Analyses of subcooled CCFL tests for evaluation of WCOBRA/TRAC applicability

The WCOBRA/TRAC-MOD7A, Rev. 1 code is currently licensed for best estimate large break LOCA analyses of 3 and 4 loop PWRs with emergency core cooling system injection located in the cold legs. As a part of the licensing effort to extend the code applicability to an upper plenum injection plant, the codes ability to predict subcooled flooding on a perforated plate was assessed by analyses of GE counter current flow limit tests and by comparison to the Bankoff flooding correlation (Bankoff et al. (1981)). The observed code model bias for subcooled CCFL can be eliminated by applying multiplication factors to the interfacial condensation and the interfacial drag models. (orig.)