A novel integrated probe has been developed and has been applied to measure the amount of coarse water upstream and downstream of a newly designed stage in a model steam turbine, and also downstream of the last stage of a 350 MW low-pressure steam turbine. This paper presents the measurement principles of the probe and the measurement results in the two turbines. The measurements show that the velocity, flow direction, quantity and size of the coarse water droplets over the height of the blades cover a wide range. Based on this fact, a new way to reduce the size of coarse water droplets is proposed. Initial experiments using a model blade with a superhydrophilic surface coating confirmed that smaller droplets were formed.
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