A model describing intra-granular fission gas behaviour in oxide fuel for advanced engineering tools

The description of intra-granular fission gas behaviour is a fundamental part of any model for the prediction of fission gas release and swelling in nuclear fuel. In this work, we present a model representing the evolution of intra-granular bubbles in terms of bubble number density and average bubble size. The model considers the fundamental processes of single gas atom diffusion, gas bubble nucleation, bubble re-solution, and gas atom trapping at bubbles. The model is derived from a detailed cluster dynamics formulation, yet it consists of only three differential equations in its final form; hence, it can be efficiently applied in engineering fuel performance codes while retaining a physical basis. We discuss the improvements made in our model in comparison to previous models for intra-granular bubble evolution. We validate the model against experimental data, both in terms of bubble number density and average bubble radius. Lastly, we perform an uncertainty analysis, by propagating the uncertainties in the parameters to the model results.

PIZZOCRI Davide;  PASTORE Giovanni;  BARANI Tommaso;  MAGNI A.;  LUZZI Lelio;  VAN UFFELEN Paul;  PITTS S.A.;  ALFONSI A.;  HALES J.D.; 

2018-04-04

ELSEVIER SCIENCE BV

JRC108478

0022-3115,   

https://www.sciencedirect.com/science/article/pii/S0022311517315039?via%3Dihub,    https://publications.jrc.ec.europa.eu/repository/handle/JRC108478,   

10.1016/j.jnucmat.2018.02.024,