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The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Candidates for leadership provide statements: ANS Board of Directors
With the annual ANS election right around the corner, American Nuclear Society members will be going to the polls to vote for a vice president/president-elect, treasurer, and members-at-large for the Board of Directors. In January, Nuclear News published statements from candidates for vice president/president-elect and treasurer. This month, we are featuring statements from each nominee for the Board of Directors.
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.
