Abstract: A steam turbine in an embodiment includes a casing, a turbine rotor, a rotor blade cascade, a stationary blade cascade, and a spray unit, the rotor blade cascade and the stationary blade cascade being each arranged at a plurality of stages alternately in an axial direction of the turbine rotor. The turbine rotor is housed inside the casing. In the rotor blade cascade, a plurality of rotor blades are arranged in a circumferential direction of the turbine rotor. In the stationary blade cascade, a plurality of stationary blades are arranged in the circumferential direction of the turbine rotor between a diaphragm inner ring and a diaphragm outer ring. The spray unit sprays spray water to a space located upstream from a rotor blade cascade at a final stage among the rotor blade cascades at the plurality of stages inside the casing.

Abstract: An erosion resistant material has a continuous portion and discontinuous portions. The continuous portion has a continuous structure. The discontinuous portions are arranged inside the continuous portion to have a discontinuous structure. The discontinuous portions are formed of particles having an average particle diameter of 1 ?m or less. Further, the discontinuous portions are formed of a material having a surface hardness and a Young's modulus higher than those of the continuous portion.

Abstract: A steam turbine 10 according to an embodiment includes rotor blades 22 implanted to a turbine rotor 21, stationary blades 26 making up a turbine stage together with the rotor blades 22, diaphragm outer rings 23 including an annular extending part 24 surrounding a periphery of the rotor blades 22, and supporting the stationary blades 26, and diaphragm inner rings 25 supporting the stationary blades 26. The steam turbine 10 further includes an annular slit 40 formed at an inner surface of the diaphragm outer ring 23 between the stationary blades 26 and the rotor blades 22 along a circumferential direction, and communication holes 50 provided in plural at an outer surface of the diaphragm outer ring 23 along the circumferential direction, communicated to the annular slit 40 from the outer surface side, and communicated to an exhaust chamber sucking water films via the annular slit 40.

Abstract: A sealing device for a turbine has a sealing member provided in a gap between a rotor and a stator arranged to surround the rotor, and a fluid path provided within the stator, to introduce, into the stator, a cooling medium used to cool stationary blades extending radially inward from the stator, and to flow the cooling medium at least to an upstream side of the sealing member.

Abstract: An erosion resistant material has a continuous portion and discontinuous portions. The continuous portion has a continuous structure. The discontinuous portions are arranged inside the continuous portion to have a discontinuous structure. The discontinuous portions are formed of particles having an average particle diameter of 1 ?m or less. Further, the discontinuous portions are formed of a material having a surface hardness and a Young's modulus higher than those of the continuous portion.

Abstract: A steam turbine in an embodiment includes a casing, a turbine rotor, a rotor blade cascade, a stationary blade cascade, and a spray unit, the rotor blade cascade and the stationary blade cascade being each arranged at a plurality of stages alternately in an axial direction of the turbine rotor. The turbine rotor is housed inside the casing. In the rotor blade cascade, a plurality of rotor blades are arranged in a circumferential direction of the turbine rotor. In the stationary blade cascade, a plurality of stationary blades are arranged in the circumferential direction of the turbine rotor between a diaphragm inner ring and a diaphragm outer ring. The spray unit sprays spray water to a space located upstream from a rotor blade cascade at a final stage among the rotor blade cascades at the plurality of stages inside the casing.

Abstract: A steam turbine 10 according to an embodiment includes rotor blades 22 implanted to a turbine rotor 21, stationary blades 26 making up a turbine stage together with the rotor blades 22, diaphragm outer rings 23 including an annular extending part 24 surrounding a periphery of the rotor blades 22, and supporting the stationary blades 26, and diaphragm inner rings 25 supporting the stationary blades 26. The steam turbine 10 further includes an annular slit 40 formed at an inner surface of the diaphragm outer ring 23 between the stationary blades 26 and the rotor blades 22 along a circumferential direction, and communication holes 50 provided in plural at an outer surface of the diaphragm outer ring 23 along the circumferential direction, communicated to the annular slit 40 from the outer surface side, and communicated to an exhaust chamber sucking water films via the annular slit 40.

Abstract: A turbine rotor assembly 10 comprises a turbine rotor and a plurality of moving blades 20 implanted in a circumferential direction of the rotor. A flow passage is formed between each of the moving blades 20 and a circumferentially adjacent moving blade 20. Each of the moving blades 20 comprises a suction side connecting member 22 protruded on a blade suction surface 21 and a pressure side connecting member 24 protruded on a blade pressure surface 23, wherein the suction side connecting member 22 of each of the moving blades 20 is configured to be connected with the pressure side connecting member 24 of the circumferentially adjacent moving blade 20 to form an intermediate connecting member 30 between the moving blade 20 and the circumferentially adjacent moving blade 20 during a rotation of the turbine rotor. A downstream side end edge 32 of the intermediate connecting member 30 is positioned at an upstream side of a throat S of the flow passage.

Abstract: In one embodiment, a calculation method of moisture loss in a steam turbine calculates first a wetness fraction at the inlet and outlet of each of stationary blade cascades and rotor blade cascades. Subsequently, the moisture loss is classified into (1) supersaturation loss, (2) condensation loss, (3) acceleration loss, (4) braking loss, (5) capture loss and (6) pumping loss, and a loss for calculation of the moisture loss is selected from the above losses (1) to (6) according to the wetness fraction of steam at the inlet and outlet of each blade cascade. An amount of each selected loss is calculated, and an amount of moisture loss at each blade cascade is calculated.

