摘要
在达西定律的基础上，通过数学分析得出结论：各向异性储集层在各个方向的渗透率数值虽不相等，但存在某种相关性，三维和二维渗透率张量分别是三阶和二阶对称矩阵，因而模拟模型网格设计的关键是求解主渗透率的方向余弦，以主渗透率方向作为模型网格的坐标轴方向。对于二维模拟来说，可以由４口井（Ａ，Ｂ，Ｃ，Ｄ）组成的典型井组为基本单元，先根据地质研究确定ｘ方向的主渗透率（Ｋｘ），再求解Ａ井、Ｂ井连线与Ｋｘ方向的夹角（θ）和渗透率方向系数（ｍ），根据Ｋｘ、θ和ｍ即可求出Ａ井与Ｂ井、Ｃ井、Ｄ井连线方向的渗透率，得出该基本单元的主渗透率初值；求解出若干基本单元后，进行某种加权平均，可得到模拟层及整个模型的网格方向。以长庆气田北区陕８１井组４口生产井２个主力生产层为计算实例。该方法在今后的数值模拟研究中有一定借鉴意义。图２表１参２（陈志宏摘）
Mathematical analysis based on Darcy's law gives a conclusion: In an anisotropic reservoir formation, although the permeabilities along different directions are unequal, yet they have some correlations, that the 2 dimensional and 3 dimensional permeability tensors are second order and third order symmetric matrices respectively. Therefore the key to simulation grid design is to solve the cosine of the direction of major permeability, taking the direction of major permeability as the direction of axis of the grid coordinate for the model. For a 2 dimensional model, a basic unit is formed by 4 wells (A, B, C, D), direction of x axis is determined by the direction of major permeability ( K x) through a geological study and then the angle between AB and direction of K x ( θ ), and direction coefficient ( m ) are determined; with known K x, θ and m , the permeabilities along AB, AC, and AD can be solved to find out the initial value of the major permeability of this basic unit. After the solution of several such units, certain weighed average technique should be taken to obtain the grid direction for the whole simulated layer and the whole model. With 4 wells and 2 production zones in Shan 81 well group in northern Changqing gas field as an example, this method has a certain reference value in the numerical simulation study. Subject
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
1999年第1期58-60,共3页
Petroleum Exploration and Development
关键词
储集层
数值模拟
网络方向
油层
渗透率
Darcy's law, Numerical simulation, Permeability anisotropy, Grid design
