JP4064778B2 - Gas turbine blade body and gas turbine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a moving blade or a stationary blade of a gas turbine, and more particularly to a cooling structure thereof.
[0002]
[Prior art]
FIG. 9 is a typical cross-sectional view of a first stage blade of a conventional gas turbine. In the figure, reference numeral 1 is a moving blade, 2 is a blade root, and 3 is a platform. Inside the rotor blade 1, a serpentine cooling flow path including cooling passages 4a, 5a, 5b, 5c, 6a, 6b and 6c is formed. The blade root 2 is provided with cooling passages 4, 5, 6, and 7 independently. The cooling passage 4 is located on the leading edge side (left side in the drawing) and communicates with the cooling passage 4a in the blade. Cooling air 10 flows into the cooling passage 4 from the rotor side, cools the leading edge in the process of passing through the cooling passage 4a, and then flows out of the cooling hole 19 to cool the leading edge of the shower head film. Cooling air 11 flows into the cooling passage 5, passes through the cooling passage 5 a in the blade, turns 180 ° at the U-turn portion 15 on the turbine outer diameter side (upper drawing), and flows into the cooling passage 5 b. Then, the U-turn portion 16 on the turbine inner diameter side (downward in the drawing) turns upward again to flow into the cooling passage 5c, and flows out from the tip portion. In this process, the film is cooled by flowing out from the cooling hole 19 described later to the blade surface.
[0003]
The cooling air 12 flows into the cooling passage 6 and the cooling air 43 flows into the cooling passage 7 and merges to flow through the cooling passage 6a. Then, after turning 180 ° at the U-turn portion 17 on the outer diameter side, it enters the cooling passage 6b and then turns upward again at the U-turn portion 18 on the inner diameter side and flows into the cooling flow path 6c. In the course of flowing through the cooling passage 6c, the film flows out to the surface through a cooling hole 23, which will be described later, and film cooling is performed.
FIG. 10 is a cross-sectional view taken along line EE in FIG. 9. As shown in the drawing, a part of the cooling air in the cooling passage 4a at the leading edge flows out from the cooling hole 19 to cool the shower head film. The edge is cooling. In addition, a part of the cooling air flowing in the cooling passage 5c flows obliquely out of the cooling hole 22 in the process of flowing, and cools the film on the surface. Similarly, in the process of flowing in the passage 6c, the cooling air is also inclined from the cooling hole 23. It flows out to the blade surface, and the trailing edge is film-cooled. In the illustrated example, only the cooling holes 19, 22, and 23 are shown, but many other cooling holes are provided. In addition, the following patent document 1 is mentioned as a well-known literature of this kind of conventional cooling passage.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 2000-265802
[Problems to be solved by the invention]
By the way, when the cooling air meanders through the serpentine cooling flow path, the flow direction is suddenly turned at the U-turn portion as shown in FIG. For this reason, there existed a problem that a pressure loss will arise.
[0006]
The present invention has been made in view of the above circumstances, and an object thereof is to provide a gas turbine blade body and a gas turbine capable of reducing pressure loss.
[0007]
[Means for Solving the Problems]
According to the first aspect of the present invention, in the blade body of the gas turbine having a serpentine cooling flow path therein, the serpentine flow path is divided into one or more partition bodies to form a meandering flow path, and The end of one or more of the partitions that form the meandering flow path is provided with an enlarged diameter portion that swells in the U-turn direction of the flow. A recess is formed at the end in the channel width direction .
[0008]
In the present invention, the cooling air is guided by the expanded diameter portion and the turning radius thereof is increased, so that the pressure loss is reduced.
In addition, as a partition plate of a serpentine cooling channel having an enlarged edge, Japanese Patent Laid-Open No. 2000-265802 can be recognized. However, in this document, the swelled configuration is described only in the drawings, and the operational effects of this swelled configuration are unclear. Therefore, it is difficult to guide the expanded diameter portion of the present invention only from the drawing.
[0009]
According to a second aspect of the present invention, in the gas turbine blade body according to the first aspect, a hollow portion or a concave portion is provided in the expanded diameter portion.
[0010]
In this invention, since the blade can be reduced in weight, the centrifugal stress at the blade root can be reduced particularly when applied to a moving blade.
