The analysis of steam line breaks, feed line breaks and steam line breaks with tube rupture accidents all involve calculating the heat transfer, carryover and fall back on the secondary side of the steam generator during off-normal conditions. The work reported here has been done to fill this need. Based on the comparisons between the code predictions and the data obtained from the experiments conducted at Battelle-Frankfurt and at GE, the best drift flux model constants for various flow regimes are selected.
It is found that the measured dryout front is much higher than the calculated mixture level. If the effective heat transfer area is determined from the mixture level, the primary-to-secondary heat transfer will be substantially underpredicted.
From the result of the liquid hold-up study we would expect to find two mixture levels, one in the bottom of the steam generator and one above the top tube support plate, provided that flooding occurs at all.