Cooling method and cooling structure for gas turbine vanes

Abstract

Provided is a method for cooling a turbine stationary blade. A turbine comprises: an airfoil; and an outer shroud and an inner shroud that are provided on a radial outer edge of the airfoil. The airfoil comprises a plurality of air channels that extend along a radial direction of the turbine. The plurality of air channels include a first air channel and a second air channel. Cooling air flows in the first air channel to cool the first air channel and then cools either one of the outer shroud and the inner shroud. Cooling air flows in the second air channel to cool the second air channel and then cools the other of the outer shroud and the inner shroud.

Description

[Technical Field]

[0001] The present disclosure relates to a cooling method for a stator vane of a gas turbine, and also to a cooling structure for a stator vane of a gas turbine. [Background technology]

[0002] Gas turbine stator vanes and rotor blades are exposed to high-temperature combustion gases. Therefore, the stator vanes and rotor blades need to be cooled with cooling air. For example, Patent Document 1 describes the cooling of turbine stator vanes. FIG. 3 of Patent Document 1 illustrates that the cooling gas RG first flows into the outer shroud 12, then flows downstream within the blade body 11, is injected through multiple openings 223 to cool the blade body 11, and then flows toward and into the inner shroud 13 to cool the inner shroud 13. That is, FIG. 3 of Patent Document 1 illustrates that the outer shroud 12 is first cooled, then the blade body 11 is cooled using the cooling gas RG that cooled the outer shroud 12, and then the inner shroud 13 is cooled using the cooling gas RG that cooled the blade body 11. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-019348 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, gas turbine inlet temperatures have increased, and therefore, there is a demand for further cooling of the first-stage stator vanes. One approach to addressing this issue is to supply cooling air at higher pressure and lower temperature (compared to conventional techniques) to the first-stage stator vanes. The inventors have found that if higher-pressure, lower-temperature cooling air is used to cool the first-stage stator vanes, it may be possible to reuse the cooling air to cool other components of the first-stage stator vanes, even after it has been used to cool the airfoil or shroud end. However, conventional techniques have limited the efficiency of cooling air utilization.

[0005] It is desirable to provide a cooling method or structure for gas turbine stator vanes that can increase the efficiency of cooling air usage. [Means for solving the problem]

[0006] According to a first aspect of the present disclosure, there is provided a method for cooling a turbine vane, the turbine comprising: an airfoil; and a shroud provided at an end of the airfoil along a radial direction of the turbine, the shroud including an outer shroud provided at an outer end of the airfoil along the radial direction of the turbine and an inner shroud provided at an inner end of the airfoil along the radial direction of the turbine, the airfoil having a plurality of air channels extending along the radial direction of the turbine, the plurality of air channels including a first air channel and a second air channel, Stationary blade cooling The method is: cooling air is flowed into the first air channel to cool the first air channel, and the cooling air flowing through the first air channel is used to cool one of the outer shroud and the inner shroud, cooling air is flowed into the second air channel to cool the second air channel, and the cooling air flowing through the second air channel is used to cool the other of the outer shroud and the inner shroud, the first air channel is a leading end air channel located at an upstream end of the airfoil along a flow direction of hot gas within the turbine, and the second air channel is an air channel located downstream of the leading end air channel, and the outer shroud is cooled using the cooling air flowing through the first air channel, and the inner shroud is cooled using the cooling air flowing through the second air channel.

[0007] The above-described features allow the cooling air used to cool the airfoil to be used to cool other components of the stator vane, such as the outer shroud or the inner shroud, without being discharged into the hot gas path. This improves the efficiency of cooling air use. Furthermore, the outer shroud and the inner shroud can be cooled using the cooling air, which has a relatively low temperature immediately after cooling the airfoil. Furthermore, the cooling air used to cool the first air channel can be used to cool one of the outer shroud or the inner shroud, and the cooling air used to cool an air channel different from the first air channel can be used to cool the other of the outer shroud or the inner shroud. This improves the efficiency of cooling air use.

[0008] According to a second aspect of the present disclosure, there is provided a turbine vane, the turbine vane including an airfoil, a shroud provided at an end of the airfoil along a radial direction of the turbine, and 、 Equipped with , the above The shroud includes an outer shroud provided at an outer end of the airfoil in the radial direction of the turbine, and an inner shroud provided at an inner end of the airfoil in the radial direction of the turbine. Mi, the above The airfoil includes a plurality of air channels extending along a radial direction of the turbine, the plurality of air channels including a first air channel and a second air channel. Mi, the above The airfoil includes an air intake configured to introduce cooling air from outside the vane into the first air channel and the second air channel. Well, the above The first air channel is in communication with one of the outer shroud and the inner shroud so that cooling air introduced into the first air channel flows toward the one of the outer shroud and the inner shroud to cool the one of the outer shroud and the inner shroud. and the aboveThe second air channel communicates with the other of the outer shroud and the inner shroud such that cooling air introduced into the second air channel flows toward the other of the outer shroud and the inner shroud to cool the other of the outer shroud and the inner shroud. the first air channel is a leading end air channel located at an upstream end of the airfoil along a flow direction of hot gas inside the turbine, the second air channel is an air channel located downstream of the leading end air channel, the first air channel is in communication with the outer shroud so that the outer shroud is cooled using cooling air that has flowed through the first air channel, and the second air channel is in communication with the inner shroud so that the inner shroud is cooled using cooling air that has flowed through the second air channel.

