Characteristics and Mechanisms of Debris Bed Formation Behavior in Severe Accidents of Sodium-Cooled Fast Reactors: Experimental and Modeling Studies

A Sodium-cooled Fast Reactor (SFR) is one of the optimized candidates in Generation IV nuclear reactor systems, but safety an essential issue for SFR development and application. Most knowledge was accumulated through investigations, especially Core Disruptive Accidents (CDAs). During CDA SFRs, molten materials core region are likely to discharge into subcooled sodium form a debris bed on lower vessel. Noticing that elaboration characteristics mechanisms Debris Bed Formation (DBF) behavior should be subsequent analysis coolability accident progression various experimental modeling studies, much obtained during past decades. Motivated promote future investigations CDAs previous experiments studies DBF systematically reviewed discussed this paper. The results showed flow-regime accumulated-bed were influenced by varying parameters realistic conditions. Through several empirical models proposed predicting flow regime DBF. In addition, further research, prospects concerning also described.