Contribution to the steam water separation at HP turbine

A Chevron type separator was developed and tested by Skoda, The Research Institute of Power Engineering, designed for use with horizontal moisture reheaters SPP 1000 of the 1000 MW unit in the Temelin nuclear power plant. It uses two principal processes, viz., a mechanical separation of droplets from the saturated steam flow on curved streamlines taking place when the droplets impinge on the separator walls or are carried to the drainage channel region, and a secondary separation process when the critical entrainment velocity is exceeded. A theoretical calculation showed that the channel design could secure complete capture of droplets from the saturated steam in the high-pressure exhaust. The channel with drainage facilities was shown to provide improved separation, especially for very small droplets. The increased pressure drop in the separation channel, however, caused droplet entrainment directly from the drainage chamber. Experimental tests of the separator model were performed using a water-air test rig for the above-critical range of inlet velocities. (M.D.). 3 figs., 2 refs