On numerical modeling of capillary flow dynamics in a microchannel model by using the finite element method

A simple microchannel model with submillimeter-scale geometries is proposed for studying capillary flows and investigating the dynamics in the channel. The finite element method incorporating surface tension and two-phase flow characteristic is applied. Velocity and pressure fields in the microchannel are presented. It is shown that the capillary-phase front in the microchannel is stirred, suffering small oscillations and retreating from the previous position before traveling again. Such a phenomenon is caused by nonlinear interaction of the capillary flow, surface tension, and boundary conditions.