Abstract: A steam turbine 10 of an embodiment includes a turbine rotor 30, rotor blade cascades 41 having rotor blades 40, stationary blade cascades 53 having stationary blades 52, and a steam passage 60 formed on a turbine stage, among turbine stages, including the rotor blades each having a blade height equal to or more than a blade height at which a loss generated when a leakage steam flown between a diaphragm inner ring 51 and the turbine rotor 30 jets into a main steam and a benefit brought by increasing the blade height of each of the rotor blades 40 in accordance with an increase in a flow rate of the main steam by an amount of the leakage steam are cancelled, and leading the leakage steam from an upstream side to a downstream side of a rotor disk 31.

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 axial-flow turbine according to an embodiment includes a plurality of nozzle structures and a plurality of blade structures. At least one nozzle structure includes an outer ring diaphragm and an inner ring diaphragm. The outer ring diaphragm and the inner ring diaphragm form an annular opening portion which extends in a circumferential direction therebetween. A nozzle is provided in a portion of a region of the annular opening portion in the circumferential direction, and a closing part is provided in another portion of the region of the annular opening portion in the circumferential direction. The closing part closes this other portion of the region to prevent a working fluid from flowing into this other portion of the region. A closing part medium passage is provided in the closing part and is configured to flow a cooling medium which cools the closing part.

Abstract: In one embodiment, a turbine using CO2 includes moving blades, stator blades, a working fluid transport flow path, a coolant transport flow path, and a coolant recovery flow path. The stator blades constitute turbine stages together with the moving blades. The working fluid transport flow path is configured to transport the working fluid sequentially to the turbine stages. The coolant transport flow path is configured to transport the coolant by allowing the coolant to sequentially pass through the inside of the stator blades from an upstream to a downstream of the working fluid. The coolant recovery flow path is configured to recover the coolant passing through the inside of the stator blade at a predetermined turbine stage and merge the recovered coolant with the working fluid transport flow path at a turbine stage on an upstream side of the predetermined turbine stage.

Abstract: A steam turbine 10 of an embodiment includes a turbine rotor 30, rotor blade cascades 41 having rotor blades 40, stationary blade cascades 53 having stationary blades 52, and a steam passage 60 formed on a turbine stage, among turbine stages, including the rotor blades each having a blade height equal to or more than a blade height at which a loss generated when a leakage steam flown between a diaphragm inner ring 51 and the turbine rotor 30 jets into a main steam and a benefit brought by increasing the blade height of each of the rotor blades 40 in accordance with an increase in a flow rate of the main steam by an amount of the leakage steam are cancelled, and leading the leakage steam from an upstream side to a downstream side of a rotor disk 31.

Abstract: An axial-flow turbine according to an embodiment includes a plurality of nozzle structures and a plurality of blade structures. At least one nozzle structure includes an outer ring diaphragm and an inner ring diaphragm. The outer ring diaphragm and the inner ring diaphragm form an annular opening portion which extends in a circumferential direction therebetween. A nozzle is provided in a portion of a region of the annular opening portion in the circumferential direction, and a closing part is provided in another portion of the region of the annular opening portion in the circumferential direction. The closing part closes this other portion of the region to prevent a working fluid from flowing into this other portion of the region. A closing part medium passage is provided in the closing part and is configured to flow a cooling medium which cools the closing part.

Abstract: An axial-flow turbine has turbine nozzles, a heat shield plate, a first communication hole formed in the turbine rotor and connected to the space, to flow a cooling medium, a first opening formed in at least any one of the two adjacent rotor disks, to be connected to the space, a second communication hole connected to the space through the first opening, to communicate with an implant unit of the turbine rotor blade in the rotor disk, a third communication hole connected to the second communication hole, to communicate along an effective length of the turbine rotor blade, a second opening formed in a side face of the turbine rotor blade, to be connected to the third communication hole, and a third opening formed in an outer circumferential end face of the turbine rotor blade, to be connected to the third communication hole.

