|About this Abstract
||2023 TMS Annual Meeting & Exhibition
||Ceramic Materials for Nuclear Energy Research and Applications
||Simulation of irradiation-induced bubble over-pressurization and application in fuel performance
||Michael Cooper, Christopher Matthews, Larry Aagesen, Chris Stanek, David Andersson
|On-Site Speaker (Planned)
It is thought that over-pressurized bubbles (in excess of the equilibrium pressure) play an important role in the susceptibility of UO2 high burnup structure (HBS) to pulverization. Cluster dynamics show that under irradiation, the dominant diffusion mechanism for U and Xe changes at low temperature compared to at high temperatures. The results indicate that irradiation-induced interstitial diffusion plays a role in bubble over-pressurization in the cooler periphery of the pellet where HBS forms. The bubble pressure is relieved by the emission of dislocation loops or by the driving force for the interstitial-bubble reaction tending to zero at high pressures. Here, we present the results of molecular and cluster dynamics simulations exploring diffusion mechanisms at low temperatures and their impact on bubble pressure. The introduction of such diffusion mechanisms into the physics-based fission gas model in BISON has also been carried out to improve the predicted bubble pressure and morphology evolution.
||Ceramics, Nuclear Materials,