Applications of the United States Nuclear Regulatory Commission Nuclear Plant Analyzer

摘要

The Nuclear Plant Analyzer (NPA) is being developed as the US NRC's state of the art safety analysis and engineering tool to address key nuclear plant safety issues. The NPA integrates the NRC's computerized reactor behavior codes such as RELAP5 and TRAC-BWR, both of which are well-developed computer graphics programs and large repositories of reactor design and experimental data. Utilizing these complex reactor behavior codes, as well as the experiment data repositories, enables simulation applications of the NPA that are generally not possible with more simplistic, less mechanistic reactor behavior codes used in training simulators or with simulators that are limited to displaying calculated data only. This paper describes four applications of the NPA simulation capabilities in assisting reactor safety analyses. Two analyses evaluated reactor operating procedures, during off-normal operation, for a pressurized water reactor (PWR) and a boiling water reactor (BWR), respectively. The third analysis was performed in support of a reactor safety experiment conducted in the Semiscale facility. The final application demonstrated the usefulness of atmospheric dispersion computer codes for site emergency planning purposes. An overview of the NPA simulation capabilities and how it supported these analyses are the topics of this paper. (ERA citation 09:040159)