GAS TURBINE COMBUSTION CHAMBER

Abstract

Gas turbine combustion chamber (4), comprising: a tubular body (912) defining a combustion chamber (31), extending from a first side to a second side in an axial direction (X) and defining an outlet opening (32) located on the second side in the axial direction (X); an air passage (16) through which air (A) is supplied to the combustion chamber (31); at least one resonator (18) having at least one opening (41) open towards the air passage (16) and a resonance chamber (43) connected to the opening (41), and a guide plate (17) having a guide hole (17a);wherein: the air passage (16) comprises an upstream region (R1) extending along an outer circumferential surface of the tubular body (912), a downstream region (R3) extending along an inner circumferential surface of the tubular body (912), located on the first side of the combustion chamber (31) in the axial direction (X) and connected to the combustion chamber (31), and a change of direction region (R2) connecting the upstream region (R1) with the downstream region (R3) in a radial direction (Y) of the tubular body (912) and adjoining the upstream region (R1), such that an area of ​​a section or cross-section of the air duct (16), which is orthogonal to the axial direction (X), changes at a position between the upstream region (R1) and the change of direction region (R2);the opening (41) of the resonator (18) is open to a space of the air duct (16) located downstream of the upstream area (R1); the guide plate (17) divides the space of the air duct (16) located downstream of the upstream area (R1) into a guide space (33a) and a message space (33b); and the opening (41) of the at least one resonator (18) is open to the message space (33b).

Description

Technical area

[0001] The present disclosure relates to a combustion chamber or burner of a gas turbine engine. Background Art

[0002] A gas turbine combustion chamber is known, on which a resonator is mounted to reduce the vibrations generated by combustion. In PTL 1, the resonator is mounted on a combustion insert that defines a combustion chamber, and a resonance chamber of the resonator is open towards the combustion chamber. In PTL 2, the resonator is mounted on a flow sleeve located on a radially outer side of the combustion insert that delimits the combustion chamber, and the resonance chamber of the resonator is open towards an air passage delimited by the flow sleeve. Citation list for patent literature PTL 1: Japanese open patent application Publication No. 2018-159533 PTL 2: Japanese published patent application Publication No. 2013-234833 Summary of the invention: Technical problem

[0003] In the PTL 1 configuration, heat from the combustion chamber is transferred directly to the resonance chamber, and the resonator heats up considerably. If the resonator is specifically cooled and the combustion temperature is increased by a temperature corresponding to the cooling of the resonator, NOx emissions can rise. In the PTL 2 configuration, the heat transferred from the combustion chamber to the resonator is reduced, but there is still room for improvement regarding vibration reduction. Solution to the problem

[0004] A gas turbine combustion chamber according to one aspect of the present disclosure comprises: a tubular body defining a combustion chamber, extending from a first side to a second side in an axial direction and defining an outlet opening located on the second side in the axial direction; an air passage through which air is supplied to the combustion chamber; and at least one resonator comprising at least one opening open towards the air passage.The air passage comprises: an upstream region extending along an outer circumferential surface of the tubular body; a downstream region extending along an inner circumferential surface of the tubular body, located at the first side of the combustion chamber in the axial direction and connected to the combustion chamber; and a change-of-direction region connecting the upstream region to the downstream region in a radial direction of the tubular body and adjacent to the upstream region, such that an area of ​​a section of the air passage, orthogonal to the axial direction, changes at a position between the upstream region and the change-of-direction region. The opening is open to a space of the air duct located downstream of the upstream region.

[0005] A gas turbine combustion chamber according to one aspect of the present disclosure comprises: a tubular body defining a combustion chamber, extending from a first side to a second side in an axial direction, and defining an outlet opening located on the second side in the axial direction; and an air passage through which air is supplied to the combustion chamber. The air passage comprises: an upstream region extending along an outer circumferential surface of the tubular body; a downstream region extending along an inner circumferential surface of the tubular body, located on the first side of the combustion chamber in the axial direction, and communicating with the combustion chamber; and a change-of-direction region connecting the upstream region to the downstream region in a radial direction of the tubular body.The tubular body contains a leakage hole that connects the downstream area with the upstream area, excluding the direction change area. Advantageous effects of the invention

[0006] According to one aspect of the present disclosure, a special cooling structure is not required, and the vibrations generated by combustion can be effectively reduced. Brief description of the drawings Fig. Figure 1 is a schematic representation of a gas turbine engine. Fig. Figure 2 is a perspective sectional view of a combustion chamber of embodiment 1. Fig. 3 is a cross-sectional view of the in Fig. 2 shown combustion plant. Fig. 4 is a diagram to illustrate the propagation of low-frequency pressure waves in the Fig. 3 combustion chamber shown. Fig. 5 is a diagram to illustrate the propagation of high-frequency pressure waves in the Fig. 3 combustion chamber shown. Fig. Figure 6 is a diagram illustrating a difference between the propagation paths of pressure waves in a [context missing]. Fig. 3 direction change area shown. Fig. 7A is a perspective view that is a modified example of one in Fig. The 3 depicted resonators show. Fig. 7B is a sectional view along line VIIB-VIIB of Fig. 7A. Fig. 7C is a sectional view along line VIIC-VIIC of Fig. 7A. Fig. 8A is a main component section view, which is a first modified example of the in Fig. 3 shows the combustion chamber. Fig. 8B is a principal component section view, which is a second modified example of the one shown in Fig. 3 shows the combustion chamber. Fig. 8C is a principal component section view, which is a third modified example of the one in Fig. 3 shows the combustion chamber. Fig. Figure 9 is a main component sectional view of the combustion chamber of embodiment 2. Fig. 10A is a perspective view, a modified example of the one in Fig. The 9 depicted resonators show. Fig. 10B is a section view along the XB-XB line of Fig. 10A. Fig. 11A is a main component section view, which is a first modified example of the in Fig. The combustion chamber shown is depicted in section 9. Fig. 11B is a principal component section view, which is a second modified example of the one shown in Fig. The combustion chamber shown is depicted in section 9. Fig. Figure 12 is a main component sectional view of the combustion chamber of embodiment 3. Fig. Figures 13A to 13C are schematic representations showing variations of an air duct in the combustion chamber. Fig. Figure 14 is a main component sectional view of the combustion chamber of embodiment 4. Fig. Figure 15 is a main component sectional view of the combustion chamber of embodiment 5. Description of the embodiments

[0007] The embodiments are described below with reference to the drawings.

