Gas turbine stator blade and gas turbine

Abstract

A gas turbine stationary blade according to the present invention comprises: a path that passes through the inside of a blade shape part so as to connect an outer cavity, which is formed on the outer side of an outer shroud in the blade height direction, and an inner cavity, which is formed on the inner side of an inner shroud in the blade height direction; a sealed tube that is provided in the path and that is configured to guide the air in the outer cavity to the inner cavity; a fixed plate that is attached to the sealed tube and that is fixed to the outer shroud; and a heat-shielding plate that is disposed on the outer side of the fixed plate in the blade height direction and that is disposed to cover at least a portion of the outer shroud, wherein when A is defined as the projected area obtained by projection of the outer shroud onto a plane orthogonal to the blade height direction and B is defined as the projected area obtained by projection of the heat-shielding plate onto a plane orthogonal to the blade height direction, B / A ≥ 0.40 is satisfied.

Description

Technical Field

[0001] The present disclosure relates to a gas turbine stator vane and a gas turbine. This application claims priority based on Japanese Patent Application No. 2022-114636 filed with the Japan Patent Office on July 19, 2022, and incorporates its content herein by reference.

Background Art

[0002] In the gas turbine described in Patent Document 1, an outer cavity is formed between the gas turbine stator vane and the turbine casing, and the cooling air guided to the outer cavity passes through a tube disposed in a passage formed inside the gas turbine stator vane and is guided to the inner circumferential side (the inner side in the radial direction of the gas turbine) of the gas turbine stator vane, and it is described that it is used for cooling the rotor shaft on the inner circumferential side of the gas turbine stator vane. In this configuration, since the cooling air is guided to the inner circumferential side of the gas turbine through the tube disposed in the internal passage of the gas turbine stator vane, the tube suppresses the temperature of the cooling air from rising due to convective heat transfer and heat input by radiation from the wall surface of the internal passage of the gas turbine stator vane, and it is possible to suppress a decrease in the cooling capacity of the cooling air.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, the gas turbine stator vane includes an outer shroud connected to the outside of the airfoil in the blade height direction and an inner shroud connected to the inside of the airfoil in the blade height direction. When the temperature of the cooling air in the outer cavity facing the outer shroud during the operation of the gas turbine rises due to the heat input from the outer shroud, the cooling capacity of the cooling air decreases. Further, when the temperature of the cooling air in the inner cavity facing the inner shroud during the operation of the gas turbine rises due to the heat input from the inner shroud, the cooling capacity of the cooling air decreases. In this regard, Patent Document 1 does not disclose any findings regarding such problems and their solutions.

[0005] In view of the above circumstances, at least one embodiment of the present disclosure aims to provide a gas turbine stator vane and a gas turbine capable of suppressing an increase in the temperature of cooling air.

Means for Solving the Problems

[0006] To achieve the above object, a gas turbine stator vane according to at least one embodiment of the present disclosure is a gas turbine stator vane comprising an airfoil portion, an outer shroud connected to the outside of the airfoil portion in the blade height direction, an inner shroud connected to the inside of the airfoil portion in the blade height direction, a passage passing through the inside of the airfoil portion so as to communicate an outer cavity formed outside the outer shroud in the blade height direction and an inner cavity formed inside the inner shroud in the blade height direction, a seal tube disposed in the passage and configured to guide the air in the outer cavity to the inner cavity, a fixing plate attached to the seal tube and fixed to the outer shroud, a heat shield plate disposed outside the fixing plate in the blade height direction and arranged to cover at least a part of the outer shroud, and comprising Let the projected area of the outer shroud projected onto a plane perpendicular to the blade height direction be A, and the projected area of the heat shield projected onto a plane perpendicular to the blade height direction be B. It satisfies B / A≧0.40.

[0007] To achieve the above object, the gas turbine stator vane according to at least one embodiment of the present disclosure is an airfoil portion, an outer shroud connected to the outer end of the airfoil portion in the blade height direction, an inner shroud connected to the inner end of the airfoil portion in the blade height direction, a passage passing through the inside of the airfoil portion so as to communicate an outer cavity formed outside the outer shroud in the blade height direction and an inner cavity formed inside the inner shroud in the blade height direction, a seal tube disposed in the passage and configured to guide the air in the outer cavity to the inner cavity, a fixing plate attached to the seal tube and fixed to the inner shroud, a heat shield disposed inside the fixing plate in the blade height direction and disposed so as to cover at least a part of the inner shroud, and includes.

[0008] To achieve the above object, the gas turbine according to at least one embodiment of the present disclosure is the above gas turbine stator vane, a turbine rotor, a turbine casing that houses the turbine rotor, and includes.

Advantages of the Invention

[0009] According to at least one embodiment of the present disclosure, a gas turbine stator vane and a gas turbine capable of suppressing an increase in the temperature of cooling air are provided.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Best Mode for Carrying Out the Invention

[0011] Hereinafter, some embodiments of the present disclosure will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described as embodiments or shown in the drawings are not intended to limit the scope of the invention thereto, but are merely illustrative examples. For example, expressions representing relative or absolute arrangements such as "in a certain direction", "along a certain direction", "parallel", "orthogonal", "center", "concentric", or "coaxial" not only strictly represent such arrangements, but also represent states in which there are tolerances or relative displacements with angles or distances that can obtain the same function. For example, expressions representing that things such as "identical", "equal", and "homogeneous" are in an equal state not only strictly represent an equal state, but also represent states in which there are tolerances or differences that can obtain the same function. For example, expressions representing shapes such as a rectangular shape or a cylindrical shape not only represent shapes such as a rectangular shape or a cylindrical shape in a geometrically strict sense, but also represent shapes including concave and convex portions, chamfered portions, etc. within a range where the same effect can be obtained. On the other hand, the expressions "comprising", "having", "including", or "possessing" a component are not exclusive expressions that exclude the existence of other components.

[0012] FIG. 1 is a diagram showing a schematic configuration of a gas turbine 2 according to an embodiment. As shown in FIG. 1, the gas turbine 2 includes a compressor 4, a combustor 6 for mixing and burning the compressed air generated by the compressor 4 with fuel, and a turbine 8 for obtaining power from the combustion gas generated by the combustor 6.

[0013] As shown in FIG. 1, the turbine 8 includes a rotor 9 (turbine rotor), a turbine casing 10 that houses the rotor 9, a plurality of turbine stator blades 12 (gas turbine stator blades) fixed to the inner surface of the turbine casing 10, and a plurality of turbine rotor blades 16 implanted in the rotor 9 so as to be alternately arranged in the axial direction with respect to the turbine stator blades 12. Hereinafter, unless otherwise specified, the "circumferential direction" means the circumferential direction of the gas turbine 2, that is, the circumferential direction of the rotor 9, the "axial direction" means the axial direction of the gas turbine 2, that is, the axial direction of the rotor 9, and the "radial direction" means the radial direction of the gas turbine 2, that is, the radial direction of the rotor 9, unless otherwise specified.

[0014] FIG. 2 is a diagram showing an example of a cross section along the blade height direction in the turbine stator blade 12. As shown in FIG. 2, the turbine stator blade 12 includes an airfoil portion 20, an outer shroud 22, an inner shroud 24, a passage 25, a seal tube 26, a fixing plate 28, and a heat shield plate 30. In this specification, the "blade height direction" means the blade height direction of the turbine stator blade 12, that is, the blade height direction of the airfoil portion 20, and means the radial direction of the gas turbine 2.

