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Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.
Benjamin R. Hanna, Daniel F. Gill, David P. Griesheimer
Nuclear Technology | Volume 183 | Number 3 | September 2013 | Pages 367-378
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-A19425
Articles are hosted by Taylor and Francis Online.
An integrated thermal-hydraulic feedback module has previously been developed for the Monte Carlo transport solver MC21. The module incorporates a flexible input format that allows the user to describe heat transfer and coolant flow paths within the geometric model at any level of spatial detail desired. The effect that the varying levels of spatial homogenization of thermal regions has on the accuracy of the Monte Carlo simulations is examined in this study. Six thermal feedback mappings are constructed from the same geometric model of the Calvert Cliffs core. The spatial homogenization of the thermal regions is varied, giving each scheme a different level of detail, and the adequacy of the spatial homogenization is determined based on the eigenvalue produced by each Monte Carlo calculation. The purpose of these numerical experiments is to determine the level of detail necessary to accurately capture the thermal feedback effect on reactivity. Several different core models are considered: axial flow only, axial and lateral flow, asymmetry due to control rod insertion, and fuel heating (temperature-dependent cross sections). The thermal results generated by the MC21 thermal feedback module are consistent with expectations. Based on the numerical experiments conducted, it is concluded that the amount of spatial detail necessary to accurately capture the feedback effect on reactivity is relatively small. Homogenization at the assembly level for the Calvert Cliffs pressurized water reactor model results in a power defect similar to that calculated with individual pin cells modeled as explicit thermal regions.