Oxidation effect on steel corrosion and thermal loads during corium melt in-vessel retention
2014 (English)In: Nuclear Engineering and Design, ISSN 0029-5493, E-ISSN 1872-759X, Vol. 278, 310-316 p.Article in journal (Refereed) Published
During a severe accident with core meltdown, the in-vessel molten core retention is challenged by the vessel steel ablation due to thermal and physicochemical interaction of melt with steel. In accidents with oxidizing atmosphere above the melt surface, a low melting point UO2+x-ZrO2-FeOy corium pool can form. In this case ablation of the RPV steel interacting with the molten corium is a corrosion process. Experiments carried out within the International Scientific and Technology Center's (ISTC) METCOR Project have shown that the corrosion rate can vary and depends on both surface temperature of the RPV steel and oxygen potential of the melt. If the oxygen potential is low, the corrosion rate is controlled by the solid phase diffusion of Fe ions in the corrosion layer. At high oxygen potential and steel surface layer temperature of 1050 degrees C and higher, the corrosion rate intensifies because of corrosion layer liquefaction and liquid phase diffusion of Fe ions. The paper analyzes conditions under which corrosion intensification occurs and can impact on in-vessel melt retention (IVR).
Place, publisher, year, edition, pages
2014. Vol. 278, 310-316 p.
Energy Engineering Other Physics Topics
IdentifiersURN: urn:nbn:se:kth:diva-156447DOI: 10.1016/j.nucengdes.2014.07.034ISI: 000343839300031ScopusID: 2-s2.0-84906847884OAI: oai:DiVA.org:kth-156447DiVA: diva2:767795
QC 201412022014-12-022014-11-282014-12-02Bibliographically approved