| Abstrakt: |
Enhancing heat transfer efficiency in thermal systems is a critical area of research. One promising approach to improving heat transfer rates is the incorporation of nanoparticles into the circulating fluid, though this can impact pressure drop characteristics. In this study, a novel graphene oxide-silica (GO(SiO₂)) nanohybrid was synthesized using sol–gel methods, combining the high thermal conductivity of graphene oxide with the dispersion stability of silica to address common limitations in nanofluid stability and thermal performance. Characterization via FTIR, XRD, and SEM revealed that SiO₂ successfully coated the surface of the GO, which was produced via a modified Hummers' method. The thermal and hydrodynamic performance of a GO(SiO₂)/water nanofluid at mass concentrations of 0.05%, 0.1%, 0.15%, and 0.2% were then investigated. The nanofluid was circulated through a helical pipe under predetermined heat flux conditions and at different Reynolds numbers (4000–9500). Thermal properties were evaluated by calculating the Nusselt number (Nu), the convective heat transfer coefficient (ℎ), and the heat transfer enhancement (HTE). Notably, the Nusselt number exhibited a remarkable increase of 78% at a 2.5 l/min flow rate, demonstrating the significant potential of the GO(SiO₂) nanohybrid for enhancing heat transfer efficiency in thermal systems. Additionally, pressure drop was analyzed using the friction coefficient and drag reduction percentage (DR%), with the maximum DR% of 11.4% occurring at the lowest Reynolds number and concentration. [ABSTRACT FROM AUTHOR] |
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