CAPILLARY-FLOW PHENOMENA AND WETTABILITY IN POROUS-MEDIA .2. DYNAMIC FLOW STUDIES

The dynamics of capillary penetration of liquids into packs of monodisperse spherical beads of varying surface energy have been studied. Square-root-of-time dependence has been shown to be obeyed in horizontal one-dimensional flow for all media. The STVF model of Miller and Miller was shown to be valid for similar media of varying particle sizes and for liquids with different physical properties but exhibiting the same contact angle. The rates of horizontal one-dimensional flow of liquids exhibiting finite contact angles with polymethylmethacrylate-coated and siliconized beads, reported as reduced sorptivities and reduced penetrabilities, were found to deviate from values calculated for known contact angles using the cylindrical tube model of Washburn.