[0015] The airfoil portion 20 has an airfoil cross-sectional shape defined by a pressure surface and a suction surface. Inside the airfoil portion 20, a passage 25 is formed that communicates an outer cavity 32 formed outside the outer shroud 22 in the blade height direction and an inner cavity 34 formed inside the inner shroud 24 in the blade height direction. The outer cavity 32 is a space formed between the outer shroud 22 and the turbine casing 10 (see FIG. 1), and the inner cavity 34 is a space formed between the inner shroud 24 and the inner peripheral diaphragm 27.

[0016] The outer shroud 22 is connected to the outer end 20a of the airfoil portion 20 in the blade height direction and is formed in a substantially plate shape along a plane intersecting the blade height direction. The outer shroud 22 forms the outer peripheral wall 33 of the combustion gas flow path 31 (the main flow path of the combustion gas in the turbine 8) in the turbine 8. The upstream end face 50 in the axial direction of the outer shroud 22 is formed with a hook 51 protruding toward the upstream side in the axial direction, and the downstream end face 52 in the axial direction of the outer shroud 22 is formed with a hook 53 protruding toward the downstream side in the axial direction. The turbine stator vane 12 is fixed to the turbine casing 10 by engaging the hooks 51 and 53 with grooves (not shown) formed on the inner surface of the turbine casing 10, respectively. In this specification, "upstream side in the axial direction" means the upstream side of the main flow of the combustion gas in the turbine 8 in the axial direction (the flow of the combustion gas flowing through the flow path 31), and "downstream side in the axial direction" means the downstream side of the main flow of the combustion gas in the turbine 8 in the axial direction (the flow of the combustion gas flowing through the flow path 31).

[0017] The inner shroud 24 is connected to the inner end 20b of the airfoil portion 20 in the blade height direction and is formed in a substantially plate shape along a plane intersecting the blade height direction. The inner shroud 24 forms the inner peripheral wall 35 of the combustion gas flow path 31 (the main flow path of the combustion gas in the turbine 8) in the turbine 8. The annular inner peripheral diaphragm 27 disposed on the inner peripheral side of the inner shroud 24 is fixed to the inner shroud 24.

[0018] The passage 25 passes through the inside of the airfoil portion 20 and communicates the outer cavity 32 formed outside the outer shroud 22 in the blade height direction with the inner cavity 34 formed inside the inner shroud 24 in the blade height direction. The inlet 36 of the passage 25 is formed on the outer wall surface 38 in the blade height direction of the outer shroud 22, and the outlet 40 of the passage 25 is formed on the inner wall surface 42 in the blade height direction of the inner shroud 24.

[0019] The seal tube 26 is configured in a tubular shape and is disposed in the passage 25 along the extending direction of the passage 25 (the axial direction of the passage 25). The seal tube 26 is configured to guide the air in the outer cavity 32 to the inner cavity 34 inside the inner shroud 24 in the blade height direction.

[0020] Compressed air from the compressor 4 is supplied as cooling air to the outer cavity 32. The cooling air flowing from the outer cavity 32 into the seal tube 26 passes through the holes 55 formed in the inner cavity 34 and the inner peripheral diaphragm 27 and is supplied to the inter-stage space 56 (disk cavity) between the turbine stator blade 12 and the turbine rotor blade 16 (see FIG. 1) adjacent to the upstream side of the turbine stator blade 12 and functions as cooling air.

[0021] FIG. 3 is an enlarged view of the outer end portion in the blade height direction of the turbine stator blade 12 shown in FIG. 2. As shown in FIG. 3, the fixing plate 28 is attached to and fixed to the outer peripheral surface 44 of the outer end portion 43 in the blade height direction of the seal tube 26. The seal tube 26 is provided so as to penetrate through the through hole 45 formed in the central portion of the fixing plate 28, and the outer peripheral surface 44 of the seal tube 26 and the inner surface 46 of the through hole 45 are joined by, for example, welding. The fixing plate 28 is disposed on and fixed to the outer wall surface 38 in the blade height direction of the outer shroud 22 so as to block the outer portion of the seal tube 26 in the inlet 36 of the passage 25.

[0022] The heat shield 30 is disposed outside the fixed plate 28 in the blade height direction. The heat shield 30 is disposed with a gap from the fixed plate 28 in the blade height direction. In the illustrated example, the heat shield 30 is disposed parallel to each of the wall surface 38 and the fixed plate 28 with a gap from each of the fixed plate 28 and the wall surface 38 in the blade height direction. The heat shield 30 includes a plate-like top plate portion 60 and a side wall portion 62. The top plate portion 60 is connected to the peripheral edge 61 of the top plate portion 60 and is provided so as to surround the seal tube 26 and the fixed plate 28. A gap g1 is provided between the heat shield 30 and the seal tube 26. In the illustrated example, a through hole 64 through which the seal tube 26 penetrates is formed in the heat shield 30, and a gap g1 is provided over the entire circumference of the seal tube 26 between the inner surface 65 of the through hole 64 and the outer peripheral surface 44 of the seal tube 26. The heat shield 30 is not formed with an impingement cooling hole for impingement-cooling the wall surface 38 of the outer shroud 22. The outer end 26a of the seal tube 26 in the blade height direction is preferably located outside the heat shield 30 in the blade height direction from the viewpoint of suppressing the temperature rise of the cooling air taken into the seal tube 26, but the outer end 26a of the seal tube 26 may be at the same position as the heat shield 30 or inside the heat shield 30 in the blade height direction.

[0023] In the illustrated exemplary embodiment, a gap adjustment plate 66 is disposed on the heat shield 30, and a through hole 67 through which the seal tube 26 penetrates is formed in the gap adjustment plate 66. A gap g2 is provided over the entire circumference of the seal tube 26 between the inner surface 68 of the through hole 67 and the outer peripheral surface 44 of the seal tube 26. At each position on the outer peripheral surface 44 of the seal tube 26, the gap g2 is smaller than the gap g1.

[0024] FIG. 4 is a view of the turbine stator vane 12 viewed along the blade height direction from the outside in the blade height direction. In the example shown in FIG. 4, a pair of circumferentially adjacent turbine stator vanes 12 share one outer shroud 22. That is, the airfoil portions 20 of a pair of circumferentially adjacent turbine stator vanes 12 are connected to one outer shroud 22.

[0025] As shown in at least one of FIGS. 3 and 4, the outer shroud 22 includes a bottom plate portion 70 connected to the outer end 20a of the airfoil 20 in the airfoil height direction, and a flange-shaped peripheral wall portion 72 formed along the peripheral edge 71 of the bottom plate portion 70 and protruding outward from the peripheral edge 71 in the airfoil height direction. The bottom plate portion 70 is disposed facing the flow path 31 (see FIG. 2) of the combustion gas in the turbine 8, and forms the outer peripheral wall 33 of the flow path 31 (the main flow path of the combustion gas in the turbine 8) in the turbine 8. The peripheral wall portion 72 includes an upstream peripheral wall portion 72a extending in the circumferential direction along the upstream edge V1 in the axial direction of the peripheral edge 71 of the bottom plate portion 70, a downstream peripheral wall portion 72b extending in the circumferential direction along the downstream edge V2 in the axial direction of the peripheral edge 71 of the bottom plate portion 70, a one-side peripheral wall portion 72c extending in a direction intersecting the circumferential direction along the edge V3 on one side (pressure surface side) in the circumferential direction of the peripheral edge 71 of the bottom plate portion 70, and a the other-side peripheral wall portion 72d extending in a direction intersecting the circumferential direction along the edge V4 on the other side (negative pressure surface side) in the circumferential direction of the peripheral edge 71 of the bottom plate portion 70. The aforementioned hook 51 is provided so as to protrude axially upstream from the axially upstream end face 50 of the upstream peripheral wall portion 72a, and the hook 53 is provided so as to protrude axially downstream from the axially downstream end face 52 of the downstream peripheral wall portion 72b.

