Coupled Modeling and Simulation of Phase Transformation in Zircaloy-4 Fuel Cladding Under Loss-of-Coolant Accident Conditions
Under loss-of-coolant conditions, the temperature on fuel cladding will increase rapidly (up to 1000–1500 K), which will not only cause a dramatic oxidation reaction of Zircaloy-4 and an increase in hydrogen concentration but also cause an allotropic phase transformation of Zircaloy-4 from hexagonal...
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Frontiers Media S.A.
2021-06-01
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| Series: | Frontiers in Energy Research |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fenrg.2021.667419/full |
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| author | Wenjun Lu Libo Qian Wenzhong Zhou Wenzhong Zhou |
| author_facet | Wenjun Lu Libo Qian Wenzhong Zhou Wenzhong Zhou |
| author_sort | Wenjun Lu |
| collection | DOAJ |
| description | Under loss-of-coolant conditions, the temperature on fuel cladding will increase rapidly (up to 1000–1500 K), which will not only cause a dramatic oxidation reaction of Zircaloy-4 and an increase in hydrogen concentration but also cause an allotropic phase transformation of Zircaloy-4 from hexagonal (α-pahse) to cubic (β-phase) crystal structure. As we all know, thermophysical properties have a close relationship with the microstructure of the material. Moreover, because of an important influence of the phase transformation on the creep resistance and the ductility of the fuel rod, studying the crystallographic phase transformation kinetics is pivotal for evaluating properties for fuel rod completeness. We coupled the phase transformation model together with the existing physical models for reactor fuel, gap, cladding, and coolant, based on the finite element analysis and simulation software COMSOL Multiphysics. The critical parameter for this transformation is the evolution of the volume fraction of the favored phase described by a function of time and temperature. Hence, we choose two different volume fractions (0 and 10%) of BeO for UO2-BeO enhanced thermal conductivity nuclear fuel and zircaloy cladding as objects of this study. In order to simulate loss-of-coolant accident conditions, five relevant parameters are studied, including the gap size between fuel and cladding, the temperature at the extremities of the fuel element, the coefficient of heat transfer, the linear power rate, and the coolant temperature, to see their influence on the behavior of phase transformation under non-isothermal conditions. The results show that the addition of 10vol%BeO in the UO2 fuel decreased the phase transformation effect a lot, and no significant phase transformation was observed in Zircaloy-4 cladding with UO2-BeO enhanced thermal conductivity nuclear fuel during existing loss-of-coolant accident conditions. |
| first_indexed | 2024-12-22T03:02:00Z |
| format | Article |
| id | doaj.art-6ef1bb2d168943d987b97957416ca262 |
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| issn | 2296-598X |
| language | English |
| last_indexed | 2024-12-22T03:02:00Z |
| publishDate | 2021-06-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Energy Research |
| spelling | doaj.art-6ef1bb2d168943d987b97957416ca2622022-12-21T18:41:08ZengFrontiers Media S.A.Frontiers in Energy Research2296-598X2021-06-01910.3389/fenrg.2021.667419667419Coupled Modeling and Simulation of Phase Transformation in Zircaloy-4 Fuel Cladding Under Loss-of-Coolant Accident ConditionsWenjun Lu0Libo Qian1Wenzhong Zhou2Wenzhong Zhou3Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-Sen University, Zhuhai, ChinaNuclear Power Institute of China, Chengdu, ChinaSino-French Institute of Nuclear Engineering and Technology, Sun Yat-Sen University, Zhuhai, ChinaDepartment of Mechanical Engineering, City University of Hong Kong, Hong Kong, ChinaUnder loss-of-coolant conditions, the temperature on fuel cladding will increase rapidly (up to 1000–1500 K), which will not only cause a dramatic oxidation reaction of Zircaloy-4 and an increase in hydrogen concentration but also cause an allotropic phase transformation of Zircaloy-4 from hexagonal (α-pahse) to cubic (β-phase) crystal structure. As we all know, thermophysical properties have a close relationship with the microstructure of the material. Moreover, because of an important influence of the phase transformation on the creep resistance and the ductility of the fuel rod, studying the crystallographic phase transformation kinetics is pivotal for evaluating properties for fuel rod completeness. We coupled the phase transformation model together with the existing physical models for reactor fuel, gap, cladding, and coolant, based on the finite element analysis and simulation software COMSOL Multiphysics. The critical parameter for this transformation is the evolution of the volume fraction of the favored phase described by a function of time and temperature. Hence, we choose two different volume fractions (0 and 10%) of BeO for UO2-BeO enhanced thermal conductivity nuclear fuel and zircaloy cladding as objects of this study. In order to simulate loss-of-coolant accident conditions, five relevant parameters are studied, including the gap size between fuel and cladding, the temperature at the extremities of the fuel element, the coefficient of heat transfer, the linear power rate, and the coolant temperature, to see their influence on the behavior of phase transformation under non-isothermal conditions. The results show that the addition of 10vol%BeO in the UO2 fuel decreased the phase transformation effect a lot, and no significant phase transformation was observed in Zircaloy-4 cladding with UO2-BeO enhanced thermal conductivity nuclear fuel during existing loss-of-coolant accident conditions.https://www.frontiersin.org/articles/10.3389/fenrg.2021.667419/fullphase transformationzircaloy-4LOCAaccident tolerant fuel (ATF)fully coupled |
| spellingShingle | Wenjun Lu Libo Qian Wenzhong Zhou Wenzhong Zhou Coupled Modeling and Simulation of Phase Transformation in Zircaloy-4 Fuel Cladding Under Loss-of-Coolant Accident Conditions Frontiers in Energy Research phase transformation zircaloy-4 LOCA accident tolerant fuel (ATF) fully coupled |
| title | Coupled Modeling and Simulation of Phase Transformation in Zircaloy-4 Fuel Cladding Under Loss-of-Coolant Accident Conditions |
| title_full | Coupled Modeling and Simulation of Phase Transformation in Zircaloy-4 Fuel Cladding Under Loss-of-Coolant Accident Conditions |
| title_fullStr | Coupled Modeling and Simulation of Phase Transformation in Zircaloy-4 Fuel Cladding Under Loss-of-Coolant Accident Conditions |
| title_full_unstemmed | Coupled Modeling and Simulation of Phase Transformation in Zircaloy-4 Fuel Cladding Under Loss-of-Coolant Accident Conditions |
| title_short | Coupled Modeling and Simulation of Phase Transformation in Zircaloy-4 Fuel Cladding Under Loss-of-Coolant Accident Conditions |
| title_sort | coupled modeling and simulation of phase transformation in zircaloy 4 fuel cladding under loss of coolant accident conditions |
| topic | phase transformation zircaloy-4 LOCA accident tolerant fuel (ATF) fully coupled |
| url | https://www.frontiersin.org/articles/10.3389/fenrg.2021.667419/full |
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