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Division Spotlight
Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
Penn State and Westinghouse make eVinci microreactor plan official
Penn State and Westinghouse Electric Company are working together to site a new research reactor on Penn State’s University Park, Pa., campus: Westinghouse’s eVinci, a HALEU TRISO-fueled sodium heat-pipe reactor. Penn State has announced that it submitted a letter of intent to host and operate an eVinci reactor to the Nuclear Regulatory Commission on February 28 and plans to engage with the NRC on specific siting decisions. Penn State already boasts the Breazeale reactor, which began operating in 1955 as the first licensed research reactor at a university in the United States. At 70, the Breazeale reactor is still in operation.
H. A. Sandmeier
Nuclear Science and Engineering | Volume 6 | Number 2 | August 1959 | Pages 85-92
Technical Paper | doi.org/10.13182/NSE59-A25637
Articles are hosted by Taylor and Francis Online.
For large perturbations the usual assumption in power reactor stability that the flux variations δn are small in comparison with the steady-state flux level n0 is not valid. Due to the product term of excess reactivity and neutron flux, harmonies are generated in the flux. The stability under such conditions can be discussed by extracting the fundamental flux component and obtaining a quasi frequency response as the ratio of fundamental incremental flux component to excess reactivity as a function of frequency and amplitude of perturbation. This approach is applied to two Argonne power reactors, the Experimental Boiling Water Reactor (EBWR) and the Experimental Breeder Reactor (EBR-I), where experimental frequency responses have been obtained and a peak has been observed. It is found that for both reactors the stability decreases as the amplitude of perturbation increases.
