Status and first results of the BWR control blade degradation test under steam-starved conditions

Pshenichnikov, A.; 山崎 宰春; 永江 勇二; 倉田 正輝

no journal, , 

The present study is focused on the issue of a control blade degradation, which is the first step during BWR severe accidents. In particular problem of heterogeneous core degradation, boron behaviour, control blade liquefaction and melt relocation were analysed. Melt relocation features: onset, progress, candling, blockage formation and its subsequent melting was directly observed in situ using video cameras. Carefully tailored experimental conditions of the CLADS-MADE-01 test, which include preliminary oxidation, transient heating and long steam starvation phase, enabled successful reproducing of an accident scenario close to one that assumed to happen at Fukushima-1 Unit 2.