Potential heat transfer enhancement of functionalized graphene nanoplatelet dispersions in a propylene glycol-water mixture. Thermophysical profile

摘要: Abstract The thermal conductivity of the heat transfer fluids commonly used in industrial processes is a major concern continuous searching their performance improvement. During last decades, dispersions high nanoparticles conventional fluids, nanofluids, have received increasingly attention to achieve this aim. thermophysical properties, not available literature, are necessary describe thermo-fluid behaviour. Thus, characterization studies become evaluate potential enhancements. This work presents profile according properties with noticeable influence on capability different functionalized graphene nanoplatelet (0.25, 0.50, 0.75 and 1.0) wt% propylene glycol-water mixture at (30:70)% mass ratio, usually employed facilities. Initially, nanofluid stability was investigated optimizing pH value by analysing zeta measurements. Then, densities, capacities, conductivities, dynamic viscosities were experimentally determined throughout temperature range from (293.15 323.15) K. Density studied using pycnometric technique results analyze isobaric expansivity A differential scanning calorimeter utilized obtain capacities conductivities measured for nanopowder, base fluid nanofluids through devices based guarded flow meter method transient hot wire technique. Furthermore, rheological behaviour analysed means rotational rheometer cone-plate geometry. Conductivity enhancements up 16% respect achieved. Finally, laminar turbulent an analysis figures merit experimental results.