[0009] The above-described features allow the cooling air used to cool the airfoil to be used to cool other components of the stator vane, such as the outer shroud or the inner shroud, without being discharged into the hot gas path. This improves the efficiency of cooling air use. Furthermore, the cooling air can be introduced into the air channel to first cool the airfoil, and the relatively low-temperature cooling air immediately after cooling the airfoil can be used to cool the outer shroud and the inner shroud. Furthermore, the cooling air used to cool the first air channel can be used to cool one of the outer shroud or the inner shroud, and the cooling air used to cool an air channel different from the first air channel can be used to cool the other of the outer shroud or the inner shroud. This improves the efficiency of cooling air use. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic cross-sectional view of a gas turbine according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a perspective view of the stator blade in the first embodiment. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is a partially enlarged view of the stationary blade. [Figure 5] FIG. 5 is a partial perspective view of the stator blade according to the first embodiment. [Figure 6] FIG. 6 is a partial perspective view of a stator blade according to another embodiment. [Figure 7] FIG. 7 is a flowchart illustrating the method for cooling the stationary blade according to the first embodiment. [Figure 8] FIG. 8 is a flowchart illustrating a method for cooling a stationary blade according to the second embodiment. [Figure 9] FIG. 9 is a diagram for explaining the cooling step of the second embodiment. [Figure 10] FIG. 10 is a flowchart illustrating a method for cooling a stator blade according to the third embodiment. [Figure 11] FIG. 11 is a schematic cross-sectional view of a stator blade according to the fourth embodiment. [Figure 12A] FIG. 12A is a schematic cross-sectional view of a stator blade according to a fifth embodiment. [Figure 12B] FIG. 12B is a schematic cross-sectional view of the stator blade according to the fifth embodiment. [Figure 13A] FIG. 13A is a schematic cross-sectional view of a stator blade according to a sixth embodiment. [Figure 13B] FIG. 13B is a schematic cross-sectional view of the stator blade according to the sixth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Embodiments of the present disclosure will be described in detail below with reference to the drawings. Fig. 1 is a schematic cross-sectional view of a gas turbine according to an embodiment of the present disclosure. As shown in Fig. 1, a gas turbine 10 according to this embodiment includes a turbine 20 driven by combustion gas generated by a combustor 30. The turbine 20 includes a rotor shaft 24, a turbine rotor 26 that rotates about an axis Ar, a turbine casing 22 that covers the turbine rotor 26, and multiple stages of stator vanes 28.

[0012] FIG. 2 schematically illustrates a stator vane of a gas turbine according to an embodiment of the present disclosure. FIG. 2 is a perspective view of the stator vane according to a first embodiment. FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2. FIG. 4 is a partially enlarged view of the stator vane. As shown in FIG. 2, the stator vane 50 includes a stator vane body (airfoil) 51 extending in the radial direction of the gas turbine, an inner shroud 60 disposed radially inside the stator vane body 51, and an outer shroud 70 disposed radially outside the stator vane body 51. The stator vane body 51 is disposed in a combustion gas flow path (high-temperature gas flow path) through which combustion gas passes. In general, the annular combustion gas flow path is defined radially inside by the inner shroud 60 and radially outside by the outer shroud 70. The inner shroud 60 and the outer shroud 70 are plate-shaped members that define part of the combustion gas flow path.

[0013] 2, the upstream end of the stator vane body 51 has a leading edge 52, and the downstream end of the stator vane body 51 has a trailing edge 53. Of the surfaces of the stator vane body 51, the convex surface is the suction side surface 54 (suction surface), and the concave surface is the pressure side surface 55 (pressure surface). For convenience, in the following description, the pressure side (pressure surface side) of the stator vane body 51 and the pressure side (suction surface side) of the stator vane body 51 will be referred to as the pressure side and the pressure side, respectively.

[0014] The inner shroud 60 and the outer shroud 70 have basically the same structure, and therefore, the outer shroud 70 will be mainly described below.

[0015] 2 and 3, the outer shroud 70 is a plate-shaped shroud member and includes a shroud body 72, a shroud end portion 74 disposed on the outer periphery of the shroud body 72, and a peripheral wall 76 extending along the shroud end portion 74. The peripheral wall 76 protrudes from the shroud body 72 toward the radially outer side of the gas turbine.

[0016] The outer shroud 70 has a forward end face that is an upstream end face, an aft end face that is a downstream end face, a ventral end face that is a downstream end face, and a ventral end face that is a downstream end face. The outer shroud 70 has a gas path surface 78 that faces radially inward and faces the hot gas flow path. The forward end face and the aft end face are substantially parallel to each other, and the ventral end face and the suction end face are substantially parallel to each other. Therefore, when viewed radially, the outer shroud 70 has a substantially parallelogram shape, as shown in FIG. 3 .

[0017] The shroud end 74 is a flange-like or edge-like structure that protrudes from the shroud body 72. The shroud end 74 is a forward shroud end 74 located upstream of the outer shroud 70. L and an aft shroud end 74 located downstream of the outer shroud 70. T and a rear shroud end 74 disposed on the rear side of the outer shroud 70. N and a ventral shroud end 74 disposed on the ventral side of the outer shroud 70. P For example, as shown in FIG. 3, the front shroud end 74 L、 aft shroud end 74 T、 Dorsal shroud end 74 N , and the ventral shroud end 74 P is disposed on the outer periphery of the shroud body 72 and surrounds the entire shroud body 72.

[0018] Forward shroud end 74 L The front shroud end flow passage 75 is formed therein. L aft shroud end 74 T The rear shroud end flow passage 75 is disposed therein. T back shroud end 74 N The rear shroud end flow passage 75 is formed therein. N ventral shroud end 74 P The inner portion of the flow passage 75 is a ventral shroud end flow passage. P Includes:

[0019] In this embodiment, the forward shroud end flow passage 75 LAt one end thereof, the rear shroud end flow passage 75 N and the other end of the flow passage 75 P The rear shroud end flow passage 75 is connected to the rear shroud end flow passage 75. T At one end thereof, the rear shroud end flow passage 75 N and the other end of the flow passage 75 P 2, 3, and 4, the front shroud end passage 75 L has a shroud end passage inlet 171. T The forward shroud end flow passage 75 has a shroud end flow passage outlet 172. L A portion of the cooling air flowing into the suction side shroud end passage 75 N and ventral shroud end flow passage 75 P and then through the aft shroud end flow passage 75 T and exits through the shroud end flow passage outlet 172. As shown in FIG. L , 75 T , 75 P , 75 N The shroud end passage includes turbulators 175. The turbulators 175 may be ribs disposed on the inner surface of the shroud end passage. To enhance cooling of the shroud end, the turbulators 175 may be disposed on a bottom surface of the passage that defines the radially inner surface of the passage. Here, the bottom surface of the passage may extend substantially parallel to the radially inner wall 81. The turbulators 175 may also be disposed on a side surface of the passage that defines the circumferential sidewall or axial wall of the passage.

