An Experimental Investigation And Modelling Into Thermal Conductivity Of Nanofluids

Abstract

In this study, the thermal conductivity of manufactured ZnO-water, ZnO-ethylene glycol, single wall carbon nanotubes (SWCNT)-water and silver aqueous solution nanofluids have been evaluated. The effect of sonication time, settling time, temperature, particle size and volume fraction have been studied on the thermal conductivity of manufactured nanofluids. The results shows as the sonication time increases (0-8 hours), the maximum enhancement in the thermal conductivity of ZnO-water and ZnO-ethylene glycol nanofluids are 11.3% and 3.5% respectively of volume fraction 0.05% at a temperature 25° C. The thermal conductivity of nanofluids decreases as the settling time rises. The effect of sonication power (140-220 W) of volume fraction 1% has been studied on the thermal conductivity of SWCNT nanofluid which, shows 2-11.5% increment at a temperature 25° C. A model has been proposed to calculate the thermal conductivity of nanofluids and the results of proposed model show reasonably good agreement with available experimental data.