Water boiling time in a spent fuel pool with adiabatic and non-adiabatic boundary conditions

DE FARIA, FERNANDO PEREIRA; GODINO, DARIO MARTIN; CORZO, SANTIAGO FRANCISCO; RAMAJO, DAMIÁN ENRIQUE; COSTA, ANTONELLA LOMBARDI; LIMA, CLÁUBIA PEREIRA BEZERRA

Brazilian Journal of Development

Brazilian Journals Publicações de Periódicos e Editora Ltda

Lugar: Curitiba; Año: 2022 vol. 8 p. 61116 - 61125

The Spent Fuel Pool (SFP) of Angra II, from Brazil, has received standard spent fuel (SF) assemblies of Uranium dioxide (UO2) discharged from Pressurized Water Reactors (PWR) of the Nuclear Power Plants (NPP) of Angra since the beginning of its operation. However, in case of using Mixed Oxide (MOX) or Thorium-based fuels, it would require further thermal studies of wet storage. It includes the determination of the water boiling time (Tb) of the SFP in case of breakdown of its external cooling system (ECS). This work presents studies of Tb of a simulated SFP storing mixed SF discharged from PWRs. The types of mixed SF studied include MOX plus UO2, oxide of thorium/uranium (U-Th)O2 plus UO2, and oxide of Thorium/transuranic (TRU-Th)O2 plus UO2. The simulations were implemented in CFX Ansys considering the top of the SFP as eitheradiabatic or non-adiabatic wall. Tb is considerably higher when the non-adiabatic boundary condition is used.