Modelling of Severe Accident Phenomena in Level 2 PSA for Paks NPP

  • Zsolt Téchy
  • Gabor Lajtha
Conference paper


A Level 2 PSA study has recently been performed for the Paks NPP in Hungary. The probabilistic assessment of the containment loads is illustrated on the example of hydrogen combustion. Depending on the composition of the mixture the combustion mechanism could be either a turbulent deflagration or a deflagration-to-detonation transition (DDT). Hydrogen ignition as well as combustion and the associated pressure loads are described in probabilistic terms. The failure probability of the containment is calculated from pressure load and fragility distributions.


Pressure Load Fragility Curve Probability Density Distribution Hydrogen Combustion Severe Accident 
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Copyright information

© Springer-Verlag London 2004

Authors and Affiliations

  • Zsolt Téchy
    • 1
  • Gabor Lajtha
    • 1
  1. 1.VEIKI Institute for Electric Power Research Co.BudapestHungary

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