Abstract: A sealing device for a turbine has a sealing member provided in a gap between a rotor and a stator arranged to surround the rotor, and a fluid path provided within the stator, to introduce, into the stator, a cooling medium used to cool stationary blades extending radially inward from the stator, and to flow the cooling medium at least to an upstream side of the sealing member.

Abstract: In one embodiment, a sealing device includes seal fins provided on an inner circumferential surface of a stationary body or an outer circumferential surface of a rotating body so as to be adjacent to each other in an axial direction of the rotating body in a gap between the outer circumferential surface of the rotating body and the inner circumferential surface of the stationary body. The device further includes at least one opening member provided on the inner circumferential surface of the stationary body, the opening member being provided at a position between seal fins adjacent to each other in the axial direction, and having holes opened on a side of the inner circumferential surface of the stationary body.

Abstract: A steam turbine includes two or more rotating blades and a diaphragm outer ring. Each of the rotating blades includes a tip cover, moisture-trapping grooves, a droplet ejection hole, and a drain guide groove. The tip cover is provided to a tip of each of the rotating blades and is connected in contact with another tip cover adjacent to the tip cover. The moisture-trapping grooves are formed in a longitudinal direction of each of the rotating blades. The droplet ejection hole is to connect an outside of the tip cover on a side of the diaphragm outer ring with an inside of the tip cover. The drain guide groove is to connect ends of the moisture-trapping grooves on the side of the tip cover with the droplet ejection hole. The diaphragm outer ring includes a drain pocket which faces the droplet ejection hole.

Abstract: A steam turbine includes two or more rotating blades and a diaphragm outer ring. Each of the rotating blades includes a tip cover, moisture-trapping grooves, a droplet ejection hole, and a drain guide groove. The tip cover is provided to a tip of each of the rotating blades and is connected in contact with another tip cover adjacent to the tip cover. The moisture-trapping grooves are formed in a longitudinal direction of each of the rotating blades. The droplet ejection hole is to connect an outside of the tip cover on a side of the diaphragm outer ring with an inside of the tip cover. The drain guide groove is to connect ends of the moisture-trapping grooves on the side of the tip cover with the droplet ejection hole. The diaphragm outer ring includes a drain pocket which faces the droplet ejection hole.

Abstract: In one embodiment, a calculation method of moisture loss in a steam turbine calculates first a wetness fraction at the inlet and outlet of each of stationary blade cascades and rotor blade cascades. Subsequently, the moisture loss is classified into (1) supersaturation loss, (2) condensation loss, (3) acceleration loss, (4) braking loss, (5) capture loss and (6) pumping loss, and a loss for calculation of the moisture loss is selected from the above losses (1) to (6) according to the wetness fraction of steam at the inlet and outlet of each blade cascade. An amount of each selected loss is calculated, and an amount of moisture loss at each blade cascade is calculated.

Abstract: A steam turbine includes a bucket implanted in a turbine rotor and a nozzle disposed on an upstream side of the bucket and supported by a turbine casing, in which a plurality of stages, each including the bucket and the nozzle, are arranged axially in the turbine so as to define a steam path. A hydrophilic coating portion is disposed in the entire area or an area of at least one portion of a circumferential surface of the turbine rotor, surfaces of the nozzles, surfaces of the buckets, and an inner circumferential surface of the turbine casing.

Abstract: A row of moving blades for a steam turbine has moving blades elongated radially which are arranged peripherally around and secured to a turbine rotor. The row also has an intermediate support structure for holding the blades to each other at a radially intermediate position. The support structure has a shape of a streamline cross section. The support structure may include a tie wire secured to the blades, or lugs protruding from the blades and combined to each other. The support structure may include lugs protruding from the blades to each other, and a sleeve combining the lugs. The shape of a streamline cross section may have an obtuse-angle or acute-angle upstream part.

Abstract: A turbine rotor assembly 10 comprises a turbine rotor and a plurality of moving blades 20 implanted in a circumferential direction of the rotor. A flow passage is formed between each of the moving blades 20 and a circumferentially adjacent moving blade 20. Each of the moving blades 20 comprises a suction side connecting member 22 protruded on a blade suction surface 21 and a pressure side connecting member 24 protruded on a blade pressure surface 23, wherein the suction side connecting member 22 of each of the moving blades 20 is configured to be connected with the pressure side connecting member 24 of the circumferentially adjacent moving blade 20 to form an intermediate connecting member 30 between the moving blade 20 and the circumferentially adjacent moving blade 20 during a rotation of the turbine rotor. A downstream side end edge 32 of the intermediate connecting member 30 is positioned at an upstream side of a throat S of the flow passage.

Abstract: A row of moving blades for a steam turbine has moving blades elongated radially which are arranged peripherally around and secured to a turbine rotor 9. The row also has an intermediate support structure for holding the blades each other at a radially intermediate position. The support structure has a shape of streamline cross section. The support structure may include a tie wire secured to the blades, or lugs protruding from the blades and combined to each other. The support structure may include lugs protruding from the blades to each other, and a sleeve combining the lugs. The shape of streamline cross section may have an obtuse-angle or acute-angle upstream part.

Abstract: A steam turbine includes a bucket implanted in a turbine rotor and a nozzle disposed on an upstream side of the bucket and supported by a turbine casing, in which a plurality of stages, each including the bucket and the nozzle, are arranged axially in the turbine so as to define a steam path. A hydrophilic coating portion is disposed in the entire area or an area of at least one portion of a circumferential surface of the turbine rotor, surfaces of the nozzles, surfaces of the buckets, and an inner circumferential surface of the turbine casing.