Gas turbine scroll

Abstract

To provide a scroll of a gas turbine that comprises a deformation suppression member to suppress deformation of an outlet of a scroll over a circumferential direction, and can replace the deformation suppression member easily.SOLUTION: A scroll 40A causes combustion gas 27 discharged from a combustor 20 to flow in an axial direction and circumferential direction of a turbine rotor 33, and guides it to a turbine. The scroll 40A comprises: an outer peripheral wall 50; an inner peripheral wall 60 that forms an annular passage 70 with the outer peripheral wall 50, and is provided on the turbine rotor side of the outer peripheral wall 50 with a gap from the outer peripheral wall 50; and a plurality of deformation suppression members 80 that is provided in the circumferential direction of an outlet part of the scroll 40A, penetrates the outer peripheral wall 50 and the inner peripheral wall 60 in a radial direction, and has one end removably fixed to the outer peripheral wall 50 and the other end removably fixed to the inner peripheral wall 60.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] Embodiments of the present invention relate to a scroll of a gas turbine.

Background Art

[0002] Conventionally, gas turbines equipped with single-can combustors or silo-type combustors have been widespread. These combustors are arranged in a direction perpendicular to the axial direction of the turbine rotor. Therefore, the gas turbine includes a scroll that redirects the combustion gas discharged from the combustor in the axial direction of the turbine rotor and guides it in the circumferential direction of the turbine rotor.

[0003] The scroll forms an annular passage extending in the axial direction of the turbine rotor around the turbine rotor. The annular passage is formed between an outer peripheral wall and an inner peripheral wall. Then, the combustion gas passes through the annular passage and is guided from the outlet of the scroll to the first-stage stationary blades (nozzles).

[0004] At the outlet of the scroll, in order to eject the combustion gas at a uniform speed across the circumferential direction, the gap between the outer peripheral wall and the inner peripheral wall is set to have a predetermined width across the circumferential direction. Also, the size and shape of the outlet of the scroll are set corresponding to the size and shape of the inlet of the first-stage stationary blades.

[0005] Around the scroll, a cooling medium such as compressed air for cooling the scroll from the outside flows. That is, high-temperature combustion gas flows in the annular passage inside the scroll, and a cooling medium cooler than the temperature of the combustion gas flows on the outer periphery of the scroll.

[0006] Also, the pressure of the cooling medium is set higher than the pressure of the combustion gas so that a part of the cooling medium can be introduced into the combustor liner of the combustor. That is, the pressure of the cooling medium flowing on the outer periphery of the scroll is higher than the pressure of the combustion gas flowing in the annular passage inside the scroll.

Prior Art Documents

Patent Documents

[0007] [Patent Document 1] Japanese Patent Application Publication No. 1-155120 [Overview of the project] [Problems that the invention aims to solve]

[0008] As described above, a pressure difference (internal-external pressure difference) arises between the pressure of the combustion gas flowing through the annular passage within the scroll and the pressure of the cooling medium flowing around the outer circumference of the scroll. Therefore, the scroll is subjected to a force due to this internal-external pressure difference. This internal-external pressure difference increases further as the pressure of the gas turbine increases.

[0009] At the scroll outlet, which is the open end, deformation can occur due to the pressure difference between the inside and outside. In a scroll, the outer circumferential wall is more susceptible to deformation due to the pressure difference than the inner circumferential wall. For example, the pressure difference can cause the outer circumferential wall in the horizontal direction to deform towards the central axis of the turbine rotor (inward), and the outer circumferential wall in the vertical direction to deform away from the central axis of the turbine rotor (outward). This changes the size and shape of the scroll outlet, making it difficult to properly eject combustion gases to the first stage stator vanes.

[0010] Furthermore, if the thickness of the outer wall of the scroll is increased to enhance its rigidity, a problem arises in which thermal stress is generated in the outer wall due to the temperature difference between the combustion gas and the cooling medium.

[0011] Furthermore, in conventional gas turbine transition pieces, a technique has been considered in which support columns are welded between the outer and inner walls forming a ring-shaped passage to suppress deformation at the outlet. However, if this technique is adopted, it is difficult to easily replace the support columns when they deteriorate.

[0012] The problem that this invention aims to solve is to provide a gas turbine scroll that suppresses deformation of the scroll outlet over the circumferential direction by incorporating a deformation suppression member, and that allows the deformation suppression member to be easily replaced. [Means for solving the problem]

[0013] The scroll of the gas turbine in this embodiment guides the combustion gas discharged from the combustor to the turbine by causing it to flow in the axial direction and circumferential direction of the turbine rotor. The scroll of the gas turbine comprises an outer peripheral wall, an inner peripheral wall that forms an annular passage with the outer peripheral wall and is provided on the turbine rotor side of the outer peripheral wall with a predetermined gap between it and the outer peripheral wall, and a plurality of deformation suppressing members provided in the circumferential direction of the outlet portion of the scroll, penetrating the outer peripheral wall and the inner peripheral wall in the radial direction of the turbine rotor, with one end detachably fixed to the outer peripheral wall and the other end detachably fixed to the inner peripheral wall. Each of the deformation-suppressing members is fastened to the outer and inner walls by bolts or nuts. [Brief explanation of the drawing]

[0014] [Figure 1] This figure shows a longitudinal cross-section of a gas turbine equipped with a scroll according to the first embodiment. [Figure 2] This is a diagram showing cross-section AA in Figure 1. [Figure 3] This figure shows an enlarged view of the radial cross-section of the exit portion of the scroll in the first embodiment. [Figure 4] This is a plan view of the fixed seat portion of the exit portion of the scroll in the first embodiment, as seen from the radially outer side. [Figure 5] This is a plan view of the scroll deformation suppression member according to the first embodiment. [Figure 6] Figure 5 shows a cross-section of BB. [Figure 7] Figure 5 shows a cross-section of CC. [Figure 8] This is a diagram showing the DD cross-section, as shown in Figure 5. [Figure 9] This figure shows an enlarged view of the radial cross-section of the exit portion of the scroll in the second embodiment. [Figure 10] This is a plan view of the scroll deformation suppression member according to the second embodiment. [Figure 11]It is a figure showing a longitudinal section of a scroll deformation suppressing member according to a second embodiment. [Figure 12] It is a figure showing an E-E cross section of FIG. 10. [Figure 13] It is a figure showing an F-F cross section of FIG. 11. [Figure 14] It is a figure showing a G-G cross section of FIG. 11.

