Deformation and damage of nuclear power station fuel elements under cyclic loading

• Published in: Journal of strain analysis for engineering design 2019-07, Vol.54 (5-6), p.348-359
• Main Authors: Breslavsky, Dmitry, Chuprynin, Aleksandr, Morachkovsky, Oleg, Tatarinova, Oksana, Pro, Will
• Format: Article
• Language: English
• Subjects: Acceleration; Asymptotic methods; Asymptotic series; Constitutive equations; Constitutive relationships; Cyclic loads; Deformation; Finite element method; Internal pressure; Nuclear fuel elements; Nuclear fuels; Nuclear power plants; Radiation damage; Shells of revolution
• ISSN: 0309-3247; 2041-3130
• DOI: 10.1177/0309324719874923

Deformation and damage of nuclear power station fuel element shells under irradiation and cyclic loading due vibrations are studied. Constitutive equations include dependencies for a creep-damage equation with a scalar damage parameter, as well as terms for thermal and irradiation creep strains, elastic, thermal, and swelling strains. The acceleration of the creep-damage process due to cyclic variation of internal pressure is considered with a dynamic creep model, for which constitutive equations are derived using the method of asymptotic expansions and averaging over a period of cyclic loading. Stress and strain states in the fuel element shell are determined by use of an in-house finite element method creep-damage code for shells of revolution. Results show the essential variation in the initially symmetric fuel element shell form, as well as the acceleration of creep-damage processes due to the cyclic pressure.