稳定聚驱阶段相渗曲线动态反演方法及其应用

针对聚驱阶段相渗曲线计算较为困难的问题,基于生产动态数据,结合水驱特征曲线和两相渗流理论,利用聚驱阶段的理论含水率—采出程度曲线与实际曲线进行历史拟合,采用非线性优化计算方法确定出聚驱阶段的相对渗透率曲线关系式。计算结果表明:聚驱时水相相对渗透率曲线较水驱时明显降低,油相相对渗透率曲线较水驱有所上升,同时聚驱的残余油饱和度端点值较水驱有所降低。该方法需要参数少,计算方便快捷,历史拟合程度高,更能准确描述油田的油水运动规律。

DYNAMIC INVERTING METHOD FOR THE RELATIVE PERMEABILITY CURVES IN THE STABLE POLYMER FLOODING AND ITS APPLICATION

In the light of the problem of the calculation difficulty of the relative permeability curves in the polymer flooding stage,on the basis of the production dynamic data and integrating with the water driving characteristic curves and two-phase flow theory,the theoretical water cut-recovery curve (fw-R） was fitted to the actual fw-R curve and moreover with the help of the nonlinear optimization calculating method,the relative permeability curve relationships were determined at the polymer flooding stage.The calculation results show that when flooded by the polymer,comparing with the water flooding,the water relative permeability curve is obviously decreased,while the oil relative permeability curve is risen a bit,at the same time,the end-point values of the remained oil saturation are dropped more.The method is characterized by less parameter,rapid and convenient calculation and much high matching degree,so it can more accurately describe the oil and water performance laws of the oilfield.