[0020] In this embodiment, the shroud end channel inlet 171 is connected to the forward shroud end channel 75 L The shroud end flow passage outlet 172 is provided at the aft shroud end flow passage 75 T However, the structure of the stator vane is not limited to this embodiment. The shroud end flow passage inlet 171 is provided in the suction side shroud end flow passage 75. N , ventral shroud end flow passage 75 P, or aft shroud end flow passage 75 T The shroud end flow passage outlet 172 may be provided in other shroud end flow passages such as the suction side shroud end flow passage 75. N , ventral shroud end flow passage 75 P , or forward shroud end flow passage 75 L Alternatively, multiple shroud end channel inlets 171 may be provided in one or more shroud end channels 75. L , 75 T , 75 N、 75 P Also, multiple shroud end flow passage outlets 172 may be provided in one or more shroud end flow passages 75. L、 75 T , 75 N , 75 P It may also be provided in.

[0021] The shroud body 72 includes a radially inner wall 81 and a radially outer wall 82 located on the opposite side thereof. The shroud body 72 includes a space S between the radially inner wall 81 and the radially outer wall 82. The radially inner surface of the inner wall 81 forms the gas path surface 78 of the outer shroud 70. This radially inner wall 81 forms a part of the shroud body 72. This radially inner wall 81 may be continuously extended in the circumferential direction or the axial direction of the gas turbine so as to form a part of the shroud end 74. FIG. 2 shows, as an example, a configuration in which the radially inner wall 81 continuously extends in the axial direction of the gas turbine to form the aft shroud end 74. T The shroud body 72 includes an impingement plate 73 that divides the space S of the outer shroud 70 into an outer region on the radially outer side and an inner region (cavity) on the radially inner side. In the outer region, a part of the cooling air flows through the aft shroud end flow passage 75. T The inner region is defined between the radially inner wall 81 of the outer shroud 70 and the impingement plate 73.

[0022] In the impingement plate 73, a plurality of impingement cooling holes 79 are provided so as to penetrate the impingement plate 73 in the radial direction. A portion of the cooling air present in the outer region flows into the inner region through the impingement cooling holes 79 of the impingement plate 73. This cooling air is injected toward the radially outer surface of the radially inner wall 81, impingement cools the radially outer surface of the radially inner wall 81, and then passes through the outer wall 82 to be discharged to the outside. For example, the cooling air injected from the impingement cooling holes 79 toward the radially outer surface of the radially inner wall 81 in order to impingement cool the radially outer surface of the radially inner wall 81 is discharged through a passage that connects the inner region of the space S to an outer space located on the opposite side (outside) of the outer wall 82 from the space S. Such a passage may be isolated from the outer region of the space S. More specifically, in the present embodiment, the cooling air is discharged through a hole in the discharge pipe 83. An exhaust pipe 83 is provided to pass through the radially outer wall 82 and the impingement plate 73 in a manner connecting the inner region with the exterior space.

[0023] <Stator blade body> The vane body 51 includes a plurality of air channels 141, 142, 143. More specifically, the interior of the vane body 51 is defined by a radially extending bulkhead 51. P The inner air channel 141 is partitioned into a plurality of air channels 141, 142, 143 by a plurality of inserts 151, 152, 153 which are inserted into the respective air channels 141, 142, 143. The plurality of inserts 151, 152, 153 include radially extending inner air channels 161, 162, 163, respectively, which extend radially from the outer shroud 70 through the stator vane body 51 toward the inner shroud 60. Each of the inserts 151, 152, 153 is formed continuously from the outer shroud 70 through the stator vane body 51 to the inner shroud 60. Each of the inner air channels 161, 162, 163 has an air intake 58 which opens to the inside of the intake manifold 56.

[0024] Each insert 151, 152, 153 has a plurality of holes (through-holes) 59 communicating with the inner air channels 161, 162, 163, respectively. A portion of the cooling air supplied to the inner air channels 161, 162, 163 of the inserts 151, 152, 153 is injected from the plurality of holes 59 toward the inner surface of the vane body 51 to impingement-cool the inner surface of the airfoil 51. Each of the plurality of air channels 141, 142, 143 has an outer air channel defined between the insert 151, 152, 153 and the inner surface of the vane body 51. A portion of the cooling air injected through the holes 59 is guided by the outer air channel and flows through the outer air channel radially outward, radially inward, or radially outward and inward. As an example, FIG. 3 shows the outer air channel 57 provided between the side of the insert 151 and the inner surface of the front end of the vane body 51.

[0025] The intake manifold 56 and the discharge pipe 83 are connected to a forced-air cooling system in which cooling air drawn from the inside of the combustor casing is cooled by an external cooler (not shown) and then compressed by an external compressor (not shown). The compressed air is used for cooling and then returned to the inside of the combustor casing. In the above description, an example in which an air-cooling system is applied to this embodiment has been described. However, the present vane is not limited to this embodiment. The present disclosure may be applied to other types of cooling systems. For example, the intake manifold 56 and the discharge pipe 83 may be connected to a closed-loop steam cooling system or a closed-loop air-cooling system. The compressed air used for cooling is supplied to the intake manifold and first supplied directly to the air intake 58 without passing through the shroud body 72 or the shroud end 74. That is, the cooling air is first used to cool the airfoil 51 before being used to cool the shroud body 72 or the shroud end 74.

