(135a) Application of Novel Porous Graphene Nanoplatelets Composites for Enhanced Heat Transfer Properties
AIChE Annual Meeting
2018
2018 AIChE Annual Meeting
Nanoscale Science and Engineering Forum
Carbon Nanomaterials Graduate Student Award Session
Monday, October 29, 2018 - 12:30pm to 12:47pm
We investigated carbon nanotubes, multilayered chemical vapor deposited graphene/graphene oxide, and graphene nanoplatelets (GNP) coatings and achieved higher pool boiling performance with graphene nanoplatelets (GNP), however, the GNP coatings did not sustain the repetitive pool boiling tests making them ineffective for industrial applications. To overcome this, we developed novel copper-GNP (Cu-GNP) porous coatings by a multistep electrodeposition technique owing to higher thermal properties of copper particles.
Hierarchal porous surfaces with diverse morphologies were obtained by varying the electrodeposition process parameters and the concentration of GNP in the composites which were confirmed by scanning electron microscope (SEM). The rendered surfaces were hydrophilic in nature possessing higher wickability. The durability of the coatings was confirmed using the repetitive pool boiling studies. The composite coating with 2% GNP (weight/volume) produced a very high CHF of 286 W/cm² and HTC of 204 kW/m²-°C, representing an improvement of 130% in CHF and 290% in HTC compared to pristine copper surface. The proposed mechanism of enhanced heat transfer properties is attributed to the surface pores that serve as nucleation sites for additional bubble formation that depart in upward direction creating a turbulent convection that further improves the heat transfer rate.