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

1) A method for modelling compressible fluid flows in a multilayer porous medium crossed by a network of fractures of given geometry and by a well, comprising the following stages:

• a) discretizing each fractured layer by a grid pattern comprising fracture grid cells that are centred on nodes either at the fracture intersections or at the fracture ends, each node being associated with a matrix block including all the points that are closer thereto than to neighbouring nodes,
• b) calculating the local flows between each fracture grid cell and the associated matrix volume in a pseudosteady state, the transmissivity value being obtained by considering a linear variation of the pressure as a function of the distance between any point of the block and the fracture grid cell,
• c) determining the direct flows between the fracture grid cells,
• d) determining the direct flows between the matrix volumes through the common edges of the grid cells,
• e) determining the direct flows between the fracture grid cells and the matrix grid cells on the one hand, and the volume of the well on the other hand, and
• f) simulating the response of the well for imposed flow rate variations by means of a diffusion equation that connects the interactions between the pressure and flow rate variations that can be observed in the well.