[0026] In this embodiment, the air channel 141 is a leading end air channel located at the upstream end of the vane body 51. For example, in the insert 151, which is a leading end insert, a portion of the cooling air supplied to the inner air channel 161 through the air intake 58 is injected toward the inner surface of the leading end of the airfoil 51 through the holes 59, and then flows radially outward through the outer air channel 57. The outer air channel 57, which is the space between the inner surface of the leading end of the vane body 51 and the insert 151, is connected to the leading shroud end flow passage 75. L A portion of the cooling air injected toward the inner surface of the forward end of the airfoil 51 flows through the outer air channels 57 connected to the shroud end flow passage inlets 171 into the forward shroud end flow passage 75. L The flow passes through the shroud end flow passage inlet 171.

[0027] 5 is a partial perspective view of the stator vane according to the first embodiment. In this embodiment, air channel 142 is an intermediate air channel located downstream of leading end air channel 141 and located between leading end air channel 141 and trailing end air channel 143 (described in detail below). For example, in insert 152, which is an intermediate insert, a portion of the cooling air supplied to inner air channel 162 through air intake 58 is injected toward the inner surface of the center of airfoil 51 through hole 59, then flows radially inward through the outer air channel toward inner shroud 60, and finally flows into shroud end flow passage inlet 181 (located on the aft shroud end) of inner shroud 60, as shown in FIG. The cooling air then passes through the shroud end 65 of the inner shroud 60, cooling the shroud end 64 of the inner shroud 60, and flows into the shroud body 62 of the shroud 60 via the shroud end flowpath outlets 182 of the inner shroud 60 (located in the forward shroud end flowpath). Similar to the outer shroud 70, the cooling air is injected through impingement cooling holes in the impingement plate 63 to cool the radially outer wall of the inner shroud 60, with the gas path surface facing radially outward and facing the hot gas path.

[0028] In this embodiment, a portion of the cooling air injected from the leading end inner air channel 161 toward the inner surface of the leading end of the airfoil 51 flows radially outward through the outer air channel 57 toward the outer shroud 70. Also, a portion of the cooling air injected from the intermediate inner air channel 162 toward the inner surface of the central portion of the airfoil 51 flows radially inward through the outer air channel 57 toward the inner shroud 60. However, the structure of the stator vane is not limited to this embodiment. A portion of the cooling air injected from the leading end inner air channel 161 toward the inner surface of the leading end of the airfoil 51 may be configured to flow radially inward through the outer air channel 57 toward the inner shroud 60. Also, a portion of the cooling air injected from the intermediate inner air channel 162 toward the inner surface of the central portion of the airfoil 51 may be configured to flow radially outward through the outer air channel 57 toward the outer shroud 70. Such modifications will be described in detail below as other embodiments.

[0029] 2 , the air channel 143 is an aft-end air channel located at the downstream end of the vane body 51. The aft-end air channel 143 includes an airfoil cooling structure 154 downstream of the insert 153. The airfoil cooling structure 154 includes a passage with a plurality of pin fins 164 disposed therein. For example, in the aft-end insert 153, a portion of the cooling air supplied to the inner air channel (the aft-end inner air channel) 163 via the air intake 58 is injected onto the inner surface of the aft end of the airfoil 51 through the holes 59 and then directed to the airfoil cooling structure 154. The cooling air passes through the passage with the pin fins 164 and is then discharged into the hot gas path at the trailing edge 53 of the airfoil 51.

[0030] 6 is a partial perspective view of a stator vane according to another embodiment. As shown in FIG. 6, in this embodiment, the shroud end flow passage inlet 181 of the inner shroud 60 is located at the forward shroud end 64. L The shroud end flow passage outlet 182 of the inner shroud 60 is disposed above the aft shroud end 64.T In this embodiment, the shroud end flow passage inlet 171 of the outer shroud 70 is disposed above the aft shroud end 74. T Furthermore, the shroud end flow passage outlet 172 of the outer shroud 70 is located above the forward shroud end 74. L In this embodiment, in insert 151, which is the leading end insert, a portion of the cooling air supplied to inner air channel 161 through air intake 58 is injected through holes 59 toward the inner surface of the leading end of airfoil 51, then guided radially inward through outer air channel 57 toward inner shroud 60, and then exits shroud end flow passage inlet 181 of inner shroud 60 (leading shroud end 64), as shown in FIG. L The cooling air then passes through the shroud end passages 65 of the inner shroud 60, cools the shroud ends 64 of the inner shroud 60, and exits the shroud end passage outlets 182 of the inner shroud 60 (located at the aft shroud end 64). T In this embodiment, in the insert 152, which is an intermediate insert, a portion of the cooling air supplied to the inner air channel 162 through the air intake 58 is injected toward the inner surface of the center portion of the airfoil 51 through the hole 59, and then guided radially outward toward the outer shroud 70 through the outer air channel 57, and then flows into the shroud body 62 of the inner shroud 60 through the shroud end flow passage inlet 171 (located at the aft shroud end 74) of the outer shroud 70. T The cooling air then passes through the shroud end passages 75 of the outer shroud 70, cools the shroud ends 74 of the outer shroud 70, and exits the shroud end passage outlets 172 of the outer shroud 70 (located at the forward shroud end 74). L ) into the shroud body 72 of the outer shroud 70.

[0031] <Cooling method> Next, a cooling method for the stator vane according to the first embodiment will be described. FIG. 7 is a flowchart illustrating the cooling method for the stator vane according to the first embodiment. As shown in FIG. 7, in step S102, part of the cooling air flows into the leading end air channel 141 to cool the leading end air channel 141. The cooling air passes through the holes 59 of the insert 151 and is injected from the leading end inner air channel 161 toward the inner surface of the leading end of the airfoil 51, and then passes through the outer air channel 57 and is guided radially outward or radially inward toward either the outer shroud 70 or the inner shroud 60, thereby cooling the outer shroud 70 or the inner shroud 60.

