Abstract

The pressure-flow characteristics of a Zobel-type vortex diode have been measured using a working fluid of compressible wet steam. Tests using superheated steam with inlet/outlet pressure ratios across the diode of up to 30 have shown clearly the effects of compressibility and choking on the diode characteristics. Repeating the tests using wet steam, with known dryness fractions, has shown separately the effects of wetness on the diode performance. When the diode was installed into the pipwork in the high-resistance direction, excessive steam wetness (quality <0.93) led to a build-up of water and when this was eventually swept through to the diode the resistance was seen to fall substantially as the strong internal vortex was destroyed. © 1987.