Pore-scale study of water salinity effect on thin-film stability for a moving oil droplet.

Hypotheses: The interfacial dynamics in natural porous media are affected not only by the interplay between viscous and capillary forces but also the solid surface wettability. It has been hypothesized that the wettability alteration induced by changes in the water salinity is primarily caused by electric double-layer force expansion, which strongly affects the multiphase flow dynamics.

Simulations: We investigate the effect of water ionic composition and surface roughness on pore-scale wettability alteration.

Measurements and simulation of liquid films during drainage displacements and snap-off in constricted capillary tubes.

When a wetting liquid is displaced by air in a capillary tube, a wetting film develops between the tube wall and the air that is responsible for the snap-off mechanism of the gas phase. By dissolving a dye in the wetting phase it is possible to relate a measure of the absorbance in the capillary to the thickness of liquid films. These data could be used to compare with cutting edge numerical simulations of the dynamics of snap-off for which experimental and numerical data are lacking.