Al2O3/TiO2 hybrid nanofluids thermal conductivity

An experimental approach
  • Georgiana Madalina Moldoveanu
  • Alina Adriana Minea
  • Gabriela Huminic
  • Angel Huminic


This research deals with experimental studies on thermal conductivity variation of Al2O3 and TiO2 hybrid nanofluids with water as the base fluid. In addition, Al2O3 and TiO2 nanofluid mixtures were used for evaluation. The prepared samples were tested for determination of thermal conductivity at room temperature as well as at different temperatures. A comprehensive regression analysis was accomplished to link the experimental data sets with volume fractions for all prepared new fluids, as well as with temperature variation. The experimental results were finally linked to an evaluation of Mo number and heat transfer efficiency for possible solar energy uses. Results indicated that the hybrid nanofluids possess upper thermal conductivity if related to water and can successfully replace it in heat transfer applications.


Nanoparticles Thermal conductivity Hybrid nanofluid Mo number Solar 

List of symbols


Diameter (m)


Empirical shape factor


Temperature (K)


Accuracy of the fitted equations (–)


Estimated standard uncertainty (–)

Greek symbols


Thermal diffusivity (m2 s−1)


Dynamic viscosity (kg ms−1)


Particle volume fraction (–)



Heat transfer efficiency



Base fluid


Hybrid nanofluid


Refers to mass










Refers to volume



The authors would like to acknowledge that this research was possible with the support of the COST action CA 15119: Nanouptake—Overcoming Barriers to Nanofluids Market Uptake.


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2018

Authors and Affiliations

  1. 1.Faculty of Materials Science and EngineeringTechnical University “Gheorghe Asachi” of IasiIasiRomania
  2. 2.Faculty of Mechanical EngineeringUniversity Transilvania of BrasovBrasovRomania

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