The influence of contact angle on capillary pressure-saturation relations in a porous medium including various liquids

Quantitative description and modeling of two-phase flow in porous media requires specification of functional relationships between capillary pressure and saturation. In the presented study, this relationship was examined for various liquids by using the dimensionless capillary pressure function, which was developed by Leverett. The measurement of liquid saturations was achieved by a gamma attenuation system. The Ottawa sand as a homogeneous porous medium and water, ethanol, LNAPL (toluene) as liquids were used in the experiments. The imbibition and drainage stages were performed for all liquids. The Carman-Ergun equation was used for the permeability in the Leverett function. The differences in the capillary pressure curves of three liquids were correlated by the contact angles of liquids. For this aim, a correlation was defined for the imbibition and the drainage. In the presented study, the contact angles for three liquids with glass sphere were measured and the advancing and receding contact angles were used for the imbibition and drainage, respectively, in the correlation.