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Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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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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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.
K. Sathyanarayana, Donald M. Ogden
Nuclear Technology | Volume 92 | Number 2 | November 1990 | Pages 194-203
Technical Paper | Nuclear Safety | doi.org/10.13182/NT90-A34470
Articles are hosted by Taylor and Francis Online.
A modified version of the RELAP5/MOD2 thermal-hydraulic computer code is used to perform anticipated transient without scram (ATWS) calculations for the N Reactor. The ATWS calculations are performed for a spectrum of transients to determine the accident end state in support of the Level 2/3 probabilistic risk assessment. The predicted N Reactor response to a most severe, but highly unlikely accident, due to the postulated double-ended guillotine break of the cold-leg manifold combined with the failure of scram systems, is described. The calculated core melt frequency for the N Reactor due to such an event is <10−10/yr. The transient response for this event is predicted using a single-loop, eight-level core RELAP5/ MOD2 model of the N Reactor. The reactor power behavior is modeled using point-reactor kinetics. The kinetics model includes the contributions to the reactivity from the feedback effects of core void, fuel, graphite, and water temperature variations. To verify the basic response of the model, the RELAP5 analysis results for the scram transient are compared with a twodimensional neutronics code (TWIGL) calculation. The excess reactivity results for the loss-of-coolant accident, combined with simultaneous failure of scram systems, compare favorably with three-dimensional neutronics code (3DN) computations. The analysis also shows that the fuel temperatures during the transient have increased sufficiently in the top 30% of the core leading to fuel failure. The fuel temperatures are predicted assuming a constant power profile. However, the neutronics code calculations show that the normalized power varies from 100% at the core bottom to <5% at the top for 50% voided core. Therefore, the analysis provides a very conservative estimate of fuel temperatures for the transient.
