Popis: |
The nonlinear flow exists in ultra-low-permeability reservoir. It is important to establish an analytical model, which can be used in revealing nonlinear flow rule and improving producing status in field. According to the potential superposition principle, the mathematical model to predict the pressure gradient is established, and then, the nonlinear flow model is established by combining the pressure gradient boundary getting from the indoor nonlinear flow, and at last nonlinear flow area is determined in plane by increasing virtual production wells. It shows three features in the application of T14 block in Hailar oilfield. Firstly, the high value zone of cross-well pressure gradient is mainly concentrated in the area of 20–50 m near the oil–water well. Secondly, the pressure gradient is obviously affected by well spacing, and its lowest value is inclined to one side of the oil well. At last, the nonlinear flow zone is the main zone in ultra-low-permeability reservoir, and the area percentage is 60%, which is the main cause of the quickly production decline. The nonlinear flow area can be determined using the dynamic data. It can overcome two problems including parameter selection and extension in oilfield. |