Development of accident dose consequences simulation software for nuclear emergency response applications

This study integrated the nuclear power plant simulation software, PCTRAN, with the atmospheric puff model to efficiently evaluate a nuclear power plant accident and its offsite dose consequences. PCTRAN is a PC based simulation code with user-friendly interface, and is capable of running faster than real time. Accident initiation events can be activated in the software, and the radioactive materials may be released from the plant to the environment. To reduce the computational burden, the software developed in this study considers those radioactive materials are released at the end of every time interval, which is user-predetermined. Therefore, during the progression of the simulated transient or accident, puffs are sequentially generated and dispersed in all directions governed by the Pasquill stability category, wind velocity, and wind direction. The thyroid and whole body dose rates (and their accumulations) are shown as a color-shaded plot on the map at every spatial location within the emergency planning zone (EPZ). In this study, a postulated scenario was simulated to predict its dose consequences during the accident progression. All simulation results, such as the plant state parameters, the activation of control systems, the level of dose, and so on, are visualized in colorful and animated images on the interface. This study also demonstrates that PCTRAN executes the simulation faster than the accident time, so as to facilitate PCTRAN in the application of nuclear emergency response.