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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
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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Latest News
DOE extends Centrus’s HALEU production contract by one year
Centrus Energy has announced that it has secured a contract extension from the Department of Energy to continue—for one year—its ongoing high-assay low-enriched uranium (HALEU) production at the American Centrifuge Plant in Piketon, Ohio, at an annual rate of 900 kilograms of HALEU UF6. According to Centrus, the extension is valued at about $110 million through June 30, 2026.
T. F. Wimett, H. C. Paxton
Nuclear Science and Engineering | Volume 78 | Number 4 | August 1981 | Pages 425-431
Technical Note | doi.org/10.13182/NSE81-A21379
Articles are hosted by Taylor and Francis Online.
A critical assembly with circulating enriched uranium solution was operated for brief periods at power up to 2 MW corresponding to a core temperature differential of 13°C. Although delayed neutron precursors were swept out of the critical region, contributing little to control, power followed excess reactivity satisfactorily. At excess reactivity of 0.2 dollar, power oscillations began to appear, and above ∼0.5 dollar they diverged. The 1-s period appears to be associated with vibration of unconstrained piping. Reactivity quench coefficients are greater than those measured without flow. The difference is attributed to macroscopic release of radiolytic gas.