Convective Heat Transfer Characteristics of TiO_2-EG Nanofluid as Coolant Fluid in Heat Exchanger

摘要

Working fluids in heat exchanger commonly used water or ethylene glycol with their advantages and disadvantages. There was a development to disperse nanoparticles into base fluids, or known as nanofluids, to resolve the disadvantages of the working fluid. Nanoparticles gave fluids unique characteristics including an increase in heat transfer. Therefore, nanofluids had better heat transfer characteristics compared to conventional working fluids. This article discussed the effect of adding nanoparticles in TiO_2-ethylene glycol nanofluid towards the heat transfer characteristics (Nusselt, Reynolds, ΔT LMTD, convective coefficient, overall heat transfer coefficient, and heat transfer) using heat exchanger device. The variation of nanoparticle concentrations in this research were 0%, 0.025%, 0.05%, and 0.075%. This research used laboratory-scaled heat exchanger type shell and tube as the heat transfer device, with the volumetric flow rate variations of 0.2, 0.4, and 0.6 1/m for each nanofluid sample. The test results showed that there was an increase along with the increasing nanofluid volumetric flow rate and the new nanoparticle concentrations.