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Title: Steady states of thin film droplets on chemically heterogeneous substrates
Abstract We study steady-state thin films on chemically heterogeneous substrates of finite size, subject to no-flux boundary conditions. Based on the structure of the bifurcation diagram, we classify the 1D steady-state solutions that exist on such substrates into six different branches and develop asymptotic estimates for the steady states on each branch. Using perturbation expansions, we show that leading-order solutions provide good predictions of the steady-state thin films on stepwise-patterned substrates. We show how the analysis in one dimension can be extended to axisymmetric solutions. We also examine the influence of the wettability contrast of the substrate pattern on the linear stability of droplets and the time evolution for dewetting on small domains. Results are also applied to describe 2D droplets on hydrophilic square patches and striped regions used in microfluidic applications.  more » « less
Award ID(s):
2008255
PAR ID:
10221539
Author(s) / Creator(s):
;
Date Published:
Journal Name:
IMA Journal of Applied Mathematics
Volume:
85
Issue:
6
ISSN:
0272-4960
Page Range / eLocation ID:
980 to 1020
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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