gas turbine engine

Abstract

To provide a gas turbine engine capable of removing foreign particles mixed in air for cooling a turbine.SOLUTION: A gas turbine engine (1) is provided with: a cooling air supply passage (41) for supplying air from a compressor (3) to a turbine (7) as a cooling medium while swirling in a circumferential direction, and including an introduction portion (41a) to which the air is introduced and a swirling portion (41b) for deflecting the air flowing in the introduction portion (41a) in the circumferential direction; and a chamber (45) branched from the swirling portion (41b) for capturing foreign particles (P) in the air, and formed to satisfy a relation of α≥β, when an angle of the swirling portion (41b) to a horizontal direction in a radial view is α, and an angle between the chamber (45) and the swirling portion (41b) is β.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to gas turbine engines. [Background technology]

[0002] The turbine of a gas turbine engine is driven by a supply of combustion gas generated in a combustor and is therefore exposed to extremely high temperatures. For this reason, it has been proposed to use air from the compressor as a cooling medium to cool the components that make up the turbine, for example by providing cooling passages in the turbine rotor blades (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-196356 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when the clearance between the compressor rotor blades and the housing is reduced to improve the efficiency of gas turbine engines, foreign particles may be generated due to rubbing between components. If such foreign particles generated upstream of the passage that supplies cooling air in the gas turbine engine (for example, in the compressor) are left unattended, the accumulation of foreign particles may clog the passage for cooling air, and the turbine may not be sufficiently cooled.

[0005] Therefore, an object of the present disclosure is to provide a gas turbine engine capable of removing foreign particles mixed in turbine cooling air in order to solve the above-mentioned problems. [Means for solving the problem]

[0006] In order to achieve the above object, a gas turbine engine according to the present disclosure comprises: a compressor that compresses air taken in from the outside; a combustor that burns a mixture of air compressed by the compressor and fuel; a turbine driven by combustion gas produced in the combustor; a cooling air supply passage that supplies air from the compressor as a cooling medium to the turbine while swirling the air in a circumferential direction, an introduction section into which the air is introduced; a swirl section that deflects the air flowing through the introduction section in a circumferential direction; a cooling air supply passage including: a chamber branched from the swirl portion for capturing foreign particles in the air, the chamber being formed so as to satisfy the relationship α≧β, where α is an angle formed by the swirl portion with respect to the horizontal direction as viewed in the radial direction, and β is an angle formed between the chamber and the swirl portion; It is equipped with: [Effects of the Invention]

[0007] According to the gas turbine engine of the present disclosure, it is possible to remove foreign particles that have become mixed in the turbine cooling air. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a partially cutaway side view illustrating a schematic configuration of a gas turbine engine according to an embodiment of the present disclosure; [Figure 2] 2 is an enlarged longitudinal cross-sectional view showing the surrounding area of ​​a cooling air supply passage of the gas turbine engine of FIG. 1. FIG. [Figure 3] FIG. 2 is a front view showing a cooling air supply passage of the gas turbine engine of FIG. 1. [Figure 4] 4 is a cross-sectional view taken along line IV-IV in FIG. 3, showing a schematic configuration of a cooling air supply passage and a chamber of the gas turbine engine in FIG. 1. [Figure 5A] 2 is a cross-sectional view showing the gas turbine engine of FIG. 1 in a state where a cooling air supply passage faces downward. [Figure 5B]2 is a cross-sectional view showing the gas turbine engine of FIG. 1 in a state where a cooling air supply passage faces upward. [Figure 6] 2 is an enlarged longitudinal cross-sectional view showing the surrounding area of ​​a cooling air supply passage of the gas turbine engine of FIG. 1. FIG. [Figure 7] 2 is a cross-sectional view showing a filter and a flow adjustment mechanism used in a chamber of the gas turbine engine of FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0009] A preferred embodiment of the present disclosure will now be described with reference to the drawings. Fig. 1 shows a gas turbine engine (hereinafter simply referred to as "gas turbine") 1 according to one embodiment of the present disclosure. In the gas turbine 1, air A taken in from the outside is compressed by a compressor 3 and introduced into a combustor 5. A mixture of this compressed air A and fuel F is combusted in the combustor 5, and a turbine 7 is driven by the generated high-temperature, high-pressure combustion gas BG.