[0008] Fig. Figure 1 is a schematic representation of a gas turbine engine 1. As in Fig. As shown in Figure 1, the gas turbine engine or gas turbine machine 1 (hereinafter referred to as the gas turbine) comprises a rotating shaft 2, a compressor 3, a combustion chamber 4, and a turbine 5. In the gas turbine 1, the compressed air supplied by the compressor 3 is introduced into the combustion chamber 4. In the combustion chamber 4, a fuel-air mixture is burned, which consists of a mixture of fuel supplied from a fuel feed line and the compressed air supplied by the compressor 3. The turbine 5 is driven by the combustion gas exiting the combustion chamber 4 at high temperature and high pressure. The turbine 5 is mechanically connected to a load 6 (e.g., a generator) and the compressor 3 via the rotating shaft 2. Design 1

[0009] Fig. Figure 2 is a perspective sectional view of the combustion chamber 4 of embodiment 1. Fig. 3 is a sectional view of the Fig. 2. Combustion chamber 4 as shown. In the following description, a direction in which an axis C of a housing 11 and a tubular body 12 extends is referred to as the “axial direction X”. In the axial direction X, a side of the tubular body 12 opposite a side on which an outlet opening 32 is located is referred to as the “first side”, and the side on which the outlet opening 32 is located is referred to as the “second side”. A direction that is orthogonal to the axial direction X is referred to as the “radial direction Y”. A direction that extends circumferentially around the axis C is referred to as the “circumferential direction Z”.

[0010] The combustion chamber 4 (also called gas turbine combustion chamber) is, for example, one of the shell-shaped combustion chambers that are arranged in a ring around the rotating shaft 2 of the gas turbine 1 (see Fig. 2) Combustion chamber 4 is not limited to this and can also be used for a gas turbine with only one combustion chamber. As in the Fig. 2 and Fig. As shown in Figure 3, the combustion chamber 4 comprises the housing 11, the tubular body 12, a fuel injection nozzle 13, an igniter 14, a fuel supply structure 15, an air duct 16, a guide plate 17 and a resonator 18.

[0011] The housing 11 comprises a tubular housing 21 and an end plate 22. The tubular housing 21 has a tubular shape and extends from the first side (left side in Fig. 3) to the second page (right side in Fig. 3) in the axial direction X. The tubular housing 21 includes an air inlet 30, which is open on the second side to allow air A from the compressor 3 (see Fig. 1) to be included. The end plate 22 is located on the first side of the tubular body 12 in the axial direction X and has an inner surface facing the air passage 16 described below. The end plate 22 closes an opening of the tubular housing 21 located on the first side. The end plate 22 is attached by a fastener to an end section of the tubular housing 21 located on the first side.

[0012] The tubular body 12 is housed within the casing 11. The axis C of the tubular body 12 coincides with the axis of the casing 11. The tubular body 12 comprises a combustion liner 23 as the first lining and a support liner 24 as the second lining. The combustion liner 23 defines a combustion chamber 31 within its interior. The outlet opening 32 of the combustion liner 23 is open to the second side. The support liner 24 is located on the first side of the combustion liner 23 and is arranged coaxially with it. The support liner 24 defines an air chamber 33 on its inner side in the radial direction Y. The heat resistance of a material (e.g., a cobalt or nickel alloy) for the combustion liner 23 is higher than the heat resistance of a material (e.g., stainless steel) for the support liner 24.The tubular body 12 can contain only the combustion lining 23, and the support lining 24 can be omitted.

[0013] The fuel injector 13 is housed in the tubular body 12. The fuel injector 13 comprises a fuel injection port 13a, which is open towards the combustion chamber 31. The fuel injection port 13a injects fuel F, supplied by the fuel supply structure 15 described below, together with the air A supplied by the air chamber 33, into the combustion chamber 31. The fuel injector 13 is located on the first side of the combustion chamber 31 in the axial direction X. In the present embodiment, the fuel injector 13 is arranged, for example, such that it corresponds to a boundary between the combustion lining 23 and the support lining 24 and separates the combustion chamber 31 and the air chamber 33.

[0014] The fuel F is a gaseous fuel, such as a carbon-containing gas (natural gas or propane) or a hydrogen-containing gas (hydrogen gas), but can also be a liquid fuel. Furthermore, the fuel F and the air A can be pre-mixed and injected as a fuel-air mixture into the combustion chamber 31 or mixed together within the combustion chamber 31.

[0015] The igniter 14 penetrates the tubular housing 21 and the combustion insert 23 in radial direction Y, and an ignition section 14a of the igniter 14 is exposed to the combustion chamber 31. When the combustion chamber 4 is started, the fuel-air mixture injected into the combustion chamber 31 by the fuel injector 13 is ignited by the igniter 14, creating a flame in the combustion chamber 31. A high-temperature and high-pressure combustion gas G generated in the combustion chamber 31 is discharged through the outlet opening 32.

[0016] The fuel supply structure 15 can supply the fuel F, which is supplied from a fuel supply line located outside the housing 11, to the fuel injection valve 13. The configuration of the fuel supply structure 15 is not particularly limited or restricted. In the present embodiment, the fuel supply structure 15 comprises, for example, a main line 25 and branch lines 26 and 27 extending from the main line 25.

[0017] The main tube 25 penetrates the end plate 22 on the axis C of the tubular body 12 and extends in the axial direction X. One end section of the main tube 25 is located in the air chamber 33, and the other end section of the main tube 25 is located outside the housing 11. The main tube 25 has a multi-tube structure in which cylindrical tubes are arranged coaxially. The fuel supply channels 25a and 25b, with circular tubes, are located coaxially within the main tube 25. The branch lines 26 and 27 connect the main tube 25 to the fuel injector 13. An inner surface of the branch line 26 communicates with a fuel supply channel 25a, and an inner surface of the branch line 27 communicates with a fuel supply channel 25b.

