An experimental investigation into the effect of particle mixture ratio on specific heat capacity and dynamic viscosity of Al2O3-ZnO hybrid nanofluids

• Published in: Powder technology 2020-03, Vol.363, p.699-716
• Main Authors: Wole-Osho, Ifeoluwa, Okonkwo, Eric C., Kavaz, Doga, Abbasoglu, Serkan
• Format: Article
• Language: English
• Subjects: Al2O3; Aluminum oxide; Heat transfer; Hybrid nanofluids; Nanofluids; Nanoparticles; Specific heat; Viscosity; Viscosity measurement; Zinc oxide; ZnO
• ISSN: 0032-5910; 1873-328X
• DOI: 10.1016/j.powtec.2020.01.015

Hybrid nanofluids are gaining a wide range of applications due to their reported improvement in heat transfer properties. This study presents an experimental investigation into the specific heat and viscosity of Al2O3-ZnO water hybrid nanofluids at three mixture ratios. The specific heat and viscosity measurements are taken over different temperatures at different volume concentrations. The study compared the experimental data to classical models and observed that the specific heat model overestimated and the viscosity model underestimated experimental obtained values. According to results, the particles mixture ratio has a significant effect on both specific heat and viscosity of the hybrid nanofluids. Viscosity increases while specific heat decreases by increasing the volume concentration. Al2O3-ZnO water hybrid nanofluids at 2:1 mixture ratio have a maximum viscosity increase of 96.37% and maximum specific heat decrease of 30.12% at a temperature of 25 °C and volume concentration 1.67%. [Display omitted] •The specific heat and viscosity of Al2O3-ZnO dispersed in water is investigated.•Al2O3-ZnO water nanofluids at 2:1 mixture ratio have a maximum viscosity increase of 96.37%.•Maximum specific heat decrease of the Al2O3-ZnO water nanofluids was 30.12%.•Al2O3-ZnO hybrid nanofluid at 1:1 mixture ratio is most ideal for heat transfer application.•Theoretical models do not account for the effect of mixture ratio in the nanofluid.