Integral experiment on erbia-loaded thermal spectrum cores using Kyoto University Critical Assembly

摘要

Within the framework of Erbia bearing Super High-Burnup (Er-SHB) fuel development program, a series of critical experiments have been performed at Kyoto University Critical Assembly aiming at accumulation of basic neutronic properties of Erbia-loaded, low-enriched thermal spectrum cores. Three critical configurations having different averaged enrichment and erbia content have been constructed. Criticality, reactivity worth of erbia sample plate and other nuclear characteristics have been measured. Measurement of the erbia sample worth, defined as reactivity induced by substituting erbia plate with graphite plate, have been extensively carried out. Analyses of the experiment have been carried out using probabilistic and deterministic methods, and it has been shown that the prediction accuracy of erbia-loaded thermal spectrum cores is quite satisfactory by using the present cross section data libraries.