Validation of Post-Dryout Phenomena for the Space Code

Abstract

SPACE code which is based on a multi-dimensional two-fluid, three-field model is under development for the licensing calculation of pressurized water reactors. Unlike other major best-estimate nuclear reactor system analysis codes that have been developed based on a two-fluid six equation model, the field equations of SPACE code incorporates a dispersed liquid field in addition to vapor and continuous liquid fields. This model features a set of nine equations of mass, energy and momentum conservation. A dispersed liquid field is expected to be important in annular-mist and post-dryout conditions since a dispersed liquid field behaves differently with a continuous liquid field. This is the major reason to incorporate a dispersed liquid field as an additional liquid field. As a part of the validation effort of SPACE code, FLECHT-SEASET reflood problems have been assessed and are presented in this paper.