A new relationship on transport properties of nanofluids. Evidence with novel magnesium oxide based n-tetradecane nanodispersions

The worldwide increasing of thermal energy consumption fosters new technological solutions based on nanomaterials. The use of nanofluids enhances energy efficiency leading to eco-friendlier devices. Thus, researchers are encouraged to understand how modified thermophysical properties improve heat transfer capability. Magnesium oxide based n-tetradecane nanofluids are designed in terms of stability for cold storage application. Thermal conductivity, viscosity, density, and isobaric heat capacity were determined by transient hot wire, rotational rheometry, mechanical oscillation U-tube, and differential scanning calorimetry. Furthermore, a useful relationship on thermal conductivity and viscosity of nanofluids is proposed based on Andrade, Osida and Mohanty theories. Its reliability is checked with the here reported results and literature data of different nanofluids: titanium oxide within water, silver within poly(ethylene glycol), and aluminium oxide within (1-ethyl-3methylimidazolium methanesulfonate + water). Similar trends have been found for all nanofluids excepting titanium oxide aqueous nanofluids, this differentiated behaviour being expected by the proposed relationship.(c) 2021 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

The use of nanomaterials in addressing the global issue of thermal energy consumption has proven to be effective in improving energy efficiency and promoting eco-friendly devices. This study focuses on magnesium oxide-based nanofluids designed for cold storage applications, examining the impact of modified thermophysical properties on heat transfer capability. Experimental measurements of thermal conductivity, viscosity, density, and isobaric heat capacity were conducted, and a relationship between the thermal conductivity and viscosity of nanofluids was proposed and validated.