文摘
The formation and development of patterns in the unstable interface between an injected fluid and hydrocarbons or saline aqueous phase in a porous medium can be driven by viscous effects and gravity. Numerical simulation of the so-called fingering is a challenge, which requires rigorous representation of the fluid flow and thermodynamics as well as highresolution discretization in order to minimize numerical artifacts. To achieve such a high resolution, we present higherorder 3D finite element methods for the simulation of fully compositional, three-phase and multi-component flow. This is based on a combination of the mixed hybrid finite element (MHFE) method for total fluid velocity and discontinuous Galerkin (DG) method for the species transport. The phase behavior is described by cubic or cubic-plus-association (CPA) equations of state. We present challenging numerical examples of compositionally triggered fingering at both the core and the large scale. Four additional test cases illustrate the robustness and efficiency of the proposed methods, which demonstrate their power for problems of this complexity. Results reveal three orders of magnitude improvement in CPU time in our method compared with the lowest-order finite difference method for some of the examples. Comparison between 3D and 2D results highlights the significance of dimensionality in the flow simulation. Keywords Gravitational fingering Mixed hybrid finite element methods Multiphase and multicomponent flow 3D simulation Compositional modeling