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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.
John D. Burtt, Louis M. Shotkin, Joseph L. Staudenmeier
Nuclear Technology | Volume 119 | Number 3 | September 1997 | Pages 244-268
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT97-A35401
Articles are hosted by Taylor and Francis Online.
Calculations were performed for the same accident scenario in the same power plant geometry using the same version of the RELAP5/MOD3.2 computer code, but each calculation was performed using different user options in the code input deck. The accident scenario analyzed was a 1-in. cold-leg break in the new Westing-house AP600 design. The calculations were analyzed for those key events leading to actuation of the AP600 automatic depressurization system. Three different user choices for plant system noding were used: (a) a detailed noding with a quasi-three-dimensional vessel; (b) a simplified system noding with a quasi-three-dimensional core, lower plenum, and upper plenum, but a simplified downcomer noding; and (c) a detailed system and downcomer noding, but a one-dimensional core, lower plenum, and upper plenum. Two other user options were separately exercised, i.e., shutting off the model for thermal stratification and using different initial temperatures for the core. The discussion focuses on the relative effect of these different user options on flow through the P-loop hot leg, initial reversal in flow through the pressure balance line, timing of draining of the core makeup tanks, and timing of actuation of the automatic depressurization system.