Containment atmosphere stratification during severe accidents. Results of HDR and DEMONA experiments

Experimental results from containment experiments performed in the HDR and DEMONA programmes are discussed. The findings of these experiments can be directly applied to real accident situations in a containment, either in a qualitative or in a quantitative manner. On the other hand, the HDR and DEMONA results provide a sound data basis for verification and further development of computer codes. These codes then can be used to reliably predict the distribution of the components of a containment atmosphere during a severe accident and the resulting consequences for the further course of the accident, or the efficiency of any countermeasures considered. (orig./HP)