AUTHOR=Zeng Zitao , Pan Yongyu , Chen Xi , Zhang Chunyu , Yin Chunyu , Gao Shixin , Zhou Yi , Zhang Jie , He Xiujie , Yuan Cenxi 

TITLE=Three-Dimensional Modeling of Thermal-Mechanical Behavior of Accident Tolerant Fuels

JOURNAL=Frontiers in Energy Research

VOLUME=9

YEAR=2021

URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2021.636502

DOI=10.3389/fenrg.2021.636502

ISSN=2296-598X

ABSTRACT=<p>Considering the safety issues of the traditional UO<sub>2</sub>-Zr fuel, a variety of accident-tolerant fuel (ATF) candidates have been proposed in recent years. Among the several ATFs, U<sub>3</sub>Si<sub>2</sub>, and UN are the two promising candidates for fuel materials owing to their high thermal conductivity and high uranium density. The FeCrAl alloy and the SiC/SiC composite material are the two promising candidates for cladding owing to their high oxidation resistance and high strength. In order to quantitatively evaluate the performance of ATFs, this study summarizes the physical models of typical ATF cladding materials (FeCrAl and SiC) and pellet materials (UN and U<sub>3</sub>Si<sub>2</sub>). Then a three-dimensional non-linear finite element method is applied to simulate the thermal-mechanical behavior of several typical fuel-cladding combinations, including UO<sub>2</sub>-FeCrAl, UN-FeCrAl, U<sub>3</sub>Si<sub>2</sub>-FeCrAl, U<sub>3</sub>Si<sub>2</sub>-Zr, and U<sub>3</sub>Si<sub>2</sub>-SiC. The important physical quantities, such as the fuel centerline temperature, the deformation of the pellet and the cladding as well as the pellet-cladding mechanical interaction (PCMI) were studied. The fission gas release model was also verified and improved.</p>