Representative experiments on nuclear meltdowns

Nuclear meltdown accidents and the possibility of specific countermeasures have formed the focal point of discussions on reactor safety for ten years now, particularly following the events in Tschernobyl. One of these counter measures is - assuming failure of the reactor pressure vessel - wide-area e x-vessel spreading of the meltdown product in a catchment system with subse quent water flooding. This proposed method corresponds to the current plann ing basis for the Franco-German Joint Project EPR. Since 1993, a German wor king group has been carrying out research into the control of nuclear meltd owns: experiments with nuclear meltdown products, it is hoped, will provide information for the control of nuclear meltdown accidents. An exceptional feature of these investigations is the realisability of large-scale experim ents with prototypal corium-combinations and representative test conditions . The present article describes the setting-up and the results of the COMAS (Corium on Metal Surfaces)-spreading experiment and of the CORESA (Corium on Refractory and Sacrificial Materials)test program in the commercial-scal e radioactive meltdown system CARLA.