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Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
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Chicago, IL|Chicago Marriott Downtown
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Latest News
NRC v. Texas: Supreme Court weighs challenge to NRC authority in spent fuel storage case
The State of Texas has not one but two ongoing federal court challenges to the Nuclear Regulatory Commission that could, if successful, turn decades of NRC regulations, precedent, and case law on its head.
Hiroshi Motoda, John Herczeg, Alexander Sesonske
Nuclear Technology | Volume 25 | Number 3 | March 1975 | Pages 477-496
Technical Paper | Fuel Cycle | doi.org/10.13182/NT75-A24386
Articles are hosted by Taylor and Francis Online.
A stagewise optimization of the refueling schedule for light-water reactors has been developed with emphasis on the nuclear model. The decision variables to be determined are end-of-cycle (EOC) reactivity distribution, energy output, power distribution, number of fresh fuel assemblies, number of reinsertion of used assemblies, selection of assemblies for discharge, and allocation of each fuel assembly in a two-dimensional core geometry. Division of the total problem into six phases permits usage of the most effective method in each phase. This study employed such techniques as linear programming for regionwise shuffling optimization, linear iterative search for the optimal EOC state, the minimum integrated k-deviation method for a guess allocation, and direct search for the optimal allocation of each fuel assembly, etc., all of which are interrelated. The applicability of this method to a commercial light-water reactor was demonstrated for a 1300-MW(th) boiling-water reactor by successfully generating a ten-cycle refueling schedule using a fixed enrichment of initial and reload fuel and allowing reinsertion of discharged fuel assemblies from the first to the third cycles. The results indicate a savings of as much as 14% of the fresh fuel consumption over a conventional mixed four- and five-batch scatter loading, with thermal characteristics well within design limits.