[0032] In step S104, a portion of the cooling air flows into the intermediate air channel 142 to cool the intermediate air channel 142. The cooling air passes through the holes 59 in the insert 151, is injected from the intermediate inner air channel 162 toward the inner surface of the center of the airfoil 51, and is then guided radially outward or radially inward through the outer air channel 57 toward the other of the outer shroud 70 or the inner shroud 60, thereby cooling the other of the outer shroud 70 or the inner shroud 60.

[0033] Next, a cooling method for a stator vane according to a second embodiment will be described. FIG. 8 is a flowchart illustrating the cooling method for a stator vane according to the second embodiment. This method is described using the air channel 141 and the outer shroud 70 as an example. FIG. 9 schematically illustrates the cooling process of the second embodiment. As shown in FIGS. 8 and 9(a), in step S202, a portion of the cooling air flows through the air intake 58 into the inner air channel 161 of the insert 151. The cooling air is then injected through the holes 59 toward the inner surface of the leading end of the airfoil 51 to cool the airfoil 51, and flows radially outward through the outer air channel 57. In some embodiments, the cooling air flowing into the inner air channel may be introduced from a forced-air cooling system.

[0034] 9(b), in step S204, cooling air flows into the shroud end passage 75 through the shroud end passage inlet 171. The cooling air flows along the shroud end passage 75 and cools the shroud end 74.

[0035] As shown in FIG. 9(c), in step S206, cooling air flows into the outer region of the shroud body 72 and is injected through the impingement cooling holes 79 toward the radially outer surface of the radially inner wall 81, thereby impingement cooling the radially outer surface of the radially inner wall 81 and cooling the shroud body 72.

[0036] Next, a cooling method for a stator vane according to a third embodiment will be described. FIG. 10 is a flowchart illustrating the cooling method for a stator vane according to the third embodiment. As shown in FIG. 10, in step S302, in at least one air channel, a portion of the cooling air flows through an air intake into an inner air channel of the insert. The cooling air is then injected through holes toward the inner surface of the leading end of the airfoil to cool the airfoil, and flows radially outward through the outer air channel. In one embodiment, the cooling air flowing into the inner air channel may be introduced from a forced air cooling system.

[0037] In step S304, cooling air enters the outer region of the shroud body and is injected through the impingement cooling holes toward the radially outer surface of the radially inner wall to cool the radially outer surface of the radially inner wall and thereby cool the shroud body.

[0038] In step S306, cooling air flows through the shroud end channel inlets into the shroud end channel. The cooling air flows along the shroud end channel to cool the shroud end. In certain embodiments, the cooling air is returned to the forced air cooling system through the shroud end channel outlets.

[0039] Next, a fourth embodiment of the present invention will be described below. Fig. 11 is a schematic cross-sectional view of a stator vane according to the fourth embodiment. As shown in Fig. 11, in the fourth embodiment, a plurality of airfoils 51 (two in this embodiment) are arranged in a shroud end flow passage 75. L , 75 T , 75 N , 75 P Unlike the first embodiment (FIG. 3), two shroud end channel inlets 171 are provided in the forward shroud end channel 75. L It is set up in.

[0040] The outer air channels, which are the spaces between the inner surfaces of the forward ends of the two airfoils 51 and the inserts 151, are connected to the forward shroud end flow passage 75 via air passages provided at the outer ends of the outer air channels of the respective airfoils 51. L The cooling air is passed through each shroud end channel inlet 171 to the forward shroud end channel 75. L and flows into the dorsal shroud end flow passage 75 N , or ventral shroud end flow passage 75 P and flows through shroud end flow passage outlets 172 into the outer region of shroud body 72 .

[0041] In the above embodiment, the stator vane body (airfoil) includes three air channels 141, 142, and 143. However, the number of air channels included in the stator vane body (airfoil) is not limited to three. The stator vane body (airfoil) may include a different number of air channels, such as two, four, five, or more. In such an alternative embodiment, each air channel may be connected to the outer shroud or the inner shroud.

[0042] For example, a fifth embodiment of the present application will be described below. Figures 12A and 12B are schematic cross-sectional views of a stator vane according to the fifth embodiment, respectively. As shown in Figures 12A and 12B, in the fifth embodiment, a stator vane body (airfoil) includes air channels 191, 192, 193, 194, and 195 arranged in this order from the upstream end to the downstream end of the flow of hot gas in the turbine. Each of the air channels 191, 192, 193, 194, and 195 includes an insert and an inner air channel (not shown). As shown in Figure 12A, the first air channel 191 and the second air channel 192 are inserted into the forward shroud end 74. L 12B, the third air channel 193 and the fourth air channel 194 are connected to the shroud end flow passage inlet 171 of the outer shroud 70 disposed at the rear shroud end 64. T The inner shroud 60 communicates with the shroud end flow passage inlet 181 disposed at the inner shroud 60 .

[0043] In this embodiment, a portion of the cooling air introduced into the first air channel 191 flows inside the first air channel 191, is ejected from the first inner air channel through the holes 59 in the first insert toward the inner surface of the leading end of the airfoil 51, and is then directed to flow radially outward through the outer air channel 57 toward the outer shroud 70. Similarly, a portion of the cooling air ejected from the second inner air channel of the second air channel 192 through the holes 59 in the second insert toward the inner surface of the central portion of the airfoil 51 is directed to flow radially outward through its outer air channel 57 toward the outer shroud 70. The cooling air is then directed to the shroud end flow path inlets 171 of the outer shroud 70.

[0044] In this embodiment, a portion of the cooling air injected from the third inner air channel of the third air channel 193 through the holes 59 of the third insert toward the inner surface of the central portion of the airfoil 51 is directed to flow radially inward through its outer air channel 57 toward the inner shroud 60. Also, a portion of the cooling air injected from the fourth inner air channel of the fourth air channel 194 through the holes 59 of the fourth insert toward the inner surface of the central portion of the airfoil 51 is directed to flow radially inward through its outer air channel 57 toward the inner shroud 60. The cooling air is then directed to the shroud end flow path inlets 181 of the inner shroud 60.

