考虑夹层影响的渗透率粗化新方法

非渗透性的夹层对流体的运动有重要的控制作用。传统的渗透率粗化方法难以有效刻画夹层对渗透率模型的影响,特别是倾斜夹层。针对传统渗透率粗化方法的不足,提出了一种新的考虑夹层影响的渗透率粗化方法。该方法通过分析每一个粗化网格对应的精细网格中夹层的分布情况,确定该粗化网格不同方向上的渗透率。如果粗化网格在某一个方向上全部被夹层遮挡即不存在连通的砂体穿过整个粗化网格,则将该方向上的渗透率赋值为0,否则通过几何平均等张量平均法计算该方向的渗透率。新设计的方法能够在渗透率粗化模型中有效地反映精细地质模型中的夹层信息,更加准确地刻画渗透率的分布特点,为油藏数值模拟提供了更加可靠的参数场。

A NEW UP-SCALING METHOD FOR THE PERMEABILITY CONSIDERING THE INFLUENCES OF THE INTERLAYERS

Impermeable interlayers have control action to the fluid flow.The traditional methods of the permeability up-scaling can't effectively describe and characterize the interlayers;influence on the permeability model,especially the inclined interlayers.Aiming at the shortages of the traditional methods of the permeability up-scaling,a new method considering the influences of the interlayers is proposed.By means of analyzing the distribution situation of the interlayers in the fine grid belonging to the individual up-scaling grid,the permeabilities in different directions of the up-scaling grids can be obtained.If the up-scaling grid is shielded at any direction by the interlayers,meaning that it does not have the connecting sands penetrating the up-scaling grid,the assigned value of the permeability at the direction is 0,or else through calculating the permeability at the direction by the geometric average or other tensor averaging algorithms.The new method can effectively respond the interlayer informations of the fine geological model in the permeability up-scaling model,and it can more accurately characterize the distribution features of the permeability,meanwhile it can supply a more reliable parameter field for the numerical simulation of the oil reservoirs.