A Novel Scheme to Handle Highly Pulsed Loads with a Standard Helium Refrigerator

  • Don Slack
Part of the Advances in Cryogenic Engineering book series (ACRE, volume 39)


Helium refrigerator performance degrades rapidly when it has to handle a varying or pulsed heat load. A novel scheme is presented to handle highly pulsed 4.5 K cryogenic loads with a standard helium refrigerator by isolating it from these pulses. The scheme uses a relatively simple arrangement of control valves, heat exchangers, and a storage dewar. Applications include pulsed tokamak machines such as TPX (Tokamak Physics Experiment) and ITER (International Thermonuclear Experimental Reactor). For example, the TPX (currently in the conceptual design phase in a DoE contract) requires an average 4.5 K refrigerator capacity of about 10 kW; however, pulsed loads caused by eddy current and nuclear heating will exceed 100 kW. The scheme presented here provides a method for handling these pulsed loads. Because of the simple and proven nature of the components involved and the thermodynamic properties of the helium, the system could be implemented for projects such as TPX or ITER with little or no development.


Heat Exchanger Lawrence Livermore National Laboratory International Thermonuclear Experimental Reactor Pulse Load Condense Heat Transfer 
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Copyright information

© Springer Science+Business Media New York 1994

Authors and Affiliations

  • Don Slack
    • 1
  1. 1.Lawrence Livermore National LaboratoryUniversity of CaliforniaLivermoreUSA

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