[0018] Each of the branch pipes 26 and 27 comprises: a section projecting outwards in the radial direction Y from the main pipe 25, and a section extending in the axial direction X towards the fuel injector 13. The positions where branch pipe 26 connects to the fuel injector 13 in the radial direction Y and where branch pipe 27 connects to the fuel injector 13 in the radial direction Y are distinct. The fuel flow rates F supplied to the respective sections of the fuel injector 13 can be controlled independently by adjusting the opening degrees of flow control valves, which regulate the flow rates of the fuel supply channels 25a and 25b.

[0019] Air duct 16 carries the air from compressor 3 (see Fig. 1) supplied air A to the combustion chamber 31. The air duct 16 has such a reverse flow shape that it extends from the air inlet 30 as the starting point to the first side in the axial direction X and returns to the second side in the axial direction X.

[0020] The air passage 16 comprises an air inlet channel 34, which is a gap between an inner circumferential surface of the housing 11 and an outer circumferential surface of the tubular body 12. The air supplied by the compressor 3 (see Fig. 1) Compressed air A is introduced through the air inlet 30 into the air inlet 34, and the air inlet 34 directs the air A in a direction opposite to the flow direction of the combustion gas G in the combustion chamber 31. An axial flow gas turbine can be used in which the flow direction of the air A and the flow direction of the combustion gas G are identical.

[0021] A portion of the support lining 24, located on the first side, includes air inlet openings 35 arranged in the circumferential direction Z. However, an air inlet opening of the support lining 24 can be large enough to encompass the air inlet openings 35. The air inlet openings 35 connect the air inlet channel 34 to the air chamber 33. The air A, flowing through the air inlet channel 34, passes through the air inlet openings 35 and is directed to the air chamber 33, located on the inner side of the support lining 24 in the radial direction Y. The air A, having been directed to the air chamber 33, flows to the fuel injection device 13 and is mixed with the fuel F in the fuel injection device 13.

[0022] The alignment plate 17 is arranged orthogonally to axis C in the support lining 24. The alignment plate 17 is located on the second side of the air inlet openings 35 in the axial direction X. An outer circumferential section of the alignment plate 17 is attached to the support lining 24. An inner circumferential section of the alignment plate 17 is attached to the end plate 22 via a tubular bracket that is mounted on the outside of the main tube 25. The alignment plate 17 contains alignment holes 17a. The alignment plate 17 divides the air chamber 33 into two spaces aligned in the axial direction X. More precisely, the alignment plate 17 divides the air chamber 33 into a setup space 33a and a communication space 33b.

[0023] The pre-assembly chamber 33a is a chamber located on the first side of the air chamber 33 and adjacent to the air inlet openings 35. The communication or post-assembly chamber 33b is a chamber located on the second side of the air chamber 33 and adjacent to the fuel injector nozzle 13. The pre-assembly plate 17 is located on the second side of the air inlet openings 35 in the axial direction X. The pre-assembly plate 17 aligns the air A introduced into the air chamber 33 from the air inlet openings 35 to create a uniform flow to the combustion chamber 31. The pre-assembly plate 17 can also be omitted.

[0024] In the present embodiment, the air duct 16 is formed by the air inlet duct 34, the air inlet openings 35, and the air chamber 33. The air duct 16 can be divided into an upstream region R1, a direction change region R2, and a downstream region R3.

[0025] The upstream region R1 is located between the air inlet 30 and the air inlet openings 35 in the axial direction X and along the outer circumferential surface of the tubular body 12. The upstream region R1 is part of the air inlet duct 34. The downstream region R3 is located between the air inlet openings 35 and the fuel injector 13 in the axial direction X and along an inner circumferential surface of the tubular body 12. The downstream region R3 is part of the air chamber 33. The direction change region R2 connects the upstream region R1 with the downstream region R3.

[0026] The direction change region R2 borders the upstream region R1, such that the area of ​​a section of the air duct 16, which is orthogonal to the axial direction X, changes at a position between the upstream region R1 and the direction change region R2. A virtual boundary plane M between the upstream region R1 and the direction change region R2 is a virtual plane that passes through the ends E of the air inlet openings 35, which are located on the second side in the axial direction X, and is orthogonal to the axial direction X.More precisely, the virtual boundary plane M is a virtual plane which: passes through an end E located on the second side in the axial direction X of a section of the air duct 16 extending in the radial direction Y to connect the upstream region R1 with the downstream region R3; is orthogonal to the axial direction X; and is located outside the end E in the radial direction Y.

[0027] A virtual boundary plane N between the direction change region R2 and the downstream region R3 is also a virtual plane that passes through the ends E of the air inlet openings 35 and is orthogonal to the axial direction X. More precisely, the virtual boundary plane N is a virtual plane that: passes through the end E located on the second side in the axial direction X of the section of the air duct 16 that extends in the radial direction Y to connect the upstream region R1 with the downstream region R3; is orthogonal to the axial direction X; and lies within the end E in the radial direction Y. The guide plate 17 is located in the downstream region R3.

[0028] The resonator 18 (first resonator) comprises openings 41, chokes 42, and a resonance chamber 43. The openings 41 are open, facing a space (the direction-change region R2 or the downstream region R3) of the air duct 16 located downstream of the virtual boundary plane M. In the present embodiment, the openings 41 face directly toward the downstream region R3 and are open in the direction of the downstream region R3 at an inner circumferential surface of the support lining 24. The openings 41 are continuously connected to the downstream region R3. The resonator 18 utilizes a portion of the support lining 24. The chokes 42 are passages connecting the openings 41 to the resonance chamber 43. The resonance chamber 43 is a space larger than the chokes 42.The areas of the openings 41, the lengths of the chokes 42, and the volume of the resonance chamber 43 are determined depending on the frequency to be damped. The support body 24 can project outwards in the radial direction Y, and the resonator 18 can be located within this radially projecting portion. In this case, a plate with the openings 41 and the chokes 42 is located between the downstream region R3 and the resonance chamber 43. More precisely, the inner circumferential surface of the support lining 24 utilizes a surface of the plate of the resonator 18 that is located internally in the radial direction Y.

