STATOR BLADE AND GAS TURBINE THAT INCLUDES THE SAME

Abstract

Stator blade (50) provided in a gas turbine (10), comprising: a blade body (51) having a blade shape in cross-section and extending in a blade height direction (Dh) having a directional component perpendicular to the cross-section; a first insert (90) and a second insert (95) having a tubular shape, extending in a tube height direction and arranged within the blade body (51) such that the tube height direction faces the blade height direction (Dh); and an end cover (100), wherein the blade body (51) includes several blade air channels (80) extending in the blade height direction (Dh) within the blade body (51), of which several blade air channels a first blade air channel (81) and a second blade air channel (85) each have a first blade height side (Dh1) and a second blade height side (Dh2),wherein one end is open at the first blade height side (Dh1) of the first blade air channel (81), and one end is open at the second blade height side (Dh2) of the second blade air channel (85), each of the first insert (90) and the second insert (95) comprising: an outer circumferential plate section (91, 96) having a tubular shape and extending in the tube height direction, and a sealing plate section (93, 98) closing one end on a tube height sealing side which is a side of the outer circumferential plate section from two sides in the tube height direction, the outer circumferential plate section (91) of the first insert (90) is closed at the second blade height side (Dh2) by the sealing plate section (93), the outer circumferential plate section (96) of the second insert (95) is closed at the first blade height side (Dh1) by the The sealing plate section (98) is closed, the outer perimeter plate section has several impact holes (92),which penetrate from an inside to an outside of the tubular outer circumferential plate section, the outer circumferential plate section (91) of the first insert (90) has a gap that is present between the outer circumferential plate section (91) of the first insert (90) and a first channel-defining surface of the blade body, which defines the first blade air channel (81), and is arranged within the first blade air channel (81), such that cooling air (Ac) flows from an opening (90o) of the first insert (90) into the outer circumferential plate section (91), the outer circumferential plate section (96) of the second insert (95) is configured such that the tube-height opening side of the second insert (95) faces the second blade height side (Dh2), a gap that is present between the outer circumferential plate section (96) of the second insert (95) and a second channel-defining surface of the blade body (51) is present,which defines the second blade air channel (85), has and is arranged within the second blade air channel (85) such that cooling air (Ac) flows from an opening (95o) of the second insert (95), and the end cover is provided on the second blade height side (Dh2) of the blade body (51) such that the cooling air (Ac) which is expelled from the multiple impact holes (92) of the first insert (90) between the outer circumferential plate section (91) of the first insert (90) and the first channel-defining surface (81p) is directed from the opening (95o) of the second insert (95) through the opening (90o) of the first blade air channel (81) into the second insert (95), and covers the opening of the first blade air channel (81) and the opening (95o) of the second insert (95).

Description

Technical field

[0001] The present invention relates to a stator blade and a gas turbine comprising the same.

[0002] Priority is claimed by Japanese patent application No. 2021-053113, filed on March 26, 2021, the contents of which are incorporated herein by reference. State of the art

[0003] A gas turbine contains a compressor that compresses air to produce compressed air, a combustion chamber that burns a fuel in the compressed air to produce a fuel gas, and a turbine driven by the combustion gas. The turbine includes a turbine rotor that rotates around an axis; a turbine casing that covers the rotor; and several rows of stator blades. The turbine rotor includes a rotor shaft around the axis and several rows of rotor blades attached to the rotor shaft. The multiple rows of rotor blades are aligned in an axial direction along the axis. Each of the rotor blade rows contains several rotor blades aligned circumferentially with respect to the axis. The multiple rows of stator blades are aligned axially and are attached to an inner circumferential side of the turbine casing.Each of the multiple stator blade rows is arranged on an axial upstream side of any one of the multiple rotor blade rows. Each stator blade row contains multiple stator blades aligned circumferentially with respect to the axis.

[0004] The stator blade comprises a blade body, which forms a blade shape by extending radially with respect to the axis, an inner shroud provided on the radial inside of the blade body, and an outer shroud provided on the radial outside of the blade body. The blade body of the stator blade is located within a combustion gas channel through which the combustion gas flows. The inner shroud defines a radial inside edge of the combustion gas channel. The outer shroud defines a radial outside edge of the combustion gas channel.

[0005] The stator blade of the gas turbine is exposed to a high-temperature combustion gas. Therefore, the stator blade is generally cooled by air or similar means.

[0006] For example, the blade body of the stator blade disclosed below in PTL 1 incorporates several cooling air channels through which cooling air passes. Each of these cooling air channels extends in a blade height direction Dh, which is the radial direction with respect to the axis. The stator blade includes a baffle plate located within one of these cooling air channels. The baffle plate is positioned within a cooling air channel such that it extends within that channel in the blade height direction Dh, dividing the interior of that channel into a blade surface side of the blade body and an interior side opposite that surface. Several baffle holes are formed in the baffle plate.

[0007] In the stator blade, within a single cooling channel, the cooling air, which flows inwards with the baffle plate as a reference, is expelled from the multiple baffle holes of the baffle plate towards the blade surface. The cooling air expelled from the multiple baffle holes collides at a channel-defining surface with a section that has a back-to-back relationship with the blade surface defining the single cooling air channel, and thus performs impact cooling on that section. List of citations from patent literature

[0008] [PTL 1] Japanese Patent No. 4885275 Summary of Invention Technical problem

[0009] With regard to the stator blade of the gas turbine, it is desirable to cool the stator blade and reduce the amount of air consumed for cooling the stator blade as much as possible, while improving the durability of the stator blade.

[0010] Therefore, one objective of the present disclosure is to provide a stator blade capable of being efficiently cooled and a gas turbine comprising the stator blade. Solution to the problem

[0011] According to one aspect of the invention, a stator blade provided in a gas turbine is supplied to achieve the above-described objective.

[0012] The stator blade comprises a blade body, which has a blade shape in cross-section and extends in a blade height direction having a directional component perpendicular to the cross-section; a first insert and a second insert, which have a tubular shape, extend in a tube height direction, and are arranged within the blade body such that the tube height direction faces the blade height direction; and an end cover. The blade body contains several blade air channels extending in the blade height direction within the blade body. Of the several blade air channels, both a first blade air channel and a second blade air channel have an open end on a blade height side, which is one side of a first blade height side and a second blade height side in the blade height direction.Both the first and second inserts feature an outer circumferential plate section, which has a tubular shape and extends vertically along the pipe, and a sealing plate section that closes one end on a vertical sealing side, which is one side of the outer circumferential plate section in the pipe's vertical direction. The outer circumferential plate section has several impact holes that penetrate from an inner to an outer side of the tubular outer circumferential plate section. A vertical opening side, which is the other side of the outer circumferential plate section in the pipe's vertical direction, is open.The outer circumferential plate section of the first insert has a gap between the outer circumferential plate section of the first insert and a first channel-defining surface of the blade body, which defines the first blade air channel, and is positioned within the first blade air channel so that cooling air flows from an opening of the first insert into the outer circumferential plate section. The outer circumferential plate section of the second insert is configured such that the tube-height opening side of the second insert faces one blade height side, has a gap between the outer circumferential plate section of the second insert and a second channel-defining surface of the blade body, which defines the second blade air channel, and is positioned within the second blade air channel so that cooling air flows from an opening of the second insert.The end cover is provided on one blade height side of the blade body, so that the cooling air, which is expelled from the multiple impact holes of the first insert between the outer circumferential plate section of the first insert and the first channel-defining surface, is directed from the opening of the second insert through the opening of the first blade air channel into the second insert, and covers the opening of the first blade air channel and the opening of the second insert.

[0013] In this scenario, the cooling air flowing into the first insert, located within the first blade air channel, performs impingement cooling on the first channel-defining surface. Furthermore, at least a portion of the cooling air flows into the second insert, located within the second blade air channel. The cooling air flowing into the second insert also performs impingement cooling on the second channel-defining surface. Therefore, in this scenario, the stator blade can be cooled more efficiently, and the amount of cooling air consumed can be reduced, compared to expelling the cooling air Ac flowing into an insert to a combustion gas channel immediately after it has performed impingement cooling on the inside of the blade body.

[0014] According to another aspect of the invention, a gas turbine is provided to achieve the above-described objective.

[0015] The gas turbine contains a stator blade of the type described above, a rotor that rotates around an axis, and a casing that covers one outer circumferential surface of the rotor. The stator blade is attached to an inner circumferential surface of the casing. Advantageous effects of the invention

[0016] According to one aspect of the present disclosure, a stator blade can be effectively cooled, and the amount of cooling air consumed can be minimized while improving durability. Brief description of the drawings Fig. Figure 1 is a schematic sectional view of a gas turbine according to an embodiment of the present disclosure. Fig. Figure 2 is a sectional view showing a major part of the gas turbine according to the embodiment of the present disclosure. Fig. Figure 3 is a perspective view of a stator blade according to the first embodiment of the present disclosure. Fig. Figure 4 is a sectional view of the stator blade in a plane containing a curvature line according to the first embodiment of the present disclosure. Fig. 5 is a section view along line VV in Fig. 4. Fig. Figure 6 is a perspective view of an insert according to the first embodiment of the present disclosure. Fig. Figure 7 is a sectional view of a stator blade in a plane perpendicular to an axis according to a second embodiment of the present disclosure. Fig. 8 is a sectional view along line VIII-VIII in Fig. 7. Fig. Figure 9 is a sectional view of a stator blade in a plane containing a curvature line according to a first modification example of the first embodiment of the present disclosure. Fig. Figure 10 is a sectional view of a stator blade in a plane containing a curvature line according to a second modification example of the first embodiment of the present disclosure. Fig. Figure 11 is a sectional view of a stator blade in a plane containing a curvature line according to a third modification example of the first embodiment of the present disclosure. Description of embodiments

[0017] Various embodiments of the present invention and examples of modifications thereof are described in detail below with reference to the drawings. [Design of gas turbine]

[0018] One embodiment of a gas turbine is described with reference to Fig. 1 and Fig. 2 described.

[0019] As in Fig. Figure 1 shows a gas turbine 10 of the present embodiment comprising a compressor 20 which compresses air A; a combustion chamber 30 which burns a fuel F in the air A compressed by the compressor 20 to produce a combustion gas G; and a turbine 40 which is driven by the combustion gas G.

[0020] The compressor 20 comprises a compressor rotor 21 rotating about an axis Ar; a compressor housing 25 covering the compressor rotor 21; and several stator blade rows 26. The turbine 40 comprises a turbine rotor 41 rotating about the axis Ar; a turbine housing 45 covering the turbine rotor 41; and several stator blade rows 46. Hereinafter, a direction extending from the axis Ar is referred to as an axial direction Da, a circumferential direction about the axis Ar is simply referred to as a circumferential direction Dc, and a direction perpendicular to the axis Ar is referred to as a radial direction Dr. Furthermore, a side in the axial direction Da is referred to as an axial upstream side Dau, and a side opposite this is referred to as an axial downstream side Dad.Furthermore, a side that is closer to the axis Ar in the radial direction Dr is called a radial inside Dri, and a side opposite this is called a radial outside Dro.

[0021] The compressor 20 is arranged on the axial upstream side Dau with respect to the turbine 40.

[0022] The compressor rotor 21 and the turbine rotor 41 are located on the same axis Ar and are connected to form a gas turbine rotor 11. For example, a rotor of a generator GEN is connected to the gas turbine rotor 11. The gas turbine 10 further includes an intermediate casing 16. The intermediate casing 16 is arranged between the compressor casing 25 and the turbine casing 45 in the axial direction Da. The compressor casing 25, the intermediate casing 16, and the turbine casing 45 are connected to form a gas turbine casing 15.

[0023] The compressor rotor 21 comprises a rotor shaft 22 extending in the axial direction Da around the axis Ar and several rotor blade rows 23 attached to the rotor shaft 22. The multiple rotor blade rows 23 are aligned in the axial direction Da. Each rotor blade row 23 is formed from several rotor blades 23a aligned in the circumferential direction Dc. A stator blade row 26 of the multiple stator blade rows 26 is arranged on the axial downstream side Dad of each of the multiple rotor blade rows 23. Each of the stator blade rows 26 is provided within the compressor housing 25. Each of the stator blade rows 26 is formed from several stator blades 26a arranged in the circumferential direction Dc.

