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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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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.
A. H. Kazi
Nuclear Science and Engineering | Volume 60 | Number 1 | May 1976 | Pages 62-73
Technical Paper | doi.org/10.13182/NSE76-A26858
Articles are hosted by Taylor and Francis Online.
The Army Pulse Radiation Facility Reactor has been pulsed to 17 cents above prompt criticality using external reflector control. This is a novel method of fast-pulse reactor operation. The purpose of this work is to provide a high neutron fluence uniform over a 106-mm-diam, 198-mm-high in-core irradiation cavity or “glory hole,” in both pulse and steady-state modes of operation. The 106-mm-diam glory hole is obtained by removing from the standard core a cylindrical center fuel element, the “safety block,” and replacing it functionally by three 50.8-mm-thick, 305-mm-high scramable copper reflectors positioned 5.3 mm from the reactor shroud. The cost of this modification was favorable since fabrication of new fuel pieces was unnecessary. To date this assembly has been successfully pulsed to yields as high as 1.83 × 1017 fission/pulse. There is an ∼38% increase in prompt neutron lifetime in the reflected core due to the central cavity and the reflectors. The prompt negative shutdown coefficient is decreased only slightly so that the reflected core can be pulsed with requisite safety and satisfactory reproducibility. At the routine pulse level of 1.5 × 1017 (±2%) fissions, the pulse width is 66 µsec, the neutron fluence in the glory hole is 5.0 × 1014 n/cm2 (>10 keV), where the peak neutron flux is 6.4 × 1018 n/(cm2 sec) and the gamma-ray dose is 1.6 × 105 R. With a thermal-neutron flux trap, the peak thermal-neutron flux is 1 × 1018 n/(cm2 sec). With a neutron-to-gamma-ray converter, the peak gamma-ray emission rate is 3 × 109 R/sec. Operation at 10 kW in a steady-state mode produces a neutron flux (>10 keV) of 1012 n/(cm2 sec). Experiments have been performed previously to evaluate the use of reflectors as control and pulse rods. The present method of operation extends the use of reflectors to provide the principal mechanical shutdown mechanism in superprompt critical pulse operation.