Experimental studies on thermal conductivity of blends of ethylene glycol-water-based TiO2 nanofluids

A set of three nanofluids of different blends were prepared with ethylene glycol–water and TiO₂ nanoparticles and are characterized for thermal conductivity as a function of temperature and volume concentration of nanoparticles. The measurements were taken in the temperature range from 30 °C to 70 °C, which happens to be most widely used range of temperature for many cooling applications in heat transfer equipment. Nanofluids were prepared by dispersing the nanoparticles in base fluids such as (1) water, (2) ethylene glycol plus water in the ratio of 40%:60% and 3) ethylene glycol plus water in the ratio of 50%:50% by weight. Based on the experimental results, it is observed that the thermal conductivity of TiO₂ nanofluids, considered in the present investigation, increases with increase in percentage of volume concentration of TiO₂ and also with temperature. Current experimental investigation presents valuable data on the measured thermal conductivity of TiO₂ nanofluids for very low volume concentrations from 0.2% to 1.0% of nanoparticles in the temperature range of 30 °C–70 °C.