Enhancing Thermal Properties: A Comprehensive Study on Cellulose Nanocrystal Nanofluids

Nanofluids, characterized by a base fluid infused with nanoparticles, have gained substantial interest due to their superior thermal properties, primarily enhanced heat transfer capabilities. This study investigates the dispersion of cellulose nanocrystal (CNC) nanoparticles in base fluid and its subsequent impact on thermal properties. CNC nanoparticles obtained from Blue Goose Biorefineries Inc. were dispersed in distilled water and ethylene glycol (EG) at varying volume concentrations (0.25%,0.50%,0.75%). The prepared nanofluids underwent thorough stability analyses utilizing techniques such as ultrasonication. The CNC nanofluids ' thermal conductivity, density, viscosity, and specific heat capacity were systematically measured using instrumentation. The study found that adding cellulose nanocrystal (CNC) nanoparticles to an 80:20 water-ethylene glycol mixture significantly improves the thermal conductivity, viscosity, and density of the base fluid. Thermal conductivity increased linearly with higher CNC concentrations (0.25%, 0.5%, 0.75%) and temperatures (25-55 °C), peaking at 0.815 W/m·K at 55 °C with 0.75% CNC. Viscosity decreased with temperature but increased with higher CNC concentrations. Density also increased with CNC concentration and decreased with temperature, while specific heat capacity showed minimal changes with concentration but a slight increase with temperature. These enhancements make CNC nanofluids beneficial for heat transfer applications.