Relating Capillary Pressure to Interfacial Areas - S70

Capillary pressures were calculated from the observed interfacial curvature of the wetting-nonwetting interface, and these correlated closely to externally measured values of applied pressure.

For each applied pressure, the system established mechanical equilibrium characterized by stationary interfaces, uniform curvatures across the model, and random surface normals. To study the relationships among capillary pressure and the interfacial areas, we compare the curvature-based capillary pressure with the differential change in interfacial areas per volume as a function of wetting-phase saturation. The differential pressure contributions calculated from the experimental measurements are found to be nearly independent of the measured capillary pressure.