Mode for Carrying Out the Invention

[0015] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0016] (First Embodiment) FIG. 1 is a longitudinal sectional view showing a gas turbine 1 provided with a scroll 40A according to a first embodiment. FIG. 2 is a view showing an A-A cross section of FIG. 1. In FIG. 1, the upper half configuration is shown, and in FIG. 2, the upper half and lower half configurations are shown. Here, an example in which the combustor 20 is provided in the upper half is shown.

[0017] As shown in FIGS. 1 and 2, the gas turbine 1 includes a compressor 10, a combustor 20, a turbine 30, and a scroll 40A.

[0018] The compressor 10 compresses, for example, the intake air to generate compressed air 11.

[0019] The combustor 20 supplies fuel to the compressed air 11 and burns it to generate high-temperature combustion gas 27. As shown in FIG. 1, the combustor 20 is, for example, composed of a single-can combustor. The combustor 2 is, for example, disposed above the gas turbine 1 and extends in the vertical direction, in other words, in a direction perpendicular to the central axis O of the turbine rotor 33 of the turbine 30.

[0020] Although a single-can combustor is used as an example in this explanation, the combustor is not limited to this. Other combustors, such as silo-type combustors, can also be applied. In other words, any combustor that requires a scroll to flow the combustion gas discharged from the combustor liner in the axial direction and circumferential direction of the turbine rotor 33 is included in the combustors of this embodiment.

[0021] Hereafter, the axial direction of the turbine rotor 33 will be simply referred to as the axial direction. Also, the circumferential direction of the turbine rotor 33 will be simply referred to as the circumferential direction.

[0022] The combustor 20 includes a combustor liner 21 for burning fuel and compressed air 11, a fuel nozzle 22 for supplying fuel into the combustor liner 21, and an oxidant supply unit 23 for supplying compressed air 11 as an oxidant into the combustor liner 21.

[0023] Here, we show an example using air taken in by the compressor 10 as the oxidizer, but the oxidizer is not limited to air. For example, oxygen or a mixture of oxygen and water vapor may be used as the oxidizer. When oxygen or a mixture of oxygen and water vapor is used as the oxidizer, the oxygen is supplied to the oxidizer supply unit 23 from a separate external system, rather than from the compressor 10. In this case, water vapor may be supplied from the compressor 10. The water vapor can function as a diluent or cooling medium, as described later. Also, when a mixture of oxygen and water vapor is used as the oxidizer, the oxidizer supply unit 23 may be configured to introduce water vapor supplied from the compressor 10.

[0024] Alternatively, a mixture of oxygen and carbon dioxide may be used as the oxidizing agent. This mixture of oxygen and carbon dioxide is supplied to the oxidizing agent supply unit 23 from a separate external system. In this case, for example, carbon dioxide can be introduced into the combustor casing 24 and casing 5 to function as a diluent or cooling medium. In this case, the compressor 10 becomes unnecessary.

[0025] The fuel is not particularly limited. Examples of fuels used include hydrocarbons such as methane and natural gas, hydrogen, ammonia, hydrocarbon-hydrogen composite fuels, and hydrocarbon-ammonia composite fuels. Additionally, coal gasification fuels containing carbon monoxide and hydrogen can be used. Coal gasification fuels containing ammonia can also be used.

[0026] The combustor liner 21 is composed of a cylindrical body extending perpendicular to the central axis O. The combustor liner 21 has a plurality of inlet holes 21a formed therein for introducing compressed air 11 into the combustor liner 21, for example. The compressed air 11 introduced through the inlet holes 21a functions, for example, as a diluent for the combustion gas. The oxidizer supply unit 23 is arranged, for example, around the fuel nozzle 22.

[0027] The combustor 20 is covered by a combustor casing 24. One end of the combustor casing 24 is connected to the casing 5 of the gas turbine 1. The other end of the combustor casing 24 is sealed with a flat plate-shaped cover member 25.

[0028] The fuel supply pipe 26, which supplies fuel to the fuel nozzle 22, is routed, for example, through the cover member 25. The compressed air 11 is guided to the combustor 20 by the guide member 12 and spreads within the space inside the combustor casing 24 and casing 5.

[0029] The scroll 40A is positioned between the combustor liner 21 and the turbine 30. One end (inlet) of the scroll 40A is connected to the outlet end of the combustor liner 21. The other end (outlet) of the scroll 40A is positioned opposite the stator vanes 31 of the first stage of the turbine 30. The configuration of the scroll 40A will be explained in detail later.

[0030] Here, the turbine 30 includes a turbine rotor 33 on which rotor blades 32 are arranged in the circumferential direction. The turbine 30 has multiple stages in the axial direction of rotor blade rows, which are formed by arranging multiple rotor blades 32 in the circumferential direction.

[0031] The turbine 30 has multiple stages of stator blade rows arranged axially on the inner circumference of the casing 5, each consisting of multiple stator blades 31 arranged circumferentially. The stator blade rows are arranged alternately with the rotor blade rows in the axial direction. A single turbine stage is formed by a stator blade row and the rotor blade row immediately downstream of it. The turbine 30 has multiple turbine stages within the casing 5.

[0032] Next, we will explain the configuration of Scroll 40A in detail.

[0033] Figure 3 is an enlarged view of the radial cross-section of the outlet portion of the scroll 40A in the first embodiment. Note that the deformation suppression member 80 is not shown in the cross-sectional view in Figure 3. Figure 4 is a plan view of the fixed seat portion 52 of the outlet portion of the scroll 40A in the first embodiment, viewed from the radially outer side. Figure 5 is a plan view of the deformation suppression member 80 of the scroll 40A in the first embodiment. Figure 6 is a view of the BB cross-section of Figure 5. Figure 7 is a view of the CC cross-section of Figure 5. Figure 8 is a view of the DD cross-section of Figure 5.

[0034] The scroll 40A guides the combustion gas 27 discharged from the combustor liner 21 of the combustor 20 to the turbine by causing it to flow in the axial and circumferential directions.

