A General Multiscale Hybrid Method for Transport through Complex Porous Media

Abstract:

Porous media flow and transport in the subsurface can be described over a hierarchy of scales ranging from atomistic to continuum. Depending on the physics of the problem we ought to incorporate all relevant scales. Often the behavior of the system is controlled by the phenomena at the pore-scale. Therefore accurate and efficient modeling of any large domain requires simulating parts of it at the pore-scale (i.e., wherein continuum models become invalid) and the rest at the continuum scale. Hybrid models combine pore-scale and continuum-scale representations. Desirable features of hybrid models are: 1) their ability to track where and when to use pore-scale models, i.e. their adaptability to time- and space-dependent phenomena, 2) their flexibility in implementing coupling boundary conditions, and 3) significant computational speed-up when the sub-domain wherein pore-scale simulations are required is much smaller than the total computational domain. Moreover, coupling conditions should be physics-based in order reduce the overall number of assumptions. We propose a general, robust and non-overlapping hybrid scheme based on IBM to model flow and reactive transport in porous media. The suggested algorithm has been numerically tested for several transport and flow scenarios.