Rubén Bãnos and José Arcos and Oscar Bautista and Federico Méndez
Oscillatory Electroosmotic Flow of PowerLaw Fluids in a Microchannel
773 - 776
2018
12
8
International Journal of Mechanical and Mechatronics Engineering
https://publications.waset.org/pdf/10009307
https://publications.waset.org/vol/140
World Academy of Science, Engineering and Technology
The Oscillatory electroosmotic flow (OEOF) in power
law fluids through a microchannel is studied numerically. A
timedependent external electric field (AC) is suddenly imposed
at the ends of the microchannel which induces the fluid motion.
The continuity and momentum equations in the x and y direction
for the flow field were simplified in the limit of the lubrication
approximation theory (LAT), and then solved using a numerical
scheme. The solution of the electric potential is based on the
DebyeH&uml;uckel approximation which suggest that the surface potential
is small,say, smaller than 0.025V and for a symmetric (z z)
electrolyte. Our results suggest that the velocity profiles across
the channelwidth are controlled by the following dimensionless
parameters the angular Reynolds number, Re&omega;, the electrokinetic
parameter, &macr;&kappa;, defined as the ratio of the characteristic length scale
to the Debye length, the parameter &lambda; which represents the ratio
of the HelmholtzSmoluchowski velocity to the characteristic length
scale and the flow behavior index, n. Also, the results reveal that
the velocity profiles become more and more nonuniform across the
channelwidth as the Re&omega; and &macr;&kappa; are increased, so oscillatory OEOF
can be really useful in microfluidic devices such as micromixers.
Open Science Index 140, 2018