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Title: Thulium-170 heat source

An isotopic heat source is formed using stacks of thin individual layers of a refractory isotopic fuel, preferably thulium oxide, alternating with layers of a low atomic weight diluent, preferably graphite. The graphite serves several functions: to act as a moderator during neutron irradiation, to minimize bremsstrahlung radiation, and to facilitate heat transfer. The fuel stacks are inserted into a heat block, which is encased in a sealed, insulated and shielded structural container. Heat pipes are inserted in the heat block and contain a working fluid. The heat pipe working fluid transfers heat from the heat block to a heat exchanger for power conversion. Single phase gas pressure controls the flow of the working fluid for maximum heat exchange and to provide passive cooling.
 [1] ;  [2] ;  [3]
  1. (Pleasanton, CA)
  2. (Livermore, CA)
  3. (Tracy, CA)
Publication Date:
OSTI Identifier:
Report Number(s):
US 5082617
DOE Contract Number:
Resource Type:
Research Org:
Lawrence Livermore National Laboratory (LLNL), Livermore, CA
Country of Publication:
United States
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