0
Research Papers: Evaporation, Boiling, and Condensation

Boiling Performance of Graphene Oxide Coated Copper Surfaces at High Pressures

[+] Author and Article Information
Nanxi Li

Mem. ASME
Mechanical Engineering Department,
Kansas State University,
3002 Rathbone Hall,
Manhattan, KS 66506
e-mail: nli@ksu.edu

Amy Rachel Betz

Mem. ASME
Mechanical Engineering Department,
Kansas State University,
3002 Rathbone Hall,
Manhattan, KS 66506
e-mail: arbetz@ksu.edu

1Corresponding author.

Contributed by the Heat Transfer Division of ASME for publication in the JOURNAL OF HEAT TRANSFER. Manuscript received October 7, 2016; final manuscript received January 20, 2017; published online June 21, 2017. Assoc. Editor: Satish G. Kandlikar.

J. Heat Transfer 139(11), 111504 (Jun 21, 2017) (6 pages) Paper No: HT-16-1639; doi: 10.1115/1.4036678 History: Received October 07, 2016; Revised January 20, 2017

Graphene has been investigated due to its mechanical, optical, and electrical properties. Graphene's effect on the heat transfer coefficient (HTC) and critical heat flux (CHF) in boiling applications has also been studied because of its unique structure and properties. Methods for coating graphene oxide (GO) now include spin, spray, and dip coating. In this work, graphene oxide coatings are spray coated on to a copper surface to investigate the effect of pressure on pool boiling performance. For example, at a heat flux of 30 W/cm2, the HTC increase of the GO-coated surface was 126.8% at atmospheric pressure and 51.5% at 45 psig (308 kPa). For both surfaces, the HTC increases with increasing pressure. However, the rate of increase is not the same for both surfaces. Observations of bubble departure showed that bubbles departing from the graphene oxide surface were significantly smaller than that of the copper surface even though the contact angle was similar. The change in bubble departure diameter is due to pinning from micro- and nanostructures in the graphene oxide coating or nonhomogeneous wettability. Condensation experiments at 40% relative humidity on both the plain copper surface and the graphene oxide coated surface show that water droplets forming on both surfaces are significantly different in size and shape despite the similar contact angle of the two surfaces.

FIGURES IN THIS ARTICLE
<>
Copyright © 2017 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

Effect of pressure on specific volume and enthalpy of water

Grahic Jump Location
Fig. 2

Schematic picture of the boiling vessel: 1—pressure transducer, 2—nitrogen inlet, 3—thermocouple, 4—viewing port, 5—PTFE insulation, 6—copper rod, 7—cartridge heater, 8—nitrogen outlet, 9—bolt, 10—flange and flange cap, and 11—bulk cartridge heater

Grahic Jump Location
Fig. 3

Schematic design of the heated surface block

Grahic Jump Location
Fig. 4

(a) Topography of plain copper surface, (b) 3D image of plain copper surface at 2500×, (c) topography of GO-coated surface, and (d) 3D image of GO-coated surface at 2500×, and (e) side-view of the graphene oxide coating on the copper substrate

Grahic Jump Location
Fig. 9

Condensed water droplets on (a) plain copper surface and (b) graphene oxide coated surface

Grahic Jump Location
Fig. 8

Image of the graphene oxide coated surface after boiling

Grahic Jump Location
Fig. 7

Images of bubble forming at 0 psig (101 kPa), 30 W/cm2: (a) on a GO-coated surface plain copper surface and (b) on a plain copper surface

Grahic Jump Location
Fig. 6

HTC as a function of heat flux of water on both surfaces at different pressures

Grahic Jump Location
Fig. 5

Boiling curves of water on both surfaces at different pressures

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In