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Division Spotlight
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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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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.
T. Höhne, E. Krepper, D. Lucas, G. Montoya
Nuclear Technology | Volume 205 | Number 1 | January-February 2019 | Pages 48-56
Technical Paper | doi.org/10.1080/00295450.2018.1495025
Articles are hosted by Taylor and Francis Online.
The paper presents the extension of the GENeralized TwO Phase flow (GENTOP) model for phase transfer and discusses the submodels used. Boiling flow inside a wall heated vertical pipe is simulated by a multifield computational fluid dynamics (CFD) approach. Subcooled water enters the pipe from the lower end and heats up first in the near-wall region leading to the generation of small bubbles. Farther along the pipe, larger and larger bubbles are generated by coalescence and evaporation. This leads to transitions of the two-phase-flow patterns from bubbly to churn-turbulent and annular flow. The CFD simulation is based on the recently developed GENTOP concept. It is a multifield model using the Euler-Euler approach. It allows the consideration of different local flow morphologies including transitions between them. Small steam bubbles are handled as dispersed phases while the interface of large gas structures is statistically resolved. The GENTOP submodels and the wall boiling model need a constant improvement and separate, intensive validation effort using CFD-grade experiments.