Predicted Irradiation Behavior Of U Sub 3 O Sub 8 Al Dispersion Fuels For Production Reactor Applications

Candidate fuels for the new heavy-water production reactor include uranium/aluminum alloy and U3O--Al dispersion fuels. The U3O--Al dispersion fuel would make possible higher uranium loadings and would facilitate uranium recycle. Research efforts on U3O8--Al fuel include in-pile irradiation studies and development of analytical tools to characterize the behavior of dispersion fuels at high-burnup. In this paper the irradiation performance of U3O8--Al is assessed using the mechanistic Dispersion Analysis Research Tool (DART) code. Predictions of fuel swelling and alteration of thermal conductivity are presented and compared with experimental data. Calculational results indicate good agreement with available data where the effects of as-fabricated porosity and U3O8--Al oxygen exchange reactions are shown to exert a controlling influence on irradiation behavior. The DART code is judged to be a useful tool for assessing U3O8--Al performance over a wide range of irradiation conditions. 8 refs., 8 figs., 1 tab.