0
Research Papers: Evaporation, Boiling, and Condensation

Subcooled Pool Boiling Experiments on Horizontal Heaters Coated With Carbon Nanotubes

[+] Author and Article Information
V. Sathyamurthi, H-S. Ahn, D. Banerjee, S. C. Lau

Multiphase Flows and Heat Transfer Laboratory, Department of Mechanical Engineering, Texas A&M University, College Station, TX 77843-3123

J. Heat Transfer 131(7), 071501 (Apr 30, 2009) (10 pages) doi:10.1115/1.3000595 History: Received November 28, 2007; Revised September 09, 2008; Published April 30, 2009

Pool boiling experiments were conducted with three horizontal, flat, silicon surfaces, two of which were coated with vertically aligned multiwalled carbon nanotubes (MWCNTs). The two wafers were coated with MWCNT of two different thicknesses: 9μm (Type-A) and 25μm (Type-B). Experiments were conducted for the nucleate boiling and film boiling regimes for saturated and subcooled conditions with liquid subcooling of 030°C using a dielectric fluorocarbon liquid (PF-5060) as test fluid. The pool boiling heat flux data obtained from the bare silicon test surface were used as a base line for all heat transfer comparisons. Type-B MWCNT coatings enhanced the critical heat flux (CHF) in saturated nucleate boiling by 58%. The heat flux at the Leidenfrost point was enhanced by a maximum of 150% (i.e., 2.5 times) at 10°C subcooling. Type-A MWCNT enhanced the CHF in nucleate boiling by as much as 62%. Both Type-A MWCNT and bare silicon test surfaces showed similar heat transfer rates (within the bounds of experimental uncertainty) in film boiling. The Leidenfrost points on the boiling curve for Type-A MWCNT occurred at higher wall superheats. The percentage enhancements in the value of heat flux at the CHF condition decreased with an increase in liquid subcooling. However the enhancement in heat flux at the Leidenfrost points for the nanotube coated surfaces increased with liquid subcooling. Significantly higher bubble nucleation rates were observed for both nanotube coated surfaces.

FIGURES IN THIS ARTICLE
<>
Copyright © 2009 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 5

Pool boiling curves for different surfaces at low values of liquid subcooling

Grahic Jump Location
Figure 6

Pool boiling curves for different surfaces at high values of liquid subcooling

Grahic Jump Location
Figure 7

Schematic of the heat transfer mechanism for carbon nanotubes in film boiling: (a) Type-A (9 μm thickness), and (b) Type-B (25 μm thickness) MWCNT

Grahic Jump Location
Figure 1

Design of experimental apparatus: (a) test section in viewing chamber, (b) schematic of the heater apparatus (11,15)

Grahic Jump Location
Figure 2

Pool boiling curves for bare silicon surface at different values of liquid subcooling in nucleate and film boiling regimes

Grahic Jump Location
Figure 3

Pool boiling curves for silicon surface with Type-A (9 μm tall) MWCNT, for different values of liquid subcooling in nucleate and film boiling regimes

Grahic Jump Location
Figure 4

Pool boiling curves for boiling on silicon surface with Type-B (25 μm tall) MWCNT, for different values of liquid subcooling in nucleate and film boiling regimes

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