical fractured well and fractured horizontal well are obtained and typical curves are shown. At last, characteristics of different curves and three mechanisms’ influences on pressure are analyzed.