[0026] In the exemplary form shown in FIG. 4, the cross-sectional shape perpendicular to the airfoil height direction in each of the passage 25, the seal tube 26, and the through hole 67 has an airfoil shape, and the cross-sectional shape perpendicular to the airfoil height direction in each of the fixing plate 28 and the through hole 45 has a rounded rectangle (oval shape). In the view in the airfoil height direction, the peripheral edge 28a of the fixing plate 28 is located outside the passage 25, and the inner surface 45a of the through hole 45 of the fixing plate 28 is located inside the peripheral edge 66a of the gap adjusting plate 66 and outside the through hole 67 of the gap adjusting plate 66.

[0027] FIG. 5 is a diagram for explaining the dimensional relationship of each part in FIG. 4. In the exemplary form shown in FIG. 5, the dimension L1 of the heat shield 30 in the axial direction is larger than the dimension C of the inlet 36 of the passage 25 in the axial direction. Further, the dimension L1 of the heat shield 30 in the axial direction is larger than the dimension L2 of the fixed plate 28 in the axial direction. Also, the distance d1 between the heat shield 30 and the upstream end 51a of the outer shroud 22 in the axial direction is smaller than the distance d2 between the inlet 36 of the passage 25 and the upstream end 51a of the outer shroud 22 in the axial direction, and the distance d3 between the heat shield 30 and the downstream end 53a of the outer shroud 22 in the axial direction is smaller than the distance d4 between the inlet 36 and the downstream end 53a of the outer shroud 22 in the axial direction. Further, the distance d1 between the heat shield 30 and the upstream end 51a of the outer shroud 22 in the axial direction is smaller than the distance d5 between the fixed plate 28 and the upstream end 51a of the outer shroud 22 in the axial direction, and the distance d3 between the heat shield 30 and the downstream end 53a of the outer shroud 22 in the axial direction is smaller than the distance d6 between the fixed plate 28 and the downstream end 53a of the outer shroud 22 in the axial direction.

[0028] Here, for the turbine stator blade 12 described with reference to FIGS. 2 to 5, if the projected area (the projected area corresponding to the hatched portion in FIG. 6) obtained by projecting the outer shroud 22 onto a plane orthogonal to the blade height direction is A, and the projected area (the projected area corresponding to the hatched portion in FIG. 7) obtained by projecting the heat shield 30 onto a plane orthogonal to the blade height direction is B, then B / A ≧ 0.40 is satisfied. The value obtained by dividing B by A may be 0.40 or more, preferably 0.45 or more, and more preferably 0.50 or more.

[0029] Hereinafter, the effects exhibited by the turbine stator blade 12 will be described. According to the turbine stator blade 12, the cooling air in the outer cavity 32 is guided to the inner cavity 34 through the inside of the seal tube 26 disposed in the passage 25 passing through the inside of the airfoil portion 20. For this reason, the seal tube 26 suppresses the temperature of the cooling air passing through the inside of the seal tube 26 from rising due to convective heat transfer and radiation from the wall surface of the passage 25 inside the airfoil portion 20, and it is possible to suppress a decrease in the cooling ability of the cooling air.

[0030] Further, a heat shield plate 30 disposed outside the fixed plate 28 in the blade height direction covers at least a part of the outer shroud 22. When the projected area of the outer shroud 22 projected onto a plane orthogonal to the blade height direction is A, and the projected area of the heat shield plate 30 projected onto a plane orthogonal to the blade height direction is B, B / A≧0.40 is satisfied. Therefore, the heat shield plate 30 effectively suppresses the cooling air in the outer cavity 32 from rising due to the heat input from the outer shroud 22, and can suppress the temperature rise of the cooling air supplied to the turbine stator vane 12. As a result, compared with the configuration without the heat shield plate 30, the required cooling effect can be obtained with a smaller amount of cooling air, or a higher cooling effect can be obtained with the same amount of cooling air.

[0031] Further, according to the turbine stator vane 12 described above, since the space surrounded by the heat shield plate 30 and the outer shroud 22 communicates with the outer cavity 32 through the gap g1 provided between the heat shield plate 30 and the seal tube 26, it is possible to suppress the occurrence of a pressure difference on both surfaces of the heat shield plate 30 and suppress the detachment of the heat shield plate 30.

[0032] In some embodiments, for example, as shown in FIG. 5, when the axial dimension of the inlet 36 of the passage 25 is C, the number of turbine stator vanes 12 connected to one outer shroud 22 is N, and the circumferential dimension of the outer shroud 22 is D, B≧C×D / N may be satisfied. That is, B may be equal to or greater than the value obtained by multiplying C by D and dividing by N. In the illustrated example, N is 2. Therefore, the heat shield plate 30 effectively suppresses the cooling air in the outer cavity 32 from rising due to the heat input from the outer shroud 22, and can suppress the temperature rise of the cooling air supplied to the turbine stator vane 12.

[0033] In some embodiments, when the projected area (the projected area corresponding to the hatched portion in FIG. 7) of the heat shield 30 projected onto a plane orthogonal to the blade height direction is B, and the projected area (the projected area corresponding to the hatched portion in FIG. 8) of the portion 57 (see FIG. 8) surrounded by the frame-shaped peripheral wall portion 72 in the bottom plate portion 70 projected onto a plane orthogonal to the blade height direction is E, B / E ≧ 0.50 is satisfied. The value obtained by dividing B by E may be 0.50 or more, preferably 0.55 or more, and more preferably 0.60 or more.

[0034] Among the bottom plate portion 70, the portion 57 surrounded by the peripheral wall portion 72 has a thin wall and is the most heat-conductive, so it has a great influence on the amount of heat input from the outer shroud 22 to the cooling air in the outer cavity 32. For this reason, it is effective to install the heat shield 30 in this portion. By satisfying B / E ≧ 0.50 as described above, the heat shield 30 can effectively suppress the cooling air in the outer cavity 32 from rising due to heat input from the outer shroud 22, and can suppress the temperature rise of the cooling air supplied to the turbine stator vane 12.

[0035] In some embodiments, when the projected area (the projected area corresponding to the hatched portion in FIG. 7) of the heat shield 30 projected onto a plane orthogonal to the blade height direction is B, and the projected area (the area corresponding to the hatched portion in FIG. 9) of the portion 58 (see FIG. 9. In the illustrated example, the portion composed of the frame-shaped peripheral wall portion 72 and the bottom plate portion 70) excluding the hooks 51, 53 in the outer shroud 22 projected onto a plane orthogonal to the blade height direction is F, B / F ≧ 0.45 is satisfied. The value obtained by dividing B by F may be 0.45 or more, preferably 0.50 or more, and more preferably 0.55 or more.

[0036] Among the outer shroud 22, the hooks 51, 53 for fixing the outer shroud 22 to the turbine casing 10 have little influence on the amount of heat input from the outer shroud 22 to the cooling air in the outer cavity 32. For this reason, by satisfying B / F ≧ 0.45 as described above, the heat shield 30 can effectively suppress the cooling air in the outer cavity 32 from rising due to heat input from the outer shroud 22, and can suppress the temperature rise of the cooling air supplied to the turbine stator vane 12.

