Water Flooding Behavior of High Water-Cut Oilfield

When the oilfield enters the ultra-high water cut period,the straight line of the curve of the ratio of oil-water relative permeability Kro/Krw and the value of water saturation Sw under semi-log coordinate coordinates deflects downward and a second straight line appeared. Based on this,the two straight line method is introduced,that is,type A water drive curve was separated a straight line in the median-high water cut and the ultra-high water cut period,it can be applied to the oilfield development prediction and the dynamic analysis. It was found that the changes of index of producing fluid,index of absorbing water and the increased speed of water cut in the ultra-high water cut period are different due to different measures. It provides certain guidance for the development of ultra-high-water-cut reservoir.