一种改进的乙型水驱特征曲线研究及应用

Research and Application of an Improved Type-B Water-Flooding Characteristic Curve

针对特高含水开发阶段经典水驱特征曲线无法准确刻画水油比变化特征的问题,在重新改进油水相对渗透率表征形式的基础上,运用渗流力学理论和油藏工程方法推导了改进的乙型水驱特征公式,并给出了采出程度与水油比的变化关系式;采用最小二乘法和穷举法解决了多参数拟合困难的问题,实现了曲线的自动拟合。通过公开文献资料验证表明,新油水相对渗透率曲线表征方法更加准确,改进的乙型水驱曲线拟合精度更高,可较好地反映油田特高含水阶段水驱特征曲线的“上翘”特征,适用于特高含水阶段生产开发动态的预测。

The classic waterflooding characteristic curve is limited in the characterization of water-oil ratio in the extra-high water-cut development stage.Based on the re-improving of oil-water relative curve characterization form,the seepage mechanics and reservoir engineering methods were used to derive a improved type-B waterflooding characteristic curve,which also provides the relationship between recovery degree and water-oil ratio.The least square and exhaustive methods were adopted to treat multi-variable fitting and realize the automatic curve fitting.According to the verification with published literature,the new oil-water relative permeability curve shows a favorable characterization.The improved type-B waterflooding characteristic curve shows a more accurate fitting performance,which could well characterize the“upward”of waterflooding characteristic curve in the extra-high water-cut development stage and is applicable for the production performance forecast in the ultra-high water-cut development stage.