Heat transfer and pressure drop investigation of graphene nanoplatelet-water and titanium dioxide-water nanofluids in a horizontal tube

A continuous increase in energy consumption lead to more effective solutions for efficient use of energy in thermal systems. In order to save energy by improving the thermo-hydraulic performance of heat exchangers, a numerical and experimental study carried out on the thermo-hydraulic performance of Graphene nanoplatelet and Titanium dioxide nanoparticle addition to water flow through a horizontal tube. Graphene nanoplatelet (high price) and Titanium dioxide(low price) nanoparticles, which are frequently used in previous studies, were compared for the first time in order to provide users with a perspective in terms of therrno-hydraulic performance. The study was experimentally and numerically conducted with nanofluid weight fractions of 0.5%, 0.75% and 1.0% and the flow under turbulent conditions. The highest Nusselt number obtained Is 133.61 for the Titanium dioxide-water nanofluid and 173.54 for the Graphene nanoplatelet-water nanofluid with the weight fraction of 1.00%. Moreover, the friction factor results of Graphene nanoplatelet-water and Titanium dioxide-water nanofluids are close to each other at same Re number.