Development of small, fast reactor core designs using lead-based coolant

摘要

A variety of small (100 MWe) fast reactor core designs are developed, these211u001einclude compact configurations, long-lived (15-year fuel lifetime) cores, and 211u001ederated, natural circulation designs. Trade studies are described which identify 211u001ekey core design issues for lead-based coolant systems. Performance parameters and 211u001ereactivity feedback coefficients are compared for lead-bismuth eutectic (LBE) and 211u001esodium-cooled cores of consistent design. The results of these studies indicate 211u001ethat the superior neutron reflection capability of lead alloys reduces the 211u001eenrichment and burnup swing compared to conventional sodium-cooled systems; 211u001ehowever, the discharge fluence is significantly increased. The size requirement 211u001efor long-lived systems is constrained by reactivity loss considerations, not fuel 211u001eburnup or fluence limits. The derated lead-alloy cooled natural circulation cores 211u001erequire a core volume roughly eight times greater than conventional compact 211u001esystems. In general, reactivity coefficients important for passive safety 211u001eperformance are less favorable for the larger, derated configurations.