Effects of surface tension on two-dimensional two-phase stratified flows

The effect of surface tension on a stratified two-phase flow between parallel plates was investigated using the level-set (LSET) method along with a proposed localized mass correction (LMC) method. Accurate evaluation of the interface curvature was essential as the surface tension force is proportional to the interface curvature. The LSET method offered the most convenient way to calculate the curvature of the interface. The surface tension force was modeled using the continuum surface force (CSF) model. It was observed that the surface tension effect is confined to the developing region where the interface curvature is nonzero. The results that were obtained from the LSET method were similar to those of the volume-of-fluid (VOF) that also used the CSF model. It was also found that surface tension was confined to the developing region where the interface curvature is nonzero.