[0045] The fifth air channel 195 is an aft end air channel located at the downstream end of the vane body 51. As previously mentioned, in the fifth air channel 195, a portion of the cooling air supplied to the fifth inner air channel through the air intake 58 is injected through the holes 59 toward the inner surface of the aft end of the airfoil 51 and then directed to flow to the airfoil cooling structure 154. A portion of the cooling air flows through passages including the pin fins 164 and is then discharged into the hot gas path at the trailing edge 53 of the airfoil 51.

[0046] The vane configuration is not limited to this embodiment. In an alternative embodiment, the shroud end flow passage inlet 171 of the outer shroud 70 is connected to the aft shroud end 74. T and the shroud end flow passage outlets 172 of the outer shroud 70 may be located at the forward shroud end 74. L The shroud end flow passage inlet 181 of the inner shroud 60 may be disposed at the forward shroud end 64. L and the shroud end flow passage outlets 182 of the inner shroud 60 may be located at the aft shroud end 64. T In this embodiment, the first air channel 191 and the second air channel 192 may be disposed at the forward shroud end 64. LThe third air channel 193 and the fourth air channel 194 are connected to the shroud end flow passage inlet 181 of the inner shroud 60 located at the aft shroud end 74. T The outer shroud 70 is connected to the shroud end flow passage inlet 171 disposed at the outer shroud 70 .

[0047] Next, a sixth embodiment of the present application will be described below. Figures 13A and 13B are schematic cross-sectional views of a stator vane according to the sixth embodiment. In this embodiment, the outer shroud 70 has two shroud end flow passage inlets (forward shroud end flow passage inlet 171 and forward shroud end flow passage inlet 172). L and aft shroud end flow channel inlet 171 T ) and two shroud end flow passage outlets (ventral shroud end flow passage outlet 172 P and the suction shroud end flow passage outlet 172 N ) is provided. This front shroud end flow path inlet 171 L is the front shroud end 74 L The rear shroud end flow passage inlet 171 is provided at the rear shroud end flow passage inlet 171. T aft shroud end 74 T The ventral shroud end flow passage outlet 172 P is the ventral shroud end 74 P The suction port 172 is provided at the rear shroud end. N is the dorsal shroud end 74 N Each of the air channels 191, 192, 193, 194, and 195 includes an insert and an inner air channel (not shown).

[0048] In this embodiment, the inner shroud 60 has two shroud end flow passage inlets (forward shroud end flow passage inlet 181 and forward shroud end flow passage inlet 182). L and aft shroud end flow channel inlet 181 T ) and two shroud end flow passage outlets (ventral shroud end flow passage outlet 182 P and the dorsal shroud end flow passage outlet 182 N ) is provided. This front shroud end flow passage inlet 181 L is the front shroud end 64 LThe rear shroud end flow passage inlet 181 is provided at T aft shroud end 64 T The ventral shroud end flow path outlet 182 is provided at P is the ventral shroud end 64 P The suction port 182 is provided at the rear shroud end. N is the dorsal shroud end 64 N It is set up in.

[0049] As shown in FIG. 13A, the first air channel 191 is located at the forward shroud end 74 L The shroud end flow passage inlet 171 of the outer shroud 70 is disposed L The fourth air channel 194 is in communication with the aft shroud end 74. T The shroud end flow passage inlet 171 of the outer shroud 70 is disposed T As shown in FIG. 13B, the second air channel 192 is in communication with the forward shroud end 64. L The shroud end flow passage inlet 181 of the inner shroud 60 is disposed L The third air channel 193 is in communication with the aft shroud end 64. T The shroud end flow passage inlet 181 of the inner shroud 60 is disposed T It is connected to:

[0050] In this embodiment, for example, a portion of the cooling air supplied to the first air channel 191 is injected from the first inner air channel through the first insert holes 59 toward the inner surface of the leading end of the airfoil 51, and then directed to flow radially outward through its outer air channel 57 toward the outer shroud 70. As shown in FIG. 13A, the cooling air is then directed to flow radially outward through the forward shroud end flow passage inlet 171. L The cooling air then flows into the forward shroud end channel 75 L The cooling air then flows along the ventral shroud end flow passage 75 P and then flows along the ventral shroud end flow channel outlet 172 P or the back shroud end flow passage 75N and then flows along the suction shroud end flow channel outlet 172 N In this embodiment, for example, a portion of the cooling air supplied to the fourth air channel 194 is injected from the fourth inner air channel through the holes 59 in the fourth insert toward the inner surface of the central portion of the airfoil 51, and then directed to flow radially outward through its outer air channel 57 toward the outer shroud 70. As shown in FIG. 13A, the cooling air then exits the aft shroud end flow passage inlet 171. T The cooling air then flows into the aft shroud end channel 75 T The cooling air then flows along the ventral shroud end flow passage 75 P and then flows along the ventral shroud end flow channel outlet 172 P or the back shroud end flow passage 75 N and then flows along the suction shroud end flow channel outlet 172 N It flows out from.

[0051] In this embodiment, for example, a portion of the cooling air supplied to the second air channel 192 is injected from the second inner air channel through the holes 59 in the second insert toward the inner surface of the central portion of the airfoil 51, and then directed to flow radially inward through its outer air channel 57 toward the inner shroud 60. As shown in FIG. 13B, the cooling air is then directed to flow radially inward through the forward shroud end flow passage inlet 181. L The cooling air then flows into the forward shroud end channel 65 L The cooling air then flows along the ventral shroud end flow passage 65 P and then flows along the ventral shroud end flow channel outlet 182 P or back shroud end flow passage 65 N and then flows along the suction shroud end flow channel outlet 182 NIn this embodiment, for example, a portion of the cooling air supplied to the third air channel 193 is injected from the third inner air channel through the holes 59 in the third insert toward the inner surface of the central portion of the airfoil 51, and is then directed to flow radially inward through its outer air channel 57 toward the inner shroud 60. As shown in FIG. 13B, the cooling air is then directed to flow radially inward through the aft shroud end flow passage inlet 181. T The cooling air then flows into the aft shroud end channel 65 T The cooling air then flows along the ventral shroud end flow passage 65 P and then flows along the ventral shroud end flow channel outlet 182 P or back shroud end flow passage 65 N and then flows along the suction shroud end flow channel outlet 182 N It flows out from.

