Exploiting the thermal and rheological potentials of graphene-PAG nanolubricant for the development of energy efficient refrigeration systems

Abstract

The addition of nanoparticles is one of state of the art methods to enhance the thermophysical and heat transfer characteristics of cooling and lubricating fluids. Exploring the energy-saving potentials of novel material graphene as a lubricant additive is the primary focus of this study. The thermal and rheological properties of Poly Alkylene glycol(PAG)-graphene nanolubricant at different volume fractions are investigated to pose as an energy-efficient alternative lubricant in refrigeration systems. Moreover, genetic algorithm based regression correlations are proposed to predict the thermal conductivity and viscosity of the graphene-PAG nanolubricant. The results show that the addition of graphene nanoplatelets to the oil has the potential to improve the thermophysical characteristics of the lubricant. The presence of platelet shaped nano graphene particles enhance the thermal and rheological characteristics of the colloidal suspension. The proposed regression models exhibit excellent agreement with the experimental data. Thermal and rheological studies revealed that the application of graphene-PAG nanolubricant is an option to improve the energy efficiency and overall performance of HVAC systems.