Characteristic features of the development of serious unanticipated accidents in RBMK reactors and approaches to controlling such accidents

The basic structural features of RBMK reactor systems (absence of an overall external protective shell, disintegrating nature of the circulation loop, multichannel nature of the core, positive steam coefficient of reactivity, large mass of the high-heat-capacity graphite moderator), which predetermine the development of postulated serious unanticipated accidents and their control, are examined. Categories of core behavior for unanticipated accidents and types of accidents resulting in a definite type of damage are determined. The character of the flow of typical unanticipated accidents, possible approaches to controlling the consequences of accidents, and means for performing computational analysis of unanticipated accidents are examined.