摘要
达西定律是描述储集层中流体流动特征的经典定律,但低速非达西流动现象及理论对达西定律在低流速下的适用性提出了质疑。吉木萨尔凹陷典型致密砂岩的孔隙形状多样,分布不均,呈现极细喉—中大孔组合方式。采用高效精准实验设备开展低速渗流实验,实验流体为矿化水和模拟油,采用高精度注射泵保证流体恒速流动。通过乘幂关系表征压力梯度—达西流速关系,对基于渗透率的阻力系数—雷诺数关系进行分析,来判断流体流动状态。结果表明,压力梯度—达西流速的乘幂关系和阻力系数—雷诺数关系的判断结果一致,在吉木萨尔凹陷致密砂岩储集层中,流体在低流速下均符合线性流动。此外,根据流量—压力梯度曲线分析,吉木萨尔凹陷致密砂岩储集层中单相流体在低流速下基本符合线性流动,且致密砂岩中单相流体的流动行为与岩石的性质有关,与流体类型无关。
Darcy’s law is a classic formula to describe fluid flow in reservoir rocks,but low⁃velocity non⁃Darcy flow phenomena and the re⁃lated theories raise questions about the applicability of Darcy’s law at low flow rates.The pores in the typical tight cores from Jimsar sag are various and unevenly distributed,showing a extremely fine throat-medium⁃large pore combination pattern.Low velocity flow experi⁃ments are carried out with high precision instruments,mineralized water and simulated oil,and a high accuracy syringe pump is used to en⁃sure the constant flow of fluids.The Darcy’s flow velocity-pressure gradient relationship is characterized by a power relationship,and the resistance coefficient-Reynolds number relationship based on permeability is analyzed to determine the fluid flow state.The experiment re⁃sults show that the pressure gradient is exponentially related to Darcy velocity,which is consistent with the analysis result of the relation⁃ship between Reynolds number and resistance coefficient.In the cores obtained from the tight reservoir in Jimsar sag,the low⁃velocity flow is linear flow.In addition,according to the analysis on the flux-pressure gradient curve,the low⁃velocity flow of single phase fluid in the core of the Jimsar tight sandstone reservoir basically accords with linear flow,and the flow behavior of the single⁃phase fluid in the tight sandstone is related to the property of the rock rather than fluid type.
作者
袁银春
李闽
王颖
李传亮
魏铭江
YUAN Yinchun;LI Min;WANG Ying;LI Chuanliang;WEI Mingjiang(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu,Sichuan 610500,China)
出处
《新疆石油地质》
CAS
CSCD
北大核心
2020年第3期349-354,共6页
Xinjiang Petroleum Geology
基金
国家科技重大专项(2016ZX05048-002)
国家973项目(2015CB250902)。