JP2001207802A - Gas turbine stationary blade and gas turbine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an easily and inexpensively constituted gas turbine stationary blade having favorable cooling efficiency and reliability, and to provide a gas turbine having high reliability and easily extendable in a service life. SOLUTION: The stationary blade S3 provided in a turbine 3 constituting the gas turbine 1 has a serpentine passage 16 in a blade part 14 sandwiched by an outer shroud 11 and an inner shroud 12, and a cooling fluid C can be circulated inside this serpentine passage 16. The serpentine passage 16 includes a leading edge-most side passage 16a extending along a leading edge of the blade part 14, and a passage narrowing member 17 narrowing a passage area is provided in a region including a vicinity of a leading edge root part 14b of the blade part 14 in the outer shroud 11 side of the leading edge-most side passage 16a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas turbine stationary blade having a cooling function and a gas turbine provided with such a stationary blade.

[0002]

2. Description of the Related Art Conventionally, gas turbines that generate power by expanding a fluid compressed by a compressor between a stationary blade and a moving blade of a turbine have been widely used in various fields. In this type of gas turbine, it is possible to improve performance by cooling various components and setting the turbine inlet temperature high. For this reason, conventionally, a turbine having a cooling function is known as a stationary blade (gas turbine stationary blade) of a turbine constituting a gas turbine. An example of such a gas turbine vane is disclosed in, for example, JP-A-10-220203.

[0003] The gas turbine vane described in the publication is
It has a wing portion sandwiched between an outer shroud and an inner shroud. A plurality of partition walls are provided inside the wing portion, and a serpentine flow path is defined by each of the partition walls, the outer shroud, the inner shroud, and the inner peripheral surface of the wing portion. The serpentine flow path communicates with a fluid inlet formed at the leading edge of the outer shroud and extends along the leading edge of the wing. Further, the serpentine flow path is sequentially turned upside down (inverted) on the inner shroud side and the outer shroud side, and communicates with a plurality of fluid outlets (slot holes) provided at the trailing edge of the wing. Accordingly, if a cooling fluid (for example, air or steam extracted from between compressor stages) flows through the serpentine flow path, it becomes possible to cool the gas turbine stationary blades (blades).

[0004]

However, the conventional gas turbine stationary blade configured as described above has the following problems. That is, in a conventional gas turbine stationary blade, a cooling fluid is circulated through a serpentine flow passage to cool a blade or the like, but even in this case, the vicinity of the leading edge root of the blade on the outer shroud side (near the fluid inlet). ) Temperature rises.

Here, during the operation of the gas turbine, a tipping moment acts on the stationary blades of the turbine in the direction of rotation from the inner shroud side to the outer shroud side along the flow direction of the working fluid. Therefore, if the temperature near the leading edge root portion of the wing on the outer shroud side becomes high, the stress applied to the location increases, and in some cases, cracks and the like may occur. As described above, the conventional gas turbine stationary blades have problems in terms of cooling efficiency, reliability, and the like, and these are one of the factors that hinder a long life of the gas turbine.

Therefore, the present invention is to provide a gas turbine vane which has good cooling efficiency and reliability, and can be configured simply and at low cost, and has high reliability and can easily achieve a long life. The purpose of the present invention is to provide a gas turbine capable of performing the above.

[0007]

According to a first aspect of the present invention, there is provided a gas turbine stationary blade having a serpentine flow path in a blade portion sandwiched between an outer shroud and an inner shroud, and cooling in the serpentine flow path. In a gas turbine vane through which fluid can flow, the serpentine flow path includes a leading edge side flow path extending along the leading edge of the blade part, and the leading edge of the blade part on the outer shroud side among the foremost edge side flow path. A flow path narrowing member for narrowing the flow path area is provided in a region including the vicinity of the base.

[0008] The gas turbine stationary blade is capable of cooling the wing and the like by flowing a cooling fluid through a serpentine flow path formed in the wing. The leading edge of the wing is included in the serpentine flow path. A flow path narrowing member is provided in the forefront edge side flow path extending along. The channel narrowing member is arranged in a region including the vicinity of the leading edge root of the blade on the outer shroud side, and narrows the channel area.

