title: Heat Transfer Capability of (Ethylene Glycol + Water)-Based Nanofluids Containing Graphene Nanoplatelets: Design and Thermophysical Profile.
abstract: This research aims at studying the stability and thermophysical properties of nanofluids designed as dispersions of sulfonic acid-functionalized graphene nanoplatelets in an (ethylene glycol + water) mixture at (10:90)% mass ratio. Nanofluid preparation conditions were defined through a stability analysis based on zeta potential and dynamic light scattering (DLS) measurements. Thermal conductivity, dynamic viscosity, and density were experimentally measured in the temperature range from 283.15 to 343.15 K and nanoparticle mass concentrations of up to 0.50% by using a transient plate source, a rotational rheometer, and a vibrating-tube technique, respectively. Thermal conductivity enhancements reach up to 5% without a clear effect of temperature while rheological tests evidence a Newtonian behavior of the studied nanofluids. Different equations such as the Nan, Vogel-Fulcher-Tamman (VFT), or Maron-Pierce (MP) models were utilized to describe the temperature or nanoparticle concentration dependences of thermal conductivity and viscosity. Finally, different figures of merit based on the experimental values of thermophysical properties were also used to compare the heat transfer capability and pumping power between nanofluids and base fluid.
authors.affiliation: Departamento de Física Aplicada, Facultade de Ciencias, Universidade de Vigo, E-36310, Vigo, Spain. dacabaleiro@uvigo.es.
authors.forename: D
authors.identifier: http://orcid.org/0000-0003-2605-3664
authors.initials: D
authors.lastname: Cabaleiro
authors.affiliation: Istituto per le Tecnologie della Costruzione, Consiglio Nazionale delle Ricerche, Padova, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Colla
authors.affiliation: Istituto di Chimica della Materia Condensata e di Tecnologie per l'Energia, Consiglio Nazionale delle Ricerche, Padova, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Barison
authors.affiliation: Departamento de Física Aplicada, Facultade de Ciencias, Universidade de Vigo, E-36310, Vigo, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Lugo
authors.affiliation: Istituto per le Tecnologie della Costruzione, Consiglio Nazionale delle Ricerche, Padova, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Fedele
authors.affiliation: Istituto per le Tecnologie della Costruzione, Consiglio Nazionale delle Ricerche, Padova, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Bobbo
keywords: Dynamic viscosity; Ethylene glycol + water; Graphene nanoplatelets; Heat transfer capability; Nanofluid; Pumping power; Thermal conductivity; Volumetric behavior