A novel method to evaluate dispersion stability of nanofluids

In this study, a new method is introduced to track the temporal changes of the particle volume fraction and size distribution, and the effects of the change of the nanofluid thermal conductivity are scrutinized. Five different nanofluids are generated: DI water/Al2O3, DI water/SiO2, DI water/Ag, EG/Al2O3, and EG/ZnO. The particle volume fraction change is identified by monitoring the suspension density using a hydrometer, and the particle size distribution change is analyzed using the dynamic light scattering (DLS) method. The thermal conductivity of each of the nanofluids is measured using the transient hot-wire method. From the analysis of the data, the nanofluid thermal conductivity is found to be affected by the changes in concentration and the particle size distribution.