[0037] In some embodiments, as shown in FIG. 10 for example, among the peripheral edge 59 of the heat shield 30, if the upstream edge in the axial direction is K1, the downstream edge in the axial direction is K2, one edge in the circumferential direction is K3, and the other edge in the circumferential direction is K4, the turbine stator blade 12 may include a welded portion W1 where the heat shield 30 and the surface 38 of the outer shroud 22 are welded along the edge K1, a welded portion W2 where the heat shield 30 and the surface 38 of the outer shroud 22 are welded along the edge K2, a welded portion W3 where the heat shield 30 and the surface 38 of the outer shroud 22 are welded along the edge K3, and a welded portion W4 where the heat shield 30 and the surface 38 of the outer shroud 22 are welded along the edge K4. In the illustrated example, in the welded portion W1, the heat shield 30 and the surface 38 of the outer shroud 22 are welded at a plurality of locations with intervals along the edge K1, in the welded portion W2, the heat shield 30 and the surface 38 of the outer shroud 22 are welded at a plurality of locations with intervals along the edge K2, in the welded portion W3, the heat shield 30 and the surface 38 of the outer shroud 22 are welded at a plurality of locations with intervals along the edge K3, and in the welded portion W4, the heat shield 30 and the surface 38 of the outer shroud 22 are welded at a plurality of locations with intervals along the edge K4.

[0038] Thus, by providing the welded portions W1, W2, W3, and W4, not only can the detachment of the heat shield 30 be suppressed, but also the cooling air in the outer cavity 32 can be suppressed from passing through the gap between the peripheral edge 59 of the heat shield 30 and the outer shroud 22, and the temperature rise of the cooling air caused by the passage can be suppressed.

[0039] In some embodiments, as shown in FIG. 11 for example, among the peripheral edge 59 of the heat shield 30, if the upstream edge in the axial direction is K1, the downstream edge in the axial direction is K2, one edge in the circumferential direction is K3, and the other edge in the circumferential direction is K4, the turbine stator blade 12 may not include a welded portion where the heat shield 30 and the surface 38 of the outer shroud 22 are welded along the edge K1, and a welded portion where the heat shield 30 and the surface 38 of the outer shroud 22 are welded along the edge K2. In the example shown in FIG. 10, the turbine stator blade 12 includes a welded portion W3 where the heat shield 30 and the surface 38 of the outer shroud 22 are welded along the edge K3, and a welded portion W4 where the heat shield 30 and the surface 38 of the outer shroud 22 are welded along the edge K4. In the illustrated example, in the welded portion W3, the heat shield 30 and the surface 38 of the outer shroud 22 are welded at a plurality of locations at intervals along the edge K3, and in the welded portion W4, the heat shield 30 and the surface 38 of the outer shroud 22 are welded at a plurality of locations at intervals along the edge K4.

[0040] Since the cooling air in the outer cavity 32 flows along the circumferential direction, as described above, by providing the welded portion W3 where the heat shield 30 and the outer shroud 22 are welded along one edge K3 in the circumferential direction among the peripheral edge 59 of the heat shield 30, and the welded portion W4 where the heat shield 30 and the outer shroud 22 are welded along the other edge K4 in the circumferential direction among the peripheral edge 59 of the heat shield 30, it is possible to suppress the cooling air in the outer cavity 32 from entering and exiting through the gap between the peripheral edge 59 of the heat shield 30 and the outer shroud 22, and to suppress the temperature rise of the cooling air caused by the entry and exit. Further, since there is no welded portion where the heat shield 30 and the outer shroud 22 are welded along the upstream edge K1 in the axial direction among the peripheral edge 59 of the heat shield 30, and no welded portion where the heat shield 30 and the outer shroud 22 are welded along the downstream edge K2 in the axial direction among the peripheral edge 59 of the heat shield 30, it is possible to suppress the temperature rise of the cooling air caused by the above entry and exit while reducing the labor and cost of welding.

[0041] FIG. 12 is a view showing a modified example of the turbine stator vane 12 shown in FIG. 2, and is a view showing another example of a cross section along the blade height direction in the turbine stator vane 12. In the turbine stator vane 12 described below, components having the same reference numerals as those of the turbine stator vane 12 shown in FIG. 2 represent components having the same configurations as those of the turbine stator vane 12 shown in FIG. 2 unless otherwise specified, and the description thereof will be omitted.

[0042] In the exemplary embodiment shown in FIG. 12, the turbine stator vane 12 includes a fixing plate 74 and a heat shield plate 76 fixed to the inner shroud 24. The turbine stator vane 12 also includes a cylindrical insert 48 inserted into the passage 25. The insert 48 includes impingement cooling holes (not shown) that penetrate the inner peripheral surface and the outer peripheral surface of the insert 48, and a gap is provided between the outer peripheral surface of the insert 48 and the inner surface (the wall surface of the passage 25) of the airfoil portion 20.

[0043] In the exemplary embodiment shown in FIG. 12, the seal tube 26 is disposed along the extending direction (the axial direction of the passage 25) of the passage 25 inside the insert 48 in the passage 25. The seal tube 26 is configured to guide the air in the outer cavity 32 to the inner cavity 34 inside the inner shroud 24 in the blade height direction.

[0044] Compressed air from the compressor 4 is supplied as cooling air to the outer cavity 32. The cooling air flowing from the outer cavity 32 into the seal tube 26 passes through the holes 55 formed in the inner cavity 34 and the inner peripheral side diaphragm 27 and is supplied to the interstage space 56 (disk cavity) between the turbine stator vane 12 and the turbine rotor vane 16 (see FIG. 1) adjacent to the upstream side of the turbine stator vane 12 to function as cooling air. In addition, the cooling air flowing from the outer cavity 32 into the inside of the insert 48 is injected from the impingement cooling holes (not shown) formed in the insert 48 onto the inner surface of the airfoil portion 20, and then flows out from the film cooling holes (not shown) formed in the airfoil portion 20 to the outer surface side of the airfoil portion 20.

[0045] FIG. 13 is an enlarged view of the inner end portion in the blade height direction of the turbine stator vane 12 shown in FIG. 12. As shown in FIG. 13, the fixed plate 74 is attached to and fixed to the outer peripheral surface 78 of the inner end 77 in the blade height direction of the seal tube 26. The seal tube 26 is provided so as to penetrate through a through hole 79 formed in the central portion of the fixed plate 74, and the outer peripheral surface 78 of the seal tube 26 and the inner surface of the through hole 79 are joined by, for example, welding or the like. The fixed plate 74 is disposed on and fixed to the inner wall surface 80 in the blade height direction of the inner shroud 24 so as to block the outer portion of the outlet 40 of the passage 25 outside the seal tube 26.

[0046] The heat shield plate 76 is disposed inside the fixed plate 74 in the blade height direction (inside the fixed plate 74 in the radial direction). The heat shield plate 76 is disposed with a gap in the blade height direction so as to cover at least a part of the fixed plate 74. In the illustrated example, the heat shield plate 76 is disposed parallel to each of the wall surface 80 and the fixed plate 74 with a gap between each of the fixed plate 74 and the wall surface 80 in the blade height direction. A through hole 82 through which the seal tube 26 penetrates is formed in the heat shield plate 76, and a gap g3 is provided over the entire circumference of the seal tube 26 between the inner surface of the through hole 82 and the outer peripheral surface 78 of the seal tube 26. In the illustrated exemplary embodiment, a step is formed in the blade height direction between the wall surface 80 to which the fixed plate 74 is fixed and the wall surface 81 to which the heat shield plate 76 is fixed in the inner shroud 24, and the wall surface 81 is located inside the wall surface 81 in the blade height direction.

