Graphene-Based Nanofluids: Production Parameter Effects on Thermophysical Properties and Dispersion Stability.

Area of Science:

• Materials Science
• Nanotechnology
• Thermal Engineering

Background:

• Graphene-based nanofluids offer enhanced thermal properties but require careful fabrication for stability.
• Understanding thermophysical properties and dispersion stability is crucial for their practical application.

Purpose of the Study:

• To investigate the thermophysical properties and dispersion stability of graphene-based nanofluids.
• To determine the influence of fabrication temperature, graphene concentration, and surfactant ratio on nanofluid performance.

Main Methods:

• Characterization of graphene nanopowder (crystalline structure, size, morphology, elemental content).
• Suspension preparation at varying temperatures (10-70 °C) with different graphene and surfactant concentrations.
• Determination of thermophysical properties (density, specific heat capacity, viscosity, thermal conductivity) and physical stability.

Main Results:

• Nanofluid density decreased with increasing fabrication temperature.
• Specific heat capacity showed high sensitivity to graphene and surfactant concentrations, with up to a 28.12% reduction.
• Fabrication temperature was key for viscosity and thermal conductivity, yielding a ~4.9% viscosity reduction and ~125.72% thermal conductivity increase.
• A 1:1 weight ratio of graphene to surfactant ensured physical stability for 45 days.

Conclusions:

• Fabrication temperature is a critical parameter influencing graphene-based nanofluid viscosity and thermal conductivity.
• Optimized graphene-to-surfactant ratios are essential for achieving long-term dispersion stability.
• The findings support the use of these nanofluids in moderate-temperature thermal applications.