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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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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.
K. N. Schwinkendorf
Nuclear Science and Engineering | Volume 132 | Number 1 | May 1999 | Pages 118-126
Technical Paper | doi.org/10.13182/NSE99-A2053
Articles are hosted by Taylor and Francis Online.
Severe accident simulation has been performed in the past to predict the energy release arising from hypothetical core disruptive accidents (CDA) postulated to occur in liquid-metal reactors (LMRs). This field has developed to a mature state with the creation of computer codes such as SIMMER, but these codes are highly specific to LMR designs. More recent attention has focused on thermal-spectrum criticality accidents. This has resulted in the creation of a new simulator code, A Transient History for Energetic Nuclear Accidents_2D (ATHENA_2D), which solves the transient multigroup space-time kinetics equations, coupled to multichannel thermal hydraulics and computational fluid dynamics. This paper presents results from two-dimensional kinetics simulations performed for a water reflood recriticality accident in a damaged light water reactor, typical of a Three Mile Island end-state core geometry. The accident is initiated by assuming reflood water that is insufficiently borated and a reactivity-optimized debris bed. Reactivity insertion rates analyzed in this study generally are smaller than in LMR CDAs (tens of dollars per second versus up to hundreds of dollars per second), and the energetics are slightly lower. Parametric variation of input was performed, including reactivity insertion rate and initial temperature.