Fission severe accidents, computer codes

Such approaches, which aim at the establishment of a single quantity to represent the fraction of the core inventory that would be released in the event of a severe reactor accident, have now been widely abandoned. As has been summarily described by Malinauskas and Kress (1991), currently fission product release is recognized to be both scenario- and plant-specific, and it has become necessary to replace simple release fractions by computer codes that couple release and transport with thermal-hydraulic aspects. In particular it has been realized that the timing of fission product release can be of great importance and that the releases... 

VICTORIA-92, a mechanistic computer code for analyzing severe nuclear reactor accidents, now contains models for release of fission products and control rod materials, chemical interactions (both equilibrium and nonequilibrium), aerosol physics, and transport. With the current suite of models, the code can be used to analyze a wide variety of accident scenarios. Validation studies to date have provided confidence in the current models. 

The SCDAP/RELAP5/M0D3 computer code is designed to describe the overall reactor coolant system (RCS) thermal-hydraulic response, core damage progression, and fission product release and transport during severe accidents up to the point of reactor vessel or system failure The... 

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