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Atlanta, GA|Atlanta Marriott Marquis
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Spent fuel transfer project completed at INL
Work crews at Idaho National Laboratory have transferred 40 spent nuclear fuel canisters into long-term storage vaults, the Department of Energy’s Office of Environmental Management has reported.
Yousef M. Farawila
Nuclear Science and Engineering | Volume 129 | Number 3 | July 1998 | Pages 261-272
Technical Paper | doi.org/10.13182/NSE98-A1980
Articles are hosted by Taylor and Francis Online.
A modal neutron kinetics method was developed and applied to new problems with boiling water reactor oscillations. The modal method is uniquely suited for such problems because the oscillation components, in-phase and out-of-phase, correspond directly to separate expansion functions. One problem is understanding the origin and predicting the magnitude of the in-phase component that is always present during out-of-phase power oscillations. Another exercise of the method was the calculation of the relative critical power ratio (CPR) response to in-phase and out-of-phase oscillations, known as the DIVOM curve, using a fast single hydraulic channel model. The new calculations confirm the BWR owners group results and similar calculations using the full three-dimensional neutronics and multichannel models of the RAMONA-3 code. In addition, the origin of the large difference between the in-phase and out-of-phase CPR responses could be explained. Modal analysis of the reactivity biases associated with oscillating reactivity insertions for the two known modes could explain the out-of-phase mode higher propensity to growth compared with the in-phase mode of oscillation.