Water droplet extractor for multistage turbine - uses guide vanes to impart swirling motion to steam for removing droplets centrifugally

摘要

The steam turbine has a high pressure section with three stages. After the steam has passed through these stages some of it has condensed to form droplets which are carried along with the steam flow. These droplets can erode the blades of the low pressure stages and so the steam is made to reverse its direction and flow between guide vanes in an annulus outside the high pressure casing. These guide vanes impart a swirl to the steam and the resultant centrifugal forces cause the water droplets to flow out through holes into the annulus.