Research Papers: Porous Media

Heat Transfer in Porous Graphite Foams

[+] Author and Article Information
Brian E. Thompson

Dean of Engineering and Professor
A'Sharqiyah University,
P.O. Box 42,
Ibra 400, Oman
e-mail: bthompson@asu.edu.om

Contributed by the Heat Transfer Division of ASME for publication in the JOURNAL OF HEAT TRANSFER. Manuscript received July 9, 2013; final manuscript received October 27, 2013; published online December 19, 2013. Assoc. Editor: Andrey Kuznetsov.

J. Heat Transfer 136(3), 032602 (Dec 19, 2013) (7 pages) Paper No: HT-13-1342; doi: 10.1115/1.4025905 History: Received July 09, 2013; Revised October 27, 2013

Measured values of heat transfer and pressure loss are presented for a variety of porous graphite foams in subsonic turbulent airflow. These foams were developed over the last decade to find combinations of high conductivity, porosity, strength, and low density suitable for application to rapid cooling of electronics and to corrosionless heat-exchangers. Measured maxima in the thermal performance that is the ratio of heat transfer to pressure loss, were correlated the pore structure obtained from scanning electron microscopy, to show a linear dependence of thermal performance on the average diameter of interpore windows representative of the cross-sectional area through which cooling air flows. For the same heat transfer, measured pressure losses were reduced by over two orders of magnitude by increasing pore and window diameters. However, the best thermal performance of porous graphite foams that were strong enough for industrial application, had measured pressure losses that were more than an order of magnitude greater than losses in conventional finned heat exchangers.

Copyright © 2014 by ASME
Your Session has timed out. Please sign back in to continue.


Johnson, I., William, T., Choate, W. T., and Amber Davidson, A., 2008, “Waste Heat Recovery: Technology and Opportunities in US Industry,” US Department of Energy, Office of Energy Efficiency and Renewable Energy, Industrial Technologies Program.
Roos, C. J., 2009, “An Overview of Industrial Waste Heat Recovery Technologies for Moderate Temperatures Less Than 1000°F,” U.S. Department of Energy, Industrial Technologies Program, Report WSUEEP09-26.
DeFrees, J., Stuckey, R., and Foote, J., 2007, “Condensing Economizers,” ASHRAE J., 11, pp. 16–23.
Butcher, T., 2007, “Condensing Economizers,” Perry's Chemical Engineer's Handbook, 8th ed., McGraw-Hill, New York, p. 53.
Gallego, C. N., and Klett, W. J., 2003, “Carbon Foams for Thermal Management,” Carbon, 41, pp. 1461–1466. [CrossRef]
Sheil, B. J., Evans, R. B., and Watson, G. M., 1959, “Molten Salt-Graphite Compatibility Tests—Results of Physical and Chemical Measurements,” ORNL Report 59-8-133.
Jayman, Y., and Mohamad, A. A., 2007, “Enhanced Heat Transfer Using Porous Carbon Foam in Cross Flow,” ASME J. Heat Transfer, 129(6), pp. 735–742. [CrossRef]
Jamin, Y. L., and Mohamad, A. A., 2008, “Natural Convection Heat Transfer Enhancements From a Cylinder Using Porous Carbon Foam: Experimental Study,” ASME J. Heat Transfer, 130(12), p. 122502. [CrossRef]
Boomsma, K., and Poulikakos, D., 2002, “The Effects of Compression and Pore Size Variations on the Liquid Flow Characteristics in Metal Foams,” ASME J. Fluids Eng., 124, pp. 263–272. [CrossRef]
Calmidi, V. V., and Mahajan, R. L., 2000, “Forced Convection in High Porosity Metal Foams,” ASME J. Heat Transfer, 122, pp. 557–565. [CrossRef]
Straatman, A. G., Gallego, N. C., Yu, Q., and Thompson, B. E., 2007, “Forced Convection Heat Transfer and Hydraulic Losses in Graphitic Foam,” ASME J. Heat Transfer, 129, pp. 1237–1245. [CrossRef]
Boomsma, K., Poulikakos, D., and Zwick, F., 2003, “Metal Foams as Compact High Performance Heat Exchangers,” Mech. Mater., 35, pp. 1161–1176. [CrossRef]
Straatman, A. G., Gallego, N. C., Yu, Q., and Thompson, B. E., 2006, “Characterization of Porous Carbon Foam as a Material for Compact Recuperators,” Proceedings of ASME Turbo Expo, Barcelona, Spain.
Campagna, M., 2007, “Graphite Foam Heat Exchanger (Radiator) Test,” Caterpillar Inc., Oak Ridge National Laboratory, Final Report, Contract 40005339.
Klett, W. J., Hardy, R., Romine, E., Walls, C., and Burchell, T., 2000, “High-Thermal Conductivity, Mesophase-Pitch-Derived Carbon Foam: Effect of Precursor on Structure and Properties,” Carbon, 38, pp. 953–973. [CrossRef]
Contescu, C. I., Azad, S., Miller, D., Lance, M. J., Baker, F. S., and Burchell, T. D., 2008, “Practical Aspects for Characterizing Air Oxidation of Graphite,” J. Nucl. Mater., 381, pp. 15–24. [CrossRef]
Moormann, R., Hinssen, H. K., Krussenberg, A. K., Stauch, B., and Wu, C. H., 1994, “Investigation of Oxidation Resistance of Carbon First-Wall Liner Materials of Fusion Reactors,” J. Nucl. Mater., 212–215, pp. 1178–1182. [CrossRef]
Yu, Q., Thompson, B. E., and Straatman, A. G., 2006, “A Unit-Cube Based Model for Heat Transfer and Pressure Loss in Porous Carbon Foam,” ASME J. Heat Transfer, 128, pp. 352–360. [CrossRef]
Kaviany, M., 1995, Principles of Heat Transfer in Porous Media, Springer-Verlag, New York, p. 32.
Taylor, G. I., 1971, “A Model for the Boundary Condition of a Porous Material. Part 1,” J. Fluid Mech., 49, pp. 319–326. [CrossRef]
Antohe, B. V., Lage, J. L., Price, D. C., and Weber, R. M., 1997, “Experimental Determination of Permeability and Inertia Coefficients of Mechanically Compressed Aluminum Porous Matrices,” ASME J. Fluids Eng., 119, pp. 404–412. [CrossRef]
Alam, M. K., and Maruyama, B., 2004, “Thermal Conductivity of Graphitic Carbon Foams,” Exp. Heat Transfer, 17, pp. 227–241. [CrossRef]
DeJong, N. C., and Jacobi, A. M., 2003, “Heat Transfer and Pressure Drop for Flow Through Bounded Louvered-Fin Arrays,” Exp. Therm. Fluid Sci., 27, pp. 237–250. [CrossRef]


