INVESTIGATION OF NEWTONIAN AND NON-NEWTONIAN DROPLETS IN COLLISION WITH THE HEATED ULTRAPHOBIC SURFACE ON VARIOUS WEBER NUMBERS

Year 2017, , 1129 - 1135, 01.04.2017

Morteza Bayareh

https://doi.org/10.18186/thermal.298612

Abstract

Super
hydrophobic surfaces due to water repelling property, have a considerable
potential for the use in various modern technologies. In this paper, the
collision between Newtonian
and non-Newtonian droplets with a super-hydrophobic hot surface like graphite
has been simulated. The contact angle is 140 and 160 degree. Simulation yielded
proper result compared to the experimental results. It is found that the temperature
effect on hydrophobic surfaces is negligible. Our results demonstrate that the
dimensionless drop diameter increases with the Weber number. It is revealed
that a Newtonian droplets shows different behavior compared to a non-Newtonian
one especially at higher temperatures.     

Keywords

Hydrophobic surfaces, VOF method, Weber number, Newtonian Droplet, Non-Newtonian droplets

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