[0011]
According to a third aspect of the present invention, in the turbine blade body according to the first or second aspect, the flow passage cross-sectional area of the U-turn portion formed by the expanded diameter portion is narrower on the upstream side than on the downstream side. It is characterized by.
[0012]
In the present invention, the pressure loss can be further reduced.
[0013]
According to a fourth aspect of the present invention, in the turbine blade body according to any one of the first to third aspects, the expanded diameter portion and the partition body are smoothly connected, and the flow path disconnection on the upstream side of the expanded diameter portion is performed. Sudden changes in area are alleviated.
[0014]
In the present invention, since the cooling air flows smoothly, the pressure loss can be further reduced.
[0016]
In the present invention, the cooling air flows smoothly by expanding the flow path of the U-turn portion around the wall portions at both ends of the partition having poor air fluidity.
[0017]
A gas turbine according to a fifth aspect includes the turbine blade body according to any one of the first to fourth aspects.
[0018]
Since the gas turbine includes the turbine blade body described above, pressure loss can be reduced.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a typical sectional view of a first stage moving blade (gas turbine blade body) of a gas turbine according to a first embodiment of the present invention. In the figure, 30 is a moving blade, 31 is a blade root, and 32 is a platform. A serpentine cooling channel 35 is formed in the blade. The serpentine cooling channel 35 is divided into a plurality of cooling passages 38a, 39a, 39b, 39c, 40a, 40b, and 40c by a plurality of partitions 36a to 36f that are perpendicular to the turbine main shaft and substantially parallel to each other.
The blade root portion 31 is provided with cooling passages 38, 39, 40, and 41, respectively. The cooling passage 38 is a passage on the front edge side and communicates with the cooling passage 38a.
The cooling passage 39 is continuous with the cooling passage 39a, and the cooling passage 39a is rotated 180 degrees at the U-turn portion 55 at the outer diameter side end portion of the partition and is continuous with the cooling passage 39b. The cooling passage 39b rotates 180 ° at the U-turn portion 56 at the inner diameter side end of the partition 36c and is continuous with the cooling passage 39c.
After joining the cooling passages 40 and 41, similarly, the cooling passage 40a, the U-turn portion 57, the cooling passage 40b, the U-turn portion 58, and the cooling passage 40c are continued.
The outer edges and inner diameter side edges of the partitions 36b, 36c, 36e, and 36f are positioned at the U-turn portions 55 to 58, and are substantially omitted in cross-section as shown in FIG. 2 along the edges. An enlarged diameter portion 45 is formed so as to be circular (note that although the partition 36b is shown in the figure, the other partitions 36c, 36e, and 36f have the same configuration). The diameter of the expanded diameter portion 45 is formed larger than the plate thickness of the partitions 36b, 36c, 36e, and 36f. That is, the expanded diameter portion 45 swells round in the U-turn direction of the flow.
[0020]
In the gas turbine configured as described above, the cooling air flows as follows.
The cooling air 50 flows into the cooling passage 38 from the rotor side, and then flows into the cooling passage 38a. While passing through the cooling passage 38a, the front edge flows out of the cooling hole 59 while cooling the front edge, and the front edge is cooled by the shower head film. The cooling air 51 flows into the cooling passage 39 and then flows into the cooling passage 39a in the blade. And it turns 180 degree | times in the U-turn part 55 by the side of an outer diameter, and flows in into the cooling passage 39b. From the cooling passage 39b, it turns again at the U-turn portion 56 on the inner diameter side, flows into the cooling passage 39c, and flows out from the tip portion. In this process, the film is cooled by flowing out from a cooling hole (not shown) to the blade surface.
[0021]
The cooling air 52 flows into the cooling passage 40 and the cooling air 53 flows into the cooling passage 41, merges, and flows into the cooling passage 40a. The cooling air 52 turns 180 degrees at the U-turn portion 57 on the outer diameter side and flows into the cooling passage 40b. Then, it turns around again at the U-turn portion 58 on the inner diameter side and flows into the cooling passage 40c. In the process of flowing through the cooling passage 40c, the film flows out from the cooling holes (not shown) to cool the film, and the remaining air flows out from the cooling holes 61 in the trailing edge 60 to perform pin fin cooling.
