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Conference Spotlight
2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Modernizing I&C for operations and maintenance, one phase at a time
The two reactors at Dominion Energy’s Surry plant are among the oldest in the U.S. nuclear fleet. Yet when the plant celebrated its 50th anniversary in 2023, staff could raise a toast to the future. Surry was one of the first plants to file a subsequent license renewal (SLR) application, and in May 2021, it became official: the plant was licensed to operate for a full 80 years, extending its reactors’ lifespans into 2052 and 2053.
L.-Y. Cheng, J. S. Baek, A. Cuadra, A. Aronson, D. Diamond, P. Yarsky
Nuclear Technology | Volume 196 | Number 2 | November 2016 | Pages 238-247
Technical Paper | doi.org/10.13182/NT16-29
Articles are hosted by Taylor and Francis Online.
A TRACE/PARCS model has been developed to analyze anticipated transient without scram (ATWS) events for a boiling water reactor (BWR) operating in the maximum extended load line limit analysis-plus (MELLLA+) expanded operating domain. The MELLLA+ domain expands the allowable operation in the power/flow map of a BWR to low flow rates at high-power conditions. Such operation exacerbates the likelihood of large-amplitude power/flow oscillations during certain ATWS scenarios. The analysis shows that large-amplitude power/flow oscillations, both core-wide and out-of-phase, arise following the establishment of natural-circulation flow in the reactor pressure vessel after the trip of the recirculation pumps and an increase in core inlet subcooling. The analysis also indicates a mechanism by which the fuel may experience heatup that could result in localized fuel damage. TRACE predicts that heatup will occur when the cladding surface temperature exceeds the minimum stable film boiling temperature after periodic cycles of dryout and rewet, and the fuel becomes locked into a boiling-film regime. Further, the analysis demonstrates the effectiveness of the simulated manual operator actions to suppress the instability.