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: In one embodiment, a turbine using CO2 includes moving blades, stator blades, a working fluid transport flow path, a coolant transport flow path, and a coolant recovery flow path. The stator blades constitute turbine stages together with the moving blades. The working fluid transport flow path is configured to transport the working fluid sequentially to the turbine stages. The coolant transport flow path is configured to transport the coolant by allowing the coolant to sequentially pass through the inside of the stator blades from an upstream to a downstream of the working fluid. The coolant recovery flow path is configured to recover the coolant passing through the inside of the stator blade at a predetermined turbine stage and merge the recovered coolant with the working fluid transport flow path at a turbine stage on an upstream side of the predetermined turbine stage.

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: An axial-flow turbine has turbine nozzles, a heat shield plate, a first communication hole formed in the turbine rotor and connected to the space, to flow a cooling medium, a first opening formed in at least any one of the two adjacent rotor disks, to be connected to the space, a second communication hole connected to the space through the first opening, to communicate with an implant unit of the turbine rotor blade in the rotor disk, a third communication hole connected to the second communication hole, to communicate along an effective length of the turbine rotor blade, a second opening formed in a side face of the turbine rotor blade, to be connected to the third communication hole, and a third opening formed in an outer circumferential end face of the turbine rotor blade, to be connected to the third communication hole.

Abstract: An axial flow turbine stage structure has: an annular diaphragm inner ring; an annular diaphragm outer ring arranged radially outside and coaxially with the diaphragm inner ring and separated from the diaphragm inner ring by an annular flow path interposed between them; stationary blades arranged peripherally at intervals in the annular flow path and rigidly secured to the diaphragm inner ring and the diaphragm outer ring; and moving blades rigidly secured to the outer periphery of a rotatable rotor and arranged peripherally at intervals respectively at axially downstream sides of the stationary blades. Through holes are formed in the diaphragm outer ring so as to allow axial upstream side and axially downstream side of the stationary blades to communicate with each other.

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 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: An axial flow turbine provided with a stage composed of a turbine nozzle and a turbine rotor blade arranged in an axial flow direction. Both end portions of a nozzle blade of the turbine nozzle are supported by a diaphragm inner ring and a diaphragm outer ring, and a flow passage is formed to have its diameter expanded from an upstream stage to a downstream stage. In such axial flow turbine, trailing edges at ends of the nozzle blade supported by the diaphragm inner ring and the diaphragm outer ring are curved as a curvature to an outlet side, and an intermediate portion between the trailing edges is formed to be straight.

Abstract: An axial flow turbine stage structure has: an annular diaphragm inner ring; an annular diaphragm outer ring arranged radially outside and coaxially with the diaphragm inner ring and separated from the diaphragm inner ring by an annular flow path interposed between them; stationary blades arranged peripherally at intervals in the annular flow path and rigidly secured to the diaphragm inner ring and the diaphragm outer ring; and moving blades rigidly secured to the outer periphery of a rotatable rotor and arranged peripherally at intervals respectively at axially downstream sides of the stationary blades. Through holes are formed in the diaphragm outer ring so as to allow axial upstream side and axially downstream side of the stationary blades to communicate with each other.

Abstract: An axial flow turbine provided with a stage composed of a turbine nozzle and a turbine rotor blade arranged in an axial flow direction. Both end portions of a nozzle blade of the turbine nozzle are supported by a diaphragm inner ring and a diaphragm outer ring, and a flow passage is formed to have its diameter expanded from an upstream stage to a downstream stage. In such axial flow turbine, trailing edges at ends of the nozzle blade supported by the diaphragm inner ring and the diaphragm outer ring are curved as a curvature to an outlet side, and an intermediate portion between the trailing edges is formed to be straight.

Abstract: An axial flow turbine provided with a stage composed of a turbine nozzle and a turbine rotor blade arranged in an axial flow direction. Both end portions of a nozzle blade of the turbine nozzle are supported by a diaphragm inner ring and a diaphragm outer ring, and a flow passage is formed to have its diameter expanded from an upstream stage to a downstream stage. In such axial flow turbine, trailing edges at ends of the nozzle blade supported by the diaphragm inner ring and the diaphragm outer ring are curved as a curvature to an outlet side, and an intermediate portion between the trailing edges is formed to be straight.