Efficient Condensation and Droplet Removal on Electrowetting- Functionalized Surfaces

Davood Baratian (Contributor), Ranabir Dey (Contributor), Harmen Hoek (Contributor), van den Ende, H. T. M. (Contributor), Mugele, F. G. (Invited speaker)

Activity: Talk or presentationInvited talk

Description

Efficient condensation of vapor and collection of fog from the atmosphere
are important to life in arid environments. Nature has come up
with various strategies to optimize the processes by a combination of
both topographic and chemical functionalization of solid surfaces that
are imprinted passively into the structure of the surface. One crucial
aspect in this process is the removal of liquid from the solid surface
once it has condensed. In here, we present a novel active approach to
improve the efficiency of vapor condensation onto hydrophobic surfaces
that are functionalized by electrowetting. We fabricated electrowettingfunctionalized
surfaces with submerged interdigitated electrodes. Upon
exposure to supersaturated vapor droplets condense onto these surfaces
in an initially random pattern. As the droplets grow, electrowetting
mobilizes the growing drops and induces early coalescence, giving rise
to alignment of drops and to early shedding. Mobilization and early
shedding are controlled by the effective reduction of contact angle hysteresis
in AC electrowetting. Drops are found to grow algebraically,
initially with a self-similar growth law as in conventional drop condensation.
At a later stage, self-similarity is broken and the statistical
drop size distribution is altered. We discuss potential applications in
terms of heat transfer.
Period14 Mar 2018 - 17 Mar 2018
Held atDPG Spring Meeting of the Condensed Matter Section (SKM) together with the EPS (EPS-CMD) 2018
Event typeConference
LocationBerlin , Germany
Degree of RecognitionInternational