In the gas turbine stationary blade configured as described above, if the cooling fluid is introduced into the serpentine flow path, the flow velocity of the cooling fluid flowing through the frontmost flow path near the leading edge root of the blade increases. Therefore, the heat transfer coefficient at the location increases. As a result, it is possible to efficiently cool the vicinity of the leading edge root, which becomes hot during operation of the gas turbine, and reduce the stress generated near the leading edge root, thereby improving the reliability of the gas turbine stationary blade. Can be done. In addition, since the flow path narrowing member may be appropriately arranged (fixed) in the frontmost flow path near the leading edge root, the gas turbine vane can be configured simply and at low cost. Further, the flow path narrowing member can be easily applied to an existing gas turbine stationary blade.

The flow channel narrowing member is formed as a cylindrical body having a bottom portion located on the inner shroud side and an outer wall portion, and has a plurality of impingement holes provided on the outer wall portion. It is preferable that the gas is supplied to the inside of the channel narrowing member.

With such a configuration, the cooling fluid supplied into the flow path narrowing member is sprayed onto the inner peripheral surface of the wing near the leading edge through a plurality of impingement holes. Therefore, it is possible to more efficiently cool the vicinity of the leading edge root of the wing, which becomes hot.

Further, it is preferable that the respective impingement holes are arranged so that the resistance to the cooling fluid increases from the outer shroud toward the inner shroud.

That is, in this case, the diameter of each impingement hole is reduced or the arrangement density of the impingement holes is reduced from the outer shroud toward the inner shroud.
This makes it possible to increase the supply amount of the cooling fluid to the region on the outer shroud side where the temperature becomes higher even in the vicinity of the leading edge root portion of the wing portion, and it is possible to efficiently cool the portion.

[0014] It is preferable that a plurality of rib members are provided to contact the outer peripheral surface of the flow path narrowing member and the inner peripheral surface of the blade portion.

If such a configuration is adopted, each rib material functions as a so-called cooling fin, and since cold heat is transmitted from the rib material to the wing, the leading edge of the wing becomes hot. It is possible to cool the vicinity of the base more efficiently.

Further, it is preferable that the flow path narrowing member is formed so as to increase the flow path area of the frontmost flow path from the outer shroud toward the inner shroud.

By adopting such a configuration, it is possible to further increase the flow rate of the cooling fluid in the region on the outer shroud side where the temperature becomes higher even in the vicinity of the leading edge root portion of the wing portion, and the heat transfer at that portion The rate can be increased. Further, it is possible to reduce the pressure loss of the cooling fluid in the leading edge side flow path.

According to a sixth aspect of the present invention, there is provided a gas turbine for generating power by expanding a fluid compressed by a compressor between a stationary blade and a moving blade of the turbine. , Outer shroud,
An inner shroud, and a wing in which a serpentine flow path for flowing a cooling fluid is formed. Of these, a flow path narrowing member for narrowing the flow path area is provided in a region including the vicinity of the leading edge root of the wing on the outer shroud side.

The gas turbine stationary blades provided in the turbine constituting this gas turbine can be simply and inexpensively constructed, and have high cooling efficiency and reliability. Therefore, if such a gas turbine vane is provided for the gas turbine, the reliability of the gas turbine itself can be improved and the life can be easily extended.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a gas turbine stationary blade and a gas turbine according to the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic diagram showing a gas turbine according to the present invention. The gas turbine 1 shown in FIG. 1 includes a compressor 2 and a turbine 3 directly connected to each other. Compressor 2
Is configured as, for example, an axial compressor, and sucks air or a predetermined gas as a working fluid from a suction port to increase the pressure. A combustor 4 is connected to a discharge port of the compressor 2, and the working fluid discharged from the compressor 2 is heated by the combustor 4 to a predetermined turbine inlet temperature. Then, the working fluid heated to the predetermined temperature is supplied to the turbine 3.

As shown in FIG. 1, a turbine 3 includes a plurality of stationary blades S1, S2, S
3, S4. Further, on the main shaft 6 of the turbine 3, a moving blade R that forms a set of stages with each of the stationary blades S <b> 1 to S <b> 4 respectively.
1, R2, R3, and R4 are attached. One end of the main shaft 6 is connected to the rotating shaft of the compressor 2, and the other end is connected to the rotating shaft of the generator 7.

Thus, when a high-temperature and high-pressure working fluid is supplied from the combustor 4 into the casing 5 of the turbine 3, the working fluid expands in the casing 5, whereby the main shaft 6 rotates and the generator 7 is driven. Is done. That is, the working fluid supplied into the casing 5 is pressure-decreased by the stationary blades S1 to S4 fixed to the casing 5, and the kinetic energy generated thereby is reduced by the moving blades R1 attached to the main shaft 6. Is converted into rotational torque through R4. Then, the rotational torque generated by each of the moving blades R1 to R4 is transmitted to the main shaft 6, and the generator 7 is driven.

