Study of thermal conductivity influence on MOX fuel behaviour

The present paper summarizes the influence of different thermal conductivity correlations on MOX fuel rod behaviour. In this respect, different MOX thermal conductivity correlations selected from various open literature sources were compared with each other as well as with conductivity correlations adopted in the TRANSURANUS code used in the present work for evaluation of MOX fuel rod performances. After comparing the different correlations, we introduced those from the open literature in the TRANSURANUS code. In order to confirm their effect on the fuel performance parameters we simulated an experiment from the International Fuel Performance Experiments (IFPE) database, IFA597 MOX, and we analysed the results obtained with the code using all the studied thermal conductivities versus the measurements on the fuel temperature, internal pressure and fission gas release. We noticed that some of the correlations underestimate significantly the measurements. Further, in our study we used only those correlations giving nearest values to the measurements. As a final conclusion, we can notify that standard TRANSURANUS and Halden correlations are the most indicated to be used for this type of analysis. (authors)