关键词: 弹塑性, 储层, 流固耦合, 数学模型, 数值模拟, 有限元方法

Abstract: A numerical model, based on the finite element method, is established to describe a fluid flow in a deforming saturated oil reservoir.The mathematical formulation describes a fully coupled governing equation system which consists of the equilibrium of rock skeleton and continuity for a fluid flow in a porous medium.An elasto-plastic model is utilized on a basis of Mohr-Coulomb yield surface.The Galerkin finite element method is applied to obtain simultaneous solutions in the space domain to the governing equations where the displacements and the fluid pressures are the primary unknowns.The final discretized equations are sovled in the time domain by using a fully implicit numerical scheme and the fully coupled finite element equations are obtained.A linear analysis is used to study the stability conditions of the present model.This model has a wide range of applications in the field of oil reservoir engineering and provides a theoretical basis for numerial simulation of a fluid flow in a deforming saturated oil reservoir.

Key words: elasto-plastic, oil reservoir, fluid-solid coupling, mathematical model, numerical simulation, finite element method