Effects of liquid-separation components on separation performance of a steam separator

A downscaled model of a steam separator is used to understand characteristics of swirling flow and to investigate the effects of geometry of separator components on separation performance. Main conclusions obtained are as follows. (1) Separation performance improves with the gas volume flux. However carry under, i.e. the weight percentage of entrained gas in the water leaving the separator, tends to be lower as the liquid film thickness becomes thinner under low liquid volume flux conditions. (2) The ratio of the flow rate of separated liquid to the total liquid flow rate does not depend on the liquid volume flux so much. On the other hand, the carryunder becomes lower with the liquid volume flux. (3) An improved pick-off ring, whose gap width is about the maximum liquid film thickness and sudden expansion is mitigated by a diffuser, effectively reduces the pressure drop while keeping high separation performance. (author)