[0022]
Here, when the cooling air flows from the cooling passage 39a into the cooling passage 39b, the cooling air is guided by the expanded portion 45 as shown in FIG. Therefore, a reduction in pressure loss can be realized.
Similarly, when the air flows from the cooling passage 39b to the cooling passage 39c, when it flows from the cooling passage 40a to the cooling passage 40b, and when it flows from the cooling passage 40b to the cooling passage 40c, the cooling air is expanded 45. The pressure loss can be reduced by being guided and rotated.
[0023]
In addition, you may comprise as follows.
What was shown in FIG. 3 is the elements on larger scale of the moving blade of the gas turbine shown as a modification. In this example, only characteristic portions are shown, and the same reference numerals are used for the same configurations as those in the above embodiment, and the description thereof is omitted.
In the drawing, reference numeral 45 'denotes an enlarged diameter portion (note that although the partition body 36b is shown in the figure, the other partition bodies 36c, 36e, and 36f have the same configuration). The diameter of the expanded diameter portion 45 ′ is formed larger than the plate thickness of the partitions 36b, 36c, 36e, and 36f. The expanded diameter portion 45 ′ is smoothly connected to the partition body 36b, and sudden changes in the flow path cross-sectional areas on the upstream side and the downstream side of the expanded diameter portion 45 ′ are alleviated.
By being formed in this way, the cooling air flows smoothly, so that the pressure loss can be further reduced.
Even if only the upstream side of the expanded diameter portion 45 ′ is smoothly connected to the partition body 36b, the pressure loss can be reduced.
[0024]
FIG. 4 is a partially enlarged view of a moving blade of a gas turbine shown as a modified example. In this example, only characteristic portions are shown, and the same reference numerals are used for the same configurations as those in the above embodiment, and the description thereof is omitted.
The outer diameter side and inner diameter side edges of the respective partitions 36b, 36c, 36e, and 36f located at the U-turn portions 55 to 58 are substantially circular in cross-sectional view along the edge. An expanded diameter portion 65 is formed so as to be. A hollow portion 66 is formed inside the expanded diameter portion 65, and an opening 67 is provided at the top of the expanded diameter portion 65, so that the hollow portion 66 is in an open state.
By being formed in this way, the same effect as the above embodiment can be obtained, and the moving blade can be reduced in weight. Therefore, the centrifugal stress at the blade root can be reduced.
[0025]
What was shown in FIG. 5 is the elements on larger scale of the moving blade of the gas turbine shown as a modification. In this example, only characteristic portions are shown, and the same reference numerals are used for the same configurations as those in the above embodiment, and the description thereof is omitted.
The outer diameter side and inner diameter side edges of the respective partitions 36b, 36c, 36e, and 36f located at the U-turn portions 55 to 58 are substantially circular in cross-sectional view along the edge. An enlarged diameter portion 65 ′ is formed so as to be. A hollow portion 66 is formed inside the expanded diameter portion 65 ′, and an opening 67 is provided at the top of the expanded diameter portion 65 ′ so that the hollow portion 66 is in an open state.
The diameter of the expanded diameter portion 65 ′ is larger on the downstream side than on the upstream side, so that the flow path of the U-turn portion 56 is narrower on the upstream side than on the downstream side.
By being formed in this way, the cooling air can flow more smoothly and pressure loss can be reduced.
[0026]
FIG. 6 is a cross-sectional view of a turbine blade body as another embodiment. In addition, about the structure same as the said embodiment, the same code | symbol is used and the description is abbreviate | omitted. In the drawing, the arrows indicate the flow of cooling air.
In the figure, reference numerals 62a to 62d denote partition bodies. The serpentine cooling flow path 35 is partitioned by a plurality of partitions 62a to 62d to form a meandering flow path, and the flow paths are provided at the edges of the partition bodies 62b and 62c on the turbine outer diameter side and inner diameter side of the blade body, respectively. Are provided with U-turn portions 63 and 64 that are rotated about 180 degrees.
Similar to FIG. 3, the expanded diameter portion 45 ′ is smoothly connected to the partition body 62 b, and sudden changes in the flow path cross-sectional areas on the upstream side and the downstream side of the expanded diameter portion 45 ′ are alleviated.
