Heat Transfer in Variable Viscosity Micro-Channel Flow of EG-Water/Ag Nanofluids with Convective Cooling

Abstract:

Thermal decomposition of a variable viscosity nanofluid containing ethylene glycol (EG)-water mixture with silver (Ag) nanoparticles in a micro-channel with convective heat exchange at the walls is investigated. The model equations for momentum and energy balance are obtained and transformed into a nonlinear boundary value problem using lubrication approximation theory and tackled semi-analytically via perturbation method coupled with Hermite-Padé approximation techniques. EG to water volume ratios examined are 0:100%, 20:80%, 40:60%, 60:40%, 80:20% and 100:0% while the Ag nanoparticles volume fraction utilised are 0%, 5% and 10%. It is found that the critical Eckert number for nanofluid thermal stability and the Nusselt number are enhanced with an increase in the nanoparticles volume fraction while an increase of EG volume ratio in the base fluid lessens the critical Eckert number.

• Periodical: Defect and Diffusion Forum (Volume 387)
• Pages: 182-193
• DOI: https://doi.org/10.4028/www.scientific.net/DDF.387.182
• Online since: September 2018
• Authors: Oluwole Daniel Makinde*
• Keywords: Convective Cooling, Ethylene Glycol-Water Mixture, Micro-Channel Flow, Silver Nanoparticles, Variable Viscosity

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