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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.
Sang Ji Kim, Pham Nhu Viet Ha, Jae Yong Lim, Won Sik Yang
Nuclear Technology | Volume 186 | Number 3 | June 2014 | Pages 390-402
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT13-90
Articles are hosted by Taylor and Francis Online.
A core design study to convert a breakeven core into a transuranic (TRU) burner is performed for a 600-MW(electric)–rated metal-fueled sodium-cooled fast reactor. No change in the core and subassembly layouts is assumed, which only allows geometry variations within the fuel rods. Investigated alternatives are to use variable cladding thicknesses (VCTs), smearing fraction (SF) adjustments, and annular fuel rod concepts with a central liner of a variable diameter consisting of void, Zr, B4C, Al, etc. The VCT concept could not be employed due to a too-high clad inner wall temperature. A SF adjustment below a typical fraction of 75% leads to moderate TRU burning and a reduced sodium void worth but also to a relatively high burnup swing. Placing a central nonfuel rod with the fuel arranged in an annular ring affects the core performance and reactivity coefficients, depending on whether it is a moderator or an absorber. In general, candidate materials of high atomic numbers contribute to large positive sodium void worths but also enhanced negative expansion effects. Among the light elements, vanadium reveals a favorable performance with comparable TRU burning and a reduced sodium void worth, suggesting this material can be regarded as a substitute for sodium in the solid state.