NC simulation in PWR and WWER-440 ITF

The applications of system codes have been of help for interpreting the experimental scenarios, for optimizing the features of the nodalizations and for characterizing the code capabilities. A list of significant achievements is given below together with references where details of the analyses can be found. 

Stable reflux condensation with liquid flowing counter-current to steam in the hot legs flow-rate is sufficient to remove core power till loop mass inventory achieves values as low as 30-40% of the nominal values  

Natural circulation with part of core rods in dry-out condition not favorable from the current technological and safety point of view. 

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