High Burnup Transient Fission Gas Release Testing and Post-Test Examinations

Technical Report · Sun Jun 01 04:00:00 EDT 2025

DOI:https://doi.org/10.2172/3002384· OSTI ID:3002384

Harp, Jason M. ^[1]; Yan, Yong ^[1]; Baldwin, Charles A. ^[1]; Morris, Robert N. ^[1]; Jones, Matthew M. ^[1]; Han, Jae-Kyung ^[1]; Capps, Nathan A. ^[1]

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1. Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

The contribution of transient fission gas release (tFGR) to the burst behavior of high burnup fuel during a loss of coolant accident (LOCA) for commercial light water reactors is a complex phenomenon that is not fully understood. During the temperature ramp associated with a LOCA, there is significant additional transient fission gas release in excess of the steady state fission gas release from normal operation. An addition to the Oak Ridge National Laboratory Severe Accident Test Station (SATS) was created to explore the different conditions that impact transient fission gas release. Four tests on commercially irradiated zirconium clad uranium dioxide nuclear fuel were performed to support transient fission gas release study. These experiments and their post-test analyses are discussed. The first test on high burnup fuel revealed a LOCA relevant transient fission gas release of 5.3% for an unpressurised segment. Subsequent tests have measured transient fission gas release at different conditions that span from 4.8% to 14.4 % transient fission gas release.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 3002384
• Report Number(s): ORNL-TM--2025-3923
• Country of Publication: United States
• Language: English