||A modeling study of the chemical reactions of beryllium/beryllide pebbles with steam for hydrogen safety design of fusion DEMO
中村, 誠 ,
金, 宰煥 ,
中道, 勝 ,
染谷, 洋二 ,
飛田, 健次坂本, 宜照
Water-cooled pebble-bed (WCPB) blanket, in which beryllium/beryllide in a pebble form is used, is one of blanket concepts based on present or near-term technology for fusion reactor. Combination use of water, as coolant, and beryllium/beryllide, as neutron multiplier, may pose a critical safety problem, i.e. the chemical reactivity of the beryllium/beryllide pebble and the hazard of the reaction-produced hydrogen. We present a new phenomenological model of the reaction behaviors of the beryllium/beryllide pebble with the steam. We have developed a code PSYCHE to numerically solve the model equations. The simulation results have been found to agree with the experimentally observed amount of the reaction-produced hydrogen. We also show a safety analysis of the transient behavior of the Be and Be12Ti pebbles in an in-box LOCA, i.e. loss-of-coolant accident in a blanket box.
Plasma Conference 2017 (PLASMA2017)