[0010] In the following description, the compressor 3 side in the axial direction of the gas turbine 1 is referred to as the "front side," and the turbine 7 side is referred to as the "rear side." Furthermore, in the following description, unless otherwise specified, the terms "axial direction," "radial direction," and "circumferential direction" refer to the axial direction, radial direction, and circumferential direction of the gas turbine 1, respectively.

[0011] In this embodiment, an axial flow type compressor is used as the compressor 3. The compressor 3 includes a plurality of compressor rotor blades 11 implanted on the outer peripheral surface of a compressor rotor 9 and a plurality of compressor stator vanes 15 arranged on the inner peripheral surface of a compressor housing 13. The compressor 3 compresses air taken in through an intake cylinder 17 by a combination of these rotor blades 11 and stator vanes 15. A diffuser 19 is arranged downstream of the compressor 3. Compressed air A compressed by the compressor 3 is discharged from the diffuser 19 and supplied to the combustor 5.

[0012] The combustor 5 mixes fuel F with compressed air A delivered from the compressor 3 and burns the mixture to generate high-temperature, high-pressure combustion gas BG. The combustion gas BG generated in the combustor 5 flows into the turbine 7 through turbine stator blades 21 (first-stage turbine stator blades).

[0013] The turbine 7 includes a turbine rotor 23 and a turbine casing 25 that covers the turbine rotor 23. A plurality of turbine stator vanes 27 are attached at predetermined intervals to the inner periphery of the turbine casing 25. Meanwhile, a plurality of turbine moving blades 29 are provided on the outer periphery of the turbine rotor 23 so as to be located downstream of the turbine stator vanes 27 of each stage.

[0014] As shown in Fig. 2, the turbine rotor blades 29 are implanted on the outer periphery of a rotor disk 31 that is provided on the outer periphery of the turbine rotor 23. In this example, the turbine rotor blades 29 are provided with a mechanism for cooling the turbine rotor blades 29. Specifically, the turbine rotor blades 29 are provided with intra-turbine rotor blade cooling passages 33 for cooling the interior of the turbine rotor blades 29 with cooling air CA, and film cooling holes 35 for film cooling the outer wall surfaces of the aft ends of the turbine rotor blades 29 using air from the intra-turbine rotor blade cooling passages 33. The rotor disk 31 is provided with cooling air guide passages 37 for guiding the air for cooling the turbine rotor blades 29 to the intra-turbine rotor blade cooling passages 33.

[0015] In this embodiment, a cooling air supply passage 41 is provided that supplies air from the compressor 3 (FIG. 1) as a cooling medium (cooling air CA) to the turbine 7 while swirling it in the circumferential direction. As shown in FIG. 3, a plurality of cooling air supply passages 41 are arranged side by side in the circumferential direction Q. In the example shown in FIG. 2, the cooling air CA is supplied from the cooling air supply passage 41 to the cooling air guide passage 37 of the rotor disk 31. However, the cooling structure of the turbine 7 is not limited to the example shown in the figure, and the cooling air CA from the cooling air supply passage 41 may be supplied to an appropriate location depending on the cooling structure of the turbine 7.

[0016] Specifically, in this embodiment, the cooling air supply passage 41 is provided in a pre-swirl nozzle member 43. The pre-swirl nozzle member 43 is a ring-shaped block body, and is formed with a plurality of cooling air supply holes that form the cooling air supply passage 41. In the example shown, the pre-swirl nozzle member 43 is provided at an axial position rearward of the diffuser 19 and forward of the rotor disk 31. In this example, the pre-swirl nozzle member 43 is also arranged radially inward of the turbine stator vane 21.

[0017] As shown in FIG. 4, each cooling air supply passage 41 has an introduction section 41a that forms an inlet 41aa for the cooling air CA into the cooling air supply passage 41, and a swirling section 41b that deflects the cooling air CA flowing through the introduction section 41a in the circumferential direction. In the illustrated example, the introduction section 41a is formed as a passage that is slightly inclined in the circumferential direction Q with respect to the axial direction C. The swirling section 41b is formed as a passage that is deflected from the introduction direction I of the introduction section 41a in the circumferential direction Q by an angle θ1 (hereinafter, this angle will be referred to as the "first deflection angle"). Here, the "introduction direction I" refers to the mainstream direction of the cooling air CA at the inlet 41aa of the cooling air supply passage. Note that the first deflection angle θ1 is smaller than 90°. A plurality of cooling air supply passages 41 having this structure are arranged side by side in the circumferential direction Q as shown in FIG. 3, and the cooling air CA is supplied to the turbine 7 side shown in FIG. 2 as a swirling flow in the circumferential direction Q. In this embodiment, the swirling portion 41 b of the cooling air supply passage 41 is formed as a passage that is deflected from the axial direction C outward in the radial direction R in a direction that substantially corresponds to the cooling air guide passage 37 of the rotor disk 31 .