In this type of gas turbine, it is possible to improve the performance by cooling various constituent members and setting the turbine inlet temperature high. For this reason, in this gas turbine 1, each stationary blade (gas turbine stationary blade) S1
-S4 are all configured to have a cooling function. Hereinafter, the gas turbine stationary blade according to the present invention will be described using the third stage stationary blade S3 of the gas turbine 1 as an example.

FIG. 2 is a sectional view showing the third stage stationary blade S3 of the turbine 3 constituting the gas turbine 1. As shown in FIG. As shown in the figure, the stationary blade S3 has an outer shroud 11 fixed to the casing 5 of the turbine 3 and an inner shroud 12 located on the main shaft 6 side. These outer shroud 11 and inner shroud 12 The wing portion 14 is sandwiched by these. The wing part 14 is formed in a hollow shape, and one end (the upper end in the figure) is fixed to the outer shroud 11, and the other end (the lower end in the figure) is fixed to the inner shroud 12. .

The stationary blade S3 is provided with a plurality (four in this case) of partition walls 15 that partition the inside of the wing portion 14. That is, each of the partition walls 15 has the outer shroud 1
It has an overall length shorter than the distance between 1 and the inner shroud 12 and is alternately fixed to the outer shroud 11 or the inner shroud 12 at a predetermined interval. As a result, a serpentine channel 16 is defined by each partition wall 15, the outer shroud 11, the inner shroud 12, and the inner peripheral surface of the wing 14. Serpentine channel 16
Is a leading edge side flow path 16 a extending along the leading edge of the wing portion 14.
And the inner shroud 12 side and the outer shroud 11
It is inverted on the side. The serpentine flow path 16 is provided with a plurality of turbulators (not shown).

A fluid inlet 11a communicating with the serpentine flow path 16 is formed at the end of the outer shroud on the leading edge side of the wing portion 14. The fluid inlet 11a is compressed by a pipe or the like. Air, steam, and the like extracted from between the stages of the machine 2 are introduced as the cooling fluid C. On the other hand, a plurality of fluid outlets (slot holes) 14a are provided at the trailing edge of the wing portion 14, and the serpentine flow path 16 communicates with each of the fluid outlets 14a. Accordingly, when the cooling fluid C is introduced into the fluid inlet 11a, the cooling fluid C cools the stationary blade S3 (wing portion 14) while flowing through the serpentine flow path 16, and flows from the respective fluid outlets 14a to the blade portion 14. Is discharged to the outside.

Here, in the stationary blade S3 located at the third stage of the turbine 3 configured as described above, the vicinity of the leading edge root portion 14b of the blade portion 14 on the outer shroud 11 side (the vicinity of the fluid inlet 11a). The temperature rises. Based on this, in the stationary blade S3, as shown in FIGS. 2 and 3, the leading edge side channel 1 included in the serpentine channel 16 is provided.
6a, a region including the vicinity of the leading edge 14b of the wing portion 14 on the outer shroud 11 side is provided in the flow channel narrowing member 17;
Is arranged. As shown in FIGS. 4 and 5, the channel narrowing member 17 is formed in a cylindrical shape by, for example, metal and has an outer wall portion 17a.

The flow channel narrowing member 17 is connected to the front edge side flow channel 16a.
When disposing them, it is preferable to use a stay 18 as shown in FIGS. 4 and 5 (in this case, two members). Stay 18
Has two legs, and the tip of each leg is bent to form a fixed portion 18a. In this case, it is preferable that the entire circumference of each fixing portion 18a of the stay 18 and the upper surface of the outer shroud 11 be welded, and the rear surface of the outer wall portion 17a of the flow path narrowing member 17 be welded to the partition wall 15 (see FIG. 5). ×
Xx section).

As shown in FIG. 3, the channel narrowing member 17
Is configured to reduce the flow area (cross-sectional area) of the forefront edge flow path 16a to about one half of the original flow area when disposed in the forefront flow path 16a. . Further, the overall height of the flow path narrowing member 17 is determined according to the height H (see FIG. 2) of a region including the vicinity of the leading edge root portion 14b of the wing portion 14 on the outer shroud 11 side. The height H is, for example, about 20 to 40 times the height of the leading edge of the wing portion 14.
% (In the present embodiment, about 25%), but is arbitrarily determined according to the size of the stationary blade.

