预测水驱油田含水率的麦克斯韦模型及应用

针对传统水驱油田含水率预测模型只能计算含水率与累积产液量、累积产油量,而无法计算含水率与时间之间的关系,同时,部分含水率预测模型未知参数较多,计算过程复杂等问题。根据水驱油田的含水率变化规律,并取极限含水率为1,将统计学中的麦克斯韦模型应用于含水率预测。新模型计算得到“一簇水驱曲线”,可预测不同类型油藏含水率随开发时间的变化,且新模型只有一个未知参数b,求解简单方便。根据油田实际生产数据,利用MATLAB软件编程,计算出最佳参数值b,得到大庆油田南二三开发区、平湖油气田M油藏和大庆油田萨北过渡带区块预测含水率随开发时间的新模型,且三个油田最后10年预测含水率值与实际值的绝对误差平均值分别为2.88%、8.41%和7.29%,该模型预测精度较高,具有一定的可靠性和实用性,能够对水驱油田开发的含水率进行预测,指导水驱油田的开发。

Maxwell model for water cut prediction in water drive oilfield and its application

Traditional water cut prediction model can only calculate water cut,cumulative liquid production and cumulative oil production,but can not calculate the relationship between water cut and time.At the same time,some water cut prediction models have many unknown parameters and the calculation process is complex.According to the change law of water cut in water drive oilfield and taking the limit water cut as 1,Maxwell model in statistics is used to predict water cut.A cluster of water drive curves is obtained by the new model,which can predict the change of water cut of different types of reservoirs with development time.Moreover,the new model has only one unknown parameter b,which is simple and convenient to solve.According to the actual production data of the oilfield.The best parameter value b is calculated,and a new model for predicting water cut with development time is obtained for the South No.2-3 development zone of Daqing oilfield,M reservoir of Pinghu oil and gas field and Sabei transition zone block of Daqing oilfield.The average absolute error between predicted water cut value and actual value in the last 10 years is 2.88%,8.41%and 7.29%,respectively.It has certain reliability and practicability,and can predict the water cut of water drive oilfield development and guide the development of water drive oilfield.