Extended methodology for determining wetting properties of porous media

Porous media represent a broad class of mesoscopically disordered materials that are important in many industrial processes, mostly involving the transport of fluids. For examples, the flow of oil and water in sedimentary rock determines the producibility of oil reservoirs; diffusion and dispersion of molecules in soil govern the spreading of both fertilizers and contaminants; chemical reactors use porous catalysts to enhance the mixing of reagents; the containment of chemical and nuclear wastes depends on the low permeability of concrete barriers. These are just a few problems familiar to our everyday lives. The study of porous media has traditionally been under the disciplines of chemical, mechanical, and petroleum engineering. Only in recent years has the field begun to attract the interest of physicists. The displacement of one fluid by another in a porous medium is now recognized as one of the archetypal systems for studying the physics of pattern formation and interface growth. Fluids transport is known to involve effects due to the microgeometry of the pores, the connectivity of the pore network, and the wetting properties of the pore surfaces. These are all fundamental scientific issues that require the understanding of the physics and chemistry associated with the porous materials. Tackling these problems requires the collaboration of scientists from many different disciplines. Although much work has been done and a great deal has been learned, many interesting and important issues remain. In an article written five years ago, I gave a pedagogical overview of some of the problems in porous media that captivated my own interest.

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Effect of wetting properties on the kinetics of drying of porous media

Journal of Physics Condensed Matter ◽

10.1088/0953-8984/19/11/112101 ◽

2007 ◽

Vol 19 (11) ◽

pp. 112101 ◽

Cited By ~ 46

Author(s):

N Shahidzadeh-Bonn ◽

A Azouni ◽

P Coussot

Keyword(s):

Porous Media ◽

Wetting Properties ◽

Kinetics Of

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Wetting and Spreading of Commercially Available Aqueous Surfactants on Porous Materials

Colloids and Interfaces ◽

10.3390/colloids3010014 ◽

2019 ◽

Vol 3 (1) ◽

pp. 14 ◽

Cited By ~ 5

Author(s):

Phillip Johnson ◽

Toby Routledge ◽

Anna Trybala ◽

Mauro Vaccaro ◽

Victor Starov

Keyword(s):

Contact Angle ◽

Porous Media ◽

Surfactant Concentration ◽

Degree Of Saturation ◽

Distilled Water ◽

Base Diameter ◽

Complete Wetting ◽

Wetting Properties ◽

Surfactant Solutions ◽

Aqueous Surfactants

The wetting properties of aqueous solutions of a commercially available surfactant at various concentrations on porous media are investigated using the KRUSS DSA100 shape analyzer and the ADVANCED software to process the data. Time evolution of both the contact angle and drop base diameter at each surfactant concentration after deposition were monitored. Three different porous substrates (sponges) were examined. The sponges used were a car sponge, dish sponge and audio sponge. The sponges were investigated both dry and at different degrees of saturation, that is, the amount of water absorbed into the sponge. It was found that pure distilled water droplets deposited on the dry porous media showed non-wetting. However, if droplets of surfactant solutions were deposited, then a change to a complete wetting case was found at all surfactant concentrations used. It has been observed that for all sponges, no matter the degree of saturation, they display a minimum contact angle after which the droplet is rapidly absorbed into the porous media.

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Burst Dynamics, Upscaling and Dissipation of Slow Drainage in Porous Media

Frontiers in Physics ◽

10.3389/fphy.2021.796019 ◽

2021 ◽

Vol 9 ◽

Author(s):

Knut Jørgen Måløy ◽

Marcel Moura ◽

Alex Hansen ◽

Eirik Grude Flekkøy ◽

Renaud Toussaint

Keyword(s):

Surface Tension ◽

Experimental Investigation ◽

Porous Media ◽

Energy Dissipation ◽

Correlation Length ◽

Fractal Dimensions ◽

Theoretical Framework ◽

Theoretical Description ◽

Wetting Properties ◽

Gravitational Forces

We present a theoretical and experimental investigation of drainage in porous media. The study is limited to stabilized fluid fronts at moderate injection rates, but it takes into account capillary, viscous, and gravitational forces. In the theoretical framework presented, the work applied on the system, the energy dissipation, the final saturation and the width of the stabilized fluid front can all be calculated if we know the dimensionless fluctuation number, the wetting properties, the surface tension between the fluids, the fractal dimensions of the invading structure and its boundary, and the exponent describing the divergence of the correlation length in percolation. Furthermore, our theoretical description explains how the Haines jumps’ local activity and dissipation relate to dissipation on larger scales.

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