Abstract
The performance of the hybrid nanofluid of ND + Fe3O4/water was investigated for particle loadings of 0.05%, 0.1%, and 0.2% and the Reynolds number in the range from 2000 to 22,000, and compared to the performance of other hybrid nanofluids available in literature. The evaluation of the thermophysical properties shows that the thermal conductivity of the hybrid nanofluid is higher than those of the base fluid by 17.76% and the viscosity is higher by 72.91% at volume concentration of 0.2% and at 60 degrees C. The study shows the influence of the use of ND + Fe3O4/water nanofluid in terms of Reynolds number and for various volume fractions of nanoparticles on the heat transfer, friction factor, pumping power requirement, entropy generation, and exergy efficiency. The results show that Nusselt number can be increased by 29.5% over the base fluid if 0.2 vol.% ND + Fe3O4/water nanofluid is used, but also resulted in an increase of the pumping power requirement by 39.44%. Thermal performance factor can be as high as 1.25-times for 0.2 vol.% ND + Fe3O4/water nanofluid. The use of 0.2 vol.% ND + Fe3O4/water nanofluid resulted in an increase of the exergy efficiency of 26.96%, and a drop of the entropy generation by 44.33% at a Reynolds number of 20,095, against water data.