Molten corium oxidation model

In order to model oxidation of Zr–O and U–Zr–O melts, post-test appearance of refrozen oxidised melts in the CORA and QUENCH bundle tests performed at the Research Centre Karlsruhe (FZK) are analysed. Furthermore, data from new separate effect tests on ZrO₂ crucible dissolution by molten Zry, specially designed for investigation of long-term behaviour during the melt oxidation stage, are taken into consideration. On this base, a new model on oxidation of molten Zr–O and U–Zr–O mixtures in steam was developed, which allows interpretation of melt oxidation and hydrogen production observed in various bundle tests. The complete formulation of the analytical model, development of the numerical model and its validation against the crucible tests are presented.