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MARVEL team shares lessons learned through microreactor development
On June 1 at the American Nuclear Society’s Annual Conference in Denver, Colo., a team from Idaho National Laboratory presented a session titled “Lessons Learned from MARVEL Reactor Fabrication.” The presentation highlighted challenges that arose as they moved from design to manufacturing and assembly, with a focus on reactor part fabrication, Stirling engine implementation, and reactivity control system development.
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.