(237j) Analysis of the Effect of Wetting Film on Two-Phase Flow in a Micromodel Porous Pattern: A CFD Approach

Analysis of fluid flow in porous media is an important topic in different fields of studies. The size and distribution of the pores and the competition between capillary and viscous forces in a porous medium significantly influence the displacement of multiple phases within a porous medium. For a flow of two immiscible fluids in a pore network medium, there are different parameters that control the displacement pattern among which the interfacial tension, wettability and wetting phase layer are of great importance. For many years, micromodel experiments and their simulation have been used as a reliable method to study the effect of various parameters on fluids displacement and the governing mechanisms involved. In this regard, CFD technique has provided a powerful tool for simulating the fluid flow in various physical systems. Upon verification of the CFD results with some experimental or physical data, it can be used to further extend our knowledge about the process of interest for a wider range of variables and test conditions.

Presence of multiphase flow and interactions between different phases make fluid flow analyzing more difficult. Wettability effect is one of the decisive parameters that should be taken into account. In multiphase flow, the phase with higher wettability magnitude (wetting phase) can spread over the surface and create a wetting film. The importance of this wetting film and its effects on fluid flow is investigated in this study. The volume of fluid(VOF) method is implemented to simulate two-phase immiscible displacement in a micromodel porous pattern. These numerical simulations are conducted for cases with and without wetting film. In the end, it was observed that the presence of wetting film in imbibition process reduced both the breakthrough time and final remained saturation of non-wetting phase. The contrast between cases with wetting film and cases without that is more severe in low capillary numbers (Capillary dominant flow).