Thermal Characteristics of Graphite Foam Thermosyphon for Electronics Cooling

  • Lim, Kyung-Bin (Department of Mechanical Engineering, Hanbat National University) ;
  • Roh, Hong-Koo (Department of Mechanical Engineering, Hanbat National University)
  • Published : 2005.10.01

Abstract

Graphite foams consist of a network of interconnected graphite ligaments and are beginning to be applied to thermal management of electronics. The thermal conductivity of the bulk graphite foam is similar to aluminum, but graphite foam has one-fifth the density of aluminum. This combination of high thermal conductivity and low density results in a specific thermal conductivity about five times higher than that of aluminum, allowing heat to rapidly propagate into the foam. This heat is spread out over the very large surface area within the foam, enabling large amounts of energy to be transferred with relatively low temperature difference. For the purpose of graphite foam thermosyphon design in electronics cooling, various effects such as graphite foam geometry, sub-cooling, working fluid effect, and liquid level were investigated in this study. The best thermal performance was achieved with the large graphite foam, working fluid with the lowest boiling point, a liquid level with the exact height of the graphite foam, and at the lowest sub-cooling temperature.

Keywords

References

  1. 3M, Accessed: April 5, 2002a, 'Fluorinert Electronic Liquid FC-72 Product Information,' Online : http://www.3m.com
  2. 3M, Accessed: April 5, 2002b, 'Fluorinert Electronic Liquid FC-87 Product Information,' Online: http://www.3m.com
  3. Garman, R. W., Elwell, R. J., Accessed: April 5, 2002, 'Thermal Performance of a Graphite Foam Material with Water Flow for Cooling Power Electronics,' Online: http://www.3m.com
  4. Gunther, S. H., Binns, F., Carmean, D. M. and Hall, J. C., 2001, 'Managing the Impact of Increasing Microprocessor Power Consumption,' Intel Technology Journal, Q1, pp. 1-9
  5. Jiang, Y. Y., Wang, W. C., Wang, D. and Wang, B. X., 2001, 'Boiling Heat Transfer on Machined Porous Surfaces with Structural Optimization,' Int. J. of Heat and Mass Transfer 44, pp. 443-456 https://doi.org/10.1016/S0017-9310(00)00057-0
  6. Kedzierski, 2002, M., Private Communication
  7. Klett, J. and Conway, B., 2000, 'Thermal Management Solutions Utilizing High Thermal Conductivity Graphite Foams,' Proceedings of the 45th International SAMPE Symposium and Exhibition, Long Beach, CA, May 21-25
  8. Klett, J., Klett, L., Burchell, T. and Walls, C., 2000, 'Graphitic Foam Thermal Management Materials for Electronic Packaging,' 00FCC-117 Society of Automotive Engineers
  9. MRI, Accessed: March 25, 2002, 'S-BondTM Joining Graphite Foams,' Online : http://www.pocofoam.com/Library/techdata.pdf
  10. Mudawar, I. and Anderson, T. M., 1989, 'High Flux Electronic Cooling by Means of Pool Boiling - Part I : Parametric Investigation of the Effects of Coolant Variation, Pressurization, Subcooling, and Surface Augmentation,' Heat Transfer in Electronics, ASME HTD-Vol. 111, Ed. R. K. Shah, pp. 25-34
  11. Mudawar, I. and Anderson, T. M., 1989, 'High Flux Electronic Cooling by Means of Pool Boiling - Part II : Optimization of Enhanced Surface Geometry,' Heat Transfer in Electronics, ASME HTD-Vol. 111, Ed. R. K. Shah, pp. 35-49
  12. Poco Graphite Foam, Accessed: March 25, 2002, 'Properties Data Sheet,' Online: http://www.pocofoam.com/Library/techdata.pdf
  13. Ramaswamy, C., Joshi, Y. and Nakayama, W., 2000, 'Combined Effects of Sub-Cooling and Operating Pressure on the Performance of a Two-Chamber Thermosyphon,' IEEE Transactions on Components and Packaging Technologies, pp. 61-69 https://doi.org/10.1109/6144.833043
  14. Ramaswamy, C., Joshi, Y., Nakayama, W. and Johnson, W. B., 2001, 'Thermal Performance of a Compact Two-phase Thermosyphon : Response to Evaporator Confinement and Transient Loads,' Enhanced Heat Transfer, 6, pp. 279-288 https://doi.org/10.1007/BF02931990
  15. Viswanath, R., Wakharkar, V., Watwe, A. and Lebonheur, V., 2000, 'Thermal Performance Challenges from Silicon to Systems,' Intel Technology Journal, Q3, pp. 1-16
  16. Wu, W., Du, J. -H., Hu, X. -J., Wang, B. -X., 2002, 'Pool Boiling Heat Transfer and Simplified One-dimensional Model for Prediction on Coated Porous Surfaces with Vapor Channels,' Int. J. of Heat and Mass Transfer 45, pp. 1117-1125 https://doi.org/10.1016/S0017-9310(01)00192-2