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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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).”
S. E. Corno, M. L. Buzano, P. Ravetto
Nuclear Science and Engineering | Volume 105 | Number 2 | June 1990 | Pages 142-159
Technical Paper | doi.org/10.13182/NSE90-A23744
Articles are hosted by Taylor and Francis Online.
An original technique for deriving the closed form solution of the multigroup system of time- and space-dependent neutron diffusion equations is reported and applied to a nonuniform multiplying structure of particular interest in cylindrical geometry. The problem of evaluating the time eigenvalues, the dynamic eigenstates, and the asymptotic power behavior of mixed fuel cores, where localized variations of the delayed neutron yield of the fuel occur, is analyzed on a rigorous basis and solved for significant sample geometries. The results provide a sound basis for establishing the region of a core where a significant amount of plutonium will induce the “minimum damage” to the overall dynamic characteristics of the reactor. These results also provide the “more suitable spatial distributions” to be assigned to a limited quantity of uranium to improve the dynamic performance of a nonuniform core, basically fueled with plutonium or mixed fissionable materials. Hence, it can be stated, on a rigorous a priori basis, the conditions where the plutonium energy release can be made as safe as possible.