Thermal properties of ethylene glycol-carbon based nano-fluids

We present results of thermal conductivity, thermal diffusivity, and specific heat of Ethylene Glycol (EG)-Carbon nano-fluids obtained using Thermal Constants Analyser (TPS 2200). A two-step method including a magnetic stirrer and an ultrasonic device was used to prepare stable EG-Carbon nano-fluids. Carbon nanoparticles were dispersed slowly in EG with different concentrations of 1 wt%, 2 wt%, 3 wt%, and 4 wt%. Thermal coefficients of the prepared nano-fluids at each concentration were measured at temperatures 10, 20, 30, 40, 50, and 60 °C. The percentage increment in thermal conductivity increases with concentration, as is evident from the observed increments of 20% and 31% for 1 wt% and 4 wt% concentration at 10 ℃, respectively. The highest increase in thermal diffusivity of about 32% was observed when the loading of carbon nanoparticles was increased from 1 wt% to 4 wt% at 10 °C. On the other hand, the same increment in concentration at 10 °C led to a decrease of 15% in specific heat.