Extended validation of a developing post-dryout heat transfer correlation over a wide range of pressure conditions

The present paper deals with the validation of a post-dryout heat transfer correlation, which has been proposed by Nguyen and Moon (2015), to show its extended applicability to developing post-dryout region. It is also shown that the well-known film-boiling look-up table (LUT) method currently having limited application to fully-developed flow can be improved to extend its applicability to the developing post-dryout region. In order to show that the correlation can be utilized for nuclear reactor safety analysis, eight different sets of post-dryout data covering flow conditions both in both large break loss-of-coolant accident (LB LOCA) and prolonged station blackout (SBO) scenarios have been assessed. It turns out that the correlation predicts well the measured wall temperature with a total average error of 3.81% and a root-mean-square error of 13.46% in case of given CHF (dryout) condition. The prediction accuracy of the correlation is strongly influenced by how well the local vapor temperature and the CHF locations can be predicted.