The displacement of fluid fronts and the movement of solute plumes across porous media interfaces with different material properties (physical or chemical) often involve complex interactions and may result in drastic changes in phase morphology and transport pathways that are difficult to predict with present continuum models. Examples of interfaces related to two-phase flow are displacement fronts emerging during infiltration or evaporation with complex shape and roughness inducing heterogeneities in liquid phase distribution within the porous systems. Examples of interfaces related to solute transport are dye patterns that express the heterogeneity of the underlying flow regimes.

The session solicits contributions on delineation of interfaces at scales ranging from the motion of single meniscus to the displacement of drying and infiltration fronts. Different model concepts to predict displacement fronts and solute concentration patterns, such as invasion percolation approaches or diffusion limited aggregation and comparisons with continuum approaches are particularly encouraged. We also invite experimental contributions documenting effects of textural contrasts on flow and transport at scales ranging from pore to plot scale (unstable and preferential flow), presentations on quantification and classification of complex flow patterns (mathematical morphology, information theory) and on numerical methods and model concepts to handle the sharp interfaces and to capture them in upscaled models.