Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Heat Transfer above Liquid Helium Surface in Cryostat

극저온용기 액체헬륨 표면 상부의 열전달 특성

  • 최연석 (한국기초과학지원연구원 물성과학연구부) ;
  • 김동락 (한국기초과학지원연구원 물성과학연구부) ;
  • 신동원 (한국기초과학지원연구원 물성과학연구부)
  • Received : 2010.08.09
  • Accepted : 2011.01.03
  • Published : 2011.02.10
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Abstract

The cryogenic cooling load from the top plate of cryostat to liquid helium surface, including wall conduction, thermal radiation and current leads, is investigated in a closed cryostat system for superconducting magnet. In general methods of load estimation, individual load is calculated separately, however they are actually coupled each other because of natural convection of helium vapor. Using relevant heat transfer analysis, we calculate cryogenic load with taking into account the effect of natural convection. Cryogenic load is under-estimated approximately 1% when the natural convection is ignored. The difference between actual cooling load and cooling load by individual calculation increases with supplying current.

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References

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