A process model for fast prediction of radioactive releases from LWR.
K. Herviou, ICONE 8, 8ème international conference on nuclear engineering, 2-6 avril 2000, Baltimore USA.
The process model developed for the STEPS system is presented in the paper. This system is used for the faster than real-time prediction of the radioactivity released into the environment in case of an emergency situation in a light water reactor. At first the concepts are presented shortly. The accident scenarios in different plants are considered in order to set the background. The concept for the lumped thermohydraulic models is presented and the principal equations used are presented. The detailed core model is described and the radioactivity release and transport model related to the core model are described as well. After that the validation work for the Loviisa VVER , the Westinghouse PWR and the Olkiluoto BWR plant are described by comparison of the STEPS results with the predicition of more detailed codes like SMABRE and MELCOR.