On the prediction of the reactor vessel integrity under severe accident loadings (RPVSA)
In order to allow more reliable predictions on the lower head response under core meltdown conditions, the temperature distribution has been analysed including the natural convection in the corium pool. The mechanical models and the failure criteria have been improved based on the RUPTHER and FASTHER experiments, where typical temperature gradients are simulated. Lower head local melting as well as corium crust development have been addressed in the CORVIS experiment studying the contact between an alumina/iron thermite and a thick steel plate. The upper head loading by corium impact due to a postulated in-vessel steam explosion has been investigated by the BERDA experiment. Similarity rules were considered such that the results can be directly converted to reactor conditions. Based on these investigations, admissible steam explosion energy releases are determined which an upper head can carry. If these limits are not exceeded the reactor containment cannot be endangered by broken head fragments. To provide the necessary basic data, mechanical material tests have been performed.
Bibliographic Reference: An article published in: Nuclear Engineering and Design, 209 (2001) pp. 117-125
Record Number: 200214293 / Last updated on: 2002-01-28
Original language: en
Available languages: en