[0035] The scroll 40A comprises an outer peripheral wall 50, an inner peripheral wall 60 provided on the turbine rotor 33 side of the outer peripheral wall 50, and a deformation suppression member 80. In other words, the inner peripheral wall 60 is positioned radially inward from the turbine rotor 33 than the outer peripheral wall 50. The inner peripheral wall 60 is provided with a predetermined gap between it and the outer peripheral wall 50.

[0036] Here, the radial direction of the turbine rotor 33 is perpendicular to the central axis O. Hereafter, the radial direction of the turbine rotor 33 will be simply referred to as the radial direction. The inner side of the radial direction means the side that approaches the central axis O in the radial direction. Hereafter, the inner side of the radial direction will be referred to as the inner radial direction. The outer side of the radial direction means the side that moves away from the central axis O in the radial direction. Hereafter, the outer radial direction will be referred to as the outer radial direction.

[0037] As shown in Figures 1 and 2, the scroll 40A includes a bent flow path section 41 that guides the combustion gas 27 discharged from the combustor liner 21 in the axial direction, and an annular flow path section 42 that guides the combustion gas 27 guided in the axial direction in the circumferential direction.

[0038] The upstream end of the bent flow path section 41 is connected to the downstream end of the combustor liner 21. The bent flow path section 41 forms a curved flow path that bends approximately 90 degrees in the axial direction. The outlet side of the bent flow path section 41 has a configuration that widens circumferentially while bending. That is, in the bent flow path section 41, the flow of combustion gas is also widened circumferentially.

[0039] The bent flow path section 41 then deflects the flow of combustion gas 27 discharged from the combustor liner 21 by approximately 90 degrees. The deflected flow of combustion gas 27 then flows in the axial direction.

[0040] The annular flow channel section 42 constitutes an annular passage 70 provided to cover the periphery of the turbine rotor 33. Specifically, the annular flow channel section 42 formed on the outlet 43 side of the scroll 40A includes an annular passage 70 formed between the inner circumferential wall 60 and the outer circumferential wall 50, extending over the entire circumference of the turbine rotor 33.

[0041] The annular flow channel 42 spreads the flow of combustion gas 27 discharged from the bent flow channel 41 in the circumferential direction. In the annular flow channel 42, the combustion gas 27 having an axial velocity component spreads uniformly in the circumferential direction.

[0042] The outlet 43 of the annular flow channel 42 (scroll 40A) faces the first-stage stator vane 31. The combustion gas 27 flowing through the annular flow channel 42 is ejected from the outlet 43 toward the first-stage stator vane 31.

[0043] As shown in Figures 1-3, multiple deformation suppressing members 80 are provided in the circumferential direction of the outlet portion of the scroll 40A (annular flow channel portion 42). In other words, multiple deformation suppressing members 80 are provided in the circumferential direction of the scroll 40A near the outlet 43. The deformation suppressing members 80 are provided, for example, at equal intervals in the circumferential direction.

[0044] The deformation-retaining member 80 penetrates radially through the outer circumferential wall 50 and the inner circumferential wall 60 that constitute the annular flow channel 42. One end of the deformation-retaining member 80 is detachably fixed to the outer circumferential wall 50. The other end of the deformation-retaining member 80 is detachably fixed to the inner circumferential wall 60. As shown in Figure 3, the deformation-retaining member 80 is detachably fastened to the outer circumferential wall 50 and the inner circumferential wall 60 by bolts 93 or nuts 111.

[0045] As shown in Figures 3 and 4, a fixing seat portion 52 for fixing one end of the deformation suppressing member 80 is formed on the radially outer circumferential surface 51 of the outer circumferential wall 50. Also, as shown in Figure 3, a fixing seat portion 62 for fixing the other end of the deformation suppressing member 80 is formed on the radially inner circumferential surface 61 of the inner circumferential wall 60. The fixing seat portion 52 functions as a first fixing seat portion, and the fixing seat portion 62 functions as a second fixing seat portion.

[0046] The fixing seat portion 52 protrudes radially outward from the outer peripheral surface 51. The radially outer end face 53 of the fixing seat portion 52 is flat. The fixing seat portion 52 has screw holes 54 for fixing the fixing flange portion 90 of the deformation suppression member 80, which will be described later.

[0047] Furthermore, the fixed seat portion 52 and the outer peripheral wall 50 have insertion holes 55 formed therein for inserting and passing through the main body portion 100 and the fixing screw portion 110 of the deformation suppression member 80, which will be described later. The shape of these insertion holes 55 is set, for example, to correspond to the shape of the main body portion 100. That is, as shown in Figure 4, the fixed seat portion 52 is an annular protruding structure having an insertion hole 55 in the center.

[0048] The fixed seat portion 62 protrudes radially inward from the inner circumferential surface 61. The radially inner end face 63 of the fixed seat portion 62 is flat. As shown in Figure 3, the nut 111 abuts against the end face 63.

[0049] The fixed seat portion 62 and the inner circumferential wall 60 have through holes 64 formed therein for the fixing screw portion 110 of the deformation suppressing member 80, which will be described later, to pass through. The diameter of these through holes 64 is set to correspond to the outer diameter of the fixing screw portion 110. In other words, the fixed seat portion 62 is an annular protruding structure having a through hole 64 in the center.

[0050] As shown in Figure 5, the deformation-suppressing member 80 comprises a fixed flange portion 90, a main body portion 100, and a fixed screw portion 110. The fixed flange portion 90, the main body portion 100, and the fixed screw portion 110 may be formed integrally. Alternatively, the deformation-suppressing member 80 may be constructed by joining together the fixed flange portion 90, the main body portion 100, and the fixed screw portion 110, which are each formed separately.

[0051] As shown in Figures 5 and 6, the fixing flange portion 90 is composed of, for example, a circular flat plate-shaped member. The outer edge of the back surface 91 (the surface on the main body portion 100 side) of the fixing flange portion 90 abuts against the end surface 53 of the fixing seat portion 52. Therefore, the back surface 91 of the fixing flange portion 90 is composed of a flat surface, similar to the end surface 63.

