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Conference 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
A new ANSI/ANS standard for liquid metal fire protection published
ANSI/ANS-54.8-2025, Liquid Metal Fire Protection in LMR Plants, received approval from the American National Standards Institute on September 2 and is now available for purchase.
The 2025 edition is a reinvigoration of the withdrawn ANS-54.8-1988 of the same title. The Advanced Reactor Codes and Standards Collaborative (ARCSC) identified the need for a current version of the standard via an industry survey.
Typical liquid metal reactor designs use liquid sodium as the coolant for both the primary and intermediate heat-transport systems. In addition, liquid sodium and NaK (a mixture of sodium and potassium that is liquid at room temperature) are often used in auxiliary heat-removal systems. Since these liquid metals can react readily with oxygen, water, and other compounds, special precautions must be taken in the design, construction, testing, and maintenance of the sodium/NaK systems to ensure that the potential for leakage is very small.
Geza L. Gyorey
Nuclear Science and Engineering | Volume 13 | Number 4 | August 1962 | Pages 338-344
Technical Paper | doi.org/10.13182/NSE62-A26175
Articles are hosted by Taylor and Francis Online.
This paper deals with the space and time dependent reactor stability problem of neutron flux shape variations due to xenon-135. The effect of modal interaction on stability is investigated for a simple reactor model when the characteristic functions of the wave equation are used in a modal expansion. It is shown that modal interaction may contribute to or detract from stability depending on the circumstances, and that in the case of a very large reactor, stability can be seriously overestimated if modal interaction is neglected.
