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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).”
Jaeha Kim, Yonghee Kim
Nuclear Science and Engineering | Volume 194 | Number 1 | January 2020 | Pages 1-13
Technical Paper | doi.org/10.1080/00295639.2019.1642016
Articles are hosted by Taylor and Francis Online.
This paper presents the methodology and performance of the Hybrid Coarse-Mesh Finite Difference (HCMFD) algorithm for transient pinwise analyses of three-dimensional (3-D) pressurized water reactor (PWR) problems. The time-dependent neutron diffusion equations and their applications in two steps of the HCMFD algorithm, i.e., local and global iterations, are introduced in detail. Taking into account the characteristics of the local-global nonlinear HCMFD iterations, an optimization strategy to minimize the computing time of the transient HCMFD calculation is established by focusing on the balance between the number of local and global calculations. Based on the optimization strategy, the actual computational performance of the transient HCMFD algorithm, in view of both computing time and accuracy, is evaluated for the core of a big-sized conventional PWR in this work. To demonstrate the effectiveness of the optimized iteration strategy, various slow and fast transients including a rod ejection transient are simulated by the transient HCMFD algorithm. It is clearly shown that a 3-D pin-resolved whole-core transient solution for a big PWR can be obtained in a reasonably short computing time by the transient 3-D HCMFD algorithm.