[0052] As shown in Figure 6, the fixing flange portion 90 has a through hole 92 for passing a bolt 93 through which the fixing flange portion 90 is fixed to the fixing seat portion 52. The through hole 92 is formed at a position corresponding to the screw hole 54 formed in the fixing seat portion 52. The fixing flange portion 90 also has an introduction hole 94 for introducing a cooling medium into the introduction passage 103 of the main body portion 100. This introduction hole 94 is formed at a position corresponding to the introduction passage 103 so as to communicate with the introduction passage 103 of the main body portion 100.

[0053] The fixed flange portion 90 is detachably fastened to the fixed seat portion 52 from the radially outer side by bolts 93. That is, the radially outer end of the deformation suppressing member 80 is detachably fastened to the outer surface 51 (fixed seat portion 52) of the outer peripheral wall 50 from the radially outer side by bolts 93.

[0054] The main body portion 100 is composed of a column extending from the back surface 91 of the fixed flange portion 90 in a direction perpendicular to the back surface 91. When the deformation suppression member 80 is fixed to the scroll 40A, as shown in Figure 3, the main body portion 100 extending radially inward from the back surface 91 of the fixed flange portion 90 penetrates the outer peripheral wall 50, and the tip surface 101 of the main body portion 100 abuts against the radially outer outer peripheral surface 65 of the inner peripheral wall 60.

[0055] The outer circumferential surface 65 has, for example, a recess 66 that is recessed radially inward. The bottom surface 67 of the recess 66 is flat, similar to the tip surface 101, in order to contact the tip surface 101 of the main body 100. A portion of the tip portion 102, including the tip surface 101, fits into the recess 66. The recess 66 supports and positions the tip portion 102 of the main body 100.

[0056] Here, the longitudinal length (radial length) of the main body 100 is set based on a predetermined gap distance between the outer circumferential wall 50 and the inner circumferential wall 60. That is, when the deformation suppressing member 80 is installed by bringing the tip surface 101 into contact with the bottom surface 67 of the recess 66, as shown in Figure 3, the longitudinal length (radial length) of the main body 100 is equal to the radial distance from the end surface 53 of the fixed seat portion 52 to the bottom surface 67 of the recess 66.

[0057] The main body 100 is composed of a columnar body such as a cylinder. Preferably, the main body 100 is composed of a columnar body with an elliptical cross-section perpendicular to the longitudinal direction, as shown in Figures 7 and 8. In this case, the main body 100 has a leading edge 105 positioned toward the upstream of the flow of combustion gas 27 and a trailing edge 106 positioned toward the downstream of the flow of combustion gas 27. That is, in the main body 100 shown in Figures 7 and 8, the combustion gas 27 flows from left to right. By making the shape of the main body 100 a streamlined shape such as an ellipse, the pressure loss in the flow of combustion gas 27 is reduced.

[0058] The main body 100 may be equipped with a cooling structure for cooling the main body 100, as shown in Figures 7 and 8. The cooling structure of the main body 100 may include, for example, an introduction passage 103 and an exhaust hole 104.

[0059] Here, compressed air 11 supplied from the compressor 10 into the casing 5 is used as a cooling medium to cool the main body 100. This compressed air 11 is present around the scroll 40A. The temperature of the compressed air 11 is lower than the temperature of the combustion gas 27 flowing through the annular passage 70. The compressed air 11 used to cool the main body 100 is referred to as the cooling medium.

[0060] The introduction passage 103 introduces the cooling medium into the main body 100 from the outside of the scroll 40A through the introduction hole 94 of the fixed flange portion 90. The introduction passage 103 is formed from the end of the main body 100 on the fixed flange portion 90 side toward the tip portion 102 of the main body 100. The introduction passage 103 is formed, for example, in the longitudinal direction (radial direction) of the main body 100. Note that the introduction passage 103 does not penetrate to the tip surface 101.

[0061] Multiple introduction passages 103 are formed in the main body 100. Preferably, the introduction passages 103 are formed on the outer peripheral edge close to the outer surface of the main body 100, as shown in Figures 7 and 8. This promotes cooling of the outer surface of the main body 100, which becomes hot.

[0062] Furthermore, by providing multiple introduction passages 103 and reducing the flow path cross-sectional area of ​​a single introduction passage 103, the flow velocity of the cooling medium flowing through the introduction passages 103 can be increased. This promotes heat transfer between the cooling medium and the walls of the introduction passages 103.

[0063] The discharge hole 104 discharges the cooling medium introduced into the introduction passage 103 to the outside. When the deformation suppression member 80 is fixed to the scroll 40A, the discharge hole 104 discharges the cooling medium into the annular passage 70.

[0064] As shown in Figure 8, one end of the discharge hole 104 communicates with the introduction passage 103. The other end of the discharge hole 104 penetrates the side of the tip portion 102 in the main body portion 100. Thus, the discharge hole 104 is composed of a through hole that communicates with the introduction passage 103. As shown in Figure 3, when the tip portion 102 is fitted into the recess 66, the discharge hole 104 is located radially outward from the outer peripheral surface 65.

[0065] Here, the discharge hole 104 should be configured to discharge the cooling medium introduced into the introduction passage 103 to the outside. Preferably, the discharge hole 104 is formed at an angle to the downstream side of the combustion gas 27 flow, as shown in Figure 8. By forming the discharge hole 104 at an angle to the downstream side, interference between the combustion gas 27 flow around the main body 100 and the cooling medium flow discharged from the discharge hole 104 can be suppressed. This reduces the pressure loss in the combustion gas 27 flow. In addition, by forming the discharge hole 104 at an angle to the downstream side, it is possible to prevent the combustion gas 27 from flowing into the discharge hole 104.

[0066] Here, the configuration of the introduction passage 103 and the discharge hole 104 as a cooling structure is not limited to the configuration described above. The introduction passage 103 only needs to be configured to allow the cooling medium to be introduced into the main body 100 in order to cool the main body 100. The discharge hole 104 only needs to be configured to allow the cooling medium introduced into the introduction passage 103 to be discharged to the outside (annular passage 70).

