ADVANCED NEUTRON SOURCE ENRICHMENT STUDY

A study has been performed of the impact on performance of using low-e nriched uranium (20% U-235) or medium-enriched uranium (35% U-235) as an alternative fuel for the Advanced Neutron Source, which wa initiall y designed to use uranium enriched to 93% U-235. Higher fuel densities and larger volume cores were evaluated at the lower enrichments in te rms of impact on neutron flux, safety, safeguards, technical feasibili ty, and cost. The feasibility of fabricating uranium silicide fuel at increasing material density was specifically addressed by a panel of i nternational experts on research reactor fuels. The most viable altern ative designs for the reactor at lower enrichments were identified and discussed. Several sensitivity analysis were performed to gain an und erstanding of the performance of the reactor at parametric values of p ower, fuel density, core volume, and enrichment that were interpolatio ns between the boundary values imposed on the study or extrapolations from known technology.