Dropwise condensation of steam over a bundle of tubes at utility turbine condenser pressure

Bundles of in-line, titanium tubes have been tested in filmwise and dropwise condensation modes. They were tested with pure steam and with steam-air mixtures at conditions typical of a turbine condenser. The overall, heat-transfer coefficients against bundle position are presented. They show the expected behaviour for filmwise condensation but reveal that the dropwise, heat-transfer coefficient does not vary significantly throughout the bundle when condensing pure vapours. Air is shown to decrease the dropwise, heat-transfer coefficient but not dissimilarly from that occurring in filmwise condensation. The findings indicate that dropwise condensation could produce real savings if it can be applied to turbine condensers.