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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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NRC approves V.C. Summer’s second license renewal
Dominion Energy’s V.C. Summer nuclear power plant, in Jenkinsville, S.C., has been authorized to operate for 80 years, until August 2062, following the renewal of its operating license by the Nuclear Regulatory Commission for a second time.
H. B. Rosenthal, E. A. Szymkowiak, C. H. George
Nuclear Technology | Volume 6 | Number 3 | March 1969 | Pages 191-198
Technical Paper and Note | doi.org/10.13182/NT69-A28305
Articles are hosted by Taylor and Francis Online.
An experiment was performed to study the dynamic control of a reactor by hydrogen transport and to demonstrate its load-following capabilities. The system is based on the mass transport of hydrogen between two ZrHX beds—one UO2 fueled, the other unfueled. The in-core hydrogen concentration controls the reactivity, and the resulting changes in reactor flux control the heat input into the in-core UO2-fueled bed. In turn, the in-core hydrogen concentration is controlled by changes in temperature differences between the in-core and out-of-core beds. Within analytical design constraints set by experimental and safety requirements, calculated ranges of parameters established design specifications. Preliminary validation measurements included reactor stability and temperature coefficient, experimental system stability and temperature coefficient, and in-core hydrogen worth. Comparison showed that hydrogen mass transport contributed 73% of the effectiveness of hydrogen reactivity control while temperature contributed only 27%. All experimental transient responses to step changes in thermal load exhibited analytically predicted damped oscillatory behavior. Reactor startup, shutdown, and response to reactivity changes were demonstrated. This experiment verified that hydrogen reactivity control, a mechanically passive device, is an effective, self-regulating mechanism for controlling a nuclear reactor.
