水驱油田理论含水上升率预测新方法及其应用

含水上升率是水驱油田开发效果评价和指标预侧的关键参数。文中基于甲、乙、丙、丁4种水驱特征曲线，推导出了含水上升率与含水率的理论关系式，并结合相渗曲线关系式，确定了含水上升率表达式的系数。在渤海C日油田的实际应用结果表明：基于甲型水驱特征曲线的理论含水上升率在含水率为50%处达到最大值，特征曲线关于该点对称;基于乙、丙型水驱特征曲线的理论含水上升率曲线，随含水率升高始终呈下降态势;基于丁型水驱特征曲线的理论含水上升率曲线，以中高含水期为转折点，呈先升后降的变化态势。通过将理论曲线与C日油田实际数据进行对比，得出油田适用的水驱特征曲线为丙型水驱特征曲线。由此可见，可以利用含水上升规律进行水驱特征曲线的判别选取。

A new method to predict the water cut increasing rate in water flooding oilfield and its application

The water cut increasing rate is a key parameter fnr the development effect evaluation and index prediction of water flooding oilfield. Based on A, B, C, D four types of water drive era＇re, the theory relationship between the water cut increasing rate and the water cut rate is derived. The formula coeffieient is determined with relative permeability curves. The resuhs of application in the CB Oilfield shows that for Type A water drive curve, the maxinmm value of the water cut increasing rate appears at the time when the water cut rate is up to 50%, about which the water cut increasing rate curve is symmetrical. For Type B and C water drive curves, the water cut increasing rate curve declines all the time with the increase of water cut rate. For Type D water drive curve, the water cut increasing rate curve shows the tendency of ascending first and decreasing later, turning at medium and high water cut stage. Through eomparing the theory curve with the practical data of CB Oilfield, it can draw a conclusion that Type C water drive curve is more suitable. Thus, it＇s feasible for us to select the water drive curve according to the law of water cut increasing.