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Synthesis of Graphene Nanofluids with Controllable Flake Size Distributions
Published on: July 17, 2019
Enhanced convective heat transfer using graphene dispersed nanofluids
Tessy Theres Baby1, Sundara Ramaprabhu
1Alternative Energy and Nanotechnology Laboratory (AENL), Nano Functional Materials Technology Centre (NFMTC), Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India. ramp@iitm.ac.in.
Nanoscale Research Letters
|June 30, 2011
Summary
Hydrogen exfoliated graphene (HEG) enhanced thermal conductivity in deionized water and ethylene glycol nanofluids. These advanced nanofluids show significant improvements in heat transfer properties for cooling applications.
Area of Science:
- Materials Science
- Nanotechnology
- Heat Transfer
Background:
- Nanofluids offer broad applications in electronics and cooling industries.
- Graphene-based nanofluids are of particular interest due to their unique properties.
Purpose of the Study:
- To develop and investigate the thermal properties of hydrogen exfoliated graphene (HEG) dispersed in deionized water (DI) and ethylene glycol (EG) based nanofluids.
- To evaluate the heat transfer performance enhancement offered by these nanofluids.
Main Methods:
- Hydrogen exfoliated graphene (HEG) synthesized via graphite oxide exfoliation.
- Functionalized HEG (f-HEG) dispersed in DI water and EG without surfactants.
- Characterization using XRD, electron microscopy, Raman, and FTIR spectroscopy.
- Measurement of thermal and electrical conductivities at various volume fractions and temperatures.
Main Results:
- A 0.05% volume fraction of f-HEG in DI water showed a 16% thermal conductivity enhancement at 25°C and 75% at 50°C.
- Nanofluids exhibited enhanced heat transfer properties, with Nusselt number increases exceeding thermal conductivity improvements.
- Electrical conductivity was also measured for different volume fractions and temperatures.
Conclusions:
- Functionalized HEG can significantly enhance the thermal conductivity and heat transfer performance of DI water and EG based nanofluids.
- These HEG-based nanofluids show great potential for advanced cooling applications in the electronics industry.
- The study demonstrates a surfactant-free method for preparing stable and effective graphene nanofluids.
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