Effect of nano particles on electrical conductivity and viscosity subject to a cyclic temperature pattern

摘要

The paper investigates the effect of thermal loading on viscosity and electrical conductivity of weakly dosed nanofluids. Two types of thermal loadings are examined: (a) a continuous increasing loading from sub-ambient 5ï??°Cto 40ï??°C, (b) a heating (5ï??°Cï??®45ï??°C) followed by cooling (45ï??°Cï??®5ï??°C) loading. Results show that electrical conductivity is weakly dependent on thermal loading and is strongly dependent on nano-particle type. Viscosity shows a strong relationship with thermal loading but is weakly nano-particle dependent. Both electrical conductivity and viscosity show weak hysteresis during the cyclic thermal loading for low dosages. This finding is in contrast for a strong hysteresis pattern reported by Nguyen et al.[1] for highly dosed nanofluids.