Measurement of wet steam in a 300 mw direct air cooling steam turbine

For study the wet steam flow in the direct air-cooling steam turbine, measurements were carried out in a 300MW turbine with a newly developed combined probe. The wetness in the direct air-cooling steam turbine is lower and varies not much along the blade height. Droplets size distribution and mean diameter are smaller too comparing to water-cooling steam turbine. The measured relative inner efficiencies of LP obtained by the probe agree well with the results obtained by thermal performance test.