[0067] As shown in Figure 5, the fixing screw portion 110 is composed of a rod-shaped screw member extending from the tip surface 101 of the main body portion 100 in a direction perpendicular to the tip surface 101. When the deformation suppression member 80 is fixed to the scroll 40A, as shown in Figure 3, the fixing screw portion 110 extending radially inward from the tip surface 101 of the main body portion 100 penetrates the inner circumferential wall 60 and the fixing seat portion 62.

[0068] The side surface of the fixing screw portion 110 has a threaded surface 112 that engages with the nut 111. The fixing screw portion 110 is set to a length that allows it to be fixed to the fixing seat portion 62 by the nut 111.

[0069] The fixing screw portion 110 is then detachably fastened to the fixing seat portion 62 by a nut 111. In other words, the radially inner end of the deformation suppressing member 80 is detachably fastened from the radially inner side to the inner surface 61 (fixing seat portion 62) of the inner circumferential wall 60 by a nut 111.

[0070] When fixing the deformation suppressing member 80 described above, first, the fixing screw portion 110 side of the deformation suppressing member 80 is inserted into the insertion hole 55 from the radially outer side. Next, the fixing screw portion 110 is passed through the through hole 64, and the tip surface 101 of the main body portion 100 is brought into contact with the bottom surface 67 of the recess 66. At this time, the back surface 91 of the fixing flange portion 90 comes into contact with the end surface 53 of the fixing seat portion 52. Here, when the back surface 91 comes into contact with the end surface 53, the through hole 92 of the fixing flange portion 90 and the screw hole 54 of the fixing seat portion 52 are adjusted to communicate with each other.

[0071] Next, a bolt 93 is inserted into the through hole 92, and the fixing flange portion 90 is bolted to the fixing seat portion 52. As a result, the fixing flange portion 90 of the deformation suppression member 80 is detachably fixed to the fixing seat portion 52 of the outer peripheral wall 50 from the radially outer side.

[0072] Furthermore, the fixing screw portion 110, which protrudes radially inward from the end face 63 of the fixing seat portion 62, is tightened with a nut 111. As a result, the fixing screw portion 110 of the deformation suppressing member 80 is detachably fixed to the inner circumferential wall 60 from the radially inward side.

[0073] As described above, the deformation suppressing member 80 is detachably attached to the scroll 40A. Similarly, multiple deformation suppressing members 80 are detachably attached to the outer peripheral wall 50 and the inner peripheral wall 60 in the circumferential direction, as shown in Figure 2.

[0074] As described above, the deformation-suppressing member 80 is fixed with its main body 100 penetrating the outer peripheral wall 50 and its fixing screw portion 110 penetrating the inner peripheral wall 60. Therefore, even if, for example, the bolt 93 or nut 111 is damaged, the deformation-suppressing member 80 will not be thrown downstream of the annular passage 70.

[0075] Next, we will explain the operation of gas turbine 1.

[0076] As shown in Figure 1, fuel is supplied into the combustor liner 21 from the fuel nozzle 22. Compressed air 11, which is an oxidizer discharged from the compressor 10, is supplied into the combustor liner 21 from the oxidizer supply unit 23.

[0077] The fuel and compressed air 11 introduced into the combustor liner 21 are combusted to form combustion gas 27. The compressed air 11 is also introduced into the combustor liner 21, for example, through an inlet hole 21a.

[0078] The combustion gas 27 discharged from the combustor liner 21 flows into the scroll 40A. The combustion gas 27 that flows into the bent flow path section 41 of the scroll 40A is deflected by approximately 90 degrees in the axial direction. The deflected combustion gas 27 then flows into the annular flow path section 42. The combustion gas 27 that flows into the annular flow path section 42 spreads out in the circumferential direction.

[0079] The combustion gas 27 spreads uniformly in the circumferential direction within the annular flow path 42. As a result, the flow of the combustion gas 27 has a nearly uniform velocity distribution within the annular flow path of the annular flow path 42.

[0080] The combustion gas 27 then passes through the deformation suppression members 80 provided circumferentially near the outlet 43 of the scroll 40A and is ejected toward the first stage stator vanes 31. At this time, the combustion gas 27 is ejected from the annular outlet 43 at a nearly uniform velocity circumferentially.

[0081] The combustion gas 27 is ejected from the first-stage stationary blades 31 to the first-stage rotor blades 32. The combustion gas 27 introduced into the turbine 30 then rotates the turbine 30. A generator (not shown) is driven by the rotation of the turbine 30 and generates electricity.

[0082] Here, high-temperature combustion gas 27 flows through the scroll 40A. Compressed air 11, which is at a lower temperature than the combustion gas 27, flows around the outer circumference of the scroll 40A. This compressed air 11 also functions as a cooling medium to cool the combustor liner 21 and the scroll 40A.

[0083] Furthermore, the pressure of the compressed air 11 is set higher than the pressure of the combustion gas 27 so that a portion of the compressed air 11 can be introduced into the combustor liner 21. In other words, the pressure of the compressed air 11 flowing around the outer circumference of the scroll 40A is higher than the pressure of the combustion gas 27 flowing through the annular passage 70 of the annular flow path section 42.

[0084] Therefore, a pressure difference (internal-external pressure difference) is generated between the pressure of the combustion gas 27 inside the annular flow channel 42 and the pressure of the compressed air 11 on the outer circumference of the annular flow channel 42. As a result, the annular flow channel 42 is subjected to a force due to this internal-external pressure difference.

[0085] In the annular flow path section 42 of the scroll 40A, the outer peripheral wall 50 is more easily deformed by the internal-external pressure difference than the inner peripheral wall 60. Furthermore, the outlet portion of the outer peripheral wall 50 near the outlet 43 of the scroll 40A is also easily deformed. Due to the internal-external pressure difference, for example, the outer peripheral wall 50 in the horizontal direction deforms radially inward, and the outer peripheral wall 50 in the vertical direction deforms radially outward.

[0086] However, by providing a deformation suppressing member 80 at the exit portion near the exit 43, the radial deformation of the outer peripheral wall 50 of the scroll 40A is suppressed.

