Discrete element method study of fuel relocation and dispersal during loss-of-coolant accidents

Research output: Contribution to journalArticle

Institutes & Expert groups

Documents & links

Abstract

The fuel fragmentation, relocation and dispersal (FFRD) during LOCA transients today retain the attention of the nuclear safety community. The fine fragmentation observed at high burnup may, indeed, affect the Emergency Core Cooling System performance: accumulation of fuel debris in the cladding ballooned zone leads to a redistribution of the temperature profile, while dispersal of debris might lead to coolant blockage or to debris circulation through the primary circuit. This work presents a contribution, by discrete element method, towards a mechanistic description of the various stages of FFRD. The fuel fragments are described as a set of interacting particles, behaving as a granular medium. The model shows qualitative and quantitative agreement with experimental observations, such as the packing efficiency in the balloon, which is shown to stabilize at about 55%. The model is then applied to study fuel dispersal, for which experimental parametric studies are both difficult and expensive.

Details

Original languageEnglish
Pages (from-to)322-332
JournalJournal of Nuclear Materials
Volume478
DOIs
Publication statusPublished - 26 May 2016

Keywords

  • study, fuel relocation, Dispersal, loss of coolant, accidents

ID: 2061064