油藏综合相渗曲线拟合方法

The methods to fit the curve of integrated relative permeability in reservoir

多孔介质中存在多相流体时,其相对渗透率会受到润湿性、岩石结构、流体饱和顺序等因素影响。岩心室内试验得到的单个样品相对渗透率变化规律仅表征了某种孔隙结构下的渗流规律,而储层孔隙结构的非均质性对渗流的影响很难用一块岩样试验结果表达清楚。表征油藏中多个含油小层、以及同一小层不同沉积相带孔隙结构储层油水渗流规律需要综合各样品的试验结果,不同样品在综合过程中所占比重也需要合理分配。利用室内相渗试验、岩心化验分析结果,提出油藏综合相渗曲线渗透率拟合目标值等于油藏的平均渗透率,样品在综合曲线中的权重系数根据孔隙结构分布规律或渗透率分布规律确定,并给出了拟合油藏综合相渗曲线具体方法及步骤。

When multiphase fluids are in porous media,their relative permeability would be affected by wettability,the rock tex ture,the order of fluid saturation and other factors.The variation rules of relative permeability for individual sample,obtained through core laboratory testing,only characterize the seepage law for certain pore structure,and it is difficult to use the test data of one rock specimen to express clearly the influence of heterogeneity of reservoir pore structure on seepage flow.The seepage law of reservoir pore structure in multiple oil-bearing layers and different sedimentary facies of one layer needs to integrate the test re sults of various samples,and different samples also need a reasonable allocation in the integrated process.By using the laboratory relative permeability tests and the results of core analysis,this paper concluded that fitting target value of integrated relative perme ability in reservoir equaled the average reservoir permeability and samples’weight coefficient in the permeability of integrated curve was based on pore structure distribution or permeability distribution.Finally,the concrete methods and steps to fit the curve of integrated relative permeability curve in reservoir were also provided.