[0029] The openings 41 of the resonator 18 are open towards the air duct 16, which is located upstream of the combustion chamber 31. Therefore, the temperature inside the resonator 18 is lower than if the openings 41 were open towards the combustion chamber. Consequently, the resonator 18 does not require special cooling. A dedicated cooling structure is therefore unnecessary. Furthermore, the combustion temperature does not need to be increased by a temperature equivalent to that required for cooling the resonator 18. In this way, an increase in NOx emissions can be prevented.

[0030] The area of ​​the section of air duct 16 that runs orthogonally to the axial direction X changes at the boundary (virtual interface M) between the upstream region R1 and the region of change of direction R2. Pressure waves transmitted in the air, which travel back along air duct 16 from the combustion chamber 31 due to combustion vibrations, are partially reflected or canceled out on a downstream side of the virtual interface M. If the pressure change in combustion chamber 4 is simplified and attention is focused on the transmission of the pressure waves generated in combustion chamber 31, this reflection effect causes the sound pressure in a section of air duct 16 located downstream of the upstream region R1 to be higher than the sound pressure in the upstream region R1.Therefore, if the openings 41 are open towards the space of the air duct 16, which is located downstream of the upstream area R1, the pressure waves transmitted in the air from the combustion chamber 31 to the air duct 16 can be effectively absorbed, and the vibration generated by the combustion can be reduced.

[0031] Fig. Figure 4 is a diagram illustrating the propagation of low-frequency pressure waves in the Fig. 3 combustion chamber shown 4. With reference to Fig. Section 4 below describes a pressure wave with a relatively low frequency, i.e., a pressure wave whose wavelength can be considered long relative to the size of the propagation space. In this case, a pressure wave P1, traveling backwards from the combustion chamber 31 in the air duct 16, moves in the axial direction X towards the first side and is reflected by a wall surface of the direction-change region R2 on the first side in the axial direction X. Its reflected wave P2 travels in the axial direction X towards the second side. The reflected wave P2 is split into components: one reflected from the ends E of the air inlet openings 35 and the other components. The components reflected from the wall surface remain within the direction-change region R2.The components not reflected from the ends E are split into components that propagate in the upstream region R1 and components that remain in the region of change of direction R2 and the downstream region R3. Therefore, the pressure wave propagating in the upstream region R1 is smaller than the pressure wave in the space downstream of the virtual interface M. More precisely, the sound pressure in the region of change of direction R2 and the downstream region R3 is greater than the sound pressure in the upstream region R1. Therefore, if the openings 41 are open towards the space of the air duct 16 located downstream of the upstream region R1, the pressure waves transmitted in the air from the combustion chamber 31 to the air duct 16 can be effectively absorbed.

[0032] Fig. Figure 5 is a diagram illustrating the propagation of high-frequency pressure waves in the Fig. 3 combustion chamber shown 4. With reference to Fig. Section 5 below describes the pressure wave whose frequency is relatively high, i.e., the pressure wave whose wavelength can be considered short relative to the size of the propagation space. In this case, the pressure wave, which travels backward from the combustion chamber 31 in the air duct 16, is split into components P3, which are reflected from the wall surface of the direction-change region R2, and components P4, which rotate along a transit axis of the direction-change region R2 and are transmitted into the upstream region R1. The components P3 of the pressure wave that are reflected from the wall surface of the direction-change region R2 remain in the direction-change region R2 and in the downstream region R3 (some of the components P3 may be transmitted into the upstream region R1).Therefore, the sound pressure in the direction change region R2 and in the downstream region R3 is greater than the sound pressure in the upstream region R1. If the openings 41 are open towards the space of the air duct 16, which is located downstream of the upstream region R1, the pressure waves transmitted in the air from the combustion chamber 31 to the air duct 16 can be effectively absorbed.

[0033] Fig. Figure 6 is a diagram illustrating a difference between the propagation paths of pressure waves in the area described in Fig. 3 direction change area R2 shown. As in Fig. As shown in Figure 6, the propagation of the pressure wave in a curved passage of the direction-change region R2 generates a difference between an inner circumferential path P5 and an outer circumferential path P6 in the curved passage. There is a difference between the phase of the pressure wave traveling through the inner circumferential path P5 and the phase of the pressure wave traveling through the outer circumferential path P6. At the virtual interface M, the pressure waves partially cancel each other out due to interference, with the pressure waves whose phases differ superimposed. Therefore, the sound pressure in the direction-change region R2 and in the downstream region R3 is greater than the sound pressure in the upstream region R1.When the openings 41 are open towards the space of the air duct 16, which is located downstream of the upstream area R1, the pressure waves transmitted in the air from the combustion chamber 31 to the air duct 16 can be effectively absorbed.

[0034] Specifically, the openings 41 of the resonator 18 face downstream of and are open towards the downstream region R3. The area of ​​the passage section of the air duct 16, which is orthogonal to the axis direction X, also changes at the virtual boundary plane N between the direction change region R2 and the downstream region R3. The downstream region R3 is closer to the combustion chamber 31 than the direction change region R2. Therefore, when the openings 41 of the resonator 18 are open towards the downstream region R3, the pressure waves can be absorbed even more effectively.

[0035] Specifically, the openings 41 of the resonator 18 face the communication chamber 33b and are open towards it. The area of ​​the passage section of the air duct 16, which is orthogonal to the axial direction X, also changes at the guide holes 17a of the guide plate 17, and partial reflection of the pressure waves occurs at the guide plate 17. Therefore, when the openings 41 of the resonator 18 are open towards the communication chamber 33b, the pressure waves can be absorbed more effectively.

[0036] Since resonator 18 is open to air duct 16, through which only air flows, the gas introduced into resonator 18 is not a fuel-containing gas, such as a fuel-air mixture. The fuel content of the fuel-air mixture changes depending on the engine power, and the speed of sound changes accordingly. Therefore, it is difficult to determine or provide a resonant frequency with respect to the fuel-air mixture. Because resonator 18 is open to air duct 16, this problem is avoided. The fuel-air mixture consisting of air and fuel can flow through air duct 16.

[0037] The resonator 18 is housed in the casing 11 and is located on the support lining 24. The resonator 18 comprises, for example, a resonator main body 50, which is attached to an outer circumferential surface of the support lining 24. The resonator 18 is formed by the resonator main body 50 and a portion of the support lining 24. The resonator main body 50 is a cylindrical hollow element. The chokes 42 are through holes located on an inner circumferential wall of the resonator main body 50 and the support lining 24.

