Nitrogen Heat Pipe for Cryocooler Thermal Shunt

  • F. C. Prenger
  • D. D. Hill
  • D. E. Daney
  • M. A. Daugherty
  • G. F. Green
  • E. W. Roth
Part of the A Cryogenic Engineering Conference Publication book series (ACRE, volume 41)

Abstract

A nitrogen heat pipe was designed, built and tested for the purpose of providing a thermal shunt between the two stages of a Gifford-McMahan (GM) cryocooler during cooldown. The nitrogen heat pipe has an operating temperature range between 63 and 123 K. While the heat pipe is in this temperature range during the system cooldown, it acts as a thermal shunt between the first and second stage of the cryocooler. The heat pipe increases the heat transfer to the first stage of the cryocooler, thereby reducing the cooldown time of the system. When the heat pipe temperature drops below the triple point, the nitrogen working fluid freezes, effectively stopping the heat pipe operation. A small heat leak between cryocooler stages remains because of axial conduction along the heat pipe wall. As long as the heat pipe remains below 63 K, the heat pipe remains inactive. Heat pipe performance limits were measured and the optimum fluid charge was determined.

Keywords

Heat Pipe Liquid Fraction Heat Leak Axial Conduction Fill Charge 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Plenum Press, New York 1996

Authors and Affiliations

  • F. C. Prenger
    • 1
  • D. D. Hill
    • 1
  • D. E. Daney
    • 1
  • M. A. Daugherty
    • 1
  • G. F. Green
    • 2
  • E. W. Roth
    • 2
  1. 1.Los Alamos National LaboratoryLos AlamosUSA
  2. 2.Naval Surface Warfare CenterAnnapolisUSA

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