[0087] Specifically, radial outward deformation of the outer peripheral wall 50 is suppressed by fixing the fixing screw portion 110 to the inner peripheral wall 60 with a nut 111 and bringing the fixing flange portion 90 into contact with the end face 53 of the fixing seat portion 52. Furthermore, radial inward deformation of the outer peripheral wall 50 is suppressed by bringing the tip surface 101 of the main body portion 100 into contact with the bottom surface 67 of the recess 66 and fixing the fixing flange portion 90 to the outer peripheral wall 50 with a bolt 93.

[0088] Here, the cooling medium introduced into the introduction passage 103 through the introduction hole 94 of the fixed flange portion 90 cools the wall surface of the introduction passage 103 as it flows radially inward. The cooling medium that has cooled the main body portion 100 is then discharged into the annular passage 70 through the discharge hole 104. As a result, the main body portion 100, which is exposed to the combustion gas 27 flowing through the annular passage 70, is cooled.

[0089] As described above, according to the first embodiment of the scroll 40A, by providing the deformation suppression member 80, deformation of the scroll 40A can be suppressed even when an internal-external pressure difference occurs between the inside and outside of the scroll 40A. Furthermore, even when the gas turbine is subjected to further pressure increases and the internal-external pressure difference increases, deformation of the scroll 40A can be suppressed by providing the deformation suppression member 80.

[0090] Furthermore, by providing the deformation suppression member 80, both radial outward deformation of the outer peripheral wall 50 and radial inward deformation of the outer peripheral wall 50 can be suppressed. Therefore, with the deformation suppression member 80, deformation at each position in the circumferential direction of the scroll 40A can be suppressed with a single structure without having to redesign the structure or anything based on the deformation direction of the position where it is placed.

[0091] This makes it possible to maintain a predetermined gap between the outer circumferential wall 50 and the inner circumferential wall 60 at the outlet 43 of the scroll 40A in the circumferential direction. In other words, at the outlet 43 of the scroll 40A, for example, the outer circumferential wall 50 is maintained in the appropriate size and shape, so that the combustion gas 27 can be properly ejected to the first stage stator vanes.

[0092] Since the deformation suppression member 80 is detachably provided on the scroll 40A, the deformation suppression member can be easily replaced.

[0093] Furthermore, by providing a cooling structure to the deformation suppressing member 80, the deformation suppressing member 80 can be used even in temperature environments that exceed the heat resistance temperature of the material constituting the deformation suppressing member 80.

[0094] Here, in the scroll 40A of the first embodiment, the configuration of the deformation suppression member 80 is not limited to the configuration described above.

[0095] For example, if the temperature of the combustion gas 27 flowing through the annular passage 70 is lower than the heat resistance temperature of the material constituting the deformation suppression member 80, the deformation suppression member 80 may be constructed without a cooling structure. In this case, the inlet passage 103 and the discharge hole 104 in the main body portion 100 become unnecessary. Also, the inlet hole 94 in the fixed flange portion 90 becomes unnecessary. In a deformation suppression member 80 without a cooling structure, the main body portion 100 is, for example, made up of a solid column.

[0096] (Second Embodiment) Figure 9 is an enlarged view of the radial cross-section of the exit portion of the scroll 40B in the second embodiment. Note that the deformation suppression member 120 is not shown in the cross-sectional view in Figure 9. Figure 10 is a plan view of the deformation suppression member 120 of the scroll 40B in the second embodiment. Figure 11 is a view of the longitudinal cross-section of the deformation suppression member 120 of the scroll 40B in the second embodiment. Figure 12 is a view of the EE cross-section of Figure 10. Figure 13 is a view of the FF cross-section of Figure 11. Figure 14 is a view of the GG cross-section of Figure 11.

[0097] In the second embodiment, the same reference numerals are used for components identical to the scroll 40A in the first embodiment, and redundant explanations are omitted or simplified.

[0098] In the scroll 40B of the second embodiment, the configuration is the same as that of the scroll 40A of the first embodiment, except for the deformation suppression member 120. Specifically, the cooling structure in the deformation suppression member 120 differs from the cooling structure in the deformation suppression member 80 of the scroll 40A of the first embodiment. Therefore, this section will mainly describe the configuration of the deformation suppression member 120.

[0099] As shown in Figure 9, the deformation suppressing member 120, like the deformation suppressing member 80 in the first embodiment, penetrates radially through the outer circumferential wall 50 and the inner circumferential wall 60 of the annular flow channel 42. One end of the deformation suppressing member 120 is detachably fixed to the outer circumferential wall 50 by a bolt 93. The other end of the deformation suppressing member 120 is detachably fixed to the inner circumferential wall 60 by a nut 111.

[0100] As shown in Figure 10, the deformation suppressing member 120 comprises a fixed flange portion 130, a main body portion 140, and a fixed screw portion 110. The fixed flange portion 130, the main body portion 140, and the fixed screw portion 110 may be formed integrally. Alternatively, the deformation suppressing member 120 may be constructed by joining together the fixed flange portion 130, the main body portion 140, and the fixed screw portion 110, which are each formed separately.

[0101] The configuration of the fixed flange portion 130 is the same as that of the fixed flange portion 90 in the first embodiment, except for the configuration of the introduction hole 133 for introducing a cooling medium into the main body portion 140. As shown in Figure 12, the fixed flange portion 130 has a through hole 132 for passing through a bolt 93 that fixes the fixed flange portion 130 to the fixed seat portion 52. The configuration of the through hole 132 is the same as that of the through hole 92 in the fixed flange portion 90 in the first embodiment.

[0102] Furthermore, the fixed flange portion 130 has an introduction hole 133 formed therein for introducing a cooling medium into the inner cylindrical portion 150 of the main body portion 140. This introduction hole 133 is formed in a position that communicates with the inner cylindrical portion 150 of the main body portion 140.

[0103] The outer edge of the back surface 131 (the surface facing the main body 140) of the fixing flange portion 130, which is composed of a circular, flat plate-shaped member, abuts against the end surface 53 of the fixing seat portion 52. The fixing flange portion 130 is detachably fastened to the fixing seat portion 52 from the radially outer side by bolts 93.

[0104] The main body portion 140 extends from the back surface 131 of the fixed flange portion 130 in a direction perpendicular to the back surface 131. As shown in Figures 11, 13, and 14, the main body portion 140 comprises an inner cylinder portion 150 and an outer cylinder portion 160.

