复杂条件下的低渗透油田生产特征

PRODUCTION FEATURES IN COMPLEX LOW-PERMEABILITY RESERVOIR

在考虑了启动压力、毛管力、重力等因素的情况下 ,推导了低渗透油田油水两相渗流时含水率和无因次采油、采液指数的数学模型 ,并分析了上述 3种因素在数学模型中的作用。结果表明 ,对于水湿油藏 ,毛管力和启动压力的存在使含水率和无因次采液指数增加 ,重力则使无因次采液指数降低 ,而对含水率的影响与地层倾角有关。 3种因素均对无因次采油指数无影响。在理论分析的基础上 ,对胜利油区大芦湖低渗透油田的含水率和无因次采油、采液指数进行了实例计算 。

In consideration of three factors such as starting pressure, capillary force and gravity, the mathematic models for water cut and dimensionless liquid production indexes of low permeability reservoir with water oil two phase flow were developed. The effects of three factors on the result of mathematical model were analyzed. The result indicates that starting pressure and capillary force can make the water cut and dimensionless liquid production index increase for water wet reservoir. The gravity can reduce the dimensionless productivity indexes, and its effect on water cut is related to formation obliquity. The three factors have no relation with the dimensionless oil productivity index. The water cut and dimensionless productivity indexes of Daluhu Reservoir in Shengli Oilfield were calculated with the mathematical models. The reliability of the theory analysis was proved with a calculation example.