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Title: RECENT PROGRESS IN DYNAMIC PROCESS SIMULATION OF CRYOGENIC REFRIGERATORS

Abstract

At the CEC 2005 a paper with the title 'Helium refrigerator design for pulsed heat load in Tokamaks' was presented. That paper highlighted the control requirements for cryogenic refrigerators to cope with the expected load variations of future nuclear fusion reactors. First dynamic computer simulations have been presented.In the mean time, the computer program is enhanced and a new series of process simulations are available. The new program considers not only the heat flows and the temperature variations within the heat exchangers, but also the variation of mass flows and pressure drops. The heat transfer numbers now are calculated in dependence of the flow speed and the gas properties. PI-controllers calculate the necessary position of specific valves for maintaining pressures, temperatures and the rotation speed of turbines.Still unsatisfactory is the fact, that changes in the process arrangement usually are attended by adjustments in the program code. It is the main objective of the next step of development a more flexible code which enables that any user defined process arrangements can be assembled by input data.

Authors:
 [1]
  1. Linde Kryotechnik AG, Dattlikonerstrasse 5, CH-8422 Pfungen (Switzerland)
Publication Date:
OSTI Identifier:
21136883
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 985; Journal Issue: 1; Conference: Cryogenic Engineering Conference - CEC: Advances in cryogenic engineering, Chattanooga, TN (United States), 16-20 Jul 2007; Other Information: DOI: 10.1063/1.2908680; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; COMPUTER CODES; COMPUTERIZED SIMULATION; CRYOGENICS; DESIGN; HEAT EXCHANGERS; HEAT FLUX; HEAT TRANSFER; HEATING LOAD; HELIUM; PRESSURE DROP; REFRIGERATORS; THERMONUCLEAR REACTORS; TOKAMAK DEVICES; VALVES; VARIATIONS

Citation Formats

Kuendig, A. RECENT PROGRESS IN DYNAMIC PROCESS SIMULATION OF CRYOGENIC REFRIGERATORS. United States: N. p., 2008. Web. doi:10.1063/1.2908680.
Kuendig, A. RECENT PROGRESS IN DYNAMIC PROCESS SIMULATION OF CRYOGENIC REFRIGERATORS. United States. doi:10.1063/1.2908680.
Kuendig, A. Sun . "RECENT PROGRESS IN DYNAMIC PROCESS SIMULATION OF CRYOGENIC REFRIGERATORS". United States. doi:10.1063/1.2908680.
@article{osti_21136883,
title = {RECENT PROGRESS IN DYNAMIC PROCESS SIMULATION OF CRYOGENIC REFRIGERATORS},
author = {Kuendig, A.},
abstractNote = {At the CEC 2005 a paper with the title 'Helium refrigerator design for pulsed heat load in Tokamaks' was presented. That paper highlighted the control requirements for cryogenic refrigerators to cope with the expected load variations of future nuclear fusion reactors. First dynamic computer simulations have been presented.In the mean time, the computer program is enhanced and a new series of process simulations are available. The new program considers not only the heat flows and the temperature variations within the heat exchangers, but also the variation of mass flows and pressure drops. The heat transfer numbers now are calculated in dependence of the flow speed and the gas properties. PI-controllers calculate the necessary position of specific valves for maintaining pressures, temperatures and the rotation speed of turbines.Still unsatisfactory is the fact, that changes in the process arrangement usually are attended by adjustments in the program code. It is the main objective of the next step of development a more flexible code which enables that any user defined process arrangements can be assembled by input data.},
doi = {10.1063/1.2908680},
journal = {AIP Conference Proceedings},
number = 1,
volume = 985,
place = {United States},
year = {Sun Mar 16 00:00:00 EDT 2008},
month = {Sun Mar 16 00:00:00 EDT 2008}
}
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