The authors prepared a series of carbon nanotube (CNT) nanorefrigerants with varying size and amount of nanotubes to determine how these properties affect thermal conductivity. A TPS Instrument was used to measure thermal conductivity of the nanorefrigerants; R113 was used as a host nanorefrigerant. It was determined that higher concentrations of smaller diameter CNTs results in higher nanofrigerant thermal conductivity. A few theoretical models were also used to compare to ...
In this article, the authors look at and compare the different methods that can be used for the measurement of thermal conductivity of nanofluids. These methods include THW and TPS among other transient and steady-state methods. This was investigated due to the large differences in thermal conductivity that were being reported for the same nanofluid from different laboratories around the world. It was determined that the system/method used the ...
Using Al2O3 nanoparticles, de-ionized water, and different volume fractions of two surfactants, Al2O3/water nanofluids were prepared by a two-step method. Thermal conductivities of the nanofluids were measured by the thermal constants analyzer. The choice of surfactant used (either sodium dodecyl sulfate (SDS) or polyvinylpyrrolidone (PVP)) had an influence on the thermal and mechanical properties of the nanofluids. PVP was found to be better at stabilizing the nanofluid, ...
A series of Al2O3-water nanofluids were synthesized and their thermal conductivities were evaluated under different pH values and concentrations of surfactant (SDBS) using the Thermal Constants Analyzer. All the properties studied were found to have a strong effect on the measured thermal conductivity. By using the procedure listed in the report, the thermal conductivity of Al2O3-water nanofluids can be increased by 10% with the use of only 0.0015 ...
The addition of Cu nanoparticles to water was studied at different pH values and different dispersant concentrations by the measurement of zeta potential and absorbency. Thermal conductivity was measured. It was found that the ideal properties of the nanofluid were obtained at pH 9.5....
