Rate theory scenarios study on fission gas behavior of U3Si2 under LOCA conditions in LWRs

• Published in: Nuclear engineering and design Vol. 326; pp. 371 - 382
• Main Authors: Miao, Yinbin, Gamble, Kyle A., Andersson, David, Mei, Zhi-Gang, Yacout, Abdellatif M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.01.2018; Elsevier BV
• Subjects: Behavior; Buffalo; Computer simulation; Density; Density functional theory; Fission; Fission gas behavior; Fuels; Ion irradiation; Irradiation; Light water reactor (LWR); Light water reactors; Loss of coolant accidents; Loss-of-coolant accident (LOCA); Nuclear fuels; Radiation; Rate theory; Reactors; Silicide fuels; Steady state; Studies; Uranium silicide; Silicide fuels; Rate theory; Loss-of-coolant accident (LOCA); Fission gas behavior; Light water reactor (LWR)
• ISSN: 0029-5493; 1872-759X
• DOI: 10.1016/j.nucengdes.2017.11.034

•Rate theory fission gas model for U3Si2 was developed for power transients in LWRs.•Model parametrization was conducted based on experimental and computational data.•Multiple possible microstructure models were taken into consideration.•Fission gas behavior was simulated based on the BISON-predicted LOCA parameters.•A comprehensive scenarios study was performed to provide conservative evaluations. Fission gas behavior of U3Si2 under various loss-of-coolant accident (LOCA) conditions in light water reactors (LWRs) was simulated using rate theory. A rate theory model for U3Si2 that covers both steady-state operation and power transients was developed for the GRASS-SST code based on existing research reactor/ion irradiation experimental data and theoretical predictions of density functional theory (DFT) calculations. The steady-state and LOCA condition parameters were either directly provided or inspired by BISON simulations. Due to the absence of in-pile experiment data for U3Si2’s fuel performance under LWR conditions at this stage of accident tolerant fuel (ATF) development, a variety of LOCA scenarios were taken into consideration to comprehensively and conservatively evaluate the fission gas behavior of U3Si2 during a LOCA.