Fission gas swelling in U{sub 3}Si{sub 2} at LWR conditions

Conference · Fri Jul 01 04:00:00 EDT 2016

OSTI ID:22765229

Miao, Y.; Ye, B.; Mei, Z. G.; Mo, K.; Hofman, G.; Yacout, A. M. ^[1]; Andersson, D. ^[2]

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1. Nuclear Engineering Division, Argonne National Laboratory, Lemont, IL 61801 (United States)
2. Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

In order to evaluate the feasibility of replacing uranium dioxide fuel with U{sub 3}Si{sub 2} fuel, it is crucial to examine the fuel performance of the silicide fuel under typical LWR conditions. At this early stage of U{sub 3}Si{sub 2} fuel development, before undertaking costly in-pile irradiation experiments and corresponding post-irradiation examinations, it is appropriate to utilize modeling tools to estimate the behavior of U{sub 3}Si{sub 2} in LWRs based on available in-pile irradiation experiments as well as the state-of-the-art calculation capabilities provided by density functional theory (DFT). Therefore, a comprehensive investigation of the fission gas swelling behavior of U{sub 3}Si{sub 2} at LWR conditions is reported here. The modeling efforts in this study are based on the Gas Release and Swelling Subroutine for Steady-State and Transient (GRASS-SST) rate theory (RT) model of fission gas bubble evolution that has been successfully applied to a variety of fuel materials in numerous types of reactors. Both existing in-pile irradiation data and DFT-based calculations were used for the optimized parametrization of the RT model. In addition, the fuel-cladding interaction was captured by coupling the RT model with simplified mechanical correlations. Both the swelling behavior and the fission gas bubble size distribution were predicted by the rate theory model. At LWR conditions, the RT model predicts that intragranular bubbles dominate the gaseous swelling behavior and that the evolution of intergranular bubbles and corresponding gas release are suppressed, confirming the qualification of U{sub 3}Si{sub 2} as a LWR fuel.

• Research Organization: American Nuclear Society - ANS, 555 North Kensington Avenue, La Grange Park, IL 60526 (United States)
• OSTI ID: 22765229
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
42 ENGINEERING
BUBBLES
COMPUTERIZED SIMULATION
DENSITY FUNCTIONAL METHOD
FISSION PRODUCT RELEASE
FISSION PRODUCTS
FUEL-CLADDING INTERACTIONS
GAS FLOW
IRRADIATION
NUCLEAR FUELS
POST-IRRADIATION EXAMINATION
STEADY-STATE CONDITIONS
SWELLING
URANIUM DIOXIDE
URANIUM SILICIDES
WATER COOLED REACTORS