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Title: Axial grading of inert matrix fuels

Abstract

Burning actinides in an inert matrix fuel to 750 MWd/kg IHM results in a significant reduction in transuranic isotopes. However, achieving this level of burnup in a standard light water reactor would require residence times that are twice that of uranium dioxide fuels. The reactivity of an inert matrix assembly at the end of life is less than 1/3 of its beginning of life reactivity leading to undesirable radial and axial power peaking in the reactor core. Here we show that axial grading of the inert matrix fuel rods can reduce peaking significantly. Monte Carlo simulations are used to model the assembly level power distributions in both ungraded and graded fuel rods. The results show that an axial grading of uranium dioxide and inert matrix fuels with erbium can reduces power peaking by more than 50% in the axial direction. The reduction in power peaking enables the core to operate at significantly higher power. (authors)

Authors:
;  [1]
  1. Dept. of Mechanical Engineering, Univ. of Texas, Austin, TX (United States)
Publication Date:
Research Org.:
American Nuclear Society, Inc., 555 N. Kensington Avenue, La Grange Park, Illinois 60526 (United States)
OSTI Identifier:
22105701
Resource Type:
Conference
Resource Relation:
Conference: PHYSOR 2012: Conference on Advances in Reactor Physics - Linking Research, Industry, and Education, Knoxville, TN (United States), 15-20 Apr 2012; Other Information: Country of input: France; 5 refs.
Country of Publication:
United States
Language:
English
Subject:
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; ACTINIDES; BURNUP; COMPUTERIZED SIMULATION; ERBIUM; ERBIUM ISOTOPES; FUEL RODS; MONTE CARLO METHOD; POWER DISTRIBUTION; REACTIVITY; REACTOR CORES; TRANSMUTATION; URANIUM DIOXIDE; WATER COOLED REACTORS; WATER MODERATED REACTORS

Citation Formats

Recktenwald, G. D., and Deinert, M. R. Axial grading of inert matrix fuels. United States: N. p., 2012. Web.
Recktenwald, G. D., & Deinert, M. R. Axial grading of inert matrix fuels. United States.
Recktenwald, G. D., and Deinert, M. R. 2012. "Axial grading of inert matrix fuels". United States. doi:.
@article{osti_22105701,
title = {Axial grading of inert matrix fuels},
author = {Recktenwald, G. D. and Deinert, M. R.},
abstractNote = {Burning actinides in an inert matrix fuel to 750 MWd/kg IHM results in a significant reduction in transuranic isotopes. However, achieving this level of burnup in a standard light water reactor would require residence times that are twice that of uranium dioxide fuels. The reactivity of an inert matrix assembly at the end of life is less than 1/3 of its beginning of life reactivity leading to undesirable radial and axial power peaking in the reactor core. Here we show that axial grading of the inert matrix fuel rods can reduce peaking significantly. Monte Carlo simulations are used to model the assembly level power distributions in both ungraded and graded fuel rods. The results show that an axial grading of uranium dioxide and inert matrix fuels with erbium can reduces power peaking by more than 50% in the axial direction. The reduction in power peaking enables the core to operate at significantly higher power. (authors)},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2012,
month = 7
}

Conference:
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  • Problems arising from the accumulation of plutonium stock, whether from civil origin or resulting from arms reform, are beginning to be well defined, and a major international effort has been undertaken. Obviously, elements of solutions to problems linked to multirecycling and plutonium in-reactor optimization may be found in the short and medium runs by taking into account the capacities of composite fuels in an inert matrix in the fields of neutronics and material sciences. A composite fuel without uranium in an inert matrix increases the consumption of plutonium, as the conversion source ({sup 238}U) is eliminated at design. The presentedmore » plutonium multirecycling scenario shows that balancing the incoming-outgoing plutonium fluxes for the French pool is possible, and if approximately a third of the pool uses this type of fuel, fluxes may very rapidly be balanced.« less
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