Critical experiments and analysis on the light water moderated plutonium dioxide-uranium dioxide lattices, (8)

When recycle plutonium fuel is loaded partially in a light water-moderated power reactor, the increase of power peaking factor due to the difference in nuclear characteristics between plutonium and uranium is important in reactor design and operation. The JPDR mock-up cores to study on this subject were built in JAERI, and the power distributions were measured to obtain the power peaking factors. The core consists of 3.0 wt. % plutonium oxide-uranium oxide, 2.6 wt. % uranium oxide, a control rod, a follower and poison curtains. Four plutonium assemblies loaded in the core center are surrounded by uranium ocide assemblies. The results will be useful for the design of the plutonium enrichment distribution in plutonium oxide-uranium oxide fuel assemblies. (Mori, K.)