In the third stage stationary blade S3 of the turbine 3 configured as described above, if the cooling fluid C such as compressed air extracted from between the stages of the compressor 2 is introduced into the serpentine flow path 16, the front of the blade section 14 In the vicinity of the rim portion 14b, the flow velocity of the cooling fluid C flowing through the foremost edge side flow path 16a increases,
The heat transfer coefficient at the location will increase. This makes it possible to efficiently cool the vicinity of the leading edge root 14b, which becomes high during operation of the gas turbine, and reduce the stress generated near the leading edge root 14b.
The reliability of the stationary blade S3 can be improved. In addition, since the flow path narrowing member 17 only needs to be appropriately arranged (fixed) in the forefront edge side flow path 16a in the vicinity of the leading edge root portion 14b, the stationary blade S3 can be configured simply and at low cost.

As described above, the stationary blade S3 provided in the turbine 3 constituting the gas turbine 1 can be simply and inexpensively configured, and has high cooling efficiency and reliability. Accordingly, if such a stationary blade S3 is provided for the gas turbine 1, the reliability of the gas turbine 1 itself can be improved, and the life can be easily increased. Furthermore, the channel narrowing member 17 is
It can be easily applied to existing gas turbine vanes.

FIG. 6 is a sectional view showing another flow path narrowing member applicable to the stationary blade S3 provided in the turbine 3 constituting the gas turbine 1. As shown in FIG. The flow channel narrowing member 17A shown in the figure is formed as a bottomed cylindrical body having an outer wall 17a and a bottom 17b located on the inner shroud 12 side. As shown in FIG. 6, a plurality of impingement holes 17c are provided on the outer wall 17a of the flow channel narrowing member 17A. Further, inside the flow channel narrowing member 17A, from the outer shroud 11 side (the side opposite to the bottom portion 17b),
Air, steam, and the like extracted from between the stages of the compressor 2 are introduced as a cooling fluid C via piping or the like.

The flow path narrowing member 17 thus configured
If A is used, the cooling fluid C supplied into the flow channel narrowing member 17A is sprayed onto the inner peripheral surface of the wing portion 14 near the leading edge root portion 14b through the plurality of impingement holes 17c. Therefore, the vicinity of the leading edge root portion 14b of the wing portion 14, which becomes hot, can be cooled more efficiently.

Here, the impingement hole 17 is formed in the outer wall 17a.
7, the impingement holes 1 are arranged from the outer shroud 11 side toward the inner shroud 12 side (from top to bottom in the figure), as shown in FIG.
7c, or the outer wall 17a as shown in FIG.
It is preferable to reduce the arrangement density of the impingement holes 17c per unit area in.

In other words, if the impingement holes 17c are arranged so that the resistance to the cooling fluid C increases from the outer shroud 11 side to the inner shroud 12 side, the impingement holes 17c can be located in the vicinity of the leading edge root portion 14b of the wing portion 14. The supply amount of the cooling fluid C to the region on the outer shroud 11 side where the temperature becomes higher can be increased. Thereby, the said part can be cooled efficiently.

As shown in FIGS. 7 and 8, the flow path narrowing member 17A is arranged such that the flow path area (see FIG. 2) of the frontmost flow path 16a (see FIG. 2) moves from the outer shroud 11 side to the inner shroud 12 side. (Cross-sectional area) may be formed. In this case, specifically, the wing 1
The flow channel narrowing member 17A is formed so that the width d in the span direction of 4 increases from the outer shroud 11 side to the inner shroud 12 side.

By employing such a configuration, it is possible to further increase the flow rate of the cooling fluid C in the region near the outer shroud 11 where the temperature becomes higher even in the vicinity of the leading edge root portion 14b of the wing portion 14. The heat transfer coefficient at the location can be increased. Also, the leading edge side flow path 16a
It is possible to reduce the pressure loss of the cooling fluid C in the above. Note that such a configuration may be applied to the channel narrowing member 17 having no impingement hole illustrated in FIG. 2 and the like.

Further, the flow path narrowing member 1 is arranged with respect to the stationary blade S3.
When attaching 7A, as shown in FIG. 9, a plurality of rib members 20 may be further provided. These rib materials 20
Are arranged so as not to interfere with the impingement hole 17c and to contact both the outer peripheral surface of the outer wall portion 17a of the channel narrowing member 17A and the inner peripheral surface of the wing portion 14.

