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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.
Albert G. Gu
Nuclear Technology | Volume 177 | Number 2 | February 2012 | Pages 157-175
Technical Paper | Fission Reactors | doi.org/10.13182/NT12-A13363
Articles are hosted by Taylor and Francis Online.
This paper introduces a combined micro and macro (CMM) parameter perturbation theory for boiling water reactor (BWR) lattice design and optimization, which involves a large number of independent design variables and a large scale of variations. With this theory, engineers are able to meet the challenges from both accuracy and speed requirements. This theory was applied to the BWR fuel assembly lattice design in AREVA. A BWR fast lattice simulator (FLS) and a BWR fuel assembly lattice optimizer (BALO) were built and assisted engineers working on the lattice design and optimization. In addition to the discussion of this theory, the BALO/FLS calculation results are used to show that this theory can meet both speed and accuracy criteria of design as well as cover the large design range. Moreover, the results also show that two major perturbation issues in BWR lattice design and optimization, i.e., the large swing of average lattice enrichment and the thermal neutron black absorber's distribution as burnable poison can be resolved with the CMM perturbation theory. Finally, it is pointed out that the macro parameter perturbation combined with the micro parameter perturbation is extremely important to the accuracy.