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

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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