Capillary Effects in Immiscible Flows in Heterogeneous Porous Media

Abstract

PACS. 47.66M -Flow through porous media. PACS. 06.40 -Fluctuations phenomena, random processes, and Brownian motion. PACS. 47.66K -Multiphase flows (inc. phase transitions in flow).

Experimental study on the two phase flow behavior in PEM fuel cell parallel channels with porous media inserts

“…The analogy between mini-channels and random porous media in terms of the two phase flow behavior has been reported by many researchers [21][22][23][24]. Particularly for PEM fuel cell channel flow, Wang et al [11] proposed a model to study the channel flow and theoretically obtained the solutions for two phase flow in fuel cell channels.…”

Capillary Effects in Heterogeneous Porous Media: Experiments, Pore Network Simulations, and Continuum Modeling

“…Taking a reference characteristic for imbibition processes involving frontal displacement. At value k*, the dimensionless function 1 = Jklk*, which steady-state flow, the continuum predictions were tested roughly follows the variation of an average pore size, is with experiments and found to be in good agreement [7].…”

“…It was found in [7] and [10] that for decreasing permeability (a < 0), the saturation builds up from its upstream value Uj (F(Ui) = Fi) in the high permeability region, x < x_, to a maximum value u_ (at x = x_), before it declines continuously inside the region of permeability variation (x_ < x < x+) to its asymptotic value Ui (Figure 1). For x+ ~ x the saturation remains constant at Uj until another heterogeneous region IS encountered.…”

“…However, this depends on geometric and flow properties. In immiscible displacement at sufficiently low capillary numbers, for example, permeability gradients have effects similar to gravity, leading to gradient percolation patterns (both stable and unstable) [6]; sharp changes in permeability in the direction of flow significantly change steady-state saturation profiles [7]; random distribution of permeabilities attributes large-scale percolation features (such as large-scale trapping) to displacements [8]; while correlated fields drastically alter the percolation aspects of the displacement [9]. All these capillary effects are driven by permeability heterogeneity and they are absent in miscible displacement.…”

Rate enhancement in unconventional gas reservoirs by wettability alteration

“…The saturation shock may highly affect well productivity index. However, steady-state solutions for two-phase linear flows have been presented for uniform rock wettability only (Barenblatt et al, 1990;Chaouche et al, 1993;Van Lingen et al, 1996;Huang and Honarpour, 1998). Analytical models accounting for wettability variation along the core or near to fracture face and wellbore are not available in the literature.…”