Synthesis and Experimental Study of the Effect of Volume Fraction and Temperature on Thermal Conductivity Coefficient of Copper Oxide-Water Nanofluid

Abstract

The effect of volume fraction and temperature on the thermal conductivity coefficient of nanofluid copper oxide was investigated. The synthesized copper oxide nanoparticles were characterized by XRD, EDX and SEM. XRD analysis of the samples established the phase, EDX analysis provided the presence of copper and oxygen elements and SEM analysis confirmed their nanometer sizes. Copper oxide nanoparticles with dimensions of 50nm were used to synthesize copper oxide nanofluids. Copper oxide nanofluid were synthesized by two step method using distilled water as a base fluid in various volume fractions (%1, %2, %3). Then, they were mixed in ultrasonic for 30min and the nanoparticles were suspended homogeneously in the base fluid. In this regard, the pH of all samples was measured and controlled. Also, the thermal conductivity coefficient of the synthesized nanofluid samples were measured at temperature range . The results of the research showed that with increasing temperature and volume fraction of copper oxide nanoparticles in distilled water, the thermal conductivity coefficient in all samples increased. A sample with concentration of %3 had the higher thermal conductivity coefficient and optimum point in the concentrations, because in addition to the high thermal conductivity, it had a neutral pH. Finally, the experimental results of thermal conductivity of copper oxide nanofluids were compared to the obtained values from theoretical models.