[0038] The length of the choke 42 in the radial direction Y can be determined by the thickness of the inner circumferential wall of the resonator main body 50. The openings 41 are openings of the aforementioned through-holes of the support body 24, which are located internally in the radial direction Y. The openings 41 are arranged in a row in the axial direction X and in the circumferential direction Z. All openings 41 and the chokes 42 are connected to a resonance chamber 43. However, the present embodiment is not limited to this. The resonance chamber 43 can be subdivided into cavities.

[0039] The resonator 18 can be arranged on a portion of the outer circumferential surface of the support lining 24 in the circumferential direction Z, without being arranged on the entire outer circumferential surface of the support lining 24 in the circumferential direction Z. In this case, a gap between an inner circumferential surface of the cover element and the outer circumferential surface of the support lining 24 can be used as a resonance chamber 43.

[0040] The resonator 18 projects further towards the upstream region R1 than a portion of the support lining 24 that borders the resonator 18 in the axial direction X. More precisely, an outer circumferential surface of the resonator 18 is located in the radial direction Y outside an outer circumferential surface of the portion of the support lining 24 that borders the resonator 18 in the axial direction X. In the present embodiment, the main resonator body 50, which is attached to the outside of the support lining 24, is arranged such that it projects from the support lining 24 towards the upstream region R1. The inner circumferential surface of the support lining 24 extends linearly in the axial direction X. Therefore, the air chamber 33 can be large even when the resonator 18 is arranged on the support lining 24.An outer surface of the resonator 18, which faces the upstream region R1, can have such a streamlined shape that its diameter gradually decreases in the axial direction X to both sides.

[0041] Fig. 7A is a perspective view, a modified example of the one in Fig. 3 shown resonator 18. Fig. 7B is a sectional view along line VIIB-VIIB of Fig. 7A. Fig. 7C is a sectional view along line VIIC-VIIC of Fig. 7A. As in the Fig. As shown in Figures 7A to 7C, the resonator 18 can contain a partition plate 44 that divides the resonance chamber 43 into cavities 45. The cavities 45 are connected to the respective openings 41.

[0042] The partition plate 44 divides the resonance chamber 43 both in the axial direction X and in the circumferential direction Z. Specifically, the partition plate 44 comprises parts extending in the axial direction X and parts extending in the circumferential direction Z. An opening 41 can be connected to a cavity 45, or the openings 41 can be connected to a cavity 45. In a development view from the radial direction Y, the partition plate 44 can have a shape such that each cavity 45 has a polygonal shape (e.g., a square or a hexagonal shape) or a circular shape.

[0043] Accordingly, even if sound pressures with opposite phases are distributed in both the axial direction X and the circumferential direction Z, mutual interference between these opposing sound pressures is prevented. Therefore, a reduction in the resonance volume due to sound pressure interference can be prevented, and a resonance at a specific frequency can be generated.

[0044] Fig. 8A is a main component sectional view, which is a first modified example of the in Fig. Combustion chamber 4 is shown in section 3. As in Fig. As shown in Figure 8A, in a combustion chamber 104 of the first modified example, a resonator 118 projects further towards the downstream region R3 than a portion of the support lining 24 that borders the resonator 18 in the axial direction X. More precisely, an inner circumferential surface of the resonator 118 is located in the radial direction Y within an inner circumferential surface of the section of the support lining 24 that borders the resonator 18 in the axial direction X. In the present embodiment, a resonator main body 150, which is fitted internally into the support lining 24, is arranged such that it projects from the support lining 24 towards the downstream region R3. For example, the outer circumferential surface of the support lining 24 can extend linearly in the axial direction X.Therefore, even when the resonator 118 is located at the support lining 24, a narrowing of the upstream region R1 can be prevented. The resonator can be positioned in an intermediate position between the position of the in . Fig. 3 shown resonator 18 and the position of the in Fig. Resonator 118 is shown in 8A.

[0045] Fig. 8B is a principal component section view, which is a second modified example of the one in Fig. Combustion chamber 4 is shown in section 3. As in Fig. As shown in Figure 8B, in a combustion chamber 204 of the second modified example, the resonator 18 is the same as in the embodiment above, but a tubular casing 221 differs from that in the embodiment above. The tubular casing 221 includes a swelling section 221a located opposite the resonator 18 in the radial direction Y, and the diameter of this section increases outwards in the radial direction Y. This prevents a section of the upstream region R1, located outside the resonator 18 in the radial direction Y, from constricting.

[0046] Fig. 8C is a principal component section view, which is a third modified example of the one in Fig. Combustion chamber 4 is shown in section 3. As in Fig. As shown in Figure 8C, in a combustion chamber 304 of the third modified example, a resonator 318 (third resonator) projects from the outside of the tubular housing 21. The resonator 318 comprises a resonator main body 350, which is connected to the outer circumferential surface of the support lining 24. The resonator main body 350 comprises: a hollow section 350a, which defines a resonance chamber 343, and tubular sections 350b, which project inwards in the radial direction Y from the resonator main body 350.

[0047] The hollow section 350a is located radially Y outside the outer casing tube 21. The outer casing tube 21 and the resonator main body 350 are in contact at Fig. 8C, but do not need to touch. The pipe sections 350b penetrate the outer casing 21 in radial direction Y, cross the upstream region R1 in radial direction, and are connected to the support lining 24. The support lining 24 contains through-holes located on its inner circumferential surface, forming the openings 41 facing the downstream region R3. The interiors of the pipe sections 350b are connected to these through-holes. More precisely, the interior of the pipe section 350b and the through-hole of the support lining 24 form a choke 342. This allows the degrees of freedom of the volume of the resonance chamber 343 to be increased and the degrees of freedom for adjusting the frequency to be damped to be improved. For example, the resonance chamber 343 is enlarged, and the low-frequency vibrations can be reduced. Design 2

[0048] Fig. Figure 9 is a main component sectional view of a combustion chamber 404 of embodiment 2. As in Fig. As shown in Figure 9, a resonator 418 (second resonator) is located in the combustion chamber 404 at an end plate 422 of a housing 411. The end plate 422 contains a recess 422a, which is opposite the air chamber 33 and extends annularly around the axis C. The resonator 418 is housed in the recess 422a. The resonator 418 is a hollow element with an annular shape similar to the recess 422a.

