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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.
Wang-Kee In, Tae-Hyun Chun, Chang-Hwan Shin, Dong-Seok Oh
Nuclear Technology | Volume 161 | Number 1 | January 2008 | Pages 69-79
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT08-A3914
Articles are hosted by Taylor and Francis Online.
A series of computational fluid dynamics (CFD) simulations has been conducted to analyze the heat transfer enhancement in a fully heated rod bundle with mixing-vane spacers. The predicted Nusselt numbers downstream of the split-vane spacer are compared with the available experimental measurements and with correlation. The CFD calculations at Re = 28000 and 42000 showed a lower heat transfer enhancement close to the space grid but a good agreement of the decay rate with the fully heated experimental data at ~6Dh downstream of the grid. The CFD simulations also showed a maximum enhancement of the heat transfer at 6 to 7Dh downstream of the split-vane spacer due to the multiple vortices predicted near the spacer. In addition, the present paper compares the thermal-hydraulic performance of two different mixing vane spacers, i.e., a split-vane spacer and a hybrid-vane spacer, based on CFD simulations at a pressurized water reactor's operating conditions. The split vane is predicted to have a higher overall heat transfer enhancement but a lower local heat transfer far downstream of the spacer where the minimum departure from nucleate boiling ratio is anticipated.