[0105] The inner cylinder portion 150 is composed of a cylindrical member that introduces a cooling medium into the main body portion 140. The outer cylinder portion 160 is composed of a cylindrical member provided on the outside of the inner cylinder portion 150 so as to surround the inner cylinder portion 150. In other words, the inner cylinder portion 150 is housed within the outer cylinder portion 160 with a predetermined gap between them.

[0106] In other words, as shown in Figures 13 and 14, the main body 140 has a double-tube structure composed of an inner cylinder 150 and an outer cylinder 160. This creates a space 170 between the inner surface 161 of the outer cylinder 160 and the outer surface 151 of the inner cylinder 150.

[0107] In the inner cylinder portion 150 and the outer cylinder portion 160, as shown in Figures 13 and 14, the shape of the cross section perpendicular to the longitudinal direction (cross section perpendicular to the radial direction) is configured to be elliptical. In this case, the leading edge 162 of the outer cylinder portion 160 is positioned toward the upstream of the combustion gas 27 flow, and the trailing edge 163 of the outer cylinder portion 160 is positioned toward the downstream of the combustion gas 27 flow. By making the shape of the outer cylinder portion 160 a streamlined shape such as an ellipse, the pressure loss in the combustion gas 27 flow is reduced.

[0108] As shown in Figure 11, one end of the outer cylinder portion 160 is joined to the back surface 131 of the fixed flange portion 130. The other end of the outer cylinder portion 160 is sealed by a sealing end wall 164. The outer cylinder portion 160 may be composed of a cylindrical member with one end open and the other end closed. In this case, the sealing end wall 164 is not necessary.

[0109] The inner cylinder portion 150 is composed of, for example, a cylindrical member with both ends open. For example, one end of the inner cylinder portion 150 is connected to the back surface 131 of the fixed flange portion 130, and the other end of the inner cylinder portion 150 is in contact with the sealing end wall 164.

[0110] The inner cylinder portion 150 is provided with a plurality of ejection holes 152 that eject the cooling medium introduced inside toward the inner surface 161 of the outer cylinder portion 160. The ejection holes 152 are provided at predetermined intervals in the longitudinal direction (radial direction) of the inner cylinder portion 150, for example. The ejection holes 152 are also provided at predetermined intervals from the leading edge 153 toward the trailing edge 154, for example. As shown in Figure 14, most of the ejection holes 152 are provided closer to the leading edge 153 than to the trailing edge 154. This allows for active cooling of the leading edge 162 side of the outer cylinder portion 160, which becomes hot.

[0111] The outer cylinder portion 160 has a plurality of discharge holes 165 for discharging the cooling medium ejected from the ejection holes 142 to the outside. When the deformation suppression member 120 is fixed to the scroll 40B, the discharge holes 165 discharge the cooling medium into the annular passage 70.

[0112] The discharge hole 165 is formed at a position offset from the position opposite to the position where the ejection hole 152 is formed. In other words, the discharge hole 165 is positioned so that the cooling medium ejected from the ejection hole 152 is not directly discharged to the outside through the discharge hole 165. As a result, the cooling medium ejected from the ejection hole 152 collides with the inner surface 161 of the outer cylinder portion 160. By causing the cooling medium to collide with the inner surface 161 in this way, impingement cooling is promoted, which accelerates the cooling of the outer cylinder portion 160.

[0113] Most of the discharge holes 165 are located on the front edge 162 side of the outer cylinder portion 160, as shown in Figures 10 and 13. In this case, the front edge 162 side of the outer cylinder portion 160 is hotter than the rear edge 163 side. Therefore, by discharging the cooling medium from the front edge 162 side, a region is formed where the cooling medium exists between the combustion gas 27 and the outer surface 166 of the outer cylinder portion 160. This film cooling prevents the combustion gas 27 from directly contacting the outer surface 166, thereby suppressing the temperature rise of the outer cylinder portion 160.

[0114] When the deformation suppressing member 120 is fixed to the scroll 40B, as shown in Figure 9, the main body portion 140 extending radially inward from the back surface 131 of the fixing flange portion 130 penetrates the outer peripheral wall 50, and the end face of the sealing end wall 164 of the outer cylinder portion 160 abuts against the bottom surface 67 of the recess 66 in the inner peripheral wall 60.

[0115] Here, the fixing screw portion 110 is composed of a rod-shaped screw member extending from the sealing end wall 164 of the outer cylinder portion 160 in a direction perpendicular to the end face of the sealing end wall 164. The fixing screw portion 110 is as described above.

[0116] The process of fixing the deformation suppression member 120 to the scroll 40B is the same as the process of fixing the deformation suppression member 80 to the scroll 40A described above. Similar to the deformation suppression member 80, multiple deformation suppression members 120 are provided in the circumferential direction of the outlet portion of the scroll 40B (annular flow channel 42).

[0117] In the scroll 40A equipped with the deformation suppression member 120 described above, the cooling medium is introduced into the inner cylinder portion 150 through the introduction hole 133 of the fixed flange portion 130. The cooling medium introduced into the inner cylinder portion 150 spreads within the inner cylinder portion 150 and is ejected from the ejection hole 152 toward the inner surface 161 of the outer cylinder portion 160.

[0118] The cooling medium ejected from the ejection holes 152 collides with the inner surface 161, cooling the outer cylinder portion 160 from the inside. This impingement cooling promotes the cooling of the outer cylinder portion 160.

[0119] The cooling medium that collides with the inner surface 161 is discharged from the discharge hole 165 into the annular passage 70. At this time, film cooling prevents the combustion gas 27 from directly contacting the outer surface 166 of the outer cylinder portion 160, thereby suppressing the temperature rise of the outer cylinder portion 160.

[0120] In the scroll 40B of the second embodiment, as in the scroll 40A of the first embodiment, the deformation suppressing member 120 suppresses radial deformation of the outer peripheral wall 50. Specifically, radial outward deformation of the outer peripheral wall 50 is suppressed by fixing the fixing screw portion 110 to the inner peripheral wall 60 with a nut 111 and bringing the fixing flange portion 130 into contact with the end face 53 of the fixing seat portion 52. Furthermore, radial inward deformation of the outer peripheral wall 50 is suppressed by bringing the tip end face of the outer cylinder portion 160 into contact with the bottom surface 67 of the recess 66 and fixing the fixing flange portion 130 to the outer peripheral wall 50 with a bolt 93.

