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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.
Meeting Spotlight
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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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.
Rui Hu, Mujid S. Kazimi
Nuclear Technology | Volume 177 | Number 1 | January 2012 | Pages 8-28
Technical Paper | Fission Reactors | doi.org/10.13182/NT12-A13324
Articles are hosted by Taylor and Francis Online.
The TRACE/PARCS code was applied in this work to examine the validity of the coupled three-dimensional thermal-hydraulics and neutronics system analysis codes for boiling water reactor stability analysis. The evaluation was performed against the Ringhals-1 stability tests and compared with the frequency domain analysis using the code STAB. A comprehensive assessment of modeling choices for the TRACE stability analysis has been made, including effects of time-space discretization and numerical schemes, thermal-hydraulics channel grouping, neutronics modeling, and control system modeling. It was found that with careful control of numerical diffusion, the predictions from TRACE agree reasonably well with the Ringhals-1 test results and the predictions from STAB. The benchmark results of both codes against the Ringhals stability test are found to be at the same level of accuracy. The biases for the predicted global decay ratio are [approximately]0.07 in TRACE results and -0.04 in STAB results. However, the standard deviations of their decay ratios are both large, [approximately]0.1, indicating large uncertainties in both analyses. The uncertainties in both modeling approaches are identified. Although the TRACE code uses more sophisticated neutronics and thermal-hydraulics models, the modeling uncertainty is not less than that of the STAB code.