[0047] Note that the heat shield plate 76 is not formed with impingement cooling holes for impingement cooling the wall surface 80 of the inner shroud 24. Also, in the illustrated configuration, the inner end 26b of the seal tube 26 in the blade height direction is located inside the heat shield plate 76 in the blade height direction, but the inner end 26b of the seal tube 26 may be at the same position as the heat shield plate 76 or outside the heat shield plate 76 in the blade height direction.

[0048] In the illustrated exemplary embodiment, a gap adjusting plate 83 is disposed on the heat shield plate 76, and a through hole 84 through which the seal tube 26 penetrates is formed in the gap adjusting plate 83. A gap g4 is provided over the entire circumference of the seal tube 26 between the inner surface of the through hole 84 and the outer peripheral surface 28 of the seal tube 26. At each position on the outer peripheral surface 44 of the seal tube 26, the gap g4 between the gap adjusting plate 83 and the outer peripheral surface 44 of the seal tube 26 is smaller than the gap g3 between the heat shield plate 76 and the outer peripheral surface 44 of the seal tube 26.

[0049] FIG. 14 is a view for explaining the configuration of the inner end portion in the blade height direction of the turbine stator blade 12 shown in FIG. 13. As shown in FIG. 14, the dimension L3 of the heat shield plate 76 in the axial direction is larger than the dimension E of the outlet 40 of the passage 25 in the axial direction. Further, the dimension L3 of the heat shield plate 76 in the axial direction is larger than the dimension L4 of the fixing plate 28 in the axial direction. Also, the distance d7 between the heat shield plate 76 and the upstream end 85a of the inner shroud 24 in the axial direction is smaller than the distance d8 between the outlet 40 of the passage 25 and the upstream end 85a of the inner shroud 24 in the axial direction, and the distance d9 between the heat shield plate 76 and the downstream end 85b of the inner shroud 24 in the axial direction is smaller than the distance d10 between the outlet 40 and the downstream end 85b of the inner shroud 24 in the axial direction. Further, the distance d7 between the heat shield plate 76 and the upstream end 85a of the inner shroud 24 in the axial direction is smaller than the distance d11 between the fixing plate 74 and the upstream end 85a of the inner shroud 24 in the axial direction, and the distance d9 between the heat shield plate 76 and the downstream end 85b of the inner shroud 24 in the axial direction is smaller than the distance d12 between the fixing plate 74 and the downstream end 85b of the inner shroud 24 in the axial direction.

[0050] Hereinafter, the effects of the turbine stator blade 12 described with reference to FIGS. 12 to 14 will be described. According to the above-described turbine stator vane 12, the cooling air in the outer cavity 32 is guided to the inner cavity 34 through the inside of a seal tube 26 disposed in a passage 25 passing through the inside of the airfoil portion 20. Therefore, the seal tube 26 suppresses the temperature of the cooling air passing through the inside of the seal tube 26 from rising due to convective heat transfer and radiation from the wall surface of the passage 25 inside the airfoil portion 20 and the inner surface of the insert 48, and it is possible to suppress a decrease in the cooling capacity of the cooling air. Further, the fixing plate 74 can suppress air that has been used for cooling the airfoil portion 20 from leaking into the inner peripheral cavity 34 through the gap between the outer surface of the insert 48 and the inner surface of the airfoil portion 20.

[0051] Further, since a heat shield plate 76 disposed inside the fixing plate 74 in the blade height direction (inside the fixing plate 74 in the radial direction) covers at least a part of the inner shroud 24, the heat shield plate 76 effectively suppresses the cooling air in the inner cavity 34 from rising due to heat input from the inner shroud 24, and it is possible to suppress a temperature rise of the cooling air supplied to the above-described inter-paragraph space 56 (disk cavity). Thereby, compared with a configuration in which the heat shield plate 76 is not provided, it is possible to obtain a required cooling effect with a smaller amount of cooling air, or it is possible to obtain a high cooling effect with the same amount of cooling air.

[0052] Also, according to the above-described turbine stator vane 12, since the space surrounded by the heat shield plate 76, the inner shroud 24, and the fixing plate 74 communicates with the inner cavity 34 through a gap g3 provided between the heat shield plate 76 and the seal tube 26, it is possible to suppress a pressure difference from occurring between both surfaces of the heat shield plate 76 and to suppress the heat shield plate 76 from falling off.

[0053] The present disclosure is not limited to the above-described embodiments, and includes forms obtained by modifying the above-described embodiments and forms obtained by appropriately combining these forms.

[0054] The content described in each of the above embodiments is understood as follows, for example.

[0055] (1) The gas turbine stator vane (e.g., the turbine stator vane 12 described above) according to at least one embodiment of the present disclosure includes an airfoil (e.g., the airfoil 20 described above), an outer shroud (e.g., the outer shroud 22 described above) connected to an outer end (e.g., the outer end 20a described above) of the airfoil in the blade height direction, an inner shroud (e.g., the inner shroud 24 described above) connected to an inner end (e.g., the inner end 20b described above) of the airfoil in the blade height direction, a passage (e.g., the passage 25 described above) passing through the interior of the airfoil so as to communicate an outer cavity (e.g., the outer cavity 32 described above) formed outside the outer shroud in the blade height direction and an inner cavity (e.g., the inner cavity 34 described above) formed inside the inner shroud in the blade height direction, a seal tube (e.g., the seal tube 26 described above) disposed in the passage and configured to guide air in the outer cavity to the inner cavity, a fixing plate (e.g., the fixing plate 28 described above) attached to the seal tube and fixed to the outer shroud, a heat shield plate (e.g., the heat shield plate 30 described above) disposed outside the fixing plate in the blade height direction and arranged to cover at least a part of the outer shroud, and when an area of a projection of the outer shroud on a plane orthogonal to the blade height direction is A and an area of a projection of the heat shield plate on a plane orthogonal to the blade height direction is B, B / A ≧ 0.40 is satisfied.

[0056] According to the gas turbine stationary vane described in the above (1), since the cooling air in the outer cavity is guided to the inner cavity through the inside of the seal tube arranged in the passage passing through the inside of the airfoil portion, the seal tube suppresses the temperature of the cooling air passing through the inside of the seal tube from rising due to convective heat transfer and radiation from the wall surface of the passage inside the airfoil portion, and it is possible to suppress a decrease in the cooling capacity of the cooling air. Further, a heat shield plate arranged outside the fixing plate in the blade height direction covers at least a part of the outer shroud. When the projected area of the outer shroud projected onto a plane orthogonal to the blade height direction is A and the projected area of the heat shield plate projected onto a plane orthogonal to the blade height direction is B, B / A ≥ 0.40 is satisfied. For this reason, the heat shield plate effectively suppresses the cooling air in the outer cavity from rising due to heat input from the outer shroud, and it is possible to suppress a temperature rise of the cooling air supplied to the gas turbine stationary vane.

[0057] (2) In some embodiments, in the gas turbine stationary vane described in the above (1), When the dimension of the inlet of the passage in the axial direction of the gas turbine is C, the number of gas turbine stationary vanes connected to the outer shroud is N, and the dimension of the outer shroud in the circumferential direction of the gas turbine is D, B ≥ C × D / N is satisfied.

[0058] According to the gas turbine stationary vane described in the above (2), the heat shield plate effectively suppresses the cooling air in the outer cavity from rising due to heat input from the outer shroud, and it is possible to suppress a temperature rise of the cooling air supplied to the gas turbine stationary vane.

