Method for predicting the optimal shut-in duration by coupling fluid flow and geological stress

摘要

The invention discloses a method for predicting the optimal shut-in duration by coupling fluid flow and geological stress, comprising the following steps: determine basic parameters; obtain the fracture length, fracture width and reservoir stress distribution based on the basic parameters; calculate the oil saturation, pore pressure, and permeability and porosity after coupling change in different shut-in durations on the basis of the principle of fluid-solid coupling; take the oil saturation, pore pressure, and permeability and porosity obtained in Step 3 as initial parameters and calculate the production corresponding to different shut-in time on the basis of the productivity model; finally select the optimal shut-in time based on the principle of fastest cost recovery. The present invention can accurately predict the optimal shut-in duration after fracturing to improve the oil and gas recovery ratio in tight oil and gas reservoirs with difficulty in development and low recovery.