Graphene-Based Nanofluids: Production Parameter Effects on Thermophysical Properties and Dispersion Stability.

Naser Ali

doi:10.3390/nano12030357

Abstract

In this study, the thermophysical properties and dispersion stability of graphene-based nanofluids were investigated. This was conducted to determine the influence of fabrication temperature, nanomaterial concentration, and surfactant ratio on the suspension effective properties and stability condition. First, the nanopowder was characterized in terms of crystalline structure and size, morphology, and elemental content. Next, the suspensions were produced at 10 °C to 70 °C using different concentrations of surfactants and nanomaterials. Then, the thermophysical properties and physical stability of the nanofluids were determined. The density of the prepared nanofluids was found to be higher than their base fluid, but this property showed a decrease with the increase in fabrication temperature. Moreover, the specific heat capacity showed very high sensitivity toward the graphene and surfactant concentrations, where 28.12% reduction in the property was achieved. Furthermore, the preparation temperature was shown to be the primary parameter that effects the nanofluid viscosity and thermal conductivity, causing a maximum reduction of ~4.9% in viscosity and ~125.72% increase in thermal conductivity. As for the surfactant, using low concentration demonstrated a short-term stabilization capability, whereas a 1:1 weight ratio of graphene to surfactant and higher caused the dispersion to be physically stable for 45 consecutive days. The findings of this work are believed to be beneficial for further research investigations on thermal applications of moderate temperatures.

Highlights

IntroductionResearchers have focused on continuously enhancing the thermal performance of heat exchangers (HEs) to reduce their overall consumption of energy as well as minimize the size of their designs
Academic Editor: Zhifeng HaoFor many years, researchers have focused on continuously enhancing the thermal performance of heat exchangers (HEs) to reduce their overall consumption of energy as well as minimize the size of their designs
In the X-ray ray diffraction (XRD) characterization conducted on the obtained commercial graphene nanoplatelets, the electromagnetic beam that generates from the X-ray source is reflected from the crystalline plane

Summary

Introduction

Researchers have focused on continuously enhancing the thermal performance of heat exchangers (HEs) to reduce their overall consumption of energy as well as minimize the size of their designs. This is because these systems have major roles in our everyday lives, where their uses have ranged from domestic boilers up to industrial scale power generation [1]. One of the most successful approaches to accomplish this is through investigating the use of advanced working fluids than those conventionally used [2].

Methods

Results

Conclusion