Phase field modeling of Taylor flow in mini/microchannels, Part II: Hydrodynamics of Taylor flow

Abstract

This paper reports the results of a finite element implementation of the phase field method for the simulation of Taylor flow in mini/microchannels. Certain characteristics of Taylor flow have been frequently investigated in the literature using conventional modeling approaches but are relatively less frequently investigated using the phase field formulation, the focus of the present study. Modeling of wall adhesion has been studied by means of a simpler spinodal decomposition problem that isolates the phase field equations from those used to govern the flow hydrodynamics. Next, studies on two-phase flow are based on the phase distribution, flow field and pressure distribution in the computational domain. The current predictions are compared against select simulations performed with the volume of fluid model. The ability of both models to capture the thin liquid film between the bubble and channel wall is assessed and directions for future work are provided. The absence of unphysical parasitic velocity currents from the phase field results is demonstrated. The pressure distribution was characterized by the absence of interfacial oscillations in pressure that were shown to be present with the volume of fluid model. These can be considered major advantages of the phase field model over alternative approaches. Lastly, the effect of channel inlet configuration is studied and discussed.