Computational and Experimental Studies Substantiating Setups for Localizing Fast-Reactor Melted Fuel

Analysis of an unanticipated accident due to complete loss of system and autonomous power together with failure of the emergency protection of the reactor showed for BN-800 and -1200 that core meltdown does not occur. Nonetheless, core meltdown is postulated, even though the probability of such an event (residual-risk accident) is extremely low. In the event of an accident, core fragments move downwards, melting through the pressure-chamber structures and settling on a special retaining setup (bottom pan) located beneath the pressure chamber and intended for localizing the melted core fragments. To substantiate the construction, confirm the design characteristics of the apparatus intended for collecting and localizing the melted fuel computational and experimental studies were performed for the final stage of an unanticipated accident post-accident removal of the residual heat release from the fuel melt.