[0018] 4, the gas turbine 1 according to this embodiment is further provided with a chamber 45 that captures foreign particles P in the cooling air CA. The chamber 45 is provided branching off from the swirl section 41b of the cooling air supply passage 41. Specifically, the chamber 45 branches off from an upstream portion of the swirl section 41b, i.e., a portion of the swirl section 41b close to the introduction section 41a.

[0019] The chamber 45 captures the foreign particles P in the cooling air CA by utilizing the difference in inertial force acting on the cooling air CA and the foreign particles P when the cooling air CA containing the foreign particles P is deflected from the inlet portion 41a to the swirling portion 41b. Specifically, the angle θ2 (hereinafter, this angle will be referred to as the "second deflection angle") formed between the flow direction of the inlet portion 41a of the cooling air supply passage 41 and the flow direction into the chamber 45 is smaller than the first deflection angle θ1. In other words, in the illustrated example, the chamber 45 branches rearward from the swirling portion 41b. Therefore, when the cooling air CA is deflected from the inlet portion 41a to the swirling portion 41b, a larger inertial force acts on the foreign particles P in the cooling air CA due to the difference in specific gravity. As a result, the foreign particles P flow along the outer periphery of the swirling flow and enter the chamber 45. The foreign particles P that flow into the chamber 45 are trapped in the chamber 45 by adhering to the inner wall surface of the chamber 45 due to the swirling flow generated in the chamber 45 .

[0020] 5A, the chamber 45 is formed so as to satisfy the relationship α≧β, where α is the angle formed by the swirl portion 41b of the cooling air supply passage 41 with respect to the horizontal direction H when viewed in the radial direction R (hereinafter referred to as the "swirl portion angle" for convenience), and β is the angle formed between the chamber 45 and the swirl portion 41b (hereinafter referred to as the "chamber angle" for convenience). Note that when the introduction direction I (FIG. 4) coincides with the horizontal direction H, α=θ1.

[0021] By setting the swirl section angle α and the chamber angle β to satisfy the relationship α≧β, foreign particles P trapped in the chamber 45 are prevented from falling downstream of the cooling air supply passage 41, i.e., toward the turbine 7, where they cannot be retrapped, when the gas turbine 1 is stopped. Specifically, while the gas turbine 1 is stopped, gravity G is the only factor moving the foreign particles P. When the downstream end of the cooling air supply passage 41 faces downward as shown in FIG. 5A, α≧β prevents the foreign particles P from falling into the cooling air supply passage 41. When the downstream end of the cooling air supply passage 41 faces upward as shown in FIG. 5B, α≧β allows the foreign particles P to fall into the cooling air supply passage 41. However, because the foreign particles P fall upstream of the chamber 45 in the cooling air supply passage 41, they can be retrapped in the chamber 45 after the gas turbine 1 is restarted.

[0022] In the example shown in FIG. 4, a plurality of chambers 45 (three in this example) are provided on the rear wall surface of the swirl section 41b along the longitudinal direction of the swirl section 41b. As shown in FIG. 6, the plurality of chambers 45 are arranged such that all of the inlets 45a of all of the chambers 45 are located within a projection plane 47 of the passage cross section of the outlet 41ab of the introduction section 41a (the boundary between the introduction section 41a and the swirl section 41b) in the introduction direction I. Note that the "outlet 41ab of the introduction section 41a" refers to the point where the linear portion of the vertical cross section of the passage inner wall surface of the introduction section 41a terminates. While it is not essential to arrange the chambers 45 in this manner, it is preferable to arrange the chambers 45 such that at least a portion of the inlets 45a of the plurality of chambers 45 are located within a projection plane 47 of the passage cross section of the outlet 41ab of the introduction section 41a in the introduction direction I. This configuration can increase the capture rate of foreign particles P in the cooling air CA.

