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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.
H. van Dam
Nuclear Science and Engineering | Volume 129 | Number 3 | July 1998 | Pages 273-282
Technical Paper | doi.org/10.13182/NSE98-A1981
Articles are hosted by Taylor and Francis Online.
An analysis is presented of reactor dynamics during inherent shutdown and recriticality after loss of cooling without scram. The influence of the strength of external neutron sources is studied, and the dynamics of fission product decay heat is explicitly taken into account. It is shown that decay heat and (in thermal reactors) xenon dynamics play a dominant role in inherent reactor shutdown. Fission power level at first spontaneous recriticality is determined by both the strength of the external/inherent neutron sources and the reactivity ramp rate induced by xenon decay and cooling down of the subcritical reactor core. The first power surge after recriticality is only very weakly dependent on the external/inherent neutron source strength, and the amplitude of fission power oscillations is mainly determined by the reactivity ramp rate at first recriticality. Frequency and stability of the power oscillations after recriticality depend on the thermal inertia of the core and the power-reactivity defect. Stability is slightly deteriorated by the fission product decay dynamics, but the influence of xenon dynamics is negligible.