Studies on thermophysical property variations of graphene nanoparticle suspended ethylene glycol/water

Abstract

The objective of the study is to determine the thermophysical property variations (such as viscosity, density, specific heat capacity and thermal conductivity) of graphene suspended base fluid (ethylene glycol (EG)/water (W)), with respect to graphene nanoparticle concentration and hot fluid inlet temperature. Graphene nanoparticle concentrations (0.2, 0.4, 0.6, 0.8 and 1 vol.%) and the base fluid of 30:70 vol.% of EG: Water is prepared initially. The impact of graphene nanoparticle addition on base fluids based on experimentation in the commercial plate heat exchanger was studied. In this experiment, the hot fluid inlet temperature was varied at 55, 65 and 75 ?C. The experimental results of thermophysical properties were compared with the selected models proposed in the literature. Einstein (1956), Kitano (1981) and Bachelor models (1977) have been used to consider the effect of viscosity. The measured density and specific heat capacity were validated with Pak and Cho and Xuan models, respectively. To consider the effect of thermal conductivity, three different models (Maxwell (1954), Vajjah (2010) and Sahoo (2012)) have been used. Study revealed that the thermophysical properties of base fluid significantly affect the graphene nanoparticle suspension.