[0024] As in Fig. 1 and Fig. As shown in Figure 2, the turbine rotor 41 includes a rotor shaft 42 extending axially around the axis Ar in the direction Da, and several rows of rotor blades 43 attached to the rotor shaft 42. The multiple rows of rotor blades 43 are aligned axially in the direction Da. Each of the rotor blade rows 43 is formed from multiple rotor blades 43a aligned circumferentially in the direction Dc. A row of stator blades 46 from the multiple rows of stator blades 46 is arranged on the axial upstream side Dad of each of the multiple rows of rotor blades 43. Each of the stator blade rows 46 is provided within the turbine casing 45. Each of the stator blade rows 46 is formed from multiple stator blades 46a arranged circumferentially in the direction Dc.

[0025] The turbine casing 45 comprises a tubular outer casing 45a, forming its outer shell, an inner casing 45b, which is attached to the inside of the outer casing 45a, and several ring segments 45c, which are attached to the inside of the inner casing 45b. Each of the several ring segments 45c is positioned between the several stator blade rows 46. Therefore, the rotor blade row 43 is arranged on the radial inner side Dri of each of the ring segments 45c.

[0026] An annular space formed between an outer circumferential side of the rotor shaft 42 and an inner circumferential side of the turbine housing 45, in which the stator blade 46a and the rotor blade 43a are arranged in the axial direction Da, forms a combustion gas channel 49 through which the combustion gas G flows from the combustion chambers 30.

[0027] The combustion chamber 30 is attached to the intermediate housing 16.

[0028] As in Fig. As shown in Figure 1, the compressor 20 compresses the air A to produce compressed air. The compressed air flows into the combustion chamber 30. The fuel F is supplied to the combustion chamber 30. Inside the combustion chamber 30, the fuel F is burned in the compressed air to produce the high-temperature and high-pressure combustion gas G. The combustion gas G is fed from the combustion chamber 30 to the combustion gas channel 49 within the turbine 40. The combustion gas G rotates the turbine rotor 41 as it flows through the combustion gas channel 49 towards the axial downstream side Dad. A rotor of the generator GEN, connected to the gas turbine rotor 11, is rotated by the rotation of the turbine rotor 41. As a result, the generator GEN produces electricity.

[0029] Below are described various embodiments relating to the stator blade that forms a first-stage stator blade row 46. [First embodiment of stator blade]

[0030] A first embodiment of the stator blade according to the present invention is described with reference to Fig. 3 to Fig. 6 described.

[0031] As in Fig. As shown in Figure 3, a stator blade 50 of the present embodiment comprises a blade body 51, an inner casing 60i, and an outer casing 60o. A cross-sectional area of ​​the blade body 51 has a blade shape, and the blade body 51 extends in a blade height direction Dh, which has a directional component perpendicular to the cross-section. The inner casing 60i is provided at one end on one side in the blade height direction Dh within the blade body 51. The outer casing 60i is provided at one end on the other side in the blade height direction Dh within the blade body 51. The blade body 51, the inner casing 60i, and the outer casing 60o are integrally formed by casting or the like.

[0032] The blade height direction is the radial direction Dr in a state in which the stator blade 50 is attached to the turbine casing 45 (see Fig. 2) Furthermore, a first blade height side Dh1 on one side in the blade height direction Dh is the radial inner side Dri, and a second blade height side Dh2 on the other side in the blade height direction Dh is the radial outer side Dro. Therefore, the inner casing 60i is provided on the radial inner side Dri of the blade body 51, and the outer casing 60o is provided on the radial outer side Dro of the blade body 51. Therefore, in the present embodiment, in some cases, the blade height direction Dh can be referred to as the radial direction Dr, the first blade height side Dh1 can be referred to as the radial inner side Dri, and the second blade height side Dh2 can be referred to as the radial outer side Dro.

[0033] As in Fig. 3 to Fig. Figure 5 shows a blade surface, which is an outer surface of the blade body 51, a leading edge 52, a trailing edge 53, a suction surface 54, which is a convex surface, and a pressure surface 55, which is a concave surface. The leading edge 52 and the trailing edge 53 are located in a connecting section between the suction surface 54 and the pressure surface 55. The leading edge 52, the trailing edge 53, the suction surface 54, and the pressure surface 55 all extend in the radial direction Dr, which is the blade height direction Dh. The leading edge 52 is located on the axial upstream side Dau with respect to the trailing edge 53 in a state in which the stator blade 50 is attached to the turbine casing 45.Furthermore, in a state in which the stator blade 50 is attached to the turbine housing 45, the suction surface 54 faces a circumferential suction side Den, which is one side in the circumferential direction Dc, and the pressure surface 55 faces a circumferential pressure side Dcp, which is the other side in the circumferential direction Dc.

[0034] The blade body 51 is arranged within the combustion gas channel 49, through which the combustion gas G passes. The blade body 51 contains several blade air channels 80 that extend radially Dr within the blade body 51. The inner sheath 60i defines an edge on the radial inner side Dri of the annular combustion gas channel 49. Furthermore, the outer sheath 60o defines an edge on the radial outer side Dro of the annular combustion gas channel 49.

[0035] The inner casing 60i contains a casing body 61, a circumferential wall 71 and a holder 76.

[0036] The casing body 61 is a plate-shaped element extending in a direction that includes a directional component perpendicular to the radial direction Dr, which is the blade height direction Dh. The casing body 61 comprises a gas path surface 64, a counter-gas path surface 65, a front end surface 62f, a rear end surface 62b, a suction end surface 63n, and a pressure end surface 63p.

[0037] The gas path surface 64 is a surface facing the radial outer side Dro, which is the second blade height side Dh2 with which the combustion gas G comes into contact. The counter-gas path surface 65 is a surface facing the radial inner side Dri, which is the first blade height side Dh1. The counter-gas path surface 65 has a back-to-back relationship with the gas path surface 64. The leading end surface 62f is a surface located closer to the axial upstream side Dau than the blade body 51 and faces the axial upstream side Dau. The trailing end surface 62b is a surface located closer to the axial downstream side Dad than the blade body 51 and faces the axial downstream side Dad. The suction-side end surface 63n is a surface that is located closer to the circumferential suction side Den than the blade body 51 in the casing body 61 and faces the circumferential suction side Den.The suction-side end surface 63n connects the front end surface 62f and the rear end surface 62b. The pressure-side end surface 63p is a surface located closer to the circumferential pressure side Dcp than the blade body 51 within the casing body 61 and faces the circumferential pressure side Dcp. The pressure-side end surface 63p connects the front end surface 62f and the rear end surface 62b. The rear end surface 62b is located at a distance from the front end surface 62f to the axial downstream side and is substantially parallel to the front end surface 62f. Furthermore, the pressure-side end surface 63p is located at a distance from the suction-side end surface 63n to a side in the circumferential direction Dc and is substantially parallel to the suction-side end surface 63n. Therefore, when viewed in the radial direction Dr, the casing body 61 has a parallelogram shape.

[0038] The circumferential wall 71 is a wall that projects from the casing body 61 to the radial inner side Dri along an outer circumferential edge of the casing body 61. The circumferential wall 71 comprises a front circumferential wall 71f and a rear circumferential wall 71b, which face each other in the axial direction Da, and a pressure-side circumferential wall 71p and a suction-side circumferential wall 71n, which face each other in the circumferential direction Dc. The front circumferential wall 71f is located closer to the axial upstream side Dau than the blade body 51. A surface of the front circumferential wall 71f, which faces the axial upstream side Dau, forms a section of the front end surface 62f of the inner casing 60i. The rear circumferential wall 71b is located closer to the axial downstream side Dad than the blade body 51. The pressure-side circumferential wall 71p is located closer to the circumferential pressure side Dcp than the blade body 51.A surface of the pressure-side circumferential wall 71p, facing the circumferential pressure side Dcp, forms a section of the pressure-side end surface 63p of the inner casing 60i. The suction-side circumferential wall 71n is located closer to the circumferential suction side Den than the blade body 51. A surface of the suction-side circumferential wall 71n, facing the circumferential suction side Den, forms a section of the suction-side end surface 63n of the inner casing 60i.

[0039] In the inner casing 60i, a cavity 72 recessed towards the radial inner side Dri is formed by the casing body 61 and the circumferential wall 71. The cavity 72 is defined by the counter-gas path surface 65 of the casing body 61, a surface of the front circumferential wall 71f facing the axial downstream side Dad, a surface of the rear circumferential wall 71b facing the axial upstream side Dau, a surface of the pressure-side circumferential wall 71p facing the circumferential suction side Den, and a surface of the suction-side circumferential wall 71n facing the circumferential pressure side Dcp.

[0040] The holder 76 is located between the front circumferential wall 71f and the rear circumferential wall 71b in the axial direction Da and extends from the suction-side end surface 63n to the pressure-side end surface 63p. The holder 76 is connected at one end 17a (see Fig. 2 and Fig. 4) on the radial outer side Dro of an inner cover 17 attached to the gas turbine casing 15 and serves to support a section on the radial inner side Dri of the stator blade 50 on the inner cover 17.

[0041] The outer casing 60o has essentially the same configuration as the inner casing 60i. Like the inner casing 60i, the outer casing 60o therefore also contains the casing body 61 and the circumferential wall 71. However, the outer casing 60o does not have a section corresponding to the holder 76 of the inner casing 60i. As with the casing body 61 of the inner casing 60i, the casing body 61 of the outer casing 60o also contains the gas path surface 64, the counter-gas path surface 65, the front end surface 62f, the rear end surface 62b, the suction end surface 63n, and the pressure end surface 63p. Furthermore, as with the circumferential wall 71 of the inner casing 60i, the circumferential wall 71 of the outer casing 60o also contains the front circumferential wall 71f, the rear circumferential wall 71b, the pressure-side circumferential wall 71p and the suction-side circumferential wall 71n.The front circumferential wall 71f and the rear circumferential wall 71b of the outer casing 60o serve to attach the stator blade 50 to an inner circumferential side of the turbine casing 45 (see . Fig. 2).

[0042] As in Fig. 3 and Fig. As shown in Figure 5, the multiple blade air channels 80 formed within the blade body 51 are aligned along a camber line CL of the blade body 51. Of the multiple blade air channels 80, the one closest to the axial upstream side Dau is designated as a leading blade air channel 80f, and the one closest to the axial downstream side Dad is designated as a trailing blade air channel 80b. Furthermore, two blade air channels 80 located between the leading blade air channel 80f and the trailing blade air channel 80b are designated as interblade air channels 80m.Furthermore, of the two inter-blade air channels 80m, the inter-blade air channel 80m on the axial upstream side Dau is designated as a first blade air channel 81, and the inter-blade air channel 80m on the axial downstream side Dad is designated as a second blade air channel 85.

[0043] In the leading edge air channel 80f, one end on the radial inner side Dri, which is the first blade height side Dh1, is closed, and one end on the radial outer side Dro, which is the second blade height side Dh2, is open. Several leading edge exhaust holes 80fa, which extend from the leading edge air channel 80f to the combustion gas channel 49, are formed on a leading edge section that includes the leading edge 52 of the blade body 51. One end on the radial inner side Dri of the blade body 51 forms a section of the counter-gas path surface 65 of the inner shroud 60i, and one end on the radial outer side Dro of the blade body 51 forms a section of the counter-gas path surface 65 of the outer shroud 60o. Therefore, an opening 80fo of the front blade air channel 80f is open at the counter-gas path surface 65 of the outer casing 60o.

[0044] In the rear blade air channel 80b, one end on the radial inner side Dri, which is the first blade height side Dh1, is closed, and one end on the radial outer side Dro, which is the second blade height side Dh2, is open. An opening 80bo of the rear blade air channel 80b is open at the counter-gas path surface 65 of the outer casing 60o. Several rear exhaust holes 80ba, which extend from the rear blade air channel 80b to the combustion gas channel 49, are formed in a rear section that includes the trailing edge 53 of the blade body 51.

