MOISTURE REMOVAL DEVICE FOR STEAM TURBINE

摘要

The purpose of the present invention is to improve the efficiency of removal of a water film flow that forms on a stator blade ventral surface and minimize the erosion of a rotor blade by performing simple machining of the stator blade. In this moisture removal device for a steam turbine, a hollow section (12a) is formed on the inside of a stator blade (12), a stator blade ventral surface (fs) that receives a wet steam flow (s) comprises an inlet opening (a), and a slit hole (22) that connects with the hollow section (12a) is formed in the axial direction of the stator blade (12). The hollow section (12a) is connected to an area having lower pressure than the flow site of the wet steam flow (s). Pressure is reduced in the hollow section (12a) and a water film flow (sw) that is formed by water droplets (dw) that adhere to the stator blade ventral surface (fs) is sucked into the slit hole (22). The slit hole (22) is formed on the downstream-side end of the hollow section (12a) in the flow direction of the wet steam flow (s) and the stator blade rear edge-side wall surface (22a) of the slit hole (22) is configured so as to form an acute angle with respect to a front edge-side reference surface of the stator blade ventral surface (fs). As a result, it is possible to place the inlet opening (a) on the stator blade rear edge (re) side.