[0049] The resonator 418 comprises openings 441, chokes 442, and a resonance chamber 443. The resonance chamber 443 is an annular cavity of the resonator 418. The walls of the resonator 418 can be partially omitted, and the resonance chamber 443 can be defined by using a surface of the end plate 422. The openings 441 are located on a surface of the resonator 418 opposite the air chamber 33 and are arranged at intervals in one direction around the axis C. The chokes 442 are through holes located on a wall of the resonator 418 opposite the air chamber 33 and connect the openings 441 to the resonance chamber 443.

[0050] The openings 441 of the resonator 418 face directly towards and are open to the air chamber 33. The openings 441 are connected to the direction change area R2. The openings 441 are located on the inside of the air inlet openings 35 in the radial direction Y and are open towards the direction change area R2. The openings 441 are open in the axial direction X, so that they face the combustion chamber 31. In particular, one axis of each opening 441 is substantially parallel to the axis C. One axis of each throttle 442 extends in the axial direction X.

[0051] The area of ​​the passage section of the air duct 16, which is orthogonal to the axial direction X, changes at the virtual interface M, and the pressure waves are partially reflected or canceled out on a downstream side of the virtual interface M. Therefore, if the openings 441 of the resonator 418 are open in the direction of the direction change region R2, the pressure waves can be effectively absorbed. Since the openings 441 point in the axial direction X, the pressure waves transmitted in the axial direction X from the combustion chamber 31 can also be effectively absorbed. Only the resonator 418 can be arranged at the combustion chamber 404, but the resonator 18 of embodiment 1 (or one of the resonators 118, 218, and 318 of the first to fourth modified examples) can also be used. Since the other components are the same as in embodiment 1, their description is omitted.

[0052] Fig. 10A is a perspective view, a modified example of the one in Fig. 9 shows resonator 418. Fig. 10B is a section view along the XB-XB line of Fig. 10A. As in Fig. 10A and Fig. As shown in Figure 10B, the resonator 418 can contain a partition plate 444 that divides the resonance chamber 443 into cavities 445. The cavities 445 are connected to the respective openings 441.

[0053] The partition plate 444 divides the resonance chamber 443 in the circumferential direction Z. An opening 441 can be connected to a cavity 445, or the openings 441 can be connected to a cavity 445. The partition plate 444 can be shaped such that each cavity 445 has a fan shape when viewed from the axial direction X.

[0054] Accordingly, even with a distribution of sound pressures whose phases are opposite in the circumferential direction Z, mutual interference of the sound pressures with opposite phases is prevented. Therefore, the reduction of the resonance volume due to interference of the sound pressures can be prevented, and resonance at a specific frequency can be generated. Each cavity 445 can have such a shape that it is further subdivided in the radial direction. Even if there is a distribution of sound pressures whose phases are opposite in the radial direction Y, the interference of the sound pressures with opposite phases is prevented by subdividing each cavity 445 in the radial direction Y.

[0055] Fig. 11A is a principal component section view, which is a first modified example of the in Fig. Combustion chamber 404 is shown in section 9. As in Fig. As shown in Figure 11A, in the combustion chamber 504 of the first modified example, a resonator 518 projects in the axial direction X from an end plate 522 into the air chamber 33. The shape of the resonator 518 itself is the same as that of the resonator 418. Therefore, a local reduction in the thickness of the end plate 522 can be mitigated. The entire resonator 518 can be located on the second side of the end plate 522 in the axial direction X, i.e., the entire resonator 518 can be located within the air chamber 33.

[0056] Fig. 11B is a principal component section view, which is a second modified example of the one in Fig. Combustion chamber 404 is shown in section 9. As in Fig. As shown in Figure 11B, in a combustion chamber 604 of the second modified example, a resonator 618 (third resonator) projects to the outside of an end plate 622. The resonator 618 comprises a resonator main body 650, which is connected to an outer surface of the end plate 622. The resonator main body 650 is located outside the housing 11 and defines a resonance chamber 643 within it. The resonator main body 650 and the end plate 622 are in contact at Fig. 11B, but do not need to touch. The end plate 622 contains a through-hole that is connected to the resonance chamber 643 and extends in the axial direction X.

[0057] The through-hole of the end plate 622 forms a choke 642. A wall (forming part of the choke 642) of the resonator main body 650, which is in surface contact with the end plate 622, can be omitted. Furthermore, the resonator main body 650 does not need to be in surface contact with the end plate 622. The end plate 622 has an opening 641 located on a surface bounding the air chamber 33 (surface on the side on the axially X side) and serves as the inlet of the choke 642. This allows the degree of freedom of the volume of the resonance chamber 643 to be increased and the degree of freedom for adjusting the frequency to be damped to be improved. For example, the resonance chamber 643 can be enlarged, and the low-frequency vibrations can be reduced. embodiment 3

[0058] Fig. Figure 12 is a main component sectional view of a combustion chamber 704 of embodiment 3. As shown in Fig. As shown in Figure 12, the combustion chamber 704 comprises resonators 718A and 718B, which are open towards a portion of the direction change region R2 located outside the air inlet openings 35 in the radial direction Y. Resonator 718A is located on a tubular housing 721. An opening 741A of resonator 718A is located outside the direction change region R2 in the radial direction Y and is open inwards in the radial direction Y. Resonator 718B is located on an end plate 722. An opening 741B of resonator 718B is located on the first side of the direction change region R2 in the axial direction X and is open to the second side in the axial direction X. The combustion chamber 704 may further include resonator 18 of embodiment 1 and resonator 418 of embodiment 2. Since the other components are the same as those in embodiment 1, their explanation is omitted.

[0059] Fig. Figures 13A to 13C are schematic representations showing variations of the air duct 16 of the combustion chamber 4. For clarity, the same reference numerals are used for the corresponding components in the present variants as for the components in embodiment 1, even though the shapes of the components differ.

