Random walk hydraulic modelling of fractured petroleum reservoirs

摘要

A method of determining, from a 3D image, the values of hydraulic parameters such as large-scale equivalent permeability, the permeability of blocks and the exchange coefficient alpha between matrix and cracks of a porous fractured medium such as a geological formation. The method essentially consists in breaking down the medium by means of a grid and rapidly and approximately solving in this medium equations which model the diffusion of fluids in the medium, determining the variation over time of a large-scale transfer function (f(t), f(s)) characterising the flows of fluid from the matrix to the cracks by simulating the movement of particles following continuous-time random walks on said grid and appropriately processing a function of state (#(#)) indicative of their presence either in the matrix or in a crack. Application to large-scale modelling of fractured petroleum reservoirs, enabling the interpretation of well tests, is also described.