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Investigations on Cross Flow Micro Heat Exchangers for Operation with Lhe

  • A. Hofmann
  • S. Wild
  • L. R. Oellrich
  • K. Schubert
Chapter
Part of the Advances in Cryogenic Engineering book series (ACRE, volume 39)

Abstract

Compact heat exchangers as being produced by new methods of micro technology1 are promising in conventional technique. Typically, with water, a power of 20 kW can be transferred with a 1 cm3 cross flow element. In order to get some experience on low temperature behaviour of such devices, we have tested two of such cross flow heat exchangers. The tests were done with an existing apparatus where the helium flow is driven by a thermomechanical pump. Heaters in both flow paths allow to adjust operational temperatures between 1.8 K and about 10K. One of the heat exchangers was made from a stack of finely machined Cu sheets of 0.1 mm thickness, and for comparison, also a stainless steel type was used. Their performances are analysed and compared with calculations.

Keywords

Heat Exchanger Outlet Temperature Cross Flow Heater Power Heat Rejection 
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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Copyright information

© Springer Science+Business Media New York 1994

Authors and Affiliations

  • A. Hofmann
    • 1
  • S. Wild
    • 3
  • L. R. Oellrich
    • 3
  • K. Schubert
    • 2
  1. 1.Kernforschungszentrum Karlsruhe, ITPKarlsruheGermany
  2. 2.HVTKarlsruheGermany
  3. 3.Inst. f. Techn. Thermodynamik und KältetechnikUniv. KarlsruheGermany

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