Conservative Axial Burnup Distributions for Actinide-Only Burnup Credit

Conference · Mon May 11 04:00:00 EDT 1998

OSTI ID:645517

Kang, Chi ^[1]; Lancaster, Dale ^[1]

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1. TRW Environmental Safety Systems, Inc., Vienna, VA (United States)

Unlike the fresh fuel approach, which assumes the initial isotopic compositions for criticality analyses, any burnup credit methodology must address the proper treatment of axial burnup distributions. A straightforward way of treating a given axial burnup distribution is to segment the fuel assembly into multiple meshes and to model each burnup mesh with the corresponding isotopic compositions. Although this approach represents a significant increase in modeling efforts compared to the uniform average burnup approach, it can adequately determine the reactivity effect of the axial burnup distribution. A major consideration is what axial burnup distributions are appropriate for use in light of many possible distributions depending on core operating conditions and histories. This paper summarizes criticality analyses performed to determine conservative axial burnup distributions. The conservative axial burnup distributions presented in this paper are included in the Topical Report on Actinide-Only Burnup Credit for Pressurized Water Reactor Spent Nuclear Fuel Packages, Revision 1 submitted in May 1997 by the US Department of Energy (DOE) to the US Nuclear Regulatory Commission (NRC). When approved by NRC, the conservative axial burnup distributions may be used to model PWR spent nuclear fuel for the purpose of gaining actinide only burnup credit.

• Research Organization: TRW Environmental Safety Systems, Inc., Vienna, VA (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Nuclear Criticality Safety Program (NCSP)
• DOE Contract Number: AC08-91RW00134
• OSTI ID: 645517
• Report Number(s): DOE/RW/00134--M97-019; CONF-980516--; ON: DE98001300; BR: DB0306000
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
ACTINIDES
BURNUP
Burnup Credit Methodology
CRITICALITY
Fresh Fuel Approach
ISOTOPE RATIO
Nuclear Criticality Safety Program (NCSP)
PWR TYPE REACTORS
Pressurized Water Reactor (PWR)
SPENT FUELS
Spent Nuclear Fuel