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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.
Keiichi Mochizuki, Atushi Takeda
Nuclear Science and Engineering | Volume 7 | Number 4 | April 1960 | Pages 336-344
Technical Paper | doi.org/10.13182/NSE60-A25727
Articles are hosted by Taylor and Francis Online.
Neutron flux spatial oscillation due to xenon build-up in the reactor core is a well-known characteristic of large power reactors. Especially a reactor with a positive temperature coefficient of reactivity tends to have such a characteristic. In this paper, the analysis has been pursued on a Calder Hall type reactor. Specific features to be taken into consideration were a large neutron flux flattened zone in the core and a graphite sleeve in each coolant channel. First, the threshold values of the temperature coefficient for initiating oscillation of successive orders of modes in radial and azimuthal directions as well as oscillation periods have been calculated. Secondly, the effect of the sleeve on threshold value and oscillation period has been investigated. Thirdly, in order to clarify this phenomenon, a vector analysis has been made which helps us to understand the critical condition for initiating the oscillation as well as the relation between effects of neutron leakage, temperature coefficients of fuel and moderator, and xenon poisoning. Finally, taking advantage of the transfer function defined in each mode, the spatial control method could be analyzed without using a spatial simulator.
