Method for modelling flows in a fractured medium crossed by large fractures

摘要

Method for modelling flows in a fractured medium crossed by a network of fluid conducting objects of definite geometry but not homogenizable on the scale of each grid cell of the model (large fractures, sub-seismic faults for example, very permeable sedimentary layers, etc.). ;The method allows to simulate fluid flows in a fractured porous geologic medium of known structure that is discretized with a grid and modelled by considering that each elementary volume of the fractured geologic medium consists of an equivalent fracture medium and matrix medium on the scale of each cell between which fluid exchanges are determined. The method comprises determining exchanges between the matrix medium and the fracture medium, and modelling the transmissivities of the various cells crossed by each conducting object, so that the resulting transmissivity corresponds to the direct transmissivity along this conducting object. Explicit modelling of these objects, which is prohibitive on the scale of a field because of the very large number of cells involved and of the numerical constraints, is therefore unnecessary.