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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
Jay E. Boudreau, R. C. Erdmann
Nuclear Science and Engineering | Volume 51 | Number 2 | June 1973 | Pages 206-222
Technical Paper | doi.org/10.13182/NSE73-A26595
Articles are hosted by Taylor and Francis Online.
Secondary criticality resulting from massive core rearrangement is discussed where the material dynamics results from either mild or strong initial excursions. Diffusion theory is used to study the effect of moving boundaries on the flux, and to study the effect of internal fuel rearrangement on keff. Numerical transport methods are used to make accurate determinations of keff for complicated fuel configurations arising from disassembly calculations. It is concluded that secondary criticality may occur from fuel rearrangement, but that it is unlikely in most cases. Variations in core height/diameter ratio, zonal enrichment, and overall size can change the tendency for autocatalysis significantly.