Enhancement of Electrical Conductivity of Water Based Silicon Oxide Nanofluids

In this paper, the electrical conductivity of SiO2 nanofluids using pure water (H2O) as the base fluid is investigated. The two-step method was used to prepare the SiO2-H2O nanofluids. The variations in electrical conductivity of SiO2-H2O nanofluids as function of mass concentration of 0.1-1.0% and temperature of 25.2-64.3 are present. Experimental results show that the correlation of electrical conductivity of SiO2-H2O nanofluids and mass concentration, temperature is nearly linear. However, the effect of temperature on electrical conductivity is much less than that of mass concentration. In order to evaluate the enhancement performance of SiO2-H2O nanofluids, the relative electrical conductivity is introduced and studied explicitly. The relative electrical conductivity means the ratio between the electrical conductivity of SiO2-H2O nanofluids to pure water. It is found that the relative electrical conductivity increases with the increase of mass fraction and decreases with the increase of temperature. Finally, an empirical correlation is built to predict the electrical conductivity with varied combination of mass fraction and temperature.