AUTHOR=Li Yang , Gong Houjun , Hu Yunwen , Yang Shengxing , Li Yong , Zan Yuanfeng TITLE=Experimental Study on Stratification Morphology of the Molten Pool During Severe Accident JOURNAL=Frontiers in Energy Research VOLUME=Volume 9 - 2021 YEAR=2021 URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2021.813298 DOI=10.3389/fenrg.2021.813298 ISSN=2296-598X ABSTRACT=A stratification morphology of molten pool under severe reactor accident was investigated by the CESEF experimental facility. The experimental scale was 5000 g, the atomic ratio of U/Zr was 1.5, the content of stainless steel was 10%, and the oxidation degree of Zr was 40%~100%. It was shown that the molten pool was obviously stratified within the range of experimental parameters, one was metal layer, the other was oxide layer. The layered morphology of the molten pool was different with the composition of different corium. With the decreased of Zr oxidation degree, the metal layer moved downward in the molten pool, and the molten pool would overturn. The main element in the oxide layer was U, Zr, O, and the content of stainless steel was low. The main element in the metal layer was stainless steel and contained a certain amount of U and Zr.