The present work concerns the development of a comprehensive model capability in ANSYS CFD software FLUENT towards modeling of multiphase flows in porous media with targeted applications in reservoir/well analyses. The modeling approach is based on the Eulerian multifluid model. Porous media are modeled by both Superficial and Physical Velocity formulation with embedded sub-models to account for the resistance sink, relative-permeability and capillary pressure effect. An advanced numerical algorithm has been developed to achieve time-step and mesh independent solutions as well as to satisfy the physical constraints/limits. In particular, the resistance sinks are rearranged and linearized to ensure numerical stability and to handle mathematically infinite resistance caused by possible zero relative permeability. The capillary pressure and body forces are implicitly treated to enhance solver robustness. The multiphase porous medium model is compatible with all the numerical schemes and solvers (iterative and non-iterative) available in FLUENT. The present model has been applied to simulate 1D, 2D and 3D transient oil-water two-phase flows mimicking the conditions in reservoirs and wells. The solutions are time-step and grid independent, and successfully reproduce the flow characteristics and physical limits. The solvers are fast and robust, allowing the time step to be as large as 2 hours for a reservoir setting with the flow physical time in 2–20 years. The model capability shows great promises for reservoir and well performance analysis.

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