[0059] (3) In some embodiments, in the gas turbine stationary vane described in the above (1) or (2), The outer shroud is a bottom plate portion (for example, the bottom plate portion 70 described above) connected to the outer end of the airfoil portion in the blade height direction, and a peripheral wall portion (for example, the peripheral wall portion 72 described above) formed along the periphery of the bottom plate portion (for example, the periphery 71 described above) and protruding outward in the blade height direction from the periphery. including the heat shield is provided to cover at least a part of the portion (for example, the above-mentioned portion 57) surrounded by the peripheral wall portion in the bottom plate portion, assuming that the projected area obtained by projecting the portion surrounded by the peripheral wall portion in the bottom plate portion onto a plane orthogonal to the blade height direction is E, B / E ≥ 0.50 is satisfied.

[0060] Among the bottom plate portions, the portion surrounded by the peripheral wall portion has a thin wall and is the most prone to heat transfer. Therefore, it has a great influence on the amount of heat input from the outer shroud to the cooling air in the outer cavity. For this reason, it is effective to install a heat shield on the portion of the bottom plate portion surrounded by the peripheral wall portion. By satisfying B / E ≥ 0.50 as described in (3) above, the heat shield can effectively suppress the rise in the cooling air in the outer cavity due to heat input from the outer shroud, and suppress the temperature rise of the cooling air supplied to the gas turbine stator blade.

[0061] (4) In some embodiments, in the gas turbine stator blade according to any one of (1) to (3) above, assuming that the projected area obtained by projecting the portion (for example, the above-mentioned portion 58) of the outer shroud excluding the hooks (for example, the above-mentioned hooks 51, 53) for fixing the outer shroud to the turbine casing onto a plane orthogonal to the blade height direction is F, B / F ≥ 0.45 is satisfied.

[0062] The hooks for fixing the outer shroud to the turbine casing in the outer shroud have little influence on the amount of heat input from the outer shroud to the cooling air in the outer cavity. For this reason, as described in (4) above, by satisfying B / F ≥ 0.45, the heat shield can effectively suppress the rise in the cooling air in the outer cavity due to heat input from the outer shroud, and suppress the temperature rise of the cooling air supplied to the gas turbine stator blade.

[0063] (5) In some embodiments, in the gas turbine stator blade according to any one of (1) to (4) above, The dimension of the heat shield in the axial direction of the gas turbine (for example, the dimension L1 described above) is larger than the dimension of the inlet of the passage in the axial direction (for example, the dimension C described above).

[0064] According to the gas turbine stationary blade described in (5) above, the heat shield can effectively suppress the rise of the cooling air in the outer cavity due to the heat input from the outer shroud, and can suppress the temperature rise of the cooling air supplied to the gas turbine stationary blade.

[0065] (6) In some embodiments, in the gas turbine stationary blade according to any one of (1) to (5) above, The dimension of the heat shield in the axial direction of the gas turbine (for example, the dimension L1 described above) is larger than the dimension of the fixing plate in the axial direction (for example, the dimension L2 described above).

[0066] According to the gas turbine stationary blade described in (6) above, the heat shield can effectively suppress the rise of the cooling air in the outer cavity due to the heat input from the outer shroud, and can suppress the temperature rise of the cooling air supplied to the gas turbine stationary blade.

[0067] (7) In some embodiments, in the gas turbine stationary blade according to any one of (1) to (6) above, The distance between the heat shield and the upstream end of the outer shroud in the axial direction of the gas turbine (for example, the distance d1 described above) is smaller than the distance between the inlet of the passage and the upstream end of the outer shroud in the axial direction (for example, the distance d2 described above), and the distance between the heat shield and the downstream end of the outer shroud in the axial direction (for example, the distance d3 described above) is smaller than the distance between the inlet and the downstream end of the outer shroud in the axial direction (for example, the distance d4 described above).

[0068] According to the gas turbine stationary blade described in (7) above, the heat shield can effectively suppress the rise of the cooling air in the outer cavity due to the heat input from the outer shroud, and can suppress the temperature rise of the cooling air supplied to the gas turbine stationary blade.

[0069] (8) In some embodiments, in the gas turbine stator vane described in any one of (1) to (7) above, For the heat shield, the distance between the heat shield and the upstream end of the outer shroud in the axial direction of the gas turbine (for example, the distance d1 described above) is smaller than the distance between the fixing plate and the upstream end of the outer shroud in the axial direction (for example, the distance d5 described above), and the distance between the heat shield and the downstream end of the outer shroud in the axial direction (for example, the distance d3 described above) is smaller than the distance between the fixing plate and the downstream end of the outer shroud in the axial direction (for example, the distance d6 described above).

[0070] According to the gas turbine stator vane described in (8) above, the heat shield effectively suppresses the rise of the cooling air in the outer cavity due to the heat input from the outer shroud, and can suppress the temperature rise of the cooling air supplied to the gas turbine stator vane.

[0071] (9) In some embodiments, in the gas turbine stator vane described in any one of (1) to (8) above, A gap (for example, the gap g1 described above) is provided between the heat shield and the seal tube.

[0072] According to the gas turbine stator vane described in (9) above, the space surrounded by the heat shield and the outer shroud and the outer cavity communicate with each other through the gap provided between the heat shield and the seal tube, so that the pressure difference on both sides of the heat shield is suppressed, and the dropping off of the heat shield can be suppressed.

[0073] (10) In some embodiments, in the gas turbine stator vane described in any one of (1) to (9) above, The heat shield is not formed with impingement cooling holes for impingement cooling of the outer shroud.

[0074] According to the gas turbine stator vane described in the above (10), the heat insulation plate effectively suppresses the rise of the cooling air in the outer cavity due to the heat input from the outer shroud, and can suppress the temperature rise of the cooling air supplied to the gas turbine stator vane.

[0075] (11) In some embodiments, in the gas turbine stator vane described in any one of the above (1) to (10), A welded portion (for example, the welded portion W1 described above) where the heat insulation plate and the outer shroud are welded along the upstream edge (for example, the edge K1 described above) in the axial direction of the gas turbine among the peripheral edges (for example, the peripheral edge 59 described above) of the heat insulation plate, A welded portion (for example, the welded portion W2 described above) where the heat insulation plate and the outer shroud are welded along the downstream edge (for example, the edge K2 described above) in the axial direction among the peripheral edges of the heat insulation plate, A welded portion (for example, the welded portion W3 described above) where the heat insulation plate and the outer shroud are welded along one edge (for example, the edge K3 described above) in the circumferential direction of the gas turbine among the peripheral edges of the heat insulation plate, A welded portion (for example, the welded portion W4 described above) where the heat insulation plate and the outer shroud are welded along the other edge (for example, the edge K4 described above) in the circumferential direction among the peripheral edges of the heat insulation plate, are further provided.

[0076] According to the gas turbine stator vane described in the above (11), by providing each of the above welded portions, not only can the detachment of the heat insulation plate be suppressed, but also the cooling air in the outer cavity can be suppressed from entering and exiting the gap between the heat insulation plate and the outer shroud through the space between the peripheral edge of the heat insulation plate and the outer shroud, and the temperature rise of the cooling air caused by the entry and exit can be suppressed.

[0077] (12) In some embodiments, in the gas turbine stator vane described in any one of the above (1) to (10), A welded portion (e.g., the above-described welded portion W1) where the heat shield and the outer shroud are welded along an upstream edge (e.g., the above-described edge K1) in the axial direction of the gas turbine among the peripheral edges (e.g., the above-described peripheral edge 59) of the heat shield, A welded portion (e.g., the above-described welded portion W2) where the heat shield and the outer shroud are welded along a downstream edge (e.g., the above-described edge K2) in the axial direction among the peripheral edges of the heat shield, is not provided, A welded portion (e.g., the above-described welded portion W3) where the heat shield and the outer shroud are welded along one edge (e.g., the above-described edge K3) in the circumferential direction of the gas turbine among the peripheral edges of the heat shield, A welded portion (e.g., the above-described welded portion W4) where the heat shield and the outer shroud are welded along the other edge (e.g., the above-described edge K4) in the circumferential direction among the peripheral edges of the heat shield, is further provided.

