Process-Dependent Solute Transport in Porous Media

Abstract Solute transport under single-phase flow conditions in porous micromodels was studied using high-resolution optical imaging. Experiments examined loading (injection of ink-water solution into a clear water-filled micromodel) and unloading water an filled micromodel). Statistically homogeneous fine-coarse patterns were used. It is shown that the time scale during larger than loading, even micromodel with structure, so values dispersion coefficient obtained for unloading. The difference between cases decreased increase rate. This implies diffusion key factor controlling degree scales, considered here. Moreover, patterned heterogeneity micromodel, containing distinct sections fine coarse media, increased scales processes. These results raise question whether this discrepancy same hydrodynamic observable at length scales.