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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.
M. Andersson, D. Blanchet, H. Nylén, R. Jacqmin
Nuclear Science and Engineering | Volume 185 | Number 2 | February 2017 | Pages 263-276
Technical Paper | doi.org/10.1080/00295639.2016.1272358
Articles are hosted by Taylor and Francis Online.
In axially heterogeneous fast reactor concepts, such as the Advanced Sodium Technological Reactor for Industrial Demonstration (ASTRID) CFV (French acronym of Coeur à Faible effet de Vide sodium, meaning low sodium void effect core) core, the accurate neutronic prediction of control rods is a challenge. In such cores, the performance of the classical two-dimensional (2-D) equivalence procedure, used for control rod homogenization in homogeneous fast reactors, is questionable.
In this work (part I of two companion papers), a number of axially heterogeneous environments, representative of a CFV-type core, are investigated using 2-D (X-Z) models, with the objective to distinguish regions where the classical equivalence procedure is valid from those where it is not.
It is found that the environments that affect the control rod absorber the most, and are likely to invalidate the procedure, are the internal control rod interfaces, such as the absorber/follower interface and the interface between zones of different boron enrichments. The range of the main spectral impact could be seen within 0 to 10 cm from the material interfaces studied.
In the companion paper (part II), a full-core investigation is performed that builds upon the results of this paper.