The Width of High Burnup Structure in LWR UO{sub 2} Fuel

Conference · Sun Jul 01 04:00:00 EDT 2007

OSTI ID:21229295

Koo, Yang-Hyun; Lee, Byung-Ho; Oh, Jae-Yong; Sohn, Dong-Seong ^[1]

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1. Korea Atomic Energy Research Institute, Innovative Water Reactor Fuel Center, P.O.Box 105, Yuseong, Daejeon 305-600 (Korea, Republic of)

The measured data available in the open literature on the width of high burnup structure (HBS) in LWR UO{sub 2} fuel were analyzed in terms of pellet average burnup, enrichment, and grain size. Dependence of the HBS width on pellet average burnup was shown to be divided into three regions; while the HBS width is governed by accumulation of fission damage (i.e., burnup) for burnup below 60 GWd/tU, it seems to be restricted to some limiting value of around 1.5 mm for burnup above 75 GWd/tU due to high temperature which might have caused extensive annealing of irradiation damage. As for intermediate burnup between 60 and 75 GWd/tU, although temperature would not have been so high as to induce extensive annealing, the microstructural damage could have been partly annealed, resulting in the reduction of the HBS width. It was found that both enrichment and grain size also affects the HBS width. However, as long as the pellet average burnup is lower than about 75 GWd/tU, the effect does not appear to be significant for the enrichment and grain size that are typically used in current LWR fuel. (authors)

• Research Organization: American Nuclear Society, 555 North Kensington Avenue, La Grange Park, IL 60526 (United States)
• OSTI ID: 21229295
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
36 MATERIALS SCIENCE
ANNEALING
BURNUP
FUEL PELLETS
GRAIN SIZE
LIMITING VALUES
NUCLEAR FUELS
TEMPERATURE RANGE 0400-1000 K
URANIUM DIOXIDE