[0023] It is not essential to provide a plurality of chambers 45, and only one chamber 45 may be provided. In this case, too, the cross section of the passage of the outlet 41ab of the introduction part 41a Introduction direction IIt is preferable that at least a part of the inlet 45a of the chamber 45 is located within the projection plane 47 onto the chamber 45, and more preferable that the entire inlet 45a is located within the projection plane 47 onto the chamber 45.

[0024] In this embodiment, the chamber 45 is formed as a circular hole provided in the pre-swirl nozzle member 43 (FIG. 2). The chamber 45 may have a shape other than a circular hole, for example, the cross-sectional shape may be oval or rectangular, but by forming the chamber 45 as a circular hole, it becomes easier to form the chamber 45 in a block body such as the pre-swirl nozzle member 43. In addition, when the chamber 45 is formed as a circular hole, it is necessary to consider (i) the relationship between the diameter of the circular hole and the flow path width of the swirl section 41b, and (ii) the above-mentioned relationship between the inlet 45a of the chamber 45 and the cross-sectional shape of the passage at the outlet of the introduction section 41a. Introduction direction I and (iii) the maximum number of chambers 45 that can be arranged is preferably provided, taking into consideration the spacing between adjacent chambers 45.

[0025] 6, an oval-hole-shaped chamber 45 may be provided that includes areas corresponding to the plurality of chambers 45. However, if the ratio of the area of ​​the inlet 45a of the chamber 45 to the length dimension of the chamber 45 (the depth dimension from the inlet 45a of the chamber 45) is large, the proportion of foreign particles P that once flow into the chamber 45 but are not captured in the chamber 45, swirl with the air, and flow out into the cooling air supply passage 41 increases. Therefore, from this perspective, it is preferable to provide a large number of chambers 45 with smaller inlet areas rather than a small number of chambers 45 with large inlet areas.

[0026] 7, in this embodiment, a filter 51 is provided in the chamber 45 to capture foreign particles P that have flowed into the chamber 45 and allow cooling air CA to pass through. The filter 51 is detachably provided in the chamber 45. Specifically, a lid 53 with a filter is fitted to the downstream end of the chamber 45. Any filter may be used as the filter 51 as long as it can accommodate the expected particle size of the foreign particles P (for example, approximately several tens to 100 μm).

[0027] In addition, a flow rate adjustment mechanism 55 that adjusts the flow rate of cooling air CA discharged from the chamber 45 is provided at the downstream end of the chamber 45. In this example, a filter 51 is attached to the upstream end of the lid 53, and an orifice is provided as the flow rate adjustment mechanism 55 at the portion of the lid 53 downstream of the filter 51.

[0028] By providing the filter 51 in the chamber 45, it becomes possible to capture the foreign particles P more efficiently. Furthermore, by providing the filter 51 in a detachable manner in the chamber 45, it becomes easier to replace and maintain the filter 51. Even if the filter 51 is not provided in the chamber 45, it is preferable to cover the downstream end of the chamber 45 with a detachable lid 53. This makes it easier to perform maintenance work inside the chamber 45.

[0029] Incidentally, even when filter 51 is provided on lid 53, it is not essential to provide flow rate adjustment mechanism 55 downstream thereof, and an air outlet (for example, a communication hole to the outside of chamber 45) through which air can flow out from the downstream side of chamber 45 may be provided. By providing such an air outlet, a negative pressure can be created inside chamber 45, thereby acting to retain foreign particles P within chamber 45. However, providing flow rate adjustment mechanism 55 makes it easier to set an appropriate flow rate for achieving efficient capture of foreign particles P, that is, to set a flow rate that can effectively capture foreign particles P while compensating for a decrease in flow rate in cooling air supply passage 41 caused by providing chamber 45 with flow rate adjustment mechanism 55.

[0030] 2, the swirl portion 41b of the cooling air supply passage 41 provided in the pre-swirl nozzle member 43 is formed as a passage that is deflected from the axial direction C outward in the radial direction R in a direction that generally corresponds to the cooling air guide passage 37 of the rotor disk 31. However, the configuration of the cooling air supply passage 41 provided in the pre-swirl nozzle member 43 is not limited to this example. For example, the swirl portion 41b of the cooling air supply passage 41 provided in the pre-swirl nozzle member 43 may extend linearly without being deflected in the radial direction R, or may be deflected inward in the radial direction R.

[0031] In addition, in this embodiment, an example has been described in which the cooling air supply passage 41 is provided in the pre-swirl nozzle member 43, but it is not essential to use the pre-swirl nozzle member 43. For example, the cooling air supply passage 41 may be formed by a swirler having a plurality of swirl vanes.