[0045] In the first blade air channel 81, one end on the radial inner side Dri, which is the first blade height side Dh1, and one end on the radial outer side Dro, which is the second blade height side Dh2, are open. A first opening 82f, which is an opening on the first blade height side Dh1 of the first blade air channel 81, is open at the counter-gas path surface 65 of the inner casing 60i. Furthermore, a second opening 82s, which is an opening on the second blade height side Dh2 of the first blade air channel 81, is open at the counter-gas path surface 65 of the outer casing 60o. The blade body 51 has several pressure-side first ejection holes 83pf that extend from a first channel-defining surface 81p, which defines the first blade air channel 81 of the blade body 51, to a pressure-side first blade surface section 55f, which is a section of the pressure surface 55.The pressure-side first blade surface section 55f is a section that has a back-to-back relationship with the first blade air channel 81 on the pressure surface 55 of the blade body 51. Furthermore, the blade body 51 has several suction-side first ejection holes 83nf that extend from the first channel-defining surface 81p, which defines the first blade air channel 81 of the blade body 51, to a suction-side first blade surface section 54f, which is a section of the suction surface 54. The suction-side first blade surface section 54f is a section that has a back-to-back relationship with the first blade air channel 81 on the suction surface 54 of the blade body 51.

[0046] In the second blade air channel 85, one end on the radial inner side Dri, which is the first blade height side Dh1, is closed, and one end on the radial outer side Dro, which is the second blade height side Dh2, is open. An opening 86 of the second blade air channel 85 is open at the counter-gas path surface 65 of the outer casing 60°. The blade body 51 has several pressure-side second exhaust holes 87ps that extend from a second channel-defining surface 85p, which defines the second blade air channel 85 of the blade body 51, to a pressure-side second blade surface section 55s, which is a section of the pressure surface 55.

[0047] The pressure-side second blade surface section 55s is a section that has a back-to-back relationship with the second blade air channel 85 on the pressure surface 55 of the blade body 51. Furthermore, the blade body 51 has several suction-side second exhaust holes 87ns that extend from the second channel-defining surface 85p, which defines the second blade air channel 85 of the blade body 51, to a suction-side second blade surface section 54s, which is a section of the suction surface 54. The suction-side second blade surface section 54s is a section that has a back-to-back relationship with the second blade air channel 85 on the suction surface 54 of the blade body 51.

[0048] As described above, both the first blade air channel 81 and the second blade air channel 85 have an open end on the radial outer side Dro, which is the second blade height side Dh2.

[0049] As in Fig. 3 to Fig. As shown in Figure 6, the stator blade of the present embodiment further comprises a first insert 90, a second insert 95, an end cover 100, several first guide elements 110 and a second guide element 115.

[0050] The first insert 90 is arranged within the first blade air channel 81, and the second insert 95 is arranged within the second blade air channel 85. As shown in Fig. As shown in Figure 6, the first insert 90 comprises an outer circumferential plate section 91, a sealing plate section 93, and a flange section 94. Furthermore, the second insert 95 comprises an outer circumferential plate section 96, a sealing plate section 98, and a flange section 99. The outer circumferential plate sections 91 and 96 of the first insert 90 and the second insert 95 are tubular in shape and extend in a pipe height direction Dih. From two sides in the pipe height direction Dih, one side is designated as a pipe height sealing side Dih1, and the other side is designated as a pipe height opening side Dih2. The sealing plate sections 93 and 98 close the ends of the outer circumferential plate sections 91 and 96 on the pipe height sealing side Dih1. The sealing plate section is not provided at the end sections of the outer circumferential plate sections 91 and 96 on the pipe height opening side Dih2.Therefore, at the end sections of the outer circumferential plate sections 91 and 96 on the pipe height opening side Dih2, insert openings 90° and 95° are formed for introducing cooling air into the outer circumferential plate sections 91 and 96. The flange sections 94 and 99 extend from the ends on the pipe height opening side Dih2 along all outer circumferential surfaces of the outer circumferential plate sections 91 and 96 towards the outer circumferential side.

[0051] The outer circumferential plate section 91 of the first insert 90 is arranged within the first blade air channel 81 such that the pipe height opening side Dih2 faces the first blade height side Dh1, and a gap exists between the outer circumferential plate section 91 and the first channel-defining surface 81p of the blade body 51, which defines the first blade air channel 81. The flange section 94 is connected to an edge of the first opening 82f of the first blade air channel 81 to close the gap between the outer circumferential plate section 91 and the first channel-defining surface 81p. The gap between the outer circumferential side of the outer circumferential plate section 91 of the first insert 90 and the first channel-defining surface 81p forms a first blade-internal cavity C1 into which the cooling air Ac flows.

[0052] In the outer circumferential plate section 91 of the first insert 90, a section facing the pressure-side first blade surface section 55f and a section facing the suction-side first blade surface section 54f have several impact holes 92 penetrating from the inside to the outside of the outer circumferential plate section 91.

[0053] The outer circumferential plate section 96 of the second insert 95 is arranged within the second blade air channel 85 such that the pipe height opening side Dih2 faces the second blade height side Dh2, and a gap exists between the outer circumferential plate section 96 and the second channel-defining surface 85p of the blade body 51, which defines the second blade air channel 85. The flange section 99 is connected to an edge of the opening 86 of the second blade air channel 85 to close the gap between the outer circumferential plate section 96 and the second channel-defining surface 85p. The gap between the outer circumferential side of the outer circumferential plate section 96 of the second insert 95 and the second channel-defining surface 85p forms a second blade-internal cavity C2 into which the cooling air Ac flows.

[0054] Of the outer circumferential plate section 96 of the second insert 95, a section facing the pressure-side second blade surface section 55s and a section facing the suction-side second blade surface section 54s have several impact holes 97 penetrating from the inside to the outside of the outer circumferential plate section 96.

[0055] The second blade surface sections 54s and 55s on the blade surface are located closer to the axial downstream side Dad than the first blade surface sections 54f and 55f. Therefore, the positions of the second blade surface sections 54s and 55s are positions where, while the gas turbine 10 is driven, the pressure of the sections along the second blade surface sections 54s and 55s outside the blade body 51 is lower than the pressure of the sections along the first blade surface sections 54f and 55f outside the blade body 51.

[0056] The end cover 100 comprises a cover plate section 101 and an outer circumferential plate section 102. The outer circumferential plate section 102 extends along an edge of the cover plate section 101 in a direction substantially perpendicular to the cover plate section 101. The end cover 100 is located on the second blade height side Dh2 of the blade body 51. The cover plate section 101 faces a region in which the first blade air channel 81 and the second air channel are located on the counter-gas path surface 65 of the outer shroud 60° at a distance in the blade height direction Dh. The outer circumferential plate section 102 of the end cover 100 is connected to an edge of a region in which the first blade air channel 81 and the second air channel are located on the counter-gas path surface 65 of the outer shroud 60°.Therefore, the end cover 100 can direct the cooling air Ac, which flows from the second opening 82s of the first blade air channel 81 into the second blade air channel 85, from the opening 86 of the second blade air channel 85.

[0057] As in Fig. As shown in Figure 6, each of the multiple first guide elements 110 includes a first groove element 111 having a first groove 112 extending in the pipe height direction Dih, and a first convex element 113 entering the inside of the first groove 112 and being relatively movable in the pipe height direction Dih with respect to the first groove 112. The multiple first groove elements 111 are attached to the first channel-defining surface 81p at a distance along the circumference of the first channel-defining surface 81p (see Figure 6). Fig. 4 and Fig. 5) Each of the multiple first convex elements 113 is arranged such that it enters any one first groove 112 of the multiple first groove elements 111 and is attached to the outer circumferential plate section 91 of the first insert 90. Therefore, the first guide element 110 allows displacement of the first insert 90 in the pipe height direction Dih and controls displacement of the first insert 90 in a direction perpendicular to the pipe height direction Dih.

[0058] As in Fig. As shown in Figure 6, the second guide element 115 includes a second groove element 116, which has a second groove 117 extending in the tube height direction Dih, and a second convex element 118 that enters the second groove 117 and is relatively movable in the tube height direction Dih with respect to the second groove 117. The second groove element 116 is attached to a bottom surface that defines a surface of the second blade air channel 85 on the first blade height side Dh1, on the second channel-defining surface 85p (see Figure 6). Fig. 4) The second convex element 118 is arranged to engage in the second groove 117 of the second groove element 116 and is attached to the sealing plate section 98 of the second insert 95. Therefore, the second guide element 115 allows displacement of the second insert 95 in the pipe height direction Dih and controls displacement of the second insert 95 in a direction perpendicular to the pipe height direction Dih.

[0059] The cooling air Ac flows from the radial outer surface Dro of the outer casing 60o into the cavity 72 of the outer casing 60o. Furthermore, the cooling air Ac flows from the radial inner surface Dri of the inner casing 60i into the cavity 72 of the inner casing 60i. The cooling air Ac is, for example, air compressed by the compressor 20.

[0060] The cooling air Ac flowing into the cavity 72 of the outer casing 60° cools the outer casing 60°. The cooling air Ac particularly cools the gas path surface of the outer casing 60°.

[0061] A section of the cooling air Ac, flowing into the cavity 72 of the outer casing 60o, flows from the opening 80fo of the leading blade air channel 80f into the leading blade air channel 80f. The cooling air Ac performs convection cooling in a section around the leading blade air channel 80f in the blade body 51. Furthermore, the cooling air Ac is expelled from the multiple leading exhaust holes 80fa into the combustion gas channel 49 towards the axial upstream side Dau. As it flows through the multiple leading exhaust holes 80fa, the cooling air Ac performs convection cooling in a section around the multiple leading exhaust holes 80fa.A section of the cooling air Ac, which is expelled into the combustion gas channel 49, prevents a front section of the blade surface, which contains the leading edge 52 of the blade body 51, from being exposed to the combustion gas G, and prevents the front section of the blade surface from being heated by the combustion gas G.

[0062] The other section of the cooling air Ac, which flows into the cavity 72 of the outer casing 60o, flows from the opening 80bo of the rear blade air channel 80b into the rear blade air channel 80b. The cooling air Ac performs convection cooling in a section around the rear blade air channel 80b in the blade body 51. Furthermore, the cooling air Ac is expelled from the multiple rear exhaust holes 80ba into the combustion gas channel 49 towards the axial downstream side Dau. As it flows through the multiple rear exhaust holes 80ba, the cooling air Ac performs convection cooling in a section around the multiple rear exhaust holes 80ba.A section of the cooling air Ac, which is expelled into the combustion gas channel 49, prevents a rear section of the blade surface, which includes the trailing edge 53 of the blade body 51, from being exposed to the combustion gas G and prevents the rear section of the blade surface from being heated by the combustion gas G. Furthermore, a section of the cooling air Ac, which is expelled into the combustion gas channel 49, prevents an eddy current from forming on the axial downstream side Dad of the blade body 51.

[0063] The cooling air Ac flowing into the cavity 72 of the inner casing 60i cools the inner casing 60i. The cooling air Ac particularly cools the gas path surface 64 of the inner casing 60i.

[0064] The cooling air Ac flowing into the cavity 72 of the inner casing 60i flows from the first opening 82f of the first blade air channel 81 and the insert opening 90o of the first insert 90 into the outer circumferential plate section 91 of the first insert 90. The cooling air Ac flowing into the outer circumferential plate section 91 is expelled from the several impact holes 92 formed on the outer circumferential plate section 91 to the outer circumferential side of the outer circumferential plate section 91 and flows into the first blade-internal cavity C1. At the first channel-defining surface 81p, the cooling air Ac collides with a section that has a back-to-back relationship with the pressure-side first blade surface section 55f, and with a section that has a back-to-back relationship with the suction-side first blade surface section 54f, and performs impingement cooling on these sections.Impingement cooling exhibits a higher cooling effect on a cooling target compared to convection cooling. The distance between the cooling air outlet Ac and the surface with which the expelled cooling air Ac collides influences the cooling effect of impingement cooling. Therefore, the present embodiment is provided with the first guide element 110, which controls the displacement of the first insert 90 in the direction perpendicular to the pipe height direction Dih, while simultaneously allowing displacement of the first insert 90 in the pipe height direction Dih.

