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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.
J. Hope Forsmann
Nuclear Technology | Volume 193 | Number 1 | January 2016 | Pages 213-217
Technical Note | Special Issue on the RELAP5-3D Computer Code | doi.org/10.13182/NT14-141
Articles are hosted by Taylor and Francis Online.
To support the functionality of RELAP5-3D for best-estimate reactor simulation code, a variety of utility programs were developed at Idaho National Laboratory. Conversion and upgrades of RELAP5-3D to FORTRAN 95 required the upgrades of these utility programs as well. Pygmalion (Pygi) and the RELAP5-3D Graphical User Interface (RGUI) are two of the utility programs that were upgraded and enhanced.
Pygi creates a copy of a RELAP5-3D input file with updated initial condition information. From the restart/plot file of the RELAP5-3D run of an input deck, Pygi obtains the final conditions for each component. It creates a new input file that replaces the original input file values with updated conditions. This provides an accurate and efficient means of creating new input decks with steady-state input conditions.
RGUI is an alternative to the command line interface for performing RELAP5-3D–related work. RGUI provides single-interface access to other RELAP5-3D tools such as Pygi. It is highly configurable, allowing the user to customize the environment. The interface runs on both Linux and Windows.
This suite of utility programs is continually being enhanced to provide better support for RELAP5-3D users. This technical note provides details of Pygi and RGUI functionality. Future plans for enhancements are also included.
