Experimental investigations of stability, density, thermal conductivity, and electrical conductivity of solar glycol-amine-functionalized graphene and MWCNT-based hybrid nanofluids

This research article discusses properties such as density, thermal conductivity, and electrical conductivity of solar glycol with aminc-functionalized graphene and multi-walled carbon nanotubes (MWCNTs). The hybrid nanofluid is prepared by dispersing the amine-functionalized graphene (AFG) and MWCNTs (50:50 in % by weight ratio) in pure solar glycol. The AFG and MWCNTs are dispersed in different volume concentrations of 0.05%, 0.1%, and 0.15% through the classical two-step homogenizing technique. Good colloidal stability nanofluid are prepared with Gum Arabic (non-covalent) as the surfactant. The stability of nanofluids is ensured through scanning electron microscopy, UV-Vis spectrometer, and zeta potential analyzer. The nanofluid thermal conductivity is measured with varying the nanomaterial loading from 0.05 to 0.15 vol% using a KD2 pro thermal analyzer. The thermal conductivity and electrical conductivity of nanofluid augmentations are considerably with an increasing volume concentration of AFG and MWCNT loading. The thermal conductivity of the AFG-MWCNT-based hybrid nanofluid is augmented by 8.59% for the maximum concentration of 0.15 vol% at 50 degrees C. The electrical conductivity of the solar glycol-based nanofluids is enhanced linearly with increased operating temperatures. The maximum electrical conductivity enhancement attained is similar to 28.85% at a nanoparticle loading of 0.15 vol% and 70 degrees C.

Automated summary

This study investigates the properties of thermal conductivity and electrical conductivity of a hybrid nanofluid using amine-functionalized graphene and multi-walled carbon nanotubes dispersed in solar glycol. The results show that both the thermal and electrical conductivity of the nanofluid increase with higher volume concentrations of the nanomaterials, indicating potential enhancements in heat transfer performance.