Short Communication: Observation of Initial Burst Release of Fission Gas from High-Burnup UO2 Nuclear Fuel During Thermal Transient

A system was developed and tested to provide a deeper understanding of the fission gas release kinetics from nuclear fuel during thermal transients. Pressure, temperature, spectral data, optical images were simultaneously collected resistive sample heating, all released gases in liquid nitrogen-cooled charcoal traps. Standup testing performed with high-burnup segment rod section an average local burnup 77 GWd/tU. During approximately 6 ± 2% generated inventory after ramp heating 460°C. Heating ceased when ejected holder, as observed by constant imaging.