Numerical modeling of multiphase flow in porous media considering micro- and nanoscale effects: A comprehensive review

Multiphase flow in porous media involves a variety of natural and industrial processes. However, the microscopic description of multiphase flow is challenging due to fluid-fluid and fluid-solid interactions combined with complex pore topology. Thus, a systematic review of multiphase flow from molecular to pore scale perspectives is necessary. This work summarizes recent progress in numerical modeling of multiphase flow from molecular scale, pore scale, and reservoir scale simulations considering micro- and nanoscale effects. The analysis focuses on immiscible and miscible flow associated with liquid and gas phases, highlighting the micro- and nanoscale effects on the flow characteristics. Molecular simulations capture nanoscale effects such as adsorption, diffusion, and slip behaviors. The variation of wettability, pressure, and fluid saturation leads to film, slug, and droplet flows in nanopores. Pore scale simulations explain complex flow behaviors in microporous and nanoporous media. Capillary number and wettability lead to different invasion morphologies. Adsorption and slip effects are non-negligible for fluid flow in nanoporous media. Furthermore, there are obvious differences in reservoir simulation results with and without considering micro- and nanoscale effects. Generally, this in-depth review is intended to provide a comprehensive description of the multiphase flows through multiscale simulation methods being developed and assist industrial processes.