[0060] In Fig. In 13A, the housing 11 is configured such that each of the upstream regions R1, the direction change region R2, and the downstream region R3 has an annular shape extending around the axis of the tubular body 12. Fig. In 13B, the tubular body 12 is covered with a guide element 19, which is housed in a casing (not shown). The guide element 19 is configured such that the upstream region R1, the direction change region R2, and the downstream region R3 each have an annular shape extending around the axis of the tubular body 12. Fig. 13C the sheathing 11 is configured such that the direction change region R2 has a column-like shape around the axis of the tubular body 12; and each of the upstream regions R1 and the downstream regions R3 has an annular shape extending around the axis of the tubular body 12.

[0061] In the Fig. In 13A to 13C, the virtual boundary plane M between the upstream region R1 and the direction-change region R2 is a virtual plane that: passes through the end E, located on the second side in the axial direction X, of a section of the air duct 16 extending in the radial direction Y to connect the upstream region R1 with the downstream region R3; and is orthogonal to the axial direction X. The area of ​​the section of the air duct 16 that is orthogonal to the axial direction X changes at the virtual boundary plane M, and the openings of a resonator (not shown) are open to a space of the air duct 16 located downstream of the virtual boundary plane M. Design 4

[0062] Fig. Figure 14 is a main component sectional view of a combustion chamber 804 of embodiment 4. As shown in Fig. As shown in Figure 14, a resonator 818 is located in the combustion chamber 804 on a tubular body 812 (in particular a support lining 824) and is open towards the downstream region R3. The tubular body 812 contains leakage openings 812a through which a resonance chamber 843 of the resonator 818 communicates with the upstream region R1. The leakage openings 812a are located on the second side of the direction-change region R2 in the axial direction X. The leakage openings 812a ensure that the downstream region R3 communicates with the upstream region R1 through the resonator 818 without the direction-change region R2.

[0063] The diameter of each leak hole 812a is not less than 0.1 mm and not greater than 10 mm. The diameter of the leak hole 812a is smaller than the diameter of an opening 841 of the resonator 818 and the diameter of a throttle 842 of the resonator 818. In particular, the diameter of the leak hole 812a cannot be less than 1 / 10 of the height of the leak hole 812a (i.e., the length of a passage axis of the leak hole 812a). Therefore, the pressure waves can be effectively reduced while simultaneously improving the machinability by a laser or similar device. Furthermore, the total opening area of ​​the leak holes 812a must not exceed half the cross-sectional area of ​​a plane of the upstream region R1 that is perpendicular to the flow direction. The leak holes 812a can transmit sound energy from the downstream region R3 to the upstream region R1.Therefore, the vibrations generated by combustion can be further effectively reduced. Since the other components are the same as in embodiment 1, further explanations are omitted.

[0064] The in Fig. The resonator 818 shown in Figure 14 is similar to the one in Fig. The resonator 118 shown in 8A can also be used in the Fig. 3 shown resonator 18 or the one in Fig. The resonator shown in 8C may be similar to 318. If the Fig. 14 shown resonator 818 the in Fig. Similar to the resonator 318 shown in Figure 8C, the leak holes 812a may be located on the support lining 24 or the pipe section 350b. Design 5

[0065] Fig. Figure 15 is a main component sectional view of a combustion chamber 904 of embodiment 5. As shown in Fig.As shown in Figure 15, the combustion chamber 904 does not contain a resonator. A tubular body 912 (in particular a support lining 924) contains leakage holes 912a that connect the downstream region R3 with the upstream region R1. The leakage holes 912a are located on the second side of the direction change region R2 in the axial direction X. The leakage holes 912a ensure that the downstream region R3 is connected to the upstream region R1 without passing through the direction change region R2.

[0066] The diameter of each leak hole 912a is not less than 0.1 mm and not more than 10 mm. In particular, the diameter of the leak hole 912a cannot be less than 1 / 10 of the height of the leak hole 912a (i.e., the length of the passage axis of the leak hole 912a). Therefore, the pressure waves can be effectively reduced while simultaneously improving machinability with a laser or similar device. Furthermore, the total opening area of ​​the leak holes 912a must not exceed half the cross-sectional area of ​​a plane of the upstream region R1 that is perpendicular to the flow direction. The leak holes 912a can transfer the sound energy from the downstream region R3 to the upstream region R1. Therefore, the vibrations generated by combustion can be effectively reduced even without a resonator. Since the other components are the same as in embodiment 1, further explanations are omitted.

[0067] The embodiments and modified examples described above serve as examples of the technology disclosed in this application. However, the technology in this disclosure is not limited to these and is applicable to embodiments in which modifications, substitutions, additions, omissions, and the like have been appropriately made. Furthermore, a new embodiment can be produced by combining the components described in the embodiments above with the modified examples above. For example, some of the components or methods of one embodiment or modified example can be applied to another embodiment or modified example.Some components of an embodiment or a modified example can be separated from the other components of the embodiment or the modified example and arbitrarily extracted. Furthermore, the components shown in the accompanying drawings and detailed explanations include not only components that are essential for solving the problems, but also components that serve to illustrate the technology described above and are not essential for solving the problems.

[0068] The following aspects reveal preferred embodiments. First aspect

[0069] A gas turbine combustion chamber, comprising: a tubular body that defines a combustion chamber, extends from a first side to a second side in an axial direction, and defines an outlet opening located on the second side in the axial direction; an air duct through which air is supplied to the combustion chamber; and at least one resonator with at least one opening that is open to the air duct and a resonance chamber that is connected to the opening, wherein: the air passage includes an upstream area extending along an outer circumferential surface of the tubular body, a downstream area extending along an inner circumferential surface of the tubular body, located on the first side of the combustion chamber in the axial direction and connected to the combustion chamber, and a direction change region that connects the upstream region with the downstream region in a radial direction of the tubular body and adjoins the upstream region, such that an area of ​​a section of the air duct, which is orthogonal to the axial direction, changes at a position between the upstream region and the direction change region; and wherein the opening of the resonator is open to a space of the air duct which is located downstream of the upstream area. Second aspect

[0070] The gas turbine combustion chamber according to the first aspect, wherein: which contains at least one resonator, a first resonator; and the opening of the first resonator is open towards the downstream area of ​​the air duct. Third aspect

