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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).
Bradley J. Knutson, Richard A. Harris
Nuclear Technology | Volume 89 | Number 1 | January 1990 | Pages 9-17
Technical Paper | Fission Reactor | doi.org/10.13182/NT90-A34355
Articles are hosted by Taylor and Francis Online.
Experience using an automated core reactivity monitoring technique at the Fast Flux Test Facility (FFTF) through eight operating cycles is described. This technique relies on comparing predicted-to-measured rod positions to detect any anomalous (or unpredicted) core reactivity changes. Reactivity worth predictions of core state changes (e.g., temperature and irradiation changes) and compensating control rod movements are required for the rod position comparison. A substantial data base now exists to evaluate changes in temperature feedback reactivity effects operational in the FFTF, rod worth changes due to core loading, temperature and irradiation effects, and burnup effects associated with transmutation of fuel materials. This preliminary work focuses on resolving observed reactivity anomalies by evaluating the prediction models using additional zero-power rod worth measurement data along with calculations of rod worths and burnup rates for each cycle using cross-section data processed from the latest ENDF/B-V data set.