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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Fusion Science and Technology
Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Takashi Mutoh, Ryuhei Kumazawa, Tetsuo Seki, Fujio Simpo, Goro Nomura, Tsuyoshi Ido, Tetsuo Watari, Jean-Marie Noterdaeme, Yanping Zhao
Fusion Science and Technology | Volume 35 | Number 3 | May 1999 | Pages 297-308
Technical Paper | doi.org/10.13182/FST35-297
Articles are hosted by Taylor and Francis Online.
Steady-state ion cyclotron range of frequency (ICRF) heating technologies have been developed to heat plasma for >30 min in the Large Helical Device (LHD). Steady-state-operation tests of high voltages up to 40 kV0p for >30 min were carried out on radio-frequency (rf) vacuum feedthroughs and a coaxial transmission line in a test set. Four types of ceramic feedthroughs, each having a 240-mm diameter, were tested. Cone-type alumina ceramic and cylinder-type silicon nitride composite-ceramic feedthroughs produced good performances of 40 kV/30 min and 50 kV/10 s. The others had vacuum leaks when subjected to long-pulse duration. The temperature of the cone-type alumina ceramic feedthrough was measured during the ICRF operations. By using gas-cooling techniques, the temperature increase of the ceramic was substantially reduced and saturated within 20 min. Without any gas-cooling techniques, the temperature increased linearly and did not saturate. Therefore, this approach could not be used for steady-state operation. The rf dissipation on the ceramic was calculated using the ANSYS finite element computer code. It was found that damaged feedthroughs had local high heat spots, which could result in vacuum leaks. A 240-mm-diam water-cooled coaxial transmission line was designed and tested for steady-state operation. Specially designed connector components and Teflon insulator disks were tested. During the test operation, the insulation gases of nitrogen, sulfur hexafluoride, and carbon dioxide were used to compare their insulation capabilities for steady state. For the duration of a 10-s pulse, these gases performed well up to 60 kV0p. However, for steady-state operation, carbon dioxide gas could not withstand voltages >40 kV0p. The connector components of the transmission line performed without problems below 50 kV0p and 1 kA0p for 30-min steady-state operation. The performance of the feedthroughs and transmission line exceeded the specifications for steady-state heating in the LHD.