Validation of direct pore scale modeling approaches to wettability

Bibliography:

Raul Verma, Matteo Icardi, Masa Prodanovic, Validation of direct pore scale modeling approaches to wettability, submitted March 2015

Authors:

Raul Verma, Matteo Icardi, Masa Prodanovic

Keywords:

Validation of direct pore scale modeling approaches to wettability

Year:

2015

Abstract:

Understanding of pore-scale physics for multiphase ﬂow in porous media is essential for accurate description of various ﬂow phenomena. In particular, capillarity and wettability strongly inﬂuence capillary pressure-saturation and relative permeability relationships. Wettability is quantiﬁed by the con- tact angle of the ﬂuid-ﬂuid interface at the pore walls. In this work we com- pare the interface capturing method implemented in a popular open-source ﬁnite volume computational ﬂuid dynamics solver with a new formulation of the level set method that models capillarity-dominated ﬂow and is less computationally expensive. The methods fundamentally diﬀer in the way they mesh porous geometry and capture interfaces, as well as in the num- ber of equations solved and other implementation and algorithmic details. Both methods are able to solve curvature-driven ﬂow and implement arbi- trary contact angles at pore walls. The methods are tested in rhomboidal packings of spheres for a range of contact angles and for diﬀerent rhom- boidal conﬁgurations. Predictions are validated against the semi-analytical solutions obtained by Mason and Morrow (1994). We speciﬁcally focus on evaluating the accuracy of each method (algebraic VOF and level-set) and beneﬁts and limitations of employing a less computationally intense method for semi-equilibrium capillary-dominated ﬂows vs. the full approximation of the Navier-Stokes equation applicable also to inertial and viscous ﬂows. Consequences for larger and more complex problems are also considered.

ISSN:

2015