Heat transfer studies on ethylene glycol/water nanofluid containing TiO2 nanoparticles

An experimental investigation has been carried out to study the heat transfer characteristics of ethylene glycol/water mixture(60:40) appended with TiO2 nanoparticles. The effect of volume fraction and Reynolds number are studied. Stable nanofluid is prepared using two-step method. Thermal conductivity and viscosity data required for the calculation of various heat transfer parameters are measured. The maximum enhancement in thermal conductivity is 24%(at volume fraction 0.8% and temperature 50 degrees C) and the corresponding increase in viscosity is 16%. An experimental set up was designed and fabricated to conduct forced convection studies. For convection studies the volume fraction is varied from 0.2 to 0.5% and Reynolds number from 850 to 2050. The nanofluid has better heat transfer characteristic compared to base fluid. The heat transfer enhancement is influenced by thermal properties of the nanofluid, particle concentration and Reynolds number. The maximum enhancement in heat transfer coefficient is 116% with Reynolds number of 2050 and 0.5% volume fraction. (C) 2019 Elsevier Ltd and IIR. All rights reserved.