Thermodynamics Research Center / ThermoML | Thermochimica Acta

Thermal conductivity enhancement of ethylene glycol and water with graphene nanoplatelets

Selvam, C., Lal, D. M.[D. Mohan], Harish, S.[Sivasankaran]
Thermochim. Acta 2016, 642, 32-38
ABSTRACT
In the present work, we report the effective thermal conductivity of ethylene glycol and water with graphene nanoplatelets. Sodium deoxycholate, a bile salt was used as the surfactant to prepare stable nanofluid dispersions. Stability tests were performed using UVCvis absorption spectrometry and zeta potential to monitor the stability of the prepared nanofluids as a function of time. Thermal conductivity measurements were carried out using transient hot wire technique. Thermal conductivity of the nanofluids significantly increases with respect to graphene loading. Maximum thermal conductivity enhancements of !less thanless than21% and !less thanless than16% at a loading of 0.5 vol% was obtained for the nanofluids with graphene nanoplatelets seeded in ethylene glycol and water respectively. Analysis of experimental results with Maxwell-Garnett type effective medium theory reveal that despite the high thermal conductivity of graphene, interfacial thermal resistance between graphene and the surrounding base fluid limits the thermal conductivity enhancement significantly. The interfacial thermal resistance between graphene sheet and ethylene glycol was found to be 2.2*10-8m2 KW-1 while between graphene sheet and water was found to be 1.5*10-8m2 KW-1 respectively for the present nanofluids.
Compounds
# Formula Name
1 C2H6O2 1,2-ethanediol
2 H2O water
3 C24H39NaO4 sodium deoxycholate
Datasets
The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type Compound-# Property Variable Constraint Phase Method #Points
  • POMD
  • 1
  • Thermal conductivity, W/m/K ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Hot wire method
  • 3
  • POMD
  • 2
  • Thermal conductivity, W/m/K ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Hot wire method
  • 3
  • POMD
  • 1
  • 3
  • Thermal conductivity, W/m/K ; Liquid
  • Mass fraction - 3; Liquid
  • Pressure, kPa; Liquid
  • Temperature, K; Liquid
  • Liquid
  • Hot wire method
  • 1
  • POMD
  • 3
  • 2
  • Thermal conductivity, W/m/K ; Liquid
  • Mass fraction - 3; Liquid
  • Pressure, kPa; Liquid
  • Temperature, K; Liquid
  • Liquid
  • Hot wire method
  • 1