[0052] The fifth air channel 195 is an aft end air channel located at the downstream end of the vane body 51. As previously mentioned, in the fifth air channel 195, a portion of the cooling air supplied to the fifth inner air channel through the air intake 58 is injected through the holes 59 toward the inner surface of the aft end of the airfoil 51 and then directed to flow to the airfoil cooling structure 154. A portion of the cooling air flows through passages including the pin fins 164 and is then discharged into the hot gas path at the trailing edge 53 of the airfoil 51.

[0053] The structure of the vane is not limited to this embodiment. In an alternative embodiment, the first air channel 191 is located at the forward shroud end 64. L The shroud end flow passage inlet 181 of the inner shroud 60 is disposed L The fourth air channel 194 may also be in communication with the aft shroud end 64. T The shroud end flow passage inlet 181 of the inner shroud 60 is disposed T The second air channel 192 may also be in communication with the forward shroud end 74. L The shroud end flow passage inlet 171 of the outer shroud 70 is disposedL The third air channel 193 may also be in communication with the aft shroud end 74. T The shroud end flow passage inlet 171 of the outer shroud 70 is disposed T It may be in communication with.

[0054] The present disclosure is not limited to the above-described embodiments and can be implemented in various embodiments. For better understanding, specific embodiments have been described with reference to the drawings. However, the above description is provided by way of example only and does not limit the scope of the invention as defined by the appended claims. The scope of the present invention should be determined by the appended claims. Those skilled in the art can make various modifications without departing from the scope of the invention, and the appended claims are intended to cover such modifications. [Explanation of symbols]

[0055] 10. Gas turbine 20 Turbine 22 Turbine case 24 rotor shaft 26 Turbine rotor Ar axis 30 Combustor 50 Stator blade 51 Stator wing body (airfoil) 51 P bulkhead 52 leading edge 53 Trailing edge 54 Dorsal aspect 55 Ventral aspect 56 Intake manifold 57 outer air channel 58 Air intake 59 Hole 141,142,143 Air Channel 151,152,153 Insert 161,162,163 Inner air channel 191,192,193,194,195 Air Channel 154 Airfoil Cooling Structure 164 Pinfin 60 Inner shroud 70 Outer shroud 62, 72 Shroud body 63, 73 Impingement plate 64, 74 Shroud end 65, 75 Shroud end flow passage S space 171 Shroud end flow passage inlet 172 Shroud end flow passage outlet 175 Turbulator 76 Peripheral wall 78 Gas Pass Surface 79 Impingement cooling holes 81 radial inner wall 82 radial outer wall 83 Discharge pipe 181 Shroud end flow passage inlet 182 Shroud end flow passage outlet

Claims

1. A turbine vane, Airfoil and a shroud provided at an end of the airfoil in a radial direction of the turbine; the shroud includes an outer shroud provided at an outer end of the airfoil in a radial direction of the turbine, and an inner shroud provided at an inner end of the airfoil in a radial direction of the turbine, the airfoil includes a plurality of air channels extending radially of the turbine, the plurality of air channels including a first air channel and a second air channel; the airfoil including an air intake configured to introduce cooling air into the first air channel and the second air channel from a radially outer side of the turbine of the vane; the first air channel is in communication with one of the outer shroud and the inner shroud such that cooling air introduced into the first air channel flows toward the one of the outer shroud and the inner shroud to cool the one of the outer shroud and the inner shroud; the second air channel is in communication with the other of the outer shroud and the inner shroud such that cooling air introduced into the second air channel flows toward the other of the outer shroud and the inner shroud to cool the other of the outer shroud and the inner shroud; the first air channel is a leading end air channel located at an upstream end of the airfoil along a flow direction of hot gas within the turbine; the second air channel is an air channel located downstream of the front end air channel; the first air channel is in communication with the outer shroud so that the outer shroud is cooled using cooling air flowing through the first air channel; The second air channel is in communication with the inner shroud such that the inner shroud is cooled using cooling air flowing through the second air channel.

2. A turbine stator vane, Airfoil and a shroud provided at an end of the airfoil in a radial direction of the turbine; the shroud includes an outer shroud provided at an outer end of the airfoil in a radial direction of the turbine, and an inner shroud provided at an inner end of the airfoil in a radial direction of the turbine, the airfoil includes a plurality of air channels extending radially of the turbine, the plurality of air channels including a first air channel and a second air channel; the airfoil including an air intake configured to introduce cooling air into the first air channel and the second air channel from a radially outer side of the turbine of the vane; the first air channel is in communication with one of the outer shroud and the inner shroud such that cooling air introduced into the first air channel flows toward the one of the outer shroud and the inner shroud to cool the one of the outer shroud and the inner shroud; the second air channel is in communication with the other of the outer shroud and the inner shroud such that cooling air introduced into the second air channel flows toward the other of the outer shroud and the inner shroud to cool the other of the outer shroud and the inner shroud; the outer shroud includes an outer shroud body and an outer shroud end portion disposed around the outer shroud body so as to surround the outer shroud body, the outer shroud end portion having an outer shroud end flow passage therein; the inner shroud includes an inner shroud body and an inner shroud end portion disposed around the inner shroud body so as to surround the inner shroud body, the inner shroud end portion having an inner shroud end flow passage therein; the first air channel is in communication with the outer shroud end flow passage; The vane, wherein the second air channel is in communication with the inner shroud end flowpath.