[0032] Furthermore, in this embodiment, an example has been described in which the air discharged from the diffuser 19 provided downstream of the compressor 3 is used as the cooling air CA, but air from another part inside the gas turbine 1 may also be used as the cooling air CA. For example, air extracted from an intermediate stage of the compressor 3 may also be used as the cooling air CA.

[0033] As described above, according to the gas turbine 1 of this embodiment, the foreign particles P in the cooling air CA can be captured in the chamber 45 by utilizing the inertial force acting on the foreign particles P. Furthermore, since the chamber 45 is formed so that the swirl angle α is equal to or greater than the chamber angle β, the foreign particles P captured in the chamber 45 are prevented from falling toward the turbine 7 even when the gas turbine 1 is stopped. Therefore, it is possible to effectively remove the foreign particles P mixed in the cooling air CA of the turbine 7.

[0034] This embodiment may further include a pre-swirl nozzle member 43 having a ring-shaped block body formed with a plurality of cooling air supply holes that form the cooling air supply passage 41, and the chamber 45 may be formed in the pre-swirl nozzle member 43. In this case, for example, the chamber 45 may be provided as a circular hole formed in the pre-swirl nozzle member 43. With this configuration, the cooling air supply passage 41 and the chamber 45 having the above-described structure can be formed easily and at low cost.

[0035] In this embodiment, the chamber 45 may be provided with a filter 51 that captures foreign particles P that have flowed into the chamber 45 and allows air to pass through. This configuration makes it possible to capture foreign particles P with higher efficiency.

[0036] In this embodiment, the filter 51 may be provided detachably with respect to the chamber 45. This configuration makes it easy to replace and maintain the filter 51.

[0037] In this embodiment, the chamber 45 may be provided with a flow rate adjustment mechanism 55 that adjusts the flow rate of air discharged from the chamber 45. This configuration facilitates setting an appropriate flow rate to achieve efficient capture of the foreign particles P, that is, setting a flow rate that can effectively capture the foreign particles P while compensating for a decrease in the flow rate in the cooling air supply passage 41 caused by providing the chamber 45 with the flow rate adjustment mechanism 55.

[0038] As described above, the preferred embodiments of the present disclosure have been described with reference to the drawings, but various additions, modifications, and deletions can be made without departing from the spirit of the present disclosure. Therefore, such additions, modifications, and deletions are also included in the scope of the present disclosure. [Explanation of symbols]

[0039] 1. Gas turbine engine 3. Compressor 5. Combustor 7 Turbine 41 Cooling air supply passage 41a Introduction 41b Swivel part 45 Chamber 51 filters 55 Flow rate adjustment mechanism P Foreign particles

Claims

1. a compressor that compresses air taken in from the outside; a combustor that burns a mixture of air compressed by the compressor and fuel; a turbine driven by combustion gas produced in the combustor; a cooling air supply passage that supplies air from the compressor as a cooling medium to the turbine while swirling the air in a circumferential direction around an axial direction of the gas turbine engine, an introduction section into which air from the compressor is introduced; a swirl section that deflects the air flowing through the introduction section in the circumferential direction; a cooling air supply passage including: a chamber branched from the swirl portion for capturing foreign particles in the air, the chamber being formed so as to satisfy the relationship α≧β, where α is an angle formed by the swirl portion with respect to the horizontal direction as viewed in the radial direction, and β is an angle formed between the chamber and the swirl portion; A gas turbine engine comprising:

2. 2. The gas turbine engine of claim 1, a pre-swirl nozzle member having a ring-shaped block body formed with a plurality of cooling air supply holes that form the cooling air supply passage; the chamber is formed in the pre-swirl nozzle member; The chamber is provided as a circular hole formed in the pre-swirl nozzle member. Gas turbine engine.

3. 3. The gas turbine engine according to claim 1, The chamber is provided with a filter that captures foreign particles that flow into the chamber and allows air to pass through. Gas turbine engine.

4. 4. The gas turbine engine of claim 3, The filter is detachably provided in the chamber. Gas turbine engine.

5. 5. A gas turbine engine according to claim 1, a flow rate adjusting mechanism for adjusting the flow rate of air discharged from the chamber is provided at the downstream end of the chamber; Gas turbine engine.

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