Modelling the formation of structured deposits at receding contact lines of evaporating solutions and suspensions

Fraštia, Ľubor; Archer, Andrew J.; Thiele, Uwe

doi:10.1039/c2sm26574e

Cited by 64 publications

(107 citation statements)

References 105 publications

(285 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Even though a number of simplifying assumptions are made (in order to isolate the influences of concentration-dependent viscosity and diffusivity), dramatic changes in the dynamics are observed. In practice, many other phenomena may come into play, including partial wetting, more complex rheology (Jeong et al 2010;Hewitt & Balmforth 2013), particle adsorption and desorption at the liquid-air interface and in the contact-line region, evaporation (Fraštia, Archer & Thiele 2012), the effects of structural disjoining pressure (Trokhymchuk et al 2001;Matar et al 2007;Wasan et al 2011;Kondiparty et al 2012;Liu et al 2012), and three-dimensional dynamics. Nevertheless, by focusing on the important and physically relevant limiting case of perfectly wetting systems, the present work provides a foundation and motivation for examining these issues.…”

Section: Discussionmentioning

confidence: 99%

Forced spreading of films and droplets of colloidal suspensions

Espín

Kumar

2014

J. Fluid Mech.

View full text Add to dashboard Cite

When a thin film of a colloidal suspension flows over a substrate, uneven distribution of the suspended particles can lead to an uneven coating. Motivated by this phenomenon, we analyse the flow of perfectly wetting films and droplets of colloidal suspensions down an inclined plane. Lubrication theory and the rapid-vertical-diffusion approximation are used to derive a coupled pair of one-dimensional partial differential equations describing the evolution of the interface height and particle concentration. Precursor films are assumed to be present, the colloidal particles are taken to be hard spheres, and particle and liquid dynamics are coupled through a concentrationdependent viscosity and diffusivity. We find that for sufficiently high Péclet numbers, even small initial concentration inhomogeneities produce viscosity gradients that cause the film or droplet front to evolve continuously in time instead of travelling without changing shape as happens in the absence of colloidal particles. At high enough particle concentrations, particle diffusion can lead to the formation of long-lived secondary flow fronts in films. Our results suggest that particle concentration gradients can have a dramatic influence on interface evolution in flowing films and droplets, a finding which may be relevant for understanding the onset of patterns that are observed experimentally.

show abstract

Section: Discussionmentioning

confidence: 99%

Forced spreading of films and droplets of colloidal suspensions

Espín

Kumar

2014

J. Fluid Mech.

View full text Add to dashboard Cite

show abstract

“…Note, that the understanding of the bifurcation scenario of deposition processes is not only important for the dip-coating process at hand and the Langmuir-Blodgett transfer [31,32]. It is also relevant for line deposition from solutions and suspensions with volatile solvent where other instability mechanisms dominate, see, e.g., the case of evaporative dewetting [77,78]. It was pointed out in [77] and more extensively discussed in [32] that the onset of periodic deposition at the lower limiting velocity may be considered a depinning transition as beyond this critical velocity part of the steady meniscus profile depins and is dragged away from the bath as liquid ridge.…”

Section: Discussionmentioning

confidence: 99%

Self-organized dip-coating patterns of simple, partially wetting, nonvolatile liquids

et al. 2019

Self Cite

View full text Add to dashboard Cite

When a solid substrate is withdrawn from a bath of simple, partially wetting, nonvolatile liquid, one typically distinguishes two regimes, namely, after withdrawal the substrate is macroscopically dry or homogeneously coated by a liquid film. In the latter case, the coating is called a Landau-Levich film. Its thickness depends on the angle and velocity of substrate withdrawal. We predict by means of a numerical and analytical investigation of a hydrodynamic thin-film model the existence of a third regime. It consists of the deposition of a regular pattern of liquid ridges oriented parallel to the meniscus. We establish that the mechanism of the underlying meniscus instability originates from competing film dewetting and Landau-Levich film deposition. Our analysis combines a marginal stability analysis, numerical time simulations and a numerical bifurcation study via path-continuation.

show abstract

“…These asymptotic forms, truncated after a few terms, are used frequently throughout the literature (independently or as combinations of the two forms 1,25,43,44 ) even though they are only strictly valid for thick liquid films and cannot describe the binding potential as h → 0. To describe the small h behaviour, the full form of g(h) is required.…”

Section: The Binding Potentialmentioning

confidence: 99%

Liquid drops on a surface: Using density functional theory to calculate the binding potential and drop profiles and comparing with results from mesoscopic modelling

Hughes

Thiele

Archer

2015

The Journal of Chemical Physics

Self Cite

View full text Add to dashboard Cite

Citation: HUGHES, A.P., THIELE, U. and ARCHER, A.J., 2015. Liquid drops on a surface: using density functional theory to calculate the binding potential and drop profiles and comparing with results from mesoscopic modelling.Journal of Chemical Physics, 142 (7), 074702.Additional Information:• The contribution to the free energy for a film of liquid of thickness h on a solid surface due to the interactions between the solid-liquid and liquid-gas interfaces is given by the binding potential, g(h). The precise form of g(h) determines whether or not the liquid wets the surface. Note that differentiating g(h) gives the Derjaguin or disjoining pressure. We develop a microscopic density functional theory (DFT) based method for calculating g(h), allowing us to relate the form of g(h) to the nature of the molecular interactions in the system. We present results based on using a simple lattice gas model, to demonstrate the procedure. In order to describe the static and dynamic behaviour of non-uniform liquid films and drops on surfaces, a mesoscopic free energy based on g(h) is often used. We calculate such equilibrium film height profiles and also directly calculate using DFT the corresponding density profiles for liquid drops on surfaces. Comparing quantities such as the contact angle and also the shape of the drops, we find good agreement between the two methods. We also study in detail the effect on g(h) of truncating the range of the dispersion forces, both those between the fluid molecules and those between the fluid and wall. We find that truncating can have a significant effect on g(h) and the associated wetting behaviour of the fluid. C 2015 AIP Publishing LLC.[http://dx

show abstract

Modelling the formation of structured deposits at receding contact lines of evaporating solutions and suspensions

Cited by 64 publications

References 105 publications

Forced spreading of films and droplets of colloidal suspensions

Forced spreading of films and droplets of colloidal suspensions

Self-organized dip-coating patterns of simple, partially wetting, nonvolatile liquids

Liquid drops on a surface: Using density functional theory to calculate the binding potential and drop profiles and comparing with results from mesoscopic modelling

Contact Info

Product

Resources

About