3. the outer shroud end includes an outer shroud end flow passage inlet disposed at a forward end of the outer shroud end, the first air channel communicating with the outer shroud end flow passage through the outer shroud end flow passage inlet; 3. The vane of claim 2, wherein the inner shroud end includes an inner shroud end flow passage inlet disposed at an aft end of the inner shroud end, the second air channel communicating with the inner shroud end flow passage through the inner shroud end flow passage inlet.

4. the outer shroud end includes an outer shroud end flow passage inlet disposed at a forward end of the outer shroud end, the first air channel communicating with the outer shroud end flow passage through the outer shroud end flow passage inlet; 3. The vane of claim 2, wherein the inner shroud end includes an inner shroud end flow passage inlet located at a forward end of the inner shroud end, the second air channel communicating with the inner shroud end flow passage through the inner shroud end flow passage inlet.

5. the airfoil further includes an aft air channel located at a downstream end of the airfoil along a flow of hot gases within the turbine; the aft-end air channel extends along a radial direction of the turbine and has an exhaust port disposed at a downstream end thereof; 2. The vane of claim 1, wherein the outlet opens to a hot gas path of the turbine such that cooling air flows through the aft end air channel to cool the aft end air channel and then is discharged through the outlet into a hot gas path of the turbine.

6. the air intake is configured to receive cooling air extracted from an interior of the combustor casing and compressed by an external compressor; The vane of claim 1 or 2, wherein the outer shroud and the inner shroud each include a discharge passage configured to discharge cooling air into the interior of the combustor casing.

7. 7. The vane of claim 6, wherein the air intake is configured to introduce cooling air from inside the combustor casing into the first air channel and the second air channel without passing through the outer shroud or the inner shroud.

8. 1. A method for cooling a turbine vane, comprising: The turbine includes an airfoil and a shroud provided at an end of the airfoil in a radial direction of the turbine, the shroud includes an outer shroud provided at an outer end of the airfoil in a radial direction of the turbine and an inner shroud provided at an inner end of the airfoil in the radial direction of the turbine, the airfoil having a plurality of air channels extending along the radial direction of the turbine, the plurality of air channels including a first air channel and a second air channel; The cooling method for the stator blade includes: cooling the first air channel by flowing cooling air through the first air channel, and cooling one of the outer shroud and the inner shroud using the cooling air flowing through the first air channel; cooling the second air channel by flowing cooling air through the second air channel, and cooling the other of the outer shroud and the inner shroud using the cooling air flowing through the second air channel; the first air channel is a leading end air channel located at an upstream end of the airfoil along a flow direction of hot gas within the turbine; the second air channel is an air channel located downstream of the front end air channel; the outer shroud is cooled using cooling air flowing through the first air channel; The method for cooling a stator vane, wherein the inner shroud is cooled using the cooling air that has flowed through the second air channel.

9. A method for cooling a turbine vane, comprising: The turbine includes an airfoil and a shroud provided at an end of the airfoil in a radial direction of the turbine, the shroud includes an outer shroud provided at an outer end of the airfoil in a radial direction of the turbine and an inner shroud provided at an inner end of the airfoil in the radial direction of the turbine, the airfoil having a plurality of air channels extending along the radial direction of the turbine, the plurality of air channels including a first air channel and a second air channel; The cooling method for the stator blade includes: cooling the first air channel by flowing cooling air through the first air channel, and cooling one of the outer shroud and the inner shroud using the cooling air flowing through the first air channel; cooling the second air channel by flowing cooling air through the second air channel, and cooling the other of the outer shroud and the inner shroud using the cooling air flowing through the second air channel; the outer shroud includes an outer shroud body and an outer shroud end portion disposed around the outer shroud body so as to surround the outer shroud body, the outer shroud end portion having an outer shroud end flow passage therein; the inner shroud includes an inner shroud body and an inner shroud end portion disposed around the inner shroud body so as to surround the inner shroud body, the inner shroud end portion having an inner shroud end flow passage therein; the cooling air flowing through the first air channel is introduced into the outer shroud end flow passage through a forward end of the outer shroud end to cool the outer shroud end; the cooling air that has flowed inside the second air channel is introduced into the inner shroud end flow passage through an aft end of the inner shroud end to cool the inner shroud end.

10. the outer shroud includes an outer shroud body and an outer shroud end portion disposed around the outer shroud body so as to surround the outer shroud body, the outer shroud end portion having an outer shroud end flow passage therein; the inner shroud includes an inner shroud body and an inner shroud end portion disposed around the inner shroud body so as to surround the inner shroud body, the inner shroud end portion having an inner shroud end flow passage therein; the cooling air flowing through the first air channel is introduced into the outer shroud end flow passage through a forward end of the outer shroud end to cool the outer shroud end; 9. The method for cooling a stator vane according to claim 8, wherein the cooling air flowing inside the second air channel is introduced into the inner shroud end flow passage through a forward end of the inner shroud end to cool the inner shroud end.

11. The airfoil further includes a trailing air channel located at a downstream end of the airfoil along a flow of hot gas within the turbine, the trailing air channel extending radially of the turbine; The cooling method for the stator blade includes:

9. The method of cooling a stator vane of claim 8, further comprising: flowing cooling air into the aft end air channel to cool the aft end air channel; and then discharging the cooling air that has flowed within the aft end air channel into a hot gas path of the turbine through an outlet located at a downstream end of the aft end air channel.

12. 10. The method for cooling a stator vane according to claim 8, further comprising the step of introducing cooling air from outside the stator vane into the first air channel and the second air channel without passing through the outer shroud or the inner shroud.

13. introducing cooling air extracted from an interior of a combustor casing and compressed by an external compressor into the first air channel and the second air channel; The method of cooling a vane according to claim 8 or 9, further comprising the step of discharging cooling air from the outer shroud and the inner shroud into the interior of the combustor casing.

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