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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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OECD NEA meeting focuses on irradiation experiments
Members of the OECD Nuclear Energy Agency’s Second Framework for Irradiation Experiments (FIDES-II) joint undertaking gathered from September 29 to October 3 in Ketchum, Idaho, for the technical advisory group and governing board meetings hosted by Idaho National Laboratory. The FIDES-II Framework aims to ensure and foster competences in experimental nuclear fuel and structural materials in-reactor experiments through a diverse set of Joint Experimental Programs (JEEPs).
S. C. Wilson, S. R. Biegalski, R. L. Coats
Nuclear Science and Engineering | Volume 157 | Number 3 | November 2007 | Pages 344-353
Technical Paper | doi.org/10.13182/NSE06-28
Articles are hosted by Taylor and Francis Online.
The primary shutdown mechanism of all-metal nuclear assemblies engaging in pulsed operations is thermal expansion of the fuel material. Typically, a fuel temperature coefficient of reactivity is acquired by building the apparatus and fitting the operational data to the Nordheim-Fuchs kinetics equations. This value may vary as a function of reactivity insertion because of thermomechanical effects in the fuel material, which leads to uncertainty regarding untested reactor designs. This paper presents a computational method for modeling power, temperature, and thermoelastic displacement behavior of a spherical Godiva-like assembly during a prompt supercritical excursion and provides a way of determining fuel temperature coefficients of reactivity without the use of operational data.