[0065] In the present embodiment, the first groove element 111 of the first guide element 110 is attached to the first channel-defining surface 81p, and the first convex element 113 of the first guide element 110 is attached to the outer circumferential plate section 91 of the first insert 90. However, the first groove element 111 can be attached to the outer circumferential plate section 91 of the first insert 90, and the first convex element 113 can be attached to the first channel-defining surface 81p. Furthermore, one element of the first groove element 111 and the first convex element 113 can be attached to the first insert 90, and the other element can be attached to the end cover 100. However, the end cover 100 has a lower stiffness compared to the blade body 51.Therefore, from the point of view of controlling the displacement of the first insert 90 in the direction perpendicular to the pipe height direction Dih, it is preferred to attach the other element to one side of the blade body 51.

[0066] A portion of the cooling air Ac flowing into the first internal blade cavity C1 is expelled into the combustion gas channel 49 from the multiple pressure-side first exhaust holes 83pf and the multiple suction-side first exhaust holes 83nf. The cooling air Ac expelled from the multiple pressure-side first exhaust holes 83pf performs film cooling primarily on a downstream section of the pressure-side first blade surface section 55f on the blade surface. Furthermore, the cooling air Ac expelled from the multiple suction-side first exhaust holes 83nf performs film cooling primarily on a downstream section of the suction-side first blade surface section 54f on the blade surface.

[0067] The remaining portion of the cooling air Ac, which flows into the first blade cavity C1, flows within the first blade cavity C1 towards the radial outer side Dro, which is the second blade height side Dh2, flows out of the second opening 82s of the first blade air channel 81 and flows into the end cover 100. The cooling air Ac carries out convection cooling around the first blade cavity C1 in the blade body 51 in a process of flowing within the first blade cavity C1.

[0068] The cooling air Ac flowing into the end cover 100 flows from the opening 86 of the second blade air channel 85 and the insert opening 95o of the second insert 95 into the outer circumferential plate section 96 of the second insert 95. The cooling air Ac flowing into the outer circumferential plate section 96 is expelled from the several impact holes 97 formed on the outer circumferential plate section 96 to the outer circumferential side of the outer circumferential plate section 96 and flows into the second blade-internal cavity C2. At the second channel-defining surface 85p, the cooling air Ac collides with a section that has a back-to-back relationship with the pressure-side second blade surface section 55s and a section that has a back-to-back relationship with the suction-side second blade surface section 54s, and performs the impact cooling on these sections.As described above, the distance between the cooling air outlet Ac and the surface with which the cooling air Ac discharged from the outlet collides affects the cooling effect during impingement cooling. Therefore, the present embodiment is provided with the first guide element 110, which controls the displacement of the second insert 95 in the direction perpendicular to the pipe height direction Dih, while simultaneously allowing the displacement of the second insert 95 in the pipe height direction Dih.

[0069] In the present embodiment, the second groove element 116 of the second guide element 115 is attached to the second channel-defining surface 85p, and the second convex element 118 of the second guide element 115 is attached to the sealing plate section 98 of the second insert 95. However, the second groove element 116 can also be attached to the sealing plate section 98 of the second insert 95, and the second convex element 118 can also be attached to the second channel-defining surface 85p.

[0070] The cooling air Ac flowing into the second internal cavity C2 of the blade is expelled into the combustion gas channel 49 from the multiple pressure-side second exhaust ports 87ps and the multiple suction-side second exhaust ports 87ns. The cooling air Ac expelled from the multiple pressure-side second exhaust ports 87ps primarily performs film cooling on a downstream section of the pressure-side second blade surface section 55s on the blade surface. Furthermore, the cooling air Ac expelled from the multiple suction-side second exhaust ports 87ns primarily performs film cooling on a downstream section of the suction-side second blade surface section 54s on the blade surface.

[0071] As described above, in the present embodiment, the cooling air Ac flowing into the first insert 90 arranged within the first blade air channel 81 performs impingement cooling on the first channel-defining surface 81p. Furthermore, a portion of the cooling air Ac performs film cooling on the downstream section of the pressure-side first blade surface section 55f and the downstream section of the suction-side second blade surface section 54s, and the remaining portion of the cooling air Ac performs convection cooling around the first internal blade cavity C1 in the blade body 51 by flowing within the first internal blade cavity C1. In the present embodiment, the remaining portion of the cooling air Ac flows into the second insert 95, which is arranged within the second blade air channel 85.The cooling air Ac flowing into the second insert 95 performs impingement cooling on the second channel-defining surface 85p. Furthermore, the cooling air Ac performs film cooling on the downstream section of the pressure-side second blade surface section 55s and the downstream section of the suction-side second blade surface section 54s. Therefore, in the present embodiment, the stator blade 50 can be cooled more efficiently, and the consumption of cooling air Ac can be reduced compared to when the cooling air Ac flowing into an insert is expelled to the combustion gas channel immediately after the cooling air Ac has performed impingement cooling on the inside of the blade body. [Second embodiment of stator blade]

[0072] A second embodiment of the stator blade according to the present invention is described below with reference to Fig. 7 and Fig. 8 described. Fig. Figure 7 is a sectional view along a plane perpendicular to the axis Ar of the stator blade. Furthermore, Fig. 8 a sectional view along line VIII-VIII in Fig. 7.

[0073] As in Fig. Figure 7 shows that a stator blade 50a of the present embodiment also includes a blade body 51a, the inner casing 60i and the outer casing 60o. The inner casing 60i and the outer casing 60o of the present embodiment are the same as the inner casing 60i and the outer casing 60o of the first embodiment.

[0074] As in Fig. 7 and Fig. As shown in Figure 8, the blade body 51a of the present embodiment, like the blade body 51 of the first embodiment, has multiple blade air channels 80. Of these multiple blade air channels 80, the one closest to the axial upstream side Dau forms the leading blade air channel 80f, and the one closest to the axial downstream side Dad forms the trailing blade air channel 80b. The configuration of the leading blade air channel 80f is the same as that of the leading blade air channel 80f in the first embodiment. Furthermore, the configuration of the trailing blade air channel 80b is the same as that of the trailing blade air channel 80b in the first embodiment.Furthermore, of the several blade air channels 80, two blade air channels 80 between the front blade air channel 80f and the rear blade air channel 80b form inter-blade air channels 80ma. Unlike the two inter-blade air channels 80m of the first embodiment, the two inter-blade air channels 80ma are oriented in the circumferential direction Dc. Of the two inter-blade air channels 80ma, the inter-blade air channel 80ma on the circumferential pressure side Dcp is designated as a first blade air channel 81a, and the inter-blade air channel 80ma on the circumferential suction side Den is designated as a second blade air channel 85a.

[0075] The first blade air channel 81a has two open ends: one on the radial inner side Dri, which is the first blade height side Dh1, and one on the radial outer side Dro, which is the second blade height side Dh2. The first opening 82f, which is an opening on the radial inner side Dri of the first blade air channel 81a, is open at the counter-gas path surface 65 of the inner casing 60i. Furthermore, the second opening 82s, which is an opening on the radial outer side Dro of the first blade air channel 81a, is open at the counter-gas path surface 65 of the outer casing 60o. The blade body 51a has several pressure-side first ejection holes 83pf that extend from the first channel-defining surface 81p, which defines the first blade air channel 81a of the blade body 51a, to the pressure-side first blade surface section 55f, which is a section of the pressure surface 55.The pressure-side first blade surface section 55f is a section which has a back-to-back relationship with the first blade air channel 81a on the pressure surface 55 of the blade body 51a.

[0076] In the second blade air channel 85a, one end on the radial inner side Dri, which is the first blade height side Dh1, is closed, and one end on the radial outer side Dro, which is the second blade height side Dh2, is open. The opening 86 of the second blade air channel 85a is open at the counter-gas path surface 65 of the outer casing 60o. The blade body 51a has several suction-side second exhaust holes 87ns that extend from the second channel-defining surface 85p, which defines the second blade air channel 85a of the blade body 51a, to the suction-side second blade surface section 54s, which is a section of the suction surface 54. The suction-side second blade surface section 54s is a section that has a back-to-back relationship with the second blade air channel 85a on the suction surface 54 of the blade body 51a.

[0077] In the present embodiment, the end on the radial outer side Dro, which is the second blade height side Dh2, is also open in both the first blade air channel 81a and the second blade air channel 85a.

[0078] The stator blade 50a of the present embodiment further comprises a first insert 90a, a second insert 95a, an end cover 100a, the several first guide elements 110 and the second guide element 115.

[0079] The first insert 90a is arranged within the first blade air channel 81a, and the second insert 95a is arranged within the second blade air channel 85a. As with the first insert 90 of the first embodiment, the first insert 90a includes the outer circumferential plate section 91, the sealing plate section 93, and the flange section 94. Furthermore, the second insert 95a, as with the second insert 95 of the first embodiment, includes the outer circumferential plate section 96, the sealing plate section 98, and the flange section 99. The outer circumferential plate sections 91 and 96 of the first insert 90a and the second insert 95a form a tubular shape and extend in the vertical direction Dih. The sealing plate sections 93 and 98 close the ends of the outer circumferential plate sections 91 and 96 on the vertical sealing side Dih1.The sealing plate section is not provided at the end sections of the outer circumferential plate sections 91 and 96 on the pipe height opening side Dih2. Therefore, the insert openings 90° and 95° for introducing the cooling air Ac into the outer circumferential plate sections 91 and 96 are formed at the end sections of the outer circumferential plate sections 91 and 96 on the opening side of the pipe height Dih2. The flange sections 94 and 99 extend from the ends on the pipe height opening side Dih2 along all outer circumferential surfaces of the outer circumferential plate sections 91 and 96 towards the outer circumferential side.

[0080] The outer circumferential plate section 91 of the first insert 90a is arranged within the first blade air channel 81a such that the pipe height opening side Dih2 faces the first blade height side Dh1 and a gap exists between the outer circumferential plate section 91 and the first channel-defining surface 81p of the blade body 51a, which defines the first blade air channel 81a. The flange section 94 is connected to an edge of the first opening 82f of the first blade air channel 81a to close the gap between the outer circumferential plate section 91 and the first channel-defining surface 81p. The gap between the outer circumferential side of the outer circumferential plate section 91 of the first insert 90a and the first channel-defining surface 81p forms the first blade-internal cavity C1 into which the cooling air Ac flows.

[0081] The multiple impact holes 92, which penetrate from the inside to the outside of the outer circumferential plate section 91, are formed on a section of the outer circumferential plate section 91 of the first insert 90a facing the pressure-side first blade surface section 55f.

[0082] The outer circumferential plate section 96 of the second insert 95a is arranged within the second blade air channel 85a such that the pipe height opening side Dih2 faces the second blade height side Dh2, and a gap exists between the outer circumferential plate sections 91 and 96 and the second channel-defining surface 85p of the blade body 51a, which defines the second blade air channel 85a. The flange sections 94 and 99 are connected to the edge of the opening of the second blade air channel 85a to close the gap between the outer circumferential plate sections 91 and 96 and the second channel-defining surface 85p. The gap between the outer circumferential side of the outer circumferential plate sections 91 and 96 of the second insert 95a and the second channel-defining surface 85p forms the second blade-internal cavity C2 into which the cooling air Ac flows.

[0083] The multiple impact holes 97, which penetrate from the inside to the outside of the outer circumferential plate section 96, are formed on a section of the outer circumferential plate section 96 of the second insert 95a facing the suction-side second blade surface section 54s.

[0084] The second blade surface section 54s is a section of the suction surface 54, and the first blade surface section 55f is a section of the pressure surface 55. Therefore, a position of the second blade surface section 54s is a position where, while the gas turbine 10 is driven, the pressure of the section along the second blade surface section 54s outside the blade body 51a is lower than the pressure of the section along the first blade surface section 55f outside the blade body 51a.

[0085] As with the end cover 100 of the first embodiment, the end cover 100a includes a cover plate section 101a and the outer circumferential plate section 102. However, in the present embodiment, the orientation of the second blade air channel 85a relative to the first blade air channel 81a differs from that of the first embodiment. Therefore, the shape of the cover plate section 101a differs from the shape of the cover plate section 101 of the first embodiment. As with the end cover 100 of the first embodiment, the end cover 100a can also direct the cooling air Ac, which flows from the second opening 82s of the first blade air channel 81a into the second blade air channel 85a, away from the opening 86 of the second blade air channel 85a.