[0078] Since the cooling air in the outer cavity flows along the circumferential direction, as described in the above (12), by providing a welded portion where the heat shield and the outer shroud are welded along one edge in the circumferential direction among the peripheral edges of the heat shield, and a welded portion where the heat shield and the outer shroud are welded along the other edge in the circumferential direction among the peripheral edges of the heat shield, it is possible to suppress the cooling air in the outer cavity from entering and exiting through the gap between the heat shield and the outer shroud, and to suppress the temperature rise of the cooling air caused by the entry and exit. Further, since there is no welded portion where the heat shield and the outer shroud are welded along the upstream edge in the axial direction of the gas turbine among the peripheral edges of the heat shield and a welded portion where the heat shield and the outer shroud are welded along the downstream edge in the axial direction among the peripheral edges of the heat shield, it is possible to suppress the temperature rise of the cooling air caused by the above entry and exit while reducing the labor and cost of welding.

[0079] (13) The gas turbine stator vane (e.g., the above-described turbine stator vane 12) according to at least one embodiment of the present disclosure, an airfoil portion (e.g., the above-described airfoil portion 20), An outer shroud (such as the outer shroud 22 described above) connected to the outer end of the airfoil portion (such as the outer end 20a described above) in the wing height direction, An inner shroud (such as the inner shroud 24 described above) connected to the inner end of the airfoil portion (such as the inner end 20b described above) in the wing height direction, A passage (such as the passage 25 described above) passing through the inside of the airfoil portion so as to communicate the outer cavity (such as the outer cavity 32 described above) formed outside the outer shroud in the wing height direction and the inner cavity (such as the inner cavity 34 described above) formed inside the inner shroud in the wing height direction, A seal tube (such as the seal tube 26 described above) disposed in the passage and configured to guide the air in the outer cavity to the inner cavity, A fixing plate (such as the fixing plate 74 described above) attached to the seal tube and fixed to the inner shroud, A heat shield plate (such as the heat shield plate 76 described above) disposed inside the fixing plate in the wing height direction and disposed to cover at least a part of the inner shroud, and comprising.

[0080] According to the gas turbine stator vane described in the above (13), the cooling air in the outer cavity is guided to the inner cavity through the inside of a seal tube disposed in a passage passing through the inside of the airfoil portion. Therefore, the seal tube suppresses the temperature of the cooling air passing through the inside of the seal tube from rising due to convective heat transfer and radiation from the wall surface of the passage inside the airfoil portion, etc., and it is possible to suppress a decrease in the cooling capacity of the cooling air. Further, since a heat shield plate disposed inside the fixing plate in the blade height direction (inside the fixing plate in the radial direction of the gas turbine) covers at least a part of the inner shroud, the heat shield plate effectively suppresses the cooling air in the inner cavity from rising due to heat input from the inner shroud, and it is possible to suppress a temperature rise of the cooling air supplied to the disk cavity. Thereby, as compared with a configuration in which no heat shield plate is provided, it is possible to obtain a required cooling effect with a smaller amount of cooling air, or it is possible to obtain a high cooling effect with the same amount of cooling air.

[0081] (14) In some embodiments, in the gas turbine stator vane described in the above (13), The dimension of the heat shield plate in the axial direction of the gas turbine (for example, the dimension L3 described above) is larger than the dimension of the outlet of the passage in the axial direction (for example, the dimension E described above).

[0082] According to the gas turbine stator vane described in the above (14), the heat shield plate effectively suppresses the cooling air in the inner cavity from rising due to heat input from the inner shroud, and it is possible to suppress a temperature rise of the cooling air supplied to the gas turbine stator vane.

[0083] (15) In some embodiments, in the gas turbine stator vane described in the above (13) or (14), The dimension of the heat shield plate in the axial direction of the gas turbine (for example, the dimension L3 described above) is larger than the dimension of the fixing plate in the axial direction (for example, the dimension L4 described above).

[0084] According to the gas turbine stator vane described in the above (15), the heat shield plate effectively suppresses the rise of the cooling air in the inner cavity due to the heat input from the inner shroud, and can suppress the temperature rise of the cooling air supplied to the gas turbine stator vane.

[0085] (16) In some embodiments, in the gas turbine stator vane described in any one of the above (13) to (15), The distance (for example, the distance d7 described above) between the heat shield plate and the upstream end of the inner shroud in the axial direction of the gas turbine is smaller than the distance (for example, the distance d8 described above) between the outlet of the passage and the upstream end of the inner shroud in the axial direction, and the distance (for example, the distance d9 described above) between the heat shield plate and the downstream end of the inner shroud in the axial direction is smaller than the distance (for example, the distance d10 described above) between the outlet and the downstream end of the inner shroud in the axial direction.

[0086] According to the gas turbine stator vane described in the above (16), the heat shield plate effectively suppresses the rise of the cooling air in the inner cavity due to the heat input from the inner shroud, and can suppress the temperature rise of the cooling air supplied to the gas turbine stator vane.

[0087] (17) In some embodiments, in the gas turbine stator vane described in any one of the above (13) to (16), The distance (for example, the distance d7 described above) between the heat shield plate and the upstream end of the inner shroud in the axial direction of the gas turbine is smaller than the distance (for example, the distance d11 described above) between the fixing plate and the upstream end of the inner shroud in the axial direction, and the distance (for example, the distance d9 described above) between the heat shield plate and the downstream end of the inner shroud in the axial direction is smaller than the distance (for example, the distance d12 described above) between the fixing plate and the downstream end of the inner shroud in the axial direction.

[0088] (18) In some embodiments, in the gas turbine stator vane described in any one of the above (13) to (17), A gap (for example, the above-described gap g3) is provided between the heat shield and the seal tube.

[0089] According to the gas turbine stator vane described in the above (18), since the space surrounded by the heat shield and the inner shroud communicates with the inner cavity through the gap provided between the heat shield and the seal tube, a pressure difference is suppressed from occurring on both sides of the heat shield, and the detachment of the heat shield can be suppressed.

[0090] (19) A gas turbine according to at least one embodiment of the present disclosure includes the gas turbine stator vane according to any one of the above (1) to (18), a turbine rotor, a turbine casing that houses the turbine rotor, and is provided with.

[0091] According to the gas turbine described in the above (19), since it includes the gas turbine stator vane according to any one of the above (1) to (18), the heat shield effectively suppresses the rise in the temperature of the cooling air supplied to the gas turbine stator vane by the heat input from the outer shroud or the inner shroud, and the rise in the temperature of the cooling air can be suppressed.

