Dynamics of spreading thixotropic droplets
File(s)
Published version
Author(s)
Uppal, AS
Matar, OK
Craster, RV
Type
Journal Article
Abstract
The e ect of thixotropy on the two-dimensional spreading of a sessile
drop is modelled using lubrication theory. Thixotropy is incorporated by the
inclusion of a structure parameter, , measuring structure build-up governed
by an evolution equation linked to the droplet micromechanics. A number of
models are derived for coupled to the interface dynamics; these range from
models that account for the cross-stream dependence of to simpler ones in
which this dependence is prescribed through appropriate closures. Numerical
solution of the governing equations show that thixotropy has a profound e ect
on the spreading characteristics; the long-time spreading dynamics, however,
are shown to be independent of the initial structural state of the droplet. We
also compare the predictions of the various models and determine the range
of system parameters over which the simple models provide su ciently good
approximations of the full, two-dimensional spreading dynamics.
drop is modelled using lubrication theory. Thixotropy is incorporated by the
inclusion of a structure parameter, , measuring structure build-up governed
by an evolution equation linked to the droplet micromechanics. A number of
models are derived for coupled to the interface dynamics; these range from
models that account for the cross-stream dependence of to simpler ones in
which this dependence is prescribed through appropriate closures. Numerical
solution of the governing equations show that thixotropy has a profound e ect
on the spreading characteristics; the long-time spreading dynamics, however,
are shown to be independent of the initial structural state of the droplet. We
also compare the predictions of the various models and determine the range
of system parameters over which the simple models provide su ciently good
approximations of the full, two-dimensional spreading dynamics.
Date Issued
2017-01-09
Date Acceptance
2017-01-07
Citation
Journal of Non-Newtonian Fluid Mechanics, 2017, 240, pp.1-14
ISSN
1873-2631
Publisher
Elsevier
Start Page
1
End Page
14
Journal / Book Title
Journal of Non-Newtonian Fluid Mechanics
Volume
240
Copyright Statement
© 2017 The Authors. Published by Elsevier B.V.
This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Grant Number
EP/L020564/1
Subjects
Science & Technology
Technology
Mechanics
Thixotropy
Lubrication theory
Droplets
Spreading
FLUID
MODEL
FLOW
Polymers
01 Mathematical Sciences
02 Physical Sciences
09 Engineering
Publication Status
Published