Irradiation behavior analyses of oxide fuel pin for sodium-cooled fast reactors

Mizuno, Tomoyasu; Koyama, Shinichi  ; Kaito, Takeji ; Uwaba, Tomoyuki ; Tanaka, Kenya

A mixed oxide fuel pin concept with annular pellets and an oxide dispersion strengthened martensitic steel (ODS) cladding is a possible driver fuel for commercialized Sodium-cooled fast reactor (SFR) core. The capability of annular MOX fuel pins with (U,Pu) oxide fuel and Am bearing oxide fuel under a high burnup condition was evaluated by a fuel performance analysis code CEDAR developed in JAEA. The fuel temperature profiles, fuel and cladding deformation profiles, and radial temperature distribution at EOL were evaluated. Those results show that the fuel pin had enough safety margin to fuel melting under the irradiation. Also, the profiles of pressure on the cladding inner surface and the cladding deformation after irradiation were evaluated. Those results show that the gap of the fuel pin at fabrication had enough width not to occur the considerable fuel-cladding mechanical interaction (FCMI).