Explanation of Reference Numerals

[0092] 2 Gas turbine 4 Compressor 6 Combustor 8 Turbine 9 Rotor (turbine rotor) 10 Turbine casing 12 Turbine stator vane 16 Turbine rotor blade 20 Airfoil portion 20a Outer end 20b Inner end 22 Outer shroud 24 Inner shroud 25 Passage 26 Seal tube 26a Outer end 26b Inner end 27 Inner peripheral diaphragm 28, 74 Fixed plate 28a, 59, 61, 66a, 71 Periphery 30, 6 Heat shield 31 Flow path 32 Outer cavity 33 Outer peripheral wall 34 Inner cavity 35 Inner peripheral wall 36 Inlet 38, 42, 80, 81 Wall surface 40 Outlet 43, 77 End 44, 78 Outer peripheral surface 45, 64, 67, 79, 82, 84 Through hole 45a, 46, 65, 68 Inner surface 50, 52 End face 51, 53 Hook 51a, 85a Upstream end 53a, 85b Downstream end 55 Hole 56 Inter-paragraph space 57, 58 Portion 60 Top plate part 62 Side wall part 66, 83 Gap adjustment plate 70 Bottom plate part 72 Peripheral wall part 72a, 72b Upstream side peripheral wall part 72b Downstream side peripheral wall part 72c One-side peripheral wall part 72d The other-side peripheral wall part A, B, E, F Projection area C, D Dimension K1, K2, K3, K4, V1, V2, V3, V4 Edge W1, W2, W3, W4 Weld part d1, d2, d3, d4, d5, d6, d7, d8, d9, d10, d11, d12 Distance g1, g2, g3, g4 Gap

Claims

1. A gas turbine stationary vane, comprising: an airfoil portion; an outer shroud connected to an outer end of the airfoil portion in the vane height direction; an inner shroud connected to an inner end of the airfoil portion in the vane height direction; a passage passing through the interior of the airfoil portion so as to communicate an outer cavity formed outside the outer shroud in the vane height direction and an inner cavity formed inside the inner shroud in the vane height direction; a seal tube disposed in the passage and configured to guide air in the outer cavity to the inner cavity; a fixing plate attached to the seal tube and fixed to the outer shroud; a heat shield disposed outside the fixing plate in the vane height direction and configured to cover at least a part of the outer shroud; wherein, when a projected area of the outer shroud projected onto a plane perpendicular to the vane height direction is A and a projected area of the heat shield projected onto a plane perpendicular to the vane height direction is B, the gas turbine stationary vane satisfies B / A≥0.

40.

2. When a dimension of an inlet of the passage in the axial direction of the gas turbine is C, a number of gas turbine stationary vanes connected to the outer shroud is N, and a dimension of the outer shroud in the circumferential direction of the gas turbine is D, the gas turbine stationary vane according to Claim 1 satisfies B≥C×D / N.

3. The outer shroud includes: a bottom plate portion connected to the outer end of the airfoil portion in the vane height direction; a peripheral wall portion formed along a periphery of the bottom plate portion and protruding outward in the vane height direction from the periphery; wherein, the heat shield is provided so as to cover at least a part of a portion surrounded by the peripheral wall portion in the bottom plate portion, and when a projected area of the portion surrounded by the peripheral wall portion in the bottom plate portion projected onto a plane perpendicular to the vane height direction is E, the gas turbine stationary vane according to Claim 1 satisfies B / E≥0.

50.

4. When a projected area of a portion of the outer shroud excluding a hook for fixing the outer shroud to a turbine casing projected onto a plane perpendicular to the vane height direction is F, the gas turbine stationary vane according to Claim 1 satisfies B / F≥0.

45.

5. In the gas turbine stationary vane according to Claim 1, a dimension of the heat shield in the axial direction of the gas turbine is larger than a dimension of an inlet of the passage in the axial direction.

6. The dimension of the heat shield plate in the axial direction of the gas turbine is larger than the dimension of the fixing plate in the axial direction, the gas turbine stationary vane according to claim 1.

7. For the heat shield plate, the distance between the heat shield plate and the upstream end of the outer shroud in the axial direction of the gas turbine is smaller than the distance between the inlet of the passage and the upstream end of the outer shroud in the axial direction, and the distance between the heat shield plate and the downstream end of the outer shroud in the axial direction is smaller than the distance between the inlet and the downstream end of the outer shroud in the axial direction, the gas turbine stationary vane according to claim 1.

8. For the heat shield plate, the distance between the heat shield plate and the upstream end of the outer shroud in the axial direction of the gas turbine is smaller than the distance between the fixing plate and the upstream end of the outer shroud in the axial direction, and the distance between the heat shield plate and the downstream end of the outer shroud in the axial direction is smaller than the distance between the fixing plate and the downstream end of the outer shroud in the axial direction, the gas turbine stationary vane according to claim 1.

9. A gap is provided between the heat shield plate and the seal tube, the gas turbine stationary vane according to claim 1.

10. The heat shield plate is not formed with impingement cooling holes for impingement cooling of the outer shroud, the gas turbine stationary vane according to claim 1.

11. A welded portion where the heat shield plate and the outer shroud are welded along the upstream edge in the axial direction of the gas turbine among the peripheral edges of the heat shield plate, A welded portion where the heat shield plate and the outer shroud are welded along the downstream edge in the axial direction among the peripheral edges of the heat shield plate, A welded portion where the heat shield plate and the outer shroud are welded along one edge in the circumferential direction of the gas turbine among the peripheral edges of the heat shield plate, A welded portion where the heat shield plate and the outer shroud are welded along the other edge in the circumferential direction among the peripheral edges of the heat shield plate, The gas turbine stationary vane according to claim 1, further comprising.

12. A welded portion where the heat shield plate and the outer shroud are welded along the upstream edge in the axial direction of the gas turbine among the peripheral edges of the heat shield plate, A welded portion where the heat shield plate and the outer shroud are welded along the downstream edge in the axial direction among the peripheral edges of the heat shield plate, not provided with, A welded portion where the heat shield and the outer shroud are welded along one edge of the periphery of the heat shield in the circumferential direction of the gas turbine, A welded portion where the heat shield and the outer shroud are welded along the other edge of the periphery of the heat shield in the circumferential direction, further comprising, The gas turbine stator blade according to claim 1.

13. A gas turbine stator blade, An airfoil portion, An outer shroud connected to the outer end of the airfoil portion in the blade height direction, An inner shroud connected to the inner end of the airfoil portion in the blade height direction, A passage passing through the inside of the airfoil portion so as to communicate an outer cavity formed outside the outer shroud in the blade height direction and an inner cavity formed inside the inner shroud in the blade height direction, A seal tube disposed in the passage and configured to guide the air in the outer cavity to the inner cavity, A fixing plate attached to the seal tube and fixed to the inner shroud, A heat shield disposed inside the fixing plate in the blade height direction and arranged to cover at least a part of the inner shroud, comprising a gas turbine stator blade.

14. The gas turbine stator blade according to claim 13, wherein the dimension of the heat shield in the axial direction of the gas turbine is larger than the dimension of the outlet of the passage in the axial direction.

15. The gas turbine stator blade according to claim 13, wherein the dimension of the heat shield in the axial direction of the gas turbine is larger than the dimension of the fixing plate in the axial direction.

16. The distance between the heat shield and the upstream end of the inner shroud in the axial direction of the gas turbine is smaller than the distance between the outlet of the passage and the upstream end of the inner shroud in the axial direction, and the distance between the heat shield and the downstream end of the inner shroud in the axial direction is smaller than the distance between the outlet and the downstream end of the inner shroud in the axial direction. The gas turbine stator blade according to claim 13.

17. In the gas turbine, in the axial direction, the distance between the heat shield and the upstream end of the inner shroud is smaller than the distance between the fixed plate and the upstream end of the inner shroud in the axial direction, and the distance between the heat shield and the downstream end of the inner shroud in the axial direction is smaller than the distance between the fixed plate and the downstream end of the inner shroud in the axial direction. The gas turbine stator blade according to claim 13.

18. The gas turbine stator blade according to claim 13, wherein a gap is provided between the heat shield and the seal tube.

19. The gas turbine stator blade according to any one of claims 1 to 18, a turbine rotor, a turbine casing that houses the turbine rotor, A gas turbine comprising:

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