New catalog on (U,PU)O2 properties for fast reactors and first measurements on irradiated and non-irradiated fuels within the ESNII + project.

Abstract

International audienceThe thermal conductivity is an important parameter for the assessment of the FBR fuel thermal behavior during irradiation. In this study, the effect of burn-up on the thermal conductivity of FBR MOX fuel is investigated experimentallly. The thermal diffuvitiy of FBR fuel with a burn-up of 13 at% was measured by the laser flash technique and the thermal conductivity was deduced. It is shown that the thermal conductivity is higher than could be predicted with correlations issued from LWR UO2 and MOX results. This effect is interpreted as being due to the diffusion of fission products out of the fuel matrix, leading to the formation of the JOG