[0086] The first guide element 110 is the same as the first guide element 110 of the first embodiment. Furthermore, the second guide element 115 is the same as the second guide element 115 of the first embodiment.

[0087] A flow of cooling air Ac in the present embodiment is the same as a flow of cooling air Ac in the first embodiment. Therefore, in the present embodiment, the cooling air Ac flowing into the first insert 90a arranged within the first blade air channel 81a also performs impingement cooling on the first channel-defining surface 81p. Furthermore, a portion of the cooling air Ac performs film cooling on a downstream section of the pressure-side first blade surface section 55f, and the remaining portion performs convection cooling around the first internal blade cavity C1 in the blade body 51a by flowing within the first internal blade cavity C1. The remaining portion of the cooling air Ac flows into the second insert 95a, which is arranged within the second blade air channel 85a.The cooling air Ac flowing into the second insert 95a performs impingement cooling on the second channel-defining surface 85p. Furthermore, the cooling air Ac performs film cooling on a downstream section of the suction-side second blade surface section 54s. Therefore, in the present embodiment, the stator blade 50a can be cooled more efficiently, and the consumption of cooling air Ac can be reduced compared to when the cooling air Ac flowing into an insert is expelled to the combustion gas channel immediately after the cooling air Ac has performed impingement cooling on the inside of the blade body.

[0088] As described above, the second blade air channel can be arranged on the axial downstream side Dad of the first blade air channel 81, as in the first embodiment, or, as in the present embodiment, the second blade air channel can be arranged on the circumferential suction side Den of the first blade air channel 81a. [First modification example of stator blade]

[0089] Below is a first modification example of the first embodiment of the stator blade according to the present invention with reference to Fig. 9 described.

[0090] A stator blade 50b of the present modification example differs from the stator blade 50 of the first embodiment in a shape and fastening method of a first insert 90b and a second insert 95b, and other configurations are the same.

[0091] The first insert 90b of the present modification example comprises the outer circumferential plate section 91, the sealing plate section 93, and a flange section 94b. The outer circumferential plate section 91 has a tubular shape and extends in the pipe height direction Dih. The sealing plate section 93 closes one end of the outer circumferential plate section 91 on the pipe height sealing side Dih1. However, the sealing plate section is not provided at an end section of the outer circumferential plate section 91 on the pipe height opening side Dih2. Therefore, the insert opening 90o for introducing the cooling air Ac into the outer circumferential plate section 91 is formed at the end section of the outer circumferential plate section 91 on the pipe height opening side Dih2.In contrast to the flange section 94 of the first insert 90 in the first embodiment, the flange section 94b extends from the end on the pipe height sealing side Dih1 towards the outer circumferential side at a section of the outer circumferential surface of the outer circumferential plate section 91. Therefore, the flange section 94b of the first insert 90b has a shape in which a section is cut out.

[0092] The outer circumferential plate section 91 of the first insert 90b is arranged within the first blade air channel 81 such that the pipe height opening side Dih2 faces the first blade height side Dh1 and a gap exists between the outer circumferential plate section 91 and the first channel-defining surface 81p. An outer edge of the flange section 94b is connected to the area surrounding the second opening 82s of the first blade air channel 81. In contrast to the first insert 90 in the first embodiment, the pipe height sealing side Dih1 of the first insert 90b of the present modification example is therefore attached to the blade body 51. A sealing flange 84, which projects towards a central side of the first blade air channel 81 and faces the outer circumferential plate section 91 of the first insert 90b, is provided in an edge of the first opening 82f of the first blade air channel 81.The sealing flange 84 serves to prevent the cooling air Ac flowing into the cavity 72 of the inner casing 60i from flowing into the first internal cavity C1 within the first blade air channel 81. The sealing flange 84 is not attached to the outer circumferential plate section 91 of the first insert 90b in order to allow the displacement of the first insert 90b in the blade height direction Dh.

[0093] Of the outer circumferential plate section 91 of the first insert 90b, a section facing the pressure-side first blade surface section 55f and a section facing the suction-side first blade surface section 54f, as in the outer circumferential plate section 91 of the first insert 90 in the first embodiment, have the several impact holes 92 that penetrate from the inside to the outside of the outer circumferential plate section 91.

[0094] The second insert 95b of the present modification example contains the outer circumferential plate section 96 and the sealing plate section 98, and does not include a flange section. The outer circumferential plate section 96 has a tubular shape and extends in the pipe height direction Dih. The sealing plate section 98 closes one end of the outer circumferential plate section 96 on the pipe height sealing side Dih1. However, the sealing plate section is not provided at an end section of the outer circumferential plate section 96 on the pipe height opening side Dih2. Therefore, the insert opening 95o for introducing the cooling air Ac into the outer circumferential plate section 96 is formed at the end section of the outer circumferential plate section 96 on the pipe height opening side Dih2.

[0095] The outer circumferential plate section 96 of the second insert 95b is arranged within the second blade air channel 85 such that the pipe height opening side Dih2 faces the second blade height side Dh2, and a gap exists between the outer circumferential plate section 96 and the second channel-defining surface 85p. The sealing plate section 98 of the second insert 95b is attached to a base surface, which is a surface of the second blade air channel 85 on the first blade height side Dh1, on the second channel-defining surface 85p. In contrast to the second insert 95 in the first embodiment, in the second insert 95b of the present modification example, the pipe height sealing side Dih1 is fixed to the blade body 51.A sealing flange 88, projecting towards a central side of the second blade air channel 85 and facing the outer circumferential plate section 96 of the second insert 95b, is provided in an edge of the opening 86 of the second blade air channel 85. The sealing flange 88 serves to prevent the cooling air Ac within the end cover 100 from flowing into the second blade-internal cavity C2 within the second blade air channel 85. The sealing flange 88 is not attached to the outer circumferential plate section 96 of the second insert 95b in order to allow displacement of the second insert 95b in the blade height direction Dh.

[0096] Of the outer circumferential plate section 96 of the second insert 95b, a section facing the pressure-side second blade surface section 55s and a section facing the suction-side second blade surface section 54s, as with the outer circumferential plate section 96 of the first insert 90 in the first embodiment, have the several impact holes 97 that penetrate from the inside to the outside of the outer circumferential plate section 96.

[0097] In the present modification example, the cooling air Ac also flows from the radial outer surface Dro of the outer casing 60o into the cavity 72 of the outer casing 60o. In addition, the cooling air Ac flows from the radial inner surface Dri of the inner casing 60i into the cavity 72 of the inner casing 60i.

[0098] As in the first embodiment, a portion of the cooling air Ac, which flows into the cavity 72 of the outer casing 60o, flows from the opening 80fo of the front blade air channel 80f into the front blade air channel 80f. Furthermore, the other portion of the cooling air Ac, which flows into the cavity 72 of the outer casing 60o, also flows, as in the first embodiment, from the opening 80bo of the rear blade air channel 80b into the rear blade air channel 80b.

[0099] The majority of the cooling air Ac flowing into the cavity 72 of the inner casing 60i flows from the first opening 82f of the first blade air channel 81 and the insert opening 90o of the first insert 90b into the outer circumferential plate section 91 of the first insert 90b. A small amount of the cooling air Ac, which flows into the cavity 72 of the inner casing 60i, flows from a gap between the sealing flange 84, which is provided in an edge of the first opening 82f of the first blade air channel 81, and the outer circumferential plate section 91 of the first insert 90b into the first blade-internal cavity C1 within the first blade air channel 81. The cooling air Ac flowing into the outer circumferential plate section 91 is expelled from the several impact holes 92 formed on the outer circumferential plate section 91 to the outer circumferential side of the outer circumferential plate section 91 and flows into the first blade-internal cavity C1.At the first channel-defining surface 81p, the cooling air Ac collides with a section that has a back-to-back relationship with the pressure-side first blade surface section 55f, and with a section that has a back-to-back relationship with the suction-side first blade surface section 54f, and performs impingement cooling on these sections.

[0100] A portion of the cooling air Ac flowing into the first blade cavity C1 is expelled from the multiple pressure-side first exhaust holes 83pf and the multiple suction-side first exhaust holes 83nf into the combustion gas channel 49. The remaining portion of the cooling air Ac flowing into the first blade cavity C1 flows within the first blade cavity C1 to the radial outer side Dro, which is the second blade height side Dh2, and flows through a cutout section of the flange section 94b of the first insert 90b and the second opening 82s of the first blade air channel 81 into the end cover 100.

[0101] Most of the cooling air Ac flowing into the end cover 100 flows from the opening 86 of the second blade air channel 85 and the insert opening 95o of the second insert 95b into the outer circumferential plate section 96 of the second insert 95b. A small amount of the cooling air Ac flowing into the end cover 100, however, flows from a gap between the sealing flange 88, which is provided in an edge of the opening 86 of the second blade air channel 85, and the outer circumferential plate section 96 of the second insert 95b into the second blade-internal cavity C2 within the second blade air channel 85. The cooling air Ac flowing into the outer circumferential plate section 96 is expelled from the several impact holes 97 formed on the outer circumferential plate section 96 to the outer circumferential side of the outer circumferential plate section 96 and flows into the second blade-internal cavity C2.At the second channel-defining surface 85p, the cooling air Ac collides with a section that has a back-to-back relationship with the pressure-side second blade surface section 55s, and with a section that has a back-to-back relationship with the suction-side second blade surface section 54s, and performs the impingement cooling on these sections.

[0102] The cooling air Ac flowing into the second internal cavity C2 of the blade is expelled from the several pressure-side second discharge holes 87ps and the several suction-side second discharge holes 87ns into the combustion gas channel 49.

[0103] In the present modification example, the cooling air Ac flowing into the first insert 90b, which is arranged within the first blade air channel 81, also performs impingement cooling at the first channel-defining surface 81p, as in the first embodiment. Furthermore, a portion of the cooling air Ac flows into the second insert 95b to perform impingement cooling at the second channel-defining surface 85p. Therefore, in the present modification example, as in the first embodiment, the stator blade 50b can be cooled more efficiently, and the consumption of cooling air Ac can be reduced compared to when the cooling air Ac flowing into an insert is expelled to the combustion gas channel immediately after the cooling air Ac has performed impingement cooling on the inside of the blade body.

[0104] In the present modification example, however, a section of the cooling air Ac, which flows into the cavity 72 of the inner casing 60i, flows from the gap between the sealing flange 84, which is provided in the edge of the first opening 82f of the first blade air channel 81, and the outer circumferential plate section 91 of the first insert 90b into the first blade-internal cavity C1, without carrying out the impingement cooling at the first channel-defining surface 81p as described above. Furthermore, in the present modification example, a section of the cooling air Ac flowing into the end cover 100 flows from the gap between the sealing flange 88, which is provided in the edge of the opening 86 of the second blade air channel 85, and the outer circumferential plate section 96 of the second insert 95b into the second blade-internal cavity C2, without performing the impact cooling at the second channel-defining surface 85p as described above.Therefore, in the present modification example, the effect of impingement cooling of the blade body 51 is lower than in the first embodiment. In other words, the effect of impingement cooling of the blade body 51 in the first embodiment is higher than in the present modification example.

[0105] As described above, as in the first embodiment, the pipe height opening side Dih2 can be attached to the blade body 51 in the first insert 90b and the second insert 95b, or as in the present modification example, the pipe height sealing side Dih1 can be attached to the blade body 51.

[0106] Although the present modification example is a modification example of the first embodiment, the second embodiment can be configured in the same way as the present modification example. [Second modification example of stator blade]

[0107] Below, a second modification example of the first embodiment of the stator blade according to the present invention is described with reference to Fig. 10 described.

[0108] A stator blade 50c of the present modification example differs from the stator blade 50 of the first embodiment in that an opening of a first blade air channel 81c, an opening of a second blade air channel 85c, and an end cover 100c are arranged differently. Furthermore, the stator blade 50c of the present modification example differs from the stator blade 50 of the first embodiment in that the shape and fastening method of a first insert 90c and a fastening method of a second insert 95c differ, while other configurations are the same.

