Droplet dynamics on chemically heterogeneous substrates
File(s)
Accepted version
Author(s)
Savva, Nikos
Groves, Danny
Kalliadasis, Serafim
Type
Journal Article
Abstract
Slow droplet motion on chemically heterogeneous substrates is considered analytically and numerically. We adopt the long-wave approximation which yields a single partial differential equation for the droplet height in time and space. A matched asymptotic analysis in the limit of nearly circular contact lines and vanishingly small slip lengths yields a reduced model consisting of a set of ordinary differential equations for the evolution of the Fourier harmonics of the contact line. The analytical predictions are found, within the domain of their validity, to be in good agreement with the solutions to the governing partial differential equation. The limitations of the reduced model when the contact line undergoes stronger deformations are partially lifted by proposing a hybrid scheme which couples the results of the asymptotic analysis with the boundary integral method. This approach improves the agreement with the governing partial differential equation, but at a computational cost which is significantly lower compared to that required for the full problem.
Date Issued
2019-01-25
Date Acceptance
2018-09-04
Citation
Journal of Fluid Mechanics, 2019, 859, pp.321-361
ISSN
0022-1120
Publisher
Cambridge University Press (CUP)
Start Page
321
End Page
361
Journal / Book Title
Journal of Fluid Mechanics
Volume
859
Copyright Statement
© 2018 Cambridge University Press
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000450425600012&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Grant Number
EP/L020564/1
Subjects
Science & Technology
Technology
Physical Sciences
Mechanics
Physics, Fluids & Plasmas
Physics
contact lines
drops
interfacial flows (free surface)
CONTACT-ANGLE HYSTERESIS
SOLID-SURFACE
WETTABILITY GRADIENT
PATTERNED SURFACES
VISCOUS DROPLET
THIN DROP
MOTION
LINE
SIMULATION
MOVEMENT
Publication Status
Published
Date Publish Online
2018-11-16