Water Flooding Development Law Research On The Second Type Tracts Of Chaoyanggou Oilfield

Based on the studying of Chaoyanggou OilField, and according to relative permeability data normalized methods, two types representative oil-water relative permeability curves were derived. The relationship of water cut, dimensionless liquid production index and productivity index was calculated through relative permeability, the change regulations of dimensionless liquid productivity index and oil productivity index were analysized, contrasted with the actual data of oilfield, dimensionless fluid productivity index calculation formula was amended. Considering the influence of formation degassing, calculation formula was amended to predict the actual fluid index changes of Chaoyanggou Oilfield. Based on relative permeability data, the relationship curve of recovery and water cut was calculated by applying theoretical formula, compared with the actual recovery curve, the change regulation between recovery and water cut was analysised. According to the numerical simulation results, the change regulation between water cut and recovery of each layer was analysised. Water flooding effects of the second type tracts of were evaluated, providing a basis for decision making for the oilfield development and adjustment. According to oil statistics to regress different types of water-drive law curves, combing with theoretical analysis, the main type of Chaoyanggou oilfield waterflooding law curve was first type, the formula for calculating the water production and water cut was derived. Considering the existing of startup pressure in low-permeability oilfield, the formulas for calculating the distribution of reservoir pressure and liquid production were derived. The liquid production change regulations of the second type tracts was analysized, the formula of limited liquid production capacity was given. At the basis of the above-mentioned study, water flooding development regulation of the second type tracts was further studied by applying numerical simulation. injection intensity impacting on liquid production capacity and limited production capacity were calculated by Eclipse. The results of numerical simulation method and analytic formula method were identical, indicating that the theoretical formulas given in this article have more credibility. At the same time, the influence of well shut-in to water flooding was studied, which indicated that well shut-in at high watercut stage had little influences, well shut-in at middle-low watercut stage had notable influences. The recovery in region controlled by shut-in wells decrease above 10 percents.