[0109] Both the first blade air channel 81c and the second blade air channel 85c of the present modification example extend in the blade height direction Dh, as in the first embodiment. However, in the first blade air channel 81c of the present modification example, one end on the radial inner side Dri, which is the first blade height side Dh1, is open, and one end on the radial outer side Dro, which is the second blade height side Dh2, is closed. The opening 82f on the radial inner side Dri of the first blade air channel 81c is open at the counter-gas path surface 65 of the inner casing 60i. Furthermore, in the second blade air channel 85c, one end on the radial inner side Dri, which is the first blade height side Dh1, is open, and one end on the radial outer side Dro, which is the second blade height side Dh2, is closed.An opening 86c of the second blade air channel 85c is open at the counter-gas path surface 65 of the inner casing 60i.

[0110] As described above, in the present modification example, the end on the radial inside Dri, which is the first blade height side Dh1, is open in both the first blade air channel 81c and the second blade air channel 85c.

[0111] The first insert 90c of the present modification example comprises the outer circumferential plate section 91, the sealing plate section 93, and a flange section 94c. The outer circumferential plate section 91 has a tubular shape and extends in the pipe height direction Dih. The sealing plate section 93 closes one end of the outer circumferential plate section 91 on the pipe height sealing side Dih1. However, the sealing plate section is not provided at an end section of the outer circumferential plate section 91 on the pipe height opening side Dih2. Therefore, the insert opening 90o for introducing the cooling air Ac into the outer circumferential plate section 91 is formed at the end section of the outer circumferential plate section 91 on the pipe height opening side Dih2.In contrast to the flange section 94 of the first insert 90 in the first embodiment, the flange section 94c is a section of the outer circumferential surface of the outer circumferential plate section 91 and extends from a position located a predetermined distance from the end of the pipe-height opening side Dih2 of the outer circumferential plate section 91 to the pipe-height sealing side Dih1, towards the outer circumferential side. Therefore, the flange section 94c of the first insert 90c has a shape in which a section is cut out. The predetermined distance is greater than the height of the outer circumferential plate section 103 of the end cover 100.

[0112] The outer circumferential plate section 91 of the first insert 90c is arranged within the first blade air channel 81c such that the pipe height opening side Dih2 faces the first blade height side Dh1 and a gap exists between the outer circumferential plate section 91 and the first channel-defining surface 81p. The flange section 94c is connected to the edge of the first opening 82f of the first blade air channel 81c.

[0113] As with the second insert 95 of the first embodiment, the second insert 95c of the present modification example includes the outer circumferential plate section 96, the sealing plate section 98, and the flange section 99. However, unlike the first embodiment, the outer circumferential plate section 96 of the second insert 95c of the present modification example is arranged within the second blade air channel 85c such that the pipe height opening side Dih2 faces the first blade height side Dh1, and a gap exists between the outer circumferential plate section 96 and the second channel-defining surface 85p of the blade body 51, which defines the second blade air channel 85c. The flange section 99 is connected to the edge of the opening 86c of the second blade air channel 85c to close the gap between the outer circumferential plate section 96 and the second channel-defining surface 85p.

[0114] As with the end cover 100 of the first embodiment, the end cover 100c includes the cover plate section 101 and the outer circumferential plate section 102. However, the end cover 100c of the present modification example is arranged on the first blade height side Dh1 of the blade body 51. The cover plate section 101 of the end cover 100c faces a region in which the first blade air channel 81c and the second blade air channel 85c are arranged at a distance in the blade height direction Dh on the counter-gas path surface 65 of the inner casing 60i. The outer circumferential plate section 102 of the end cover 100c is connected to an edge of the region in which the first blade air channel 81c and the second blade air channel 85c are present on the counter-gas path surface 65 of the inner casing 60i.The pipe height opening side Dih2 of the outer circumferential plate section 91 of the first insert 90c protrudes from the cover plate section 101 of the end cover 100c to the radial inner side Dri.

[0115] In the present modification example, the cooling air Ac also flows from the radial outer surface Dro of the outer casing 60o into the cavity 72 of the outer casing 60o. In addition, the cooling air Ac flows from the radial inner surface Dri of the inner casing 60i into the cavity 72 of the inner casing 60i.

[0116] As in the first embodiment, a portion of the cooling air Ac, which flows into the cavity 72 of the outer casing 60o, flows from the opening 80fo of the front blade air channel 80f into the front blade air channel 80f. Furthermore, the other portion of the cooling air Ac, which flows into the cavity 72 of the outer casing 60o, also flows, as in the first embodiment, from the opening 80bo of the rear blade air channel 80b into the rear blade air channel 80b.

[0117] The cooling air Ac flowing into the cavity 72 of the inner casing 60i flows from the insert opening 90o of the first insert 90c into the outer circumferential plate section 91 of the first insert 90c. The cooling air Ac flowing into the outer circumferential plate section 91 is expelled from the several impact holes 92 formed on the outer circumferential plate section 91 to the outer circumferential side of the outer circumferential plate section 91 and flows into the first blade-internal cavity C1. The cooling air Ac collides with the first channel-defining surface 81p and performs the impact cooling at the first channel-defining surface 81p.

[0118] A portion of the cooling air Ac flowing into the first blade cavity C1 is expelled from the multiple pressure-side first exhaust holes 83pf and the multiple suction-side first exhaust holes 83nf into the combustion gas channel 49. The remaining portion of the cooling air Ac flowing into the first blade cavity C1 flows within the first blade cavity C1 towards the radial inner side Dri, which is the first blade height side Dh1, and flows through the cutout section of the flange section 94c of the first insert 90c and the opening 82f of the first blade air channel 81c into the end cover 100c.

[0119] The cooling air Ac, flowing into the end cover 100c, flows from the opening 86c of the second blade air channel 85c and the insert opening 95o of the second insert 95 into the outer circumferential plate section 96 of the second insert 95c. The cooling air Ac flowing into the outer circumferential plate section 96 is expelled from the several impact holes 97 formed on the outer circumferential plate section 96 to the outer circumferential side of the outer circumferential plate section 96 and flows into the second blade-internal cavity C2. The cooling air Ac collides with the second channel-defining surface 85p and performs the impact cooling at the second channel-defining surface 85p.

[0120] The cooling air Ac flowing into the second internal cavity C2 of the blade is expelled from the several pressure-side second discharge holes 87ps and the several suction-side second discharge holes 87ns into the combustion gas channel 49.

[0121] In the present modification example, the cooling air Ac flowing into the first insert 90c, which is arranged within the first blade air channel 81c, also performs impingement cooling at the first channel-defining surface 81p, as in the first embodiment. Furthermore, a portion of the cooling air Ac flows into the second insert 95c and performs impingement cooling at the second channel-defining surface 85p. Therefore, in the present modification example, as in the first embodiment, the stator blade 50c can be cooled more efficiently, and the consumption of cooling air Ac can be reduced compared to when the cooling air Ac flowing into an insert is expelled to the combustion gas channel immediately after the cooling air Ac has performed impingement cooling on the inside of the blade body.

[0122] In the present modification example, the cooling air Ac flowing into the first insert 90c flows to the second blade height side Dh2 within the first insert 90c and is expelled from the baffle hole 92. The cooling air Ac then flows to the first blade height side Dh1 within the first internal blade cavity C1 and flows into the second insert 95c. Therefore, in this modification example, the cooling air Ac moves back and forth in the blade height direction Dh within the first blade air channel 81c. Consequently, the length of the flow path through which the cooling air Ac flows is increased, and the flow resistance of the cooling air Ac increases. As a result, in this modification example, the pressure of the cooling air Ac flowing into the second insert 95c decreases. Therefore, in this modification example, the effect of impingement cooling of the blade body 51c is lower than in the first embodiment.In other words, the effect of impact cooling of the blade body 51 of the first embodiment is higher than that of the present modification example.

[0123] As described above, of the first blade height side Dh1 and the second blade height side Dh2, one side on which both the first blade air channel and the second blade air channel are open can be the second blade height side Dh2, as in the first embodiment, or it can be the first blade height side Dh1, as in the present modification example. Furthermore, the tube height opening side Dih of the second insert can face the second blade height side Dh2, as in the first embodiment, or it can face the first blade height side Dh1, as in the present modification example.

[0124] Although the present modification example is a modification example of the first embodiment, the second embodiment can be configured in the same way as the present modification example. [Third modification example of stator blade]

[0125] Below, a third modification example of the first embodiment of the stator blade according to the present invention is described with reference to Fig. 11 described.

[0126] A stator blade 50d of the present modification example is a stator blade in which a baffle plate 78 is added to the inside of the outer casing 60o and to the inside of the inner casing 60i in the stator blade 50 of the first embodiment.

[0127] The baffle plate 78 within the outer casing 60° divides the cavity 72 of the outer casing 60° into two spaces in the blade height direction Dh. The baffle plate 78 has several baffle holes 79 that penetrate in the blade height direction Dh.

[0128] The baffle plate 78 within the inner casing 60i divides the cavity 72 of the inner casing 60i into two spaces in the blade height direction Dh. The baffle plate 78 has several baffle holes 79 that penetrate in the blade height direction Dh.

[0129] The cooling air Ac flowing into the cavity 72 of the outer casing 60o is expelled from the multiple impact holes 79 of the impact plate 78, collides with the counter-gas path surface 65 of the outer casing 60o, and performs the impingement cooling at the counter-gas path surface 65. As in the first embodiment, a portion of the cooling air Ac, which performs the impingement cooling at the counter-gas path surface 65, flows from the opening 80fo of the front blade air channel 80f into the front blade air channel 80f. Furthermore, as in the first embodiment, the other portion of the cooling air Ac, which performs the impingement cooling on the counter-gas path surface 65, flows from the opening 80bo of the rear blade air channel 80b into the rear blade air channel 80b.

[0130] The cooling air Ac flowing into the cavity 72 of the inner casing 60i is expelled from the multiple impact holes 79 of the impact plate 78, collides with the counter-gas path surface 65 of the inner casing 60i, and performs the impact cooling at the counter-gas path surface 65. As in the first embodiment, a portion of the cooling air Ac, which performs the impact cooling at the counter-gas path surface 65, flows into the first insert 90. As in the first embodiment, the cooling air Ac flowing into the first insert 90 performs the impact cooling at the first channel-defining surface 81p and then the impact cooling at the second channel-defining surface 85p.

[0131] As described above, in the present modification example, the cooling air Ac flowing into the cavity 72 of the inner casing 60i can perform impingement cooling on the inside of the stator blade 50d three times. Therefore, in the present modification example, the stator blade 50d can be cooled more efficiently, and the consumption of cooling air Ac can be reduced compared to the first embodiment and each modification thereof.

[0132] Although the present modification example is a modification example of the first embodiment, the impact plate 78 can be added, as in the present modification example, to the second embodiment, the first modification example and the second modification example. [Further modification examples of stator blade]

[0133] In each of the embodiments and modification examples described above, the first blade height side Dh1 is the radial inner side Dri, and the second blade height side Dh2 is the radial outer side Dro. However, the first blade height side Dh1 can be the radial outer side Dro, and the second blade height side Dh2 can be the radial inner side Dri.

[0134] The stator blade of each of the embodiments and modification examples described above contains two blade air channels as the inter-blade air channels 80m, one of which is the first blade air channel and the other the second blade air channel. However, the stator blade may contain three or more blade air channels as the inter-blade air channels 80m, one of which may be used as the first blade air channel and another as the second blade air channel. Furthermore, neither the first blade air channel nor the second blade air channel need be channels between the leading blade air channel 80f and the trailing blade air channel 80b. For example, the first blade air channel may be one of the inter-blade air channels 80m, and the second blade air channel may be the trailing blade air channel 80b.

[0135] All stator blades of the embodiments and modification examples described above are the stator blades that form the first-stage stator blade row 46. However, the stator blade can be a stator blade that forms a stator blade row closer to the axial downstream side Dad than the first-stage stator blade row 46.

[0136] The embodiments and modification examples of the present disclosure have been described in detail above. However, the present disclosure is not limited to the embodiments and modification examples described above. Various additions, changes, replacements, or partial omissions may be made within the scope that does not deviate from the conceptual idea and core of the present disclosure, which are derived from the content defined in the scope of the appended claims and their equivalents. [Additional information]

[0137] For example, in the embodiment and modification example described above, the stator blade is understood as follows.