Moreover, as for the flow path of the U-turn parts 63 and 64, the upstream side is narrower than the downstream side.
FIG. 7 is an enlarged view in the case where the expanded diameter portion is an example of FIG.
8 is a cross-sectional view taken along the line AA in FIG. Concave portions 46 are provided at both ends of the flow path width direction at the edge of the partition 62b.
As described above, the recess 46 is provided around the wall portions at both ends of the partition with poor air fluidity to widen the flow path of the U-turn portion, so that the cooling air flows smoothly. Therefore, the pressure loss can be further reduced.
[0027]
In each of the above examples, the moving blade has been described, but it goes without saying that it may be applied to a stationary blade. Of course, the above embodiments may be used in combination.
Furthermore, in the gas turbine to which the above embodiment is applied, the pressure loss of the cooling air in the turbine blade body can be reduced.
[0028]
【The invention's effect】
As described above, the following effects can be obtained in the present invention.
According to the first aspect of the present invention, the cooling air is guided by the expanded diameter portion, and the turning radius is increased. Therefore, pressure loss can be reduced.
According to the second aspect of the present invention, since the expanded diameter portion is provided with a hollow portion or a concave portion, the blade can be reduced in weight, and particularly when applied to a moving blade, the centrifugal stress at the blade root portion is reduced. can do.
According to invention of Claim 3, the pressure loss of cooling air can further be reduced.
According to the fourth aspect of the present invention, since the cooling air flows smoothly, the pressure loss can be further reduced.
According to the fifth aspect of the present invention, the cooling air flows smoothly by expanding the flow path of the U-turn portion around the wall portions at both ends of the partition having poor air fluidity. Therefore, the pressure loss can be further reduced.
According to the invention described in claim 6, since the turbine blade body according to any one of claims 1 to 5 is provided, a gas turbine that reduces pressure loss can be obtained.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a moving blade of a gas turbine shown as an embodiment of the present invention. FIG. 2 is a partially enlarged view of the moving blade.
FIG. 3 is a partial enlarged cross-sectional view of a moving blade of a gas turbine shown as a modification of the present invention.
FIG. 4 is a partial enlarged cross-sectional view of a moving blade of a gas turbine shown as a modified example of the present invention.
FIG. 5 is a partially enlarged sectional view of a moving blade of a gas turbine shown as a modified example of the present invention.
FIG. 6 is a longitudinal sectional view of a moving blade of a designated gas turbine according to another embodiment of the present invention.
FIG. 7 is a partially enlarged sectional view of a moving blade of a gas turbine shown as a modified example of the present invention.
8 is a cross-sectional view taken along the line AA in FIG.
FIG. 9 is a longitudinal sectional view showing a moving blade of a conventional gas turbine.
10 is a cross-sectional view taken along line EE in FIG.
FIG. 11 is an enlarged view of a U-turn portion in a conventional gas turbine.
[Explanation of symbols]
35 Serpentine cooling flow path 36a-36f Partition body 45, 65 Expansion diameter part 55-57 U-turn part

Claims (5)

In the blade body of a gas turbine having a serpentine cooling channel inside,
The serpentine flow path is divided by one or more partitions and is a meandering flow path,
The end of one or more of the partitions that form the meandering flow path is provided with an expanded portion that swells in the U-turn direction of the flow, and the end of the partition that has the expanded portion Is a turbine blade body characterized in that a recess is formed at an end portion in the flow path width direction . The turbine blade body according to claim 1,
A turbine blade body, wherein a hollow portion or a concave portion is provided in the expanded diameter portion. The turbine blade body according to claim 1 or 2,
The turbine blade body according to claim 1, wherein a flow path cross-sectional area of the U-turn portion formed by the expanded diameter portion is narrower on the upstream side than on the downstream side. In the turbine blade body according to any one of claims 1 to 3,
The turbine blade body characterized in that the expanded diameter portion and the partition are smoothly connected, and a sudden change in the flow path cross-sectional area upstream of the expanded diameter portion is mitigated. A gas turbine comprising the turbine blade body according to any one of claims 1 to 4 .

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