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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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DOE on track to deliver high-burnup SNF to Idaho by 2027
The Department of Energy said it anticipated delivering a research cask of high-burnup spent nuclear fuel from Dominion Energy’s North Anna nuclear power plant in Virginia to Idaho National Laboratory by fall 2027. The planned shipment is part of the High Burnup Dry Storage Research Project being conducted by the DOE with the Electric Power Research Institute.
As preparations continue, the DOE said it is working closely with federal agencies as well as tribal and state governments along potential transportation routes to ensure safety, transparency, and readiness every step of the way.
Watch the DOE’s latest video outlining the project here.
D. J. Euh, B. G. Huh, B. J. Yun, C.-H. Song, I. G. Kim
Nuclear Technology | Volume 164 | Number 3 | December 2008 | Pages 368-384
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT164-368
Articles are hosted by Taylor and Francis Online.
The reflood rate in a core is an important parameter for core cooling during a large-break loss-of-coolant-accident (LBLOCA) reflood period, and it strongly depends on the thermal-hydraulic conditions in the downcomer. During this period, downcomer boiling has an important influence on the transient behavior of a postulated LBLOCA because it can degrade the hydraulic head in a downcomer and consequently affect the reflood flow rate for core cooling. Although it is recognized that downcomer boiling is critical to correctly predict the reflood phenomena of an LBLOCA transient, especially for a direct vessel injection adapted system like the advanced power reactor APR1400, the amount of experimental data and code assessment in this area is relatively limited. To improve the state of knowledge relative to downcomer boiling, a test program at the Downcomer Boiling (DOBO) facility is progressing for the reflood phase of a postulated LBLOCA. The DOBO facility was designed to meet a full scale for the height and gap of a reactor downcomer. The DOBO test revealed a strong multidimensional boiling behavior, which induces the need for performance evaluation of the best-estimate codes that are used to analyze a nuclear reactor's thermal-hydraulic safety, since they have mostly been used for one-dimensional system behavior. In this study, RELAP, MARS, and TRACE are evaluated by using measured two-phase-flow data. Based on the assessments, the modeling capability and weak points of the safety analysis codes are addressed for multidimensional downcomer boiling phenomena. Two models for a downcomer are considered to assess the codes for the DOBO tests, which are also applied to a plant analysis.