Simultaneous dissolution of UO_2 and ZrO_2 by molten zircaloy. New experiments and modelling

This report summarises the Tasks WP2.1 and WP7.3 of the COLOSS project (core loss during severe accident) within the 5"t"h Framework Programme of EU. The experimental task WP2.1 was performed during 2000-2002 at the RIAR (Dimitrovgrad, Russia) in collaboration with Forschungszentrum Karlsruhe. Whereas RIAR acted as a subcontractor to JRC/IE (Joint Research Centre, Petten). The analytical task WP7.3 was performed at the Nuclear Safety Institute (IBRAE) of Russian Academy of Sciences (RAS), with IBRAE acting as a subcontractor to JRC. The main objective of the task WP2.1 was to extend the experimental work packages on dissolution of UO_2 and ZrO_2 by molten Zry, started within the framework of the CIT project (4"t"h FP of EU) at Forschungszentrum Karlsruhe and AECL (Canada). The main objective of the task WP7.3 was to develop a model for the code SVECHA (mechanistic code to study a single rod behaviour) for analytical treatment of these phenomena. Final interpretation of the experimental results was performed jointly by JRC Petten, Forschungszentrum Karlsruhe, RIAR Dimitrovgrad and IBRAE Moscow. (orig.) / Available from TIB Hannover: ZA 5141(6947) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische Informationsbibliothek / SIGLE / DE / Germany