Impact analysis of natural convection on thermal conductivity measurements of nanofluids using the transient hot-wire method

摘要

Significant deviations between published results have been reported measuring the effective therma conductivity of nanofluids with the transient hot-wire method (THWM). This may be attributed to a poo selection of the temperature data range, which should meet the following conditions. The start tin* should be chosen after the conductive heat flux delay time, while the end time should be selected befor a crossover point when natural convection becomes significant. Considering an EG-based 1.06 vol.% Zn( nanofluid, the thermal conductivity was measured to increase by 5.4% over that of the base fluid.