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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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DOE issues new NEPA rule and procedures—and accelerates DOME reactor testing
Meeting a deadline set in President Trump’s May 23 executive order “Reforming Nuclear Reactor Testing at the Department of Energy,” the DOE on June 30 updated information on its National Environmental Policy Act (NEPA) rulemaking and implementation procedures and published on its website an interim final rule that rescinds existing regulations alongside new implementing procedures.
Constantine P. Tzanos, B. Dionne
Nuclear Technology | Volume 179 | Number 3 | September 2012 | Pages 382-391
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT12-A14170
Articles are hosted by Taylor and Francis Online.
To support the safety analysis of the conversion of the BR2 research reactor to low-enriched uranium (LEU) fuel and extend the validation basis of the RELAP code for the analysis of the conversion of research reactors from highly enriched (HEU) fuel to LEU, the simulation of BR2 tests A/400/1, C/600/3, and F/400/1 was undertaken. These tests are characterized by loss of flow initiated at different reactor power levels with or without loss of system pressure, reactor scram, flow reversal, and reactor cooling by natural circulation. This work presents the RELAP analysis of tests C/600/3 and F/400/1 and comparison of code predictions with experimental measurements for peak cladding temperatures during the transient at different axial locations in an instrumented fuel assembly. The simulations show that accurate representation of the power distribution, especially after reactor scram, between the fuel assemblies and the moderator/reflector regions is critical for the correct prediction of the peak cladding temperatures during the transient. Detailed MCNP and ORIGEN simulations were performed to compute the power distribution between the fuel assemblies and the moderator/reflector regions. With these distributions the predicted peak cladding temperatures are in good agreement with experimental measurements.