Enhancement of heat transfer performance in pipe flow using graphene-oxide-nanofluid and its application

Abstract

This paper aims to introduce heat transfer performance of aqueous suspensions in horizontal tube and heat pipe cooling device under constant heat flux condition. Here, pure water and graphene oxide (GO) nanofluid are employed as a working fluid. Consideration is given to the effects of particle concentration on heat transfer enhancement. It is found for pipe flow case that (i) heat transfer enhancement is caused by suspending nanoparticles, (ii) viscosity of GO nanofluid developed here is decreased with an increase in temperature, (iii) but the pressure drop for GO nanofluid, at 293 K, is almost the same as that of pure water, because volume fraction of particles is substantially low. When GO nanofluid is used in a Cu heat pipe cooling device, one observes that (i) thermal performance of heat pipe increases with increasing the concentration of GO nanoparticles in the base fluid, (ii) GO/water nanofluid shows lower thermal resistance compared to pure water, and (iii) heat transfer coefficient of the GO nanofluid in Cu heat pipe significantly increases with an increase in heat flux and GO nanoparticles concentration. This is explained as due to formation of rough inner surface in Cu heat pipe which supports higher heat transfer in GO nanofluid as compared to pure water.