Fuel element behaviour in accident conditions. Introduction to the research program of the PNS

The relevant phenomena, such as can deformation and ability to cool, oxidation and embrittlement of Zircaloy cans and the interaction between the can and the fuel can be understood and described quantitatively in the whole temperature range between normal operation and core melt-out. The PNS investigations referred to the understanding of the relevant failure mechanisms of LWR fuel rods and the preparation of experimentally verified computer models for realistic accident analyses. The determination of the extent of the damage in the reactor core, the examination of the damage due to fission product release and the quantifying of safety factors were of special importance. (DG)