聚合物驱油藏剩余油饱和度分布预测的φ函数法

用φ函数方法对水驱油藏剩余油饱和度分布进行了预测,考虑了聚合物驱油过程中聚合物的吸附和渗透率下降等特征以及聚合物溶液的黏度与浓度的变化关系,对相对渗透率曲线进行了修正,得到聚合物驱油藏的剩余油饱和度与累积注入孔隙体积倍数的关系。通过相继求解压力和饱和度场,避免了求解过程中解的不收敛和不稳定问题以及数值模拟中需多次通过迭代直接或间接解多元方程组的运算。矿场实际应用表明,预测结果准确可行。

φ-function method for estimating residual oil saturation distribution in polymer-drive reservoir

The φ-function method which is used in estimating residual oil saturation distribution in water-drive reservoir was applied to polymer-drive reservoir in consideration of the characteristics of polymer-displacing process, such as polymer adsorption and the permeability descending. The relationship between viscosity and concentration of polymer solution was analyzed. The relationship between the saturation of residual oil and the pore volume factor of accumulative injection fluid was achieved by modifying the relative permeability curve. Solving pressure and saturation can avoid the instability and complex calculation of multi-element equations. The application of this method in pilot test showed that the predicted results were relatively accurate. This method is feasible for predicting the distribution of residual oil.