Comparing Equations for Two-Phase Fluid Flow in Porous Media

T. Bjornara, and E. Aker
NGI, Oslo, Norway

Various types of equation system formulations for modeling two-phase flow in porous media using the finite element method have been investigated. These allow for equation manipulation such that the main differences between the formulations are the dependent variables that are solved for.

Here we have tested five different formulations for 2D simulations and one for 1D; the Buckley-Leverett equation. The various formulations are compared with regards to numerical performances like robustness (numerical stability) and solving time.

The tests performed strongly suggest that the fractional flow formulation is the fastest and most robust formulation.