[0121] As described above, the scroll 40B of the second embodiment provides the same effects as the scroll 40A of the first embodiment regarding the deformation of the scroll 40B by including the deformation suppressing member 120. That is, by including the deformation suppressing member 120, the deformation of the scroll 40B can be suppressed even when an internal-external pressure difference occurs between the inside and outside of the scroll 40B.

[0122] Furthermore, by providing the deformation suppression member 120, both radial outward deformation and radial inward deformation of the outer peripheral wall 50 can be suppressed. Since the deformation suppression member 120 is detachably provided on the scroll 40B, the deformation suppression member can be easily replaced.

[0123] By providing a cooling structure to the deformation suppressing member 120, the deformation suppressing member 120 can be used even in temperature environments that exceed the heat resistance temperature of the material constituting the deformation suppressing member 120. Furthermore, the cooling structure of the deformation suppressing member 120 promotes cooling of the deformation suppressing member 120 by utilizing impingement cooling and film cooling.

[0124] (Other embodiments)

[0125] In the embodiment described above, an example is shown in which the combustor 20 is located on the upper half, but the configuration is not limited to this. The combustor 20 may also be located on the lower half. In this case, the combustor 20 is positioned to penetrate the casing 5, for example, from vertically downwards. Furthermore, the combustor 20 may be located on both the upper and lower halves.

[0126] Furthermore, although the above-described embodiment shows an example with a casing 5, the casing structure may be a double casing structure with an outer casing on the outer circumference of an inner casing.

[0127] According to the embodiments described above, by providing a deformation suppression member, deformation of the scroll exit can be suppressed over the circumferential direction, and the deformation suppression member can be easily replaced.

[0128] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of symbols]

[0129] 1...Gas turbine, 5...Casing, 10...Compressor, 11...Compressed air, 12...Guide member, 20...Combustor, 21...Combustor liner, 21a...Inlet hole, 22...Fuel nozzle, 23...Oxidizer supply section, 24...Combustor casing, 25...Lid member, 26...Fuel supply pipe, 27...Combustion gas, 30...Turbine, 31...Stator blade, 32...Motor blade, 33...Turbine rotor, 40A, 40B...Scroll, 41...Bent passage section, 42...Annular passage section, 43...Outlet, 50...Outer peripheral wall, 51, 65...Outer peripheral surface, 52, 62...Fixed seat section, 53, 63...End face, 54...Screw hole, 55...Insertion hole, 60...Inner peripheral wall, 61...Inner peripheral surface, 64, 92 ,132...through hole, 66...recess, 67...bottom surface, 70...annular passage, 80, 120...deformation suppressing member, 90, 130...fixing flange part, 91, 131...back surface, 93...bolt, 94, 133...inlet hole, 100, 140...main body part, 101...tip surface, 102...tip part, 103...inlet passage, 104, 165...discharge hole, 105, 153, 162...front edge, 106, 154, 163...rear edge, 110...fixing screw part, 111...nut, 112...thread, 142, 152...ejection hole, 150...inner cylinder part, 151, 166...outer surface, 160...outer cylinder part, 161...inner surface, 164...sealing end wall, 170...space, O...central axis.

Claims

1. A scroll for a gas turbine that guides combustion gases discharged from a combustor to a turbine by causing them to flow in the axial direction and circumferential direction of the turbine rotor, The outer wall and The outer peripheral wall and the annular passage are formed, and an inner peripheral wall is provided on the turbine rotor side of the outer peripheral wall with a predetermined gap between it and the outer peripheral wall, A plurality of deformation suppressing members are provided in the circumferential direction of the outlet portion of the scroll, penetrating the outer and inner circumferential walls in the radial direction of the turbine rotor, with one end detachably fixed to the outer circumferential wall and the other end detachably fixed to the inner circumferential wall. Equipped with, A scroll for a gas turbine, characterized in that each of the deformation-suppressing members is fastened to the outer peripheral wall and the inner peripheral wall by bolts or nuts.

2. One end of each deformation suppressing member is fixed to the radially outer outer surface of the outer wall, The scroll of a gas turbine according to claim 1, characterized in that the other end of each deformation suppressing member is fixed to the radially inner inner surface of the inner circumferential wall.

3. A first fixing seat portion is formed on the outer surface of the outer wall for fixing one end of each deformation suppressing member, The scroll of a gas turbine according to claim 2, characterized in that a second fixing seat portion for fixing the other end of each of the deformation suppressing members is formed on the inner surface of the inner wall.

4. Each of the deformation suppressing members is A fixing flange portion that abuts against the first fixing seat portion from the radially outer side and is fastened by a bolt, A main body portion extending radially inward from the fixed flange portion, penetrating the outer peripheral wall and contacting the radially outer peripheral surface of the inner peripheral wall, A fixing screw portion extends radially inward from the main body portion, penetrates the inner circumferential wall, and is fastened to the second fixing seat portion by a nut. A scroll for a gas turbine according to claim 3, characterized by comprising the above.

5. The main body portion is An introduction passage for introducing a cooling medium into the main body, A discharge hole for discharging the cooling medium introduced into the introduction passage into the annular passage. Equipped with, The aforementioned fixed flange portion is The scroll of a gas turbine according to claim 4, characterized in that it is provided with an introduction hole that communicates with the introduction passage and introduces a cooling medium into the introduction passage from the outside of the scroll.

6. The main body is, The main body is composed of a cylindrical member into which a cooling medium is introduced, and the inner cylinder has an ejection hole for ejecting the introduced cooling medium, An outer cylinder portion is formed by a cylindrical member that surrounds the inner cylinder portion, and has a discharge hole formed at a position offset from the position opposite to the position where the ejection hole is formed, for discharging the cooling medium ejected from the ejection hole into the annular passage. Equipped with, The aforementioned fixed flange portion is The scroll of a gas turbine according to claim 4, characterized in that it has an introduction hole that communicates with the inside of the inner cylinder and introduces a cooling medium into the inside of the inner cylinder from the outside of the scroll.

Images