Method for modelling fluid flows in a multilayer porous medium crossed by an unevenly distributed fracture network

摘要

A method is disclosed for modelling low or high compressibility fluid flows in a multilayer porous medium crossed by a network of fractures of given geometry, unevenly distributed in the medium, some of the fractures communicating with one another. Each fractured layer is defined by means of a grid pattern comprising fracture grid cells centered on nodes either at the fracture intersections or at the fracture ends. Each node is associated with a matrix block including all the points closer thereto than to neighboring nodes, and the local flows between each fracture grid cell and the associated matrix volume are calculated in a pseudosteady state. A modelling equation whose form is similar to the diffusion equation solved in conventional cases (low compressibility fluids) allows accounting for the compressibility of the fluids. The direct flows between the fracture grid cells and the direct flows between the matrix volumes through the common edges of the grid cells are determined, and the interactions between the pressure and flow rate variations that can be observed in at least one well through the medium are simulated.