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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).”
Yasuhide Senda, Seiji Shiroya, Masatoshi Hayashi, Keiji Kanda
Nuclear Technology | Volume 70 | Number 3 | September 1985 | Pages 318-334
Technical Paper | Fission Reactor | doi.org/10.13182/NT85-A15959
Articles are hosted by Taylor and Francis Online.
The results of analyses on the void reactivity measurements performed in the Kyoto University Critical Assembly using medium-enriched uranium fuel as well as highly enriched uranium fuel are provided. In consideration of the heterogeneity of a complex core, four-group constants were generated by SRAC, a standard thermal reactor code system for reactor design and analysis at the Japan Atomic Energy Research Institute. The eigenvalue and perturbation calculations were subsequently performed by the 2D-FEM-KUR code, which is a two-dimensional diffusion code based on the finite element method. The calculated eigenvalue keff agreed with the measured value to within 0.5% in the calculated-to-experiment ratio. The void reactivity calculated by perturbation theory approximately reproduced the experimental data including the spatial dependence. The discrepancy between the calculated and measured void reactivity was <0.05 × 10−3 Δ k / k per voided flow channel.