Local wettability reversal during steady-state two-phase flow in porous media

Abstract

We study the effect of local wettability reversal on remobilizing immobile fluid clusters in steady-state two-phase flow in porous media. We consider a two-dimensional network model for a porous medium and introduce a wettability alteration mechanism. A qualitative change in the steady-state flow patterns, destabilizing the percolating and trapped clusters, is observed as the system wettability is varied. When capillary forces are strong, a finite wettability alteration is necessary to move the system from a single-phase to a two-phase flow regime. When both phases are mobile, we find a linear relationship between fractional flow and wettability alteration.

Dynamic Wettability Alteration in Immiscible Two-phase Flow in Porous Media: Effect on Transport Properties and Critical Slowing Down

“…Moreover, increase in F is higher for the lower capillary number, indicating that wettability alteration is very significant in the case of oil recovery, as Ca can go as low as 10 −6 in the reservoir pores. Fractional flow also obeys the symmetry relation F ′ (S) = 1 − F (1 − S) [23] which implies that, if the wetting angle of any pore is allowed to change all way down to zero degree (θ = 0 • ), the system will eventually become pure water-wet with time.…”

Bubble dynamics and heat transfer on a wettability patterned surface

“…However, on a wettability patterned surface, the liquid film is modulated by the surface wetting/non-wetting energy which modify the instability wavelength. According to Sinha et al [37], a change in the system wettability causes a perturbation in the system's flow pattern to destabilize any percolating and trapped immobile clusters appeared in the steady state. This implied that the perturbation of wettability patterns may affect the bubble departure diameter and frequency.…”

Rheology of Immiscible Two-phase Flow in Mixed Wet Porous Media: Dynamic Pore Network Model and Capillary Fiber Bundle Model Results

“…These experimental findings show the importance of understanding the effect of wettability even further, which is easier to do through analytical and numerical studies where large range of wetting conditions can be examined in short time. In the papers by Sinha et al (2011) and Flovik et al (2015), pore network models similar to the one used in the present article were used to investigate the effect of wettability alteration due to changes in salinity in oil-brine mixtures. The wettability alterations were done by changing between either complete wetting and complete non-wetting conditions in the first article (Sinha et al 2011), and by changing the wetting angles continuously between two limits depending on the cumulative flow of the wetting phase in the second article (Flovik et al 2015).…”

“…In the papers by Sinha et al (2011) and Flovik et al (2015), pore network models similar to the one used in the present article were used to investigate the effect of wettability alteration due to changes in salinity in oil-brine mixtures. The wettability alterations were done by changing between either complete wetting and complete non-wetting conditions in the first article (Sinha et al 2011), and by changing the wetting angles continuously between two limits depending on the cumulative flow of the wetting phase in the second article (Flovik et al 2015). The results from both show that local alterations of the wettability introduce qualitative changes in the flow patterns by destabilizing the trapped clusters.…”