Grahic Jump Location
Fig. 1

Exhaust-to-water heat exchanger made with porous graphite foam

Grahic Jump Location
Fig. 2

Slotted element made with porous graphite foam bonded to copper tubes

Grahic Jump Location
Fig. 3

Porous graphite foam elements in a gas-to-gas heat exchanger

Grahic Jump Location
Fig. 4

Conductive and porous graphite foam

Grahic Jump Location
Fig. 5

Schematic diagram of the experimental apparatus

Grahic Jump Location
Fig. 6

Schematic diagram of the flow configuration

Grahic Jump Location
Fig. 7

Structures of porous graphite foam. (a) Specimen 2A, (b) Specimen 3A, (c) Specimen 3B, (d) Specimen 3C, (e) Specimen 4A, (f) Specimen 4B, and (g) Specimen 4C.

Grahic Jump Location
Fig. 8

Average Nusselt number versus Reynolds number based on bulk flow velocity. Symbols correspond to the three best specimens (A, B, C) from four generations (1, 2, 3, and 4) of trial-and-error development of thermal foams.

Grahic Jump Location
Fig. 9

Pressure loss in height of water column (@ 20 °C) per unit length of foam in the streamwise direction versus Reynolds number based on bulk velocity. Symbols correspond to those shown on Fig. 8.

Grahic Jump Location
Fig. 10

Average Nusselt number versus pressure loss in height of water column (@ 20 °C) per unit length of foam in the streamwise direction. Symbols correspond to those shown on Fig. 8.

Grahic Jump Location
Fig. 11

Average convective heat transfer versus pressure losses in the streamwise direction. Symbols correspond to those shown on Fig. 8.

Grahic Jump Location
Fig. 12

Average convective heat transfer versus pressure losses in the streamwise direction for the specimens shown on Fig. 7. Symbols correspond to those shown on Fig. 8.

Grahic Jump Location
Fig. 13

Maximum measured thermal performance for specimens compared to the average diameter of interpore windows and pore diameter




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