MIGRATION OF THO2 KERNELS UNDER INFLUENCE OF A TEMPERATURE-GRADIENT

These studies were conducted to obtain descriptions of migration rates that will be used in core design studies to evaluate the impact of ThO//2 migration on fertile fuel performance in an operating HTGR and to define characteristics needed by any comprehensive model describing ThO//2 kernel migration. The kinetics data generated in these postirradiation studies are consistent witn in-pile data collected by investigators at Oak Ridge National Laboratory, which supports use of the more precise postirradiation heating results in HTGR core design studies. This work will contribute to an optimization of HTGR core design and an increased confidence in fuel performance predictions.