[0138] (1) According to a first aspect, the stator blade provided in the gas turbine 10 is provided. The stator blade comprises the blade bodies 51, 51a and 51c, which have a blade shape in cross-section and extend in the blade height direction Dh, which has a directional component perpendicular to the cross-section; the first inserts 90, 90a, 90b and 90c; and the second inserts 95, 95a, 95b and 95c, which have a tubular shape, extend in the tube height direction Dih and are arranged within the blade bodies 51, 51a and 51c such that the tube height direction Dih faces the blade height direction Dh; and the end covers 100, 100a and 100c. The blade bodies 51, 51a and 51c contain several blade air channels 80 which extend in the blade height direction Dh within the blade bodies 51, 51a and 51c.Of the several blade air channels 80, both the first blade air channels 81, 81a and 81c and the second blade air channels 85, 85a and 85c have an open end on one blade height side, which is one side of the first blade height side Dh1 and the second blade height side Dh2 in the blade height direction Dh. Both the first inserts 90, 90a, 90b and 90c and the second inserts 95, 95a, 95b and 95c contain the outer circumferential plate sections 91 and 96, which have a tubular shape and extend in the pipe height direction Dih, and the sealing plate sections 93 and 98, which close the ends on the pipe height sealing side Dih1, which is one side of the outer circumferential plate sections 91 and 96 in the pipe height direction Dih from two sides.The outer circumferential plate sections 91 and 96 have several impact holes 92 and 97 that penetrate from the inside to the outside of the tubular outer circumferential plate sections 91 and 96. The pipe height opening side Dih2, which is the other side of the outer circumferential plate sections 91 and 96 in the pipe height direction Dih, is open. The outer circumferential plate section 91 of the first inserts 90, 90a, 90b and 90c has a gap that is present between the outer circumferential plate section 91 of the first insert 90 and the surface 81p defining the first channel of the blade bodies 51, 51a and 51c, which define the first blade air channel 81, and is arranged within the first blade air channel 81, 81a and 81c, so that cooling air Ac flows from the opening of the first inserts 90, 90a, 90b and 90c into the outer circumferential plate section 91.The outer circumferential plate section 96 of the second inserts 95, 95a, 95b and 95c is configured such that the opening side of the pipe height Dih2 of the second inserts 95, 95a, 95b and 95c faces one side of the blade height, has a gap between the outer circumferential plate section 96 of the second inserts 95, 95a, 95b and 95c and the surface 85p defining the second channel of the blade bodies 51, 51a and 51c, which define the second blade air channel 85, and is arranged within the second blade air channels 85, 85a and 85c such that the cooling air Ac flows out of the opening of the second inserts 95, 95a, 95b and 95c.The end covers 100, 100a and 100c are provided on one blade height side of the blade body 51, so that the cooling air Ac, which is expelled from the several impact holes 92 of the first inserts 90, 90a, 90b and 90c between the outer circumferential plate section 91 of the first inserts 90, 90a, 90b, and 90c and the first channel-defining surface 81p, is directed from the opening of the second inserts 95, 95a, 95b and 95c through the opening of the first blade air channel 81 into the second inserts 95, 95a, 95b and 95c, and covers the opening of the first blade air channel 81 and the opening of the second inserts 95, 95a, 95b and 95c.

[0139] In the present aspect, the cooling air Ac flowing into the first inserts 90, 90a, 90b, and 90c, which are arranged within the first blade air channels 81, 81a, and 81c, performs impingement cooling at the first channel-defining surface 81p. Furthermore, at least a portion of the cooling air Ac flows into the second inserts 95, 95a, 95b, and 95c, which are arranged within the second blade air channels 85, 85a, and 85c. The cooling air Ac flowing into the second inserts 95, 95a, 95b, and 95c performs impingement cooling at the second channel-defining surface 85p. Therefore, in the present aspect, the stator blade can be cooled more efficiently, and the consumption of cooling air Ac can be reduced, compared to when the cooling air Ac flowing into an insert is expelled to the combustion gas channel immediately after the cooling air Ac has performed the impact cooling on the inside of the blade body.

[0140] (2) According to a second aspect of the stator blade, in the stator blade according to the first aspect, the blade surfaces that are the outer surfaces of the blade bodies 51, 51a and 51c include the first blade surface sections 54f and 55f, which have a back-to-back positional relationship with the first channel-defining surface 81p, and the second blade surface sections 54s and 55s, which have a back-to-back positional relationship with the second channel-defining surface 85p. The multiple impact holes 92 are formed on the sections of the outer circumferential plate section 91 facing the first blade surface sections 54f and 55f at the first inserts 90, 90a, 90b and 90c. The multiple impact holes 97 are formed on the sections facing the second blade surface sections 54s and 55s of the outer circumferential plate section 96 of the second inserts 95, 95a, 95b and 95c.

[0141] In this aspect, the blade surface exposed to the combustion gas can be effectively cooled.

[0142] (3) According to a third aspect of the stator blade, in the stator blade according to the second aspect, the blade bodies 51, 51a and 51c have the multiple ejection holes 87ns and 87ps, which penetrate from the second channel-defining surface 85p to the second blade surface sections 54s and 55s. The positions of the second blade surface sections 54s and 55s on the blade surface are positions at which the pressure of the section along the second blade surface sections 54s and 55s outside the blade bodies 51, 51a and 51c, while the gas turbine 10 is driven, is lower than the pressure of the section along the first blade surface sections 54f and 55f outside the blade bodies 51, 51a and 51c.

[0143] (4) According to a fourth aspect of the stator blade, in the stator blade according to the third aspect, the blade bodies 51 and 51c contain the leading edge 52, which extends in the blade height direction Dh, the trailing edge 53, which extends in the blade height direction Dh, and the pressure surface 55 and the suction surface 54, which extend in the blade height direction Dh and connect the leading edge 52 and the trailing edge 53. The first blade surface sections 54f and 55f are sections of a blade surface consisting of the pressure surface 55 and the suction surface 54. The second blade surface sections 54s and 55s are located closer to one side of the trailing edge 53 than the first blade surface sections 54f and 55f of the one blade surface.

[0144] (5) According to a fifth aspect of the stator blade, in the stator blade according to the third aspect, the blade body 51a includes the leading edge 52, which extends in the blade height direction Dh, the trailing edge 53, which extends in the blade height direction Dh, and the pressure surface 55 and the suction surface 54, which extend in the blade height direction Dh and connect the leading edge 52 and the trailing edge 53. The first blade surface section 55f is a section of the pressure surface 55. The second blade surface section 54s is a section of the suction surface 54.

[0145] (6) According to a sixth aspect of the stator blade, in the first blade air channels 81 and 81a, one end on the first blade height side Dh1 and one end on the second blade height side Dh2 of the first blade air channels 81 and 81a are open. In the second blade air channels 85 and 85a, one end on the first blade height side Dh1 of the second blade air channels 85 and 85a is closed, and one end on the second blade height side Dh2 is open. The first inserts 90 and 90a contain the flange section 94, which extends from one end on the pipe height opening side Dih2 at the outer circumferential plate section 91 of the first inserts 90 and 90a to the outer circumferential side of the outer circumferential plate section 91 of the first inserts 90 and 90a, extends to the first channel-defining surface 81p and is connected to the blade body 51.

[0146] The second inserts 95 and 95a include the flange section 99, which extends from one end on the pipe height opening side Dih2 at the outer circumferential plate section 96 of the second inserts 95 and 95a to the outer circumferential side of the outer circumferential plate section 96 of the second inserts 95 and 95a, extends to the second channel-defining surface 85p, and is connected to the blade body 51. The outer circumferential plate section 91 of the first inserts 90 and 90a is arranged within the first blade air channels 81 and 81a such that the pipe height opening side Dih2 of the first inserts 90 and 90a faces the first blade height side Dh1. The outer circumferential plate section 96 of the second inserts 95 and 95a is arranged within the second blade air channels 85 and 85a such that the pipe height opening side Dih2 of the second inserts 95 and 95a faces the second blade height side Dh2.

[0147] In the present aspect, the structure of each insert is not complicated, and the effect of impact cooling of the blade body 51 can be improved.

[0148] (7) According to a seventh aspect of the stator blade, the stator blade according to any aspect of the first to sixth aspects further comprises the first guide element 110, which, within the first blade air channels 81, 81a and 81c, enables the displacement of the first inserts 90, 90a, 90b and 90c in the pipe height direction Dih and which controls the displacement of the first inserts 90, 90a, 90b and 90c in a propagation direction of the cross-section of the first inserts 90, 90a, 90b and 90c, and the second guide element 115, which, within the second blade air channels 85, 85a and 85c, enables the displacement of the second inserts 95, 95a, 95b and 95c in the pipe height direction Dih and which controls the displacement of the second inserts 95, 95a, 95b and 95c in a propagation direction of the cross-section the second deployments 95, 95a, 95b and 95c are regulated.

[0149] In the present aspect, even if the gas turbine 10 is driven, such that a difference in thermal deformation amounts exists between the outer circumferential plate sections 91 of the first inserts 90, 90a, 90b and 90c and the first channel-defining surface 81p due to a temperature difference between them, a distance between the outer circumferential plate sections 91 of the first inserts 90, 90a, 90b and 90c and the first channel-defining surface 81p can be kept essentially constant, and a desired effect of impact cooling can be obtained.Furthermore, in the present aspect, even if the gas turbine 10 is driven, so that a difference in thermal deformation amounts exists between the outer circumferential plate sections 96 of the second inserts 95, 95a, 95b and 95c and the second channel-defining surface 85p due to a temperature difference between them, a distance between the outer circumferential plate sections 96 of the second inserts 95, 95a, 95b and 95c and the second channel-defining surface 85p can be kept essentially constant, and a desired effect of impact cooling can be obtained.

[0150] (8) According to an eighth aspect of the stator blade, in the stator blade according to the seventh aspect, the first guide element 110 includes the first groove element 111, which has the first groove 112 extending in the pipe height direction Dih, and the first convex element 113, which enters the inside of the first groove 112 and is relatively movable in the pipe height direction Dih with respect to the first groove 112. One element of the first groove element 111 and the first convex element 113 is attached to the first inserts 90 and 90a, and the other element is attached to the first channel-defining surface 81p. The second guide element 115 contains the second groove element 116, which has the second groove 117 extending in the pipe height direction, and the second convex element 118, which enters the second groove 117 and is relatively movable in the pipe height direction Dih with respect to the second groove 117.One element of the second groove element 116 and of the second convex element 118 is attached to the second inserts 95 and 95a, and the other element is attached to the surface 85p defining the second channel.

[0151] (9) According to a ninth aspect of the stator blade, the stator blade according to the sixth aspect further comprises the first guide element 110, which enables the displacement of the first inserts 90 and 90a in the pipe height direction Dih within the first blade air channels 81 and 81a and which controls the displacement of the first inserts 90 and 90a in a propagation direction of the cross-section of the first inserts 90 and 90a, and the second guide element 115, which enables the displacement of the second inserts 95 and 95a in the pipe height direction Dih within the second blade air channels 85 and 85a and which controls the displacement of the second inserts 95 and 95a in a propagation direction of the cross-section of the second inserts 95 and 95a.The first guide element 110 includes the first groove element 111, which has the first groove 112 extending in the pipe height direction Dih, and the first convex element 113, which enters the inside of the first groove 112 and is relatively movable in the pipe height direction Dih with respect to the first groove 112. One element of the first groove element 111 and the first convex element 113 is attached to the outer circumferential plate section 91 of the first inserts 90 and 90a, and the other element is attached to the first channel-defining surface 81p of the blade bodies 51 and 51a. The second guide element 115 includes the second groove element 116, which has the second groove 117 extending in the pipe height direction, and the second convex element 118, which enters the inside of the second groove 117 and is relatively movable in the pipe height direction Dih with respect to the second groove 117.One element of the second groove element 116 and the second convex element 118 is attached to the sealing plate section 98 of the second inserts 95 and 95a, and the other element is attached to a section that is closed at one end on the first blade height side Dh1 in the second blade air channels 85 and 85a in the blade bodies 51 and 51a.

