1 research outputs found
Combined Effects of Surface Roughness and Wetting Characteristics on the Moving Contact Line in Microchannel Flows
The present study investigates moving
contact lines in microfluidic
confinements with rough topographies modeled with random generating
functions. Using matched asymptotic expansion, the description of
the whole contact line is obtained and the dynamic contact angle is
extracted by extrapolating the bulk meniscus to the channel wall.
Significant variations are observed in the contact angle because of
the heterogeneities of the confining walls of the microfluidic channel.
The effects of the surface wetting condition also play a crucial role
in altering the description of the contact line bearing particular
nontrivial interactions with the topological features of the solid
boundaries. In an effort to assess the underlying consequences, two
different surface wetting conditions are studied; namely, complete
wetting substrate and partial wetting substrate. Our studies reveal
that the consequent wetting characteristics are strongly influenced
by action of intermolecular forces in presence of surface roughness.
The effect of slip, correlation length, and roughness parameters on
the dynamic contact angle have been also investigated