Cryocoolers 8 pp 637-646 | Cite as

Development of a Magnetic Refrigerator Operating between 2 K and 10 K

  • A. Kashani
  • B. P. M. Helvensteijn
  • F. J. McCormack
  • A. L. Spivak
  • P. Kittel

Abstract

A prototype adiabatic demagnetization refrigerator (ADR) operating between 2 K and 10 K has been built and tested. The refrigerant for the ADR is Gadolinium Gallium Garnet (GGG). In the design thick slices of single-crystal GGG are sandwiched together with strips of high-purity copper. The copper strips are used to transfer heat between the GGG and the 2 K and the 10 K heat switches. The heat switches employed in the ADR have no moving parts. The 10 K heat switch is a helium gas-gap heat switch; while, the 2 K heat switch is a He II-gap heat switch. Preliminary tests indicate that the prototype ADR can provide 27 mW of cooling at 2 K for 165 s; where, the cycle period is 12.6 minutes. The efficiency of the ADR relative to Carnot is 25%. Methods for improving the efficiency of the system are discussed.

Keywords

Heat Sink Heat Load Heat Transfer Area Magnetic Refrigeration Heat Leak 
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

© Springer Science+Business Media New York 1995

Authors and Affiliations

  • A. Kashani
    • 1
  • B. P. M. Helvensteijn
    • 2
  • F. J. McCormack
    • 3
  • A. L. Spivak
    • 3
  • P. Kittel
    • 4
  1. 1.Atlas ScientificSunnyvaleUSA
  2. 2.Sterling Federal SystemsPalo AltoUSA
  3. 3.Trans-Bay ElectronicsRichmondUSA
  4. 4.NASA-Ames Research CenterMoffett FieldUSA

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