Thermal transfer in mixtures of ethylene glicol with carbon coated iron nanoparticles under the influence of a uniform magnetic field

•Thermal conductivity of ethylene glycol increases due to adding Fe nanoparticles.•Thermal conductivity is enhanced when the samples are under a magnetic field.•Non-coated Fe nanoparticles show superior enhancement in thermal conductivity.•Theoretical models show good agreement with the experimental results.

In this work, the study of the heat transfer enhancement induced by aligning iron nanoparticles in an ethylenglicol fluid matrix is presented. In particular the effect of the interface is studied by analyzing the cases in which the nanoparticles are coated with carbon and comparing with uncoated ones. Results indicate that the coating acts as a thermal barrier making thermal conductivity to decrease. Moreover, the magnetic field creates aligned columns that enhance the heat transfer. Effective models are used to determine the role of the coating as well as of the aligning of the nanoparticles.