The dynamics of fattening and thinning 2D sessile droplets.
File(s)
Accepted version
Author(s)
Pradas, M
Savva, N
Benziger, JB
Kevrekidis, IG
Kalliadasis, S
Type
Journal Article
Abstract
We investigate the dynamics of a droplet on a planar substrate as the droplet volume changes dynamically due to liquid being pumped in or out through a pore. We adopt a diffuse-interface formulation which is appropriately modified to account for a localized inflow-outflow boundary condition (the pore) at the bottom of the droplet, hence allowing to dynamically control its volume, as the droplet moves on a flat substrate with a periodic chemical pattern. We find that the droplet undergoes a stick-slip motion as the volume is increased (fattening droplet) which can be monitored by tracking the droplet contact points. If we then switch over to outflow conditions (thinning droplet) the droplet follows a different path (i.e. the distance of the droplet midpoint from the pore location evolves differently) giving rise to a hysteretic behavior. By means of geometrical arguments we are able to theoretically construct the full bifurcation diagram of the droplet equilibria (positions and droplet shapes) as the droplet volume is changed, finding excellent agreement with time-dependent computations of our diffuse-interface model.
Date Issued
2016-04-14
Date Acceptance
2016-04-14
Citation
Langmuir, 2016, 32 (19), pp.4736-4745
ISSN
0743-7463
Publisher
American Chemical Society
Start Page
4736
End Page
4745
Journal / Book Title
Langmuir
Volume
32
Issue
19
Copyright Statement
This document is the Accepted Manuscript version of a Published Work that appeared in final form in Langmuir, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://dx.doi.org/10.1021/acs.langmuir.6b00256
Sponsor
Commission of the European Communities
Engineering & Physical Science Research Council (EPSRC)
Engineering & Physical Science Research Council (EPSRC)
Grant Number
247031
EP/L020564/1
EP/L027186/1
Subjects
Chemical Physics
MD Multidisciplinary
Publication Status
Published