If such a configuration is adopted, each rib material 2
Numeral 0 functions as a so-called cooling fin, and the cooling heat of the cooling fluid introduced into the flow path narrowing member 17A is transmitted from the rib member 20 to the blade section 14. Therefore,
The vicinity of the leading edge root portion 14b of the wing portion 14, which becomes hot, can be cooled more efficiently. In this case, the stay 18 as shown in FIGS. 4 and 5 may be omitted, and the channel narrowing member 17A may be fixed to the wing portion 14 by the rib member 20. Further, such a configuration can also be applied to the flow path narrowing member 17 having no impingement hole shown in FIG. 2 and the like.

[0041]

The gas turbine stationary blade according to the present invention is configured as described above, and therefore has the following effects. That is, a flow path narrowing member that narrows the flow path area to a region including the vicinity of the leading edge root of the blade section on the outer shroud side with respect to the foremost edge side flow path included in the serpentine flow path of the gas turbine stationary blade. By providing the gas turbine vane, it is possible to realize a gas turbine vane that has good cooling efficiency and reliability and can be configured simply and at low cost. Also, if such a gas turbine stationary blade is applied to a gas turbine,
The reliability of the gas turbine can be improved, and the life can be easily extended.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a gas turbine according to the present invention.

FIG. 2 is a sectional view showing a gas turbine stationary blade according to the present invention.

FIG. 3 is a sectional view taken along line III-III in FIG. 2;

FIG. 4 is a perspective view for explaining a method of attaching a flow path narrowing member.

FIG. 5 is a plan view for explaining a method of attaching a channel narrowing member.

FIG. 6 is a sectional view showing another embodiment of the gas turbine stationary blade according to the present invention.

FIG. 7 is a side view showing another embodiment of the channel narrowing member.

FIG. 8 is a side view showing still another embodiment of the channel narrowing member.

FIG. 9 is a sectional view showing still another embodiment of the gas turbine vane according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Gas turbine, 2 ... Compressor, 3 ... Turbine, 4 ... Combustor, 5 ... Casing, 6 ... Main shaft, 7 ... Generator, 11 ...
Outer shroud, 11a fluid inlet, 12 inner shroud, 14 wing, 14a fluid outlet, 14b leading edge root, 15 partition wall, 16 serpentine channel, 16
a: the leading edge side channel, 17, 17A: channel narrowing member, 1
7a: outer wall portion, 17c: impingement hole, 20: rib material,
C: cooling fluid, R1, R2, R3, R4: rotor blades, S1,
S2, S4: stationary blade, S3: third stage stationary blade.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Masato Kataoka 2-1-1 Shinhama, Arai-machi, Takasago-shi, Hyogo F-term in Mitsubishi Heavy Industries, Ltd. Takasago Works 3G002 GA08 GB01

Claims (6)

[Claims] 1. A gas turbine vane having a serpentine flow path in a blade section sandwiched between an outer shroud and an inner shroud, and allowing a cooling fluid to flow in the serpentine flow path, wherein the serpentine flow path is A leading edge side channel extending along the leading edge of the wing portion, a region of the foremost edge side channel including a portion near the leading edge root of the wing portion on the outer shroud side has a channel area. A gas turbine stationary blade provided with a channel narrowing member for narrowing. 2. The flow path narrowing member is formed as a cylindrical body including a bottom portion located on the inner shroud side and an outer wall portion, and has a plurality of impingement holes provided in the outer wall portion, 2. The gas turbine vane according to claim 1, wherein the cooling fluid is supplied into the flow path narrowing member. 3. 3. The gas turbine according to claim 2, wherein each of the impingement holes is arranged such that a resistance to the cooling fluid increases from the outer shroud toward the inner shroud. Stationary wing. 4. The gas turbine stator according to claim 1, further comprising a plurality of rib members abutting on an outer peripheral surface of the flow path narrowing member and an inner peripheral surface of the blade. Wings. 5. The flow path narrowing member is formed so as to increase the flow path area of the forefront side flow path from the outer shroud to the inner shroud. The gas turbine stationary blade according to any one of the above. 6. A gas turbine that generates power by expanding fluid compressed by a compressor between a stationary blade and a moving blade of a turbine, wherein the stationary blade of the turbine includes an outer shroud, an inner shroud, and It has a wing portion in which a serpentine flow channel for flowing a cooling fluid is formed, and the serpentine flow channel includes a forefront edge side flow channel extending along a front edge of the wing portion, among the foremost edge side flow channel, A gas turbine characterized in that a flow channel narrowing member for narrowing a flow channel area is provided in a region including a vicinity of a leading edge root portion of the wing on the outer shroud side.