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Attractive Encounter of a Nanodrop toward a Nanoprotrusion
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posted on 2017-03-22, 00:00 authored by Yu-En Liang, Yu-Hsuan Weng, I-Fan Hsieh, Heng-Kwong Tsao, Yu-Jane ShengThe
encounter of a nanodrop with a nanoprotrusion on a hysteresis-free
surface is explored by many-body dissipative particle dynamics (MDPD)
and surface evolver (SE). On a smooth surface, a nanodrop exhibits
random motion but will be captured as it encounters a protrusion.
For both lyophilic and lyophobic systems, there exists an attraction
between the drop and the protrusion. The potential energy profiles
associated with the detachment processes with and without crossing
the protrusion are acquired by the determination of the displacement
of the captured drop responding to the externally applied forces.
It is found that the critical force and depth of the energy well of
the lyophilic system are greater than those of the lyophobic system.
Moreover, the drop straddling on the protrusion symmetrically is stable
for the lyophilic system but becomes unstable for the lyophobic system.
Our results can shed some light on the effect of surface roughness
on droplet wetting.