Numerical study on two-phase flow through fractured porous media

Based on the flux equivalent principle of a single fracture, the discrete fracture concept was developed, in which the macroscopic fractures are explicitly described as (n−1) dimensional geometry element. On the fundamental of this simplification, the discrete-fractured model was developed which is suitable for all types of fractured porous media. The principle of discrete-fractured model was introduced in detail, and the general mathematical model was expressed subsequently. The fully coupling discrete-fractured mathematical model was implemented using Galerkin finite element method. The validity and accuracy of the model were shown through the Buckley-Leverett problem in a single fracture. Then the discrete-fractured model was applied to the two different type fractured porous media. The effect of fractures on the water flooding in fractured reservoirs was investigated. The numerical results showed that the fractures made the porous media more heterogeneous and anisotropic, and that the orientation, size, type of fracture and the connectivity of fractures network have important impacts on the two-phase flow.