The interaction of two fluid phases in fractured media

In fractured porous media, interactions between immiscible fluid phases within the fractures place a critical control on system behavior. A key component of the interactions is the geometry, or structure, of the respective phases. Over the past 10 years, process-based experiments have greatly increased our understanding of phase structure development within individual fractures. In the past 2 years, new calculational models that incorporate some of this understanding have further demonstrated the influence of phase structure on flow and transport within the phases, and inter-phase mass transport. These computational models can now be applied to consider the efficacy and parameterization of constitutive relations for a subset of two-phase situations. Full understanding of the morphology, connectivity, and temporal dynamics of phase structure in rough-walled fractures is yet to be developed, and is a promising area for further research.