OPTIMIZATION STUDIES ON PASTE-FUELED FAST REACTORS

The reference design is an unmoderated, sodium-cooled reactor using a paste fuel of uranium monocarbide in sodium. The core is a cylinder 5 ft in diameter and 5 ft in height. An 18-in. thick breeding blanket surrounds the core, and an 18-in. thick graphite reflector surrounds the blanket. Various changes were made in the reference core to uncover any possible modifications for cost reductions and to evaluate the consequences of certain design modifications which might occur. Cases were studied for variations in: fuel volume fraction in the core from 0.2 to 0.6; fertile material volume fraction in the blanket from 0.2 to 0.6; blanket thickness 3 in. to 24 in.; fuel materials of UC, U metal, UC/ sub 2/, PuC-- UC, Pu-- U metal, and PuO/sub 2/-- UC/sub 2/; and liquid carrier in the paste of Na, Sn, or Pb. (auth