Increasing Oil Prediction Model for Weak Gel Flooding in the Transition Zone of Bohai Heavy Oil Reservoir

To solve the problems of less application examples and more difficult increasing oil prediction for weak gel flooding in offshore heavy oil (> 350 mPa·s), an oil production potential prediction model was established using numerical simulation methods and multiple regression method based on the weak gel flooding practice of the BN oilfield. This model can reflect the relationship between the oil increase and the eight static parameters and a uniform design sample set was established by the Latin hypercube experimental method. Finally, the prediction model can be used in transition zones of similar heavy oil reservoirs. The parameters of reservoir range are (1 000~9 000)×10^-3 μm² of average permeability, 0.1~0.9 of variation system, 1~20 of side water multiple, 100~500 m of injection and production well spacing, 0.2~1.0 of net gross ratio, 200~1 000 mPa·s of formation crude oil viscosity, 4~20 m of layer thickness, 0~200 m of the distance between well and oil outside boundary. The model predicts that the relative average error between the oil increase and the actual production is 2.5%, which meets the engineering application accuracy requirements.