Grain and bubble morphology in fission gas percolation networks

An Included Phase Model [1] has been developed to study the time-evolution of inter-granular fission gas bubbles in mixed oxide nuclear fuels with potentially heterogeneous micro-structures on an irregular grid of representative grains. Specifically, we investigate grain edge network percolation of fission gas bubbles. The intention of these simulations is to investigate how variance in material properties, both chemical and physical, contribute to fission gas accumulation and release in nuclear fuels. In this work, fission gas theory and results of extensive simulation are described. Recent developments to the model are expounded and future applications are explored. (author)