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Title: Gaseous swelling of U 3 Si 2 during steady-state LWR operation: A rate theory investigation

Rate theory simulations of fission gas behavior in U 3Si 2 are reported for light water reactor (LWR) steady-state operation scenarios. We developed a model of U 3Si 2 and implemented into the GRASS-SST code based on available research reactor post-irradiation examination (PIE) data, and density functional theory (DFT) calculations of key material properties. Simplified peripheral models were also introduced to capture the fuel-cladding interaction. The simulations identified three regimes of U 3Si 2 swelling behavior between 390 K and 1190 K. Under typical steady-state LWR operating conditions where U 3Si 2 temperature is expected to be below 1000 K, intragranular bubbles are dominant and fission gas is retained in those bubbles. The consequent gaseous swelling is low and associated degradation in the fuel thermal conductivity is also limited. Those predictions of U 3Si 2 performance during steady-state operations in LWRs suggest that this fuel material is an appropriate LWR candidate fuel material. Fission gas behavior models established based on this work are being coupled to the thermo-mechanical simulation of the fuel behavior using the BISON fuel performance multi-dimensional finite element code.
ORCiD logo [1] ;  [2] ;  [3] ;  [1] ;  [1] ;  [1] ;  [1]
  1. Argonne National Lab. (ANL), Lemont, IL (United States)
  2. Idaho National Lab. (INL), Idaho Falls, ID (United States)
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0029-5493; 133498
Grant/Contract Number:
AC02-06CH11357; AC07-05ID14517; AC52-06NA25396
Accepted Manuscript
Journal Name:
Nuclear Engineering and Design
Additional Journal Information:
Journal Volume: 322; Journal Issue: C; Journal ID: ISSN 0029-5493
Research Org:
Argonne National Lab. (ANL), Argonne, IL (United States); Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
USDOE National Nuclear Security Administration (NNSA); USDOE Office of Nuclear Energy (NE)
Country of Publication:
United States
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; 36 MATERIALS SCIENCE; fission gas behavior; light water reactor (LWR); rate theory; silicide fuels; steady-state operation
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1430002