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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.
Cihang Lu, Zeyun Wu
Nuclear Technology | Volume 208 | Number 10 | October 2022 | Pages 1577-1590
Technical Paper | doi.org/10.1080/00295450.2022.2049966
Articles are hosted by Taylor and Francis Online.
Equilibrium state generation for the pebble bed reactor (PBR) is challenging due to the need to simultaneously account for both pebble movement and changes in fuel compositions. Multigroup diffusion codes have been historically employed to generate the equilibrium state and perform conventional neutronics calculations for PBRs, while neutron cross-section generation has been challenging due to the double heterogeneity of PBRs. Thanks to the capability to treat the double heterogeneity naturally, continuous-energy Monte Carlo (MC) methods are more suitable for detailed PBR analysis, but at the cost of significantly higher computing power.
This paper presents a new Methodology to Efficiently Estimate the Equilibrium State of a PBR (MEEES-PBR) to generate equilibrium-state MC models for PBRs at lower computational expense. The MEEES-PBR is expected to contribute to the future development of PBR designs by accelerating the efforts in core designs and parametric studies. The theory of the MEEES-PBR is introduced in detail in this paper, and the procedure is demonstrated via an example application to the 165-MW(thermal) Xe-100 design. The computational cost and the accuracy of the MEEES-PBR are discussed to prove its viability.