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The human factor in licensing and operating the next generation of nuclear plants
As human factors specialists working at the intersection of human performance and nuclear operations, we are witnessing one of the nuclear sector’s most significant transitions in decades. The emergence of small modular reactors, microreactors, and other advanced designs is reshaping the industry’s landscape. Digital instrumentation and controls, passive safety systems, and increased automation are creating opportunities for greater safety margins and more flexible operation. These same features also fundamentally redefine what it means to “operate” a nuclear plant. Interactions among human roles, automation, and passive systems shape how people maintain awareness, exercise judgment, and intervene when necessary. These developments affect both operational realities and the regulatory foundations on which nuclear safety is built.
Sadayuki Izutsu, Yoshiro Kudo, Junichi Onuma, Tomohiko Iwasaki, Sakae Muto, Akio Toba
Nuclear Technology | Volume 89 | Number 1 | January 1990 | Pages 92-102
Technical Paper | Nuclear Safety | doi.org/10.13182/NT90-A34361
Articles are hosted by Taylor and Francis Online.
Rod drop accidents (RDAs) were calculated for a typical 1100-MW(electric) boiling water reactor (BWR) using the three-dimensional core dynamics simulation code ARIES. Calculated cases are for cold start-up and hot standby cores. In both cold start-up and hot standby core RDAs, the moderator density reactivity feedback has an important effect on suppressing fuel enthalpy increase. Hot standby core RDAs, in particular, show remarkable effects of the moderator density reactivity feedback on reducing the power peak and succeeding fuel enthalpy rise. Sensitivity analyses of the effects of initial power level, core inlet subcooling, rod drop speed, dropping rod worth, etc., have been carried out under both cold start-up and hot standby core conditions for a typical 1100-MW(electric) BWR. In the hot standby core RDAs, the parameters affecting neutronic conditions (such as Doppler feedback) and moderator density proved to be very sensitive. In the cold start-up core RDAs, the parameters affecting moderator density are not so sensitive, but the parameters affecting Doppler feedback or neutronic conditions proved to be more sensitive than in the hot standby core RDAs.