[0152] (10) According to a tenth aspect of the stator blade, the stator blade according to any aspect of the first to ninth aspects further comprises the first sheath 60i, which is provided at one end on the first blade height side Dh1 in the blade bodies 51, 51a and 51c, the second sheath 60o, which is provided at one end on the second blade height side Dh2 in the blade bodies 51, 51a and 51c, and the baffle plate 78, which has the multiple baffle holes 79. The first casing 60i includes the casing body 61, which has the gas path surface 64 facing the second blade height side Dh2 and the counter-gas path surface 65, which faces a side opposite the gas path surface 64, and the circumferential wall 71, which is provided along the circumferential edge of the casing body 61 and projects from the counter-gas path surface 65 to the first blade height side Dh1.The baffle plate 78 is formed from the casing body 61 and the circumferential wall 71 and is attached to the first casing 60i in such a way that the cavity 72 within the concave section, which is recessed towards the second blade height side Dh2, is divided into a space on the first blade height side Dh1 and a space on the second blade height side Dh2, and the several baffle holes 79 of the baffle plate 78 extend in the blade height direction Dh.

[0153] In this scenario, the cooling air Ac flowing into the stator blade can perform the impact cooling action on the inside of the stator blade three times. Therefore, in this scenario, the stator blade can be cooled efficiently, and the amount of cooling air Ac consumed can be reduced.

[0154] For example, the gas turbine in the embodiment described above is to be understood as follows. (11) According to an eleventh aspect, the gas turbine is provided, comprising the stator blade according to any aspect of the first aspect up to the tenth aspect, the rotor 41, which rotates about the axis Ar, and the casing 45, which covers the outer circumferential side of the rotor 41. The stator blade is attached to the inner circumferential surface of the casing 45. Industrial applicability

[0155] According to one aspect of the present disclosure, a stator blade can be effectively cooled, and the amount of cooling air consumed can be minimized while improving durability. Reference symbol list 10 Gas turbine 11 Gas turbine rotor 15 gas turbine casings 16 intermediate housings 20 Compressor 21 Compressor rotor 22 Rotor shaft 23 rotor blade rows 23a Rotor blade 25 Compressor housings 26 stator blade row 26a Stator blade 30 combustion chamber 40 Turbine 41 Turbine rotor 42 Rotor shaft 43 rotor blade rows 43A Rotor blade 45 turbine housings 45a Outdoor housing 45b Inner housing 45c ring segment 46 stator blade row 46a Stator blade 49 Combustion gas channel 50, 50a, 50b, 50c, 50d stator blade 51, 51a, 51c Blade body 52 Leading edge 53 trailing edge 54 suction area 54f suction-side first blade surface section 54s suction-side second blade surface section 55 printing area 55f pressure-side first blade surface section 55s pressure-side second blade surface section 60° outer casing 60i inner casing 61 Sheathing bodies 62f front end surface 62b rear end surface 63n suction-side end surface 63p print-side end surface 64 Gas path surface 65 Counter-gas path surface 71 Perimeter wall 71f front circumferential wall 71b rear perimeter wall 71n suction-side perimeter wall 71p pressure-side circumferential wall 72 Cavity 76 holders 78 Impact plate 79 Impact Hole 80 Blade air duct 80f front blade air channel 80fa front ejection hole 80° opening 80b rear blade air duct 80ba rear ejection hole 80 opening 80m inter-blade air duct 81, 81a, 81c first blade air channel 81p first channel-defining area 82f First opening (or simply opening) 82s second opening 83nf suction-side first discharge hole 83pf pressure-side first ejection hole 84 Sealing flange 85, 85a, 85c second blade air channel 85p second channel-defining area 86, 86c opening 87ns suction-side second ejection hole 87p pressure-side second ejection hole 88 Sealing flange 90, 90a, 90b, 90c first use 90° insertion opening 91 Outer perimeter plate section 92 Impact Hole 93 Sealing plate section 94, 94b, 94c Flange section 95, 95a, 95b, 95c second deployment 95° insertion opening 96 Outer perimeter plate section 97 Impact Hole 98 Sealing plate section 99 Flange section 100, 100a, 100c End cover 101, 101a Cover plate section 102 Outer perimeter plate section 110 first guide element 111 first slot element 112 first groove 113 first convex element 115 second guide element 116 second slot element 117 second groove 118 second convex element A air AC cooling air Fuel G Combustion gas Ar axis CL curvature line C1 first internal blade cavity C2 second internal blade cavity Since axial direction Dau axial upstream side Dad axial downstream side DC circumferential direction DCP perimeter print page DCN peripheral suction side Dr. Radial direction Dri Radial inside Dro radial outer side Dh. shovel height direction Dh1 first shovel height side Dh2 second shovel height side The pipe height direction Dih1 Pipe height sealing side Dih2 pipe height opening side QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2021053113

[0002] JP 4885275

[0008]

Claims

[1] Stator blade provided in a gas turbine, comprising: a blade body which has a blade shape in a cross-section and extends in a blade height direction which has a directional component perpendicular to the cross-section; a first insert and a second insert, which have a tubular shape, extend in a tube-height direction and are arranged within the blade body such that the tube-height direction faces the blade-height direction; and an end cover, wherein the blade body contains several blade air channels that extend in the blade height direction within the blade body, of the multiple blade air channels, both a first blade air channel and a second blade air channel have an open end on a blade height side, which is one side of a first blade height side and a second blade height side in the blade height direction, Both the first and second deployments are included: an outer circumferential plate section that has a tubular shape and extends in the pipe height direction, and a sealing plate section that closes one end on a pipe height sealing side, which is one side of the outer circumference plate section in the pipe height direction from two sides in the pipe height direction, the outer circumferential plate section has several impact holes that penetrate from an inside to an outside of the tubular outer circumferential plate section, a pipe height opening side, which is the other side of the outer circumference plate section in the pipe height direction, is open, the outer circumferential plate section of the first insert has a gap that is present between the outer circumferential plate section of the first insert and a first channel-defining surface of the blade body, which defines the first blade air channel, and is arranged within the first blade air channel, so that cooling air flows from an opening of the first insert into the outer circumferential plate section, the outer circumferential plate section of the second insert is configured such that the pipe-height opening side of the second insert faces one blade height side, has a gap that is present between the outer circumferential plate section of the second insert and a second channel-defining surface of the blade body that defines the second blade air channel, and is arranged within the second blade air channel so that cooling air flows from an opening of the second insert, and The end cover is provided on one blade height side of the blade body, so that the cooling air ejected from the multiple impact holes of the first insert between the outer circumferential plate section of the first insert and the first channel-defining surface is directed from the opening of the second insert through the opening of the first blade air channel into the second insert, and covers the opening of the first blade air channel and the opening of the second insert. [2] Turbine stator blade according to claim 1, wherein a blade surface, which is an outer surface of the blade body, contains: a first blade surface section that has a back-to-back positional relationship with the first channel-defining surface, and a second blade surface section having a back-to-back positional relationship with the surface defining the second channel, which forms several impact holes on a section of the outer circumferential plate section facing the first blade surface section during the first use, and which forms several impact holes on a section of the outer circumferential plate section facing the second blade surface section during the second use. [3] Turbine stator blade according to claim 2, wherein the blade body has several ejection holes that penetrate from the second channel-defining surface to the second blade surface section, and a position of the second blade surface section on the blade surface is a position where a pressure of a section along the second blade surface section outside the blade body, while the gas turbine is driven, is lower than a pressure of a section along the first blade surface section outside the blade body. [4] Turbine stator blade according to claim 3, the blade body contains: a leading edge extending in the direction of the blade height, a trailing edge extending in the direction of the blade height, and a pressure surface and a suction surface extending in the blade height direction and connecting the leading edge and the trailing edge, the first blade surface section being a section of a blade surface from the pressure surface and the suction surface, and the second blade surface section being closer to one side of the trailing edge than the first blade surface section is to the one blade surface. [5] Turbine stator blade according to claim 3, the blade body contains: a leading edge extending in the direction of the blade height, a trailing edge extending in the direction of the blade height, and a pressure surface and a suction surface extending in the blade height direction and connecting the leading edge and the trailing edge, the first blade surface section being a section of the pressure surface, and the second blade surface section being a section of the suction surface. [6] Turbine stator blade according to any one of claims 1 to 5, wherein in the first blade air channel one end on the first blade height side and one end on the second blade height side of the first blade air channel are open, where one end of the second blade air channel is closed on the first blade height side of the second blade air channel and one end is open on the second blade height side, the first insert includes a flanged section extending from one end on the pipe height opening side at the outer circumferential plate section of the first insert to an outer circumferential side of the outer circumferential plate section of the first insert, extending to the first channel-defining surface and connected to the blade body, the second insert includes a flanged section extending from one end on the pipe height opening side at the outer circumferential plate section of the second insert to an outer circumferential side of the outer circumferential plate section of the second insert, extending to the second channel-defining surface and connected to the blade body, the outer circumferential plate section of the first insert is arranged within the first blade air channel such that the pipe height opening side of the first insert faces the first blade height side, and The outer circumferential plate section of the second insert is arranged within the second blade air channel such that the pipe height opening side of the second insert faces the second blade height side. [7] Turbine stator blade according to any one of claims 1 to 6, further comprising: a first guide element that allows displacement of the first insert in the pipe height direction within the first blade air channel and regulates the displacement of the first insert in a propagation direction of the cross-section of the first insert; and a second guide element that allows displacement of the second insert in the pipe height direction within the second blade air channel and regulates the displacement of the second insert in a propagation direction of the cross-section of the second insert. [8] Turbine stator blade according to claim 7, the first guide element contains: a first groove element having a first groove extending in the pipe height direction, and a first convex element that enters an inside of the first groove and is relatively movable in the pipe height direction with respect to the first groove, one element of the first groove element and the first convex element is attached to the first insert and the other element is attached to the first channel-defining surface, which contains the second guide element: a second groove element having a second groove extending in the pipe height direction, and a second convex element that enters an inside of the second groove and is relatively movable in the pipe height direction with respect to the second groove, and one element of the second groove element and the second convex element is attached to the second insert and the other element is attached to the second channel-defining surface. [9] Stator blade according to claim 6, further comprising: a first guide element that allows displacement of the first insert in the pipe height direction within the first blade air channel and regulates the displacement of the first insert in a propagation direction of the cross-section of the first insert; and a second guide element that allows displacement of the second insert in the pipe height direction within the second blade air channel and regulates displacement of the second insert in a propagation direction of the cross-section of the second insert, the first guide element contains: a first groove element having a first groove extending in the pipe height direction, and a first convex element that enters an inside of the first groove and is relatively movable in the pipe height direction with respect to the first groove, one element of the first groove element and the first convex element is attached to the outer circumferential plate section of the first insert, and the other element is attached to the first channel-defining surface of the blade body, the second guide element contains: a second groove element having a second groove extending in the pipe height direction, and a second convex element that enters an inside of the second groove and is relatively movable in the pipe height direction with respect to the second groove, and one element of the second groove element and the second convex element is attached to the sealing plate section of the second insert, and the other element is attached to a section that is closed at one end on the first blade height side in the second blade air channel in the blade body. [10] Turbine stator blade according to any one of claims 1 to 9, further comprising: a first sheathing which is provided at one end on the first blade height side in the blade body; a second casing, which is provided at one end on the second side of the blade height in the blade body, and a baffle plate that has several impact holes, the first sheath contains: a casing body having a gas path surface facing the second blade height side and a counter-gas path surface facing a side opposite the gas path surface, and a circumferential wall provided along a circumferential edge of the casing body and projecting from the counter-gas path surface to the first blade height side, and The baffle plate is formed from the casing body and the circumferential wall and is attached to the first casing in such a way that a cavity within a concave section, which is recessed towards the second blade height side, is divided into a space on the first blade height side and a space on the second blade height side, and the multiple baffle holes of the baffle plate extend in the blade height direction. [11] Gas turbine, comprising: Turbine stator blade according to one of claims 1 to 10, a rotor that rotates around an axis; and a housing that covers one outer circumferential side of the rotor, the stator blade is attached to an inner circumferential surface of the housing.