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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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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The 2025 edition is a reinvigoration of the withdrawn ANS-54.8-1988 of the same title.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.
A. Z. Akcasu, A. Dalfes
Nuclear Science and Engineering | Volume 8 | Number 2 | August 1960 | Pages 89-94
Technical Paper | doi.org/10.13182/NSE60-A25783
Articles are hosted by Taylor and Francis Online.
The question of nonlinear stability of stationary reactor systems is investigated by two methods. The first method is analytic and sets the theory of nonlinear stability on a firm mathematical basis. The second method makes use of an electrical analogy and is based on the stability criterion stated by Weinberg and Ergen for nonlinear mechanical systems. Both methods deal with reactor systems in which feedback may be nonlinear as well as linear. The effect of delayed neutrons is included in the treatment. The stability conditions previously derived by others are shown to be special cases of the criteria proposed in this paper.