[0071] The gas turbine combustion chamber according to the second aspect, wherein the first resonator is arranged on the tubular body. Fourth aspect

[0072] The gas turbine combustion chamber according to the third aspect, wherein an outer circumferential surface of the first resonator is located in a radial direction outside an outer circumferential surface of a part of the tubular body that is adjacent to the first resonator in an axial direction. Fifth aspect

[0073] The gas turbine combustion chamber according to the third or fourth aspect, wherein an inner circumferential surface of the first resonator is arranged in the radial direction within an inner circumferential surface of a part of the tubular body which adjoins the first resonator in the axial direction. Sixth aspect

[0074] The gas turbine combustion chamber according to one of the first to fifth aspects, whereby: which contains at least one resonator and a second resonator; and the opening of the second resonator is open in the direction of the direction change region. Seventh aspect

[0075] The gas turbine combustion chamber according to the sixth aspect, further comprising an end plate arranged axially on the first side of the tubular body and having an inner surface facing the air duct, wherein the second resonator is located at the end plate. Eighth aspect

[0076] The gas turbine combustion chamber according to one of the first to seventh aspects, which further comprises a casing that accommodates the tubular body, wherein: an air inlet duct, encompassing the upstream area, is arranged between the housing and the tubular body; wherein the tubular body comprises a first lining that limits the combustion chamber and a second lining that abuts the first lining in an axial direction on the first side and defines an air chamber that encloses the downstream area; and The opening of at least one resonator is open to the air chamber. Ninth aspect

[0077] The gas turbine combustion chamber according to one of the first to eighth aspects, which further includes a guide plate having a guide hole and dividing the downstream space of the upstream area of ​​the air duct into a space before the guide and a space after the guide, wherein The opening of at least one resonator is open towards the message space. Tenth aspect

[0078] The gas turbine combustion chamber according to one of the first to ninth aspects, wherein the resonance chamber of the at least one resonator is located outside the casing. Eleventh aspect

[0079] The gas turbine combustion chamber according to one of the first to tenth aspects, whereby: which has at least one opening, or openings arranged in the axial direction and in a circumferential direction extending around the axial direction; and which contains at least one resonator, a partition plate that divides the resonance chamber into cavities that are connected to the respective openings, and that divides the resonance chamber in a circumferential direction. Twelfth aspect

[0080] The gas turbine combustion chamber according to the eleventh aspect, wherein the partition plate further divides the resonance chamber in an axial or radial direction. Fourteenth aspect

[0081] The gas turbine combustion chamber according to one of the first to twelfth aspects, wherein the tubular body has a leakage hole connecting the downstream area with the upstream area excluding the direction change area. Fifteenth aspect

[0082] A gas turbine combustion chamber, including: a tubular body defining a combustion chamber, extending from a first side to a second side in an axial direction and defining an exhaust opening located on the second side in the axial direction; and an air duct through which air is supplied to the combustion chamber, wherein: the air passage includes an upstream area extending along an outer circumferential surface of the tubular body, a downstream area extending along an inner circumferential surface of the tubular body, located on the first side of the combustion chamber in the axial direction and connected to the combustion chamber, and a direction change region that connects the upstream region with the downstream region in a radial direction of the tubular body; and The tubular body has a leakage hole that connects the downstream area with the upstream area without passing through the direction change area. Reference character list 1 gas turbine 4 Combustion chamber 11 cases 12 tubular bodies 13 Injector nozzle 16 Air passage or duct 17 guide plate 17a Directional hole 18 Resonator 21 tubular housing 22 End plate 23 Combustion or combustion lining (first insert or lining) 24 Support lining (second insert or lining) 31 Combustion chamber 32 Outlet opening 33b Room after the judgment or message room 33 air chamber 33a Room in front of the straightening room or preparation room 34 Air intake duct 35 Air intake opening 41 Opening 42 Throttle or restrictor 43 Resonance chamber 44 Dividing plate 45 cavity A air C axis E End Fuel G Combustion gas M, N virtual boundary plane R1 upstream or upstream area R2 area with change of direction or change of direction area R3 downstream or downstream area X axial direction Y radial direction Z circumferential direction

Claims

[1] Gas turbine combustor, comprising: a tubular body defining a combustion chamber, extending from a first side to a second side in an axial direction, and defining an exhaust port located on the second side in the axial direction; an air passage through which air is supplied to the combustion chamber; and at least one resonator with at least one opening open to the air passage, and a resonance chamber communicating with the opening, wherein: the air passage includes an upstream region extending along an outer peripheral surface of the tubular body, a downstream portion extending along an inner peripheral surface of the tubular body, disposed on the first side of the combustion chamber in the axial direction, and communicating with the combustion chamber, and a direction change portion connecting the upstream portion to the downstream portion in a radial direction of the tubular body and adjacent to the upstream portion, so that an area of ​​a section of the air passage orthogonal to the axial direction changes at a position between the upstream portion and the direction change portion; and the opening of the resonator is open to a space of the air duct located downstream of the upstream region. [2] Gas turbine combustor according to claim 1, wherein: the at least one resonator comprises a first resonator; and the opening of the first resonator is open towards the downstream region of the air duct. [3] A gas turbine combustor according to claim 2, wherein the first resonator is arranged on the tubular body. [4] A gas turbine combustor according to claim 3, wherein an outer peripheral surface of the first resonator is located radially outside an outer peripheral surface of a part of the tubular body which is adjacent to the first resonator in the axial direction. [5] A gas turbine combustor according to claim 3 or 4, wherein an inner peripheral surface of the first resonator is disposed in the radial direction inside an inner peripheral surface of a part of the tubular body adjacent to the first resonator in the axial direction. [6] Gas turbine combustor according to one of claims 1 to 4, wherein: the at least one resonator comprises a second resonator; and the opening of the second resonator is open in the direction of the direction change region. [7] A gas turbine combustor according to claim 6, further comprising an end plate disposed on the first side of the tubular body in the axial direction and having an inner surface facing the air passage, the second resonator being located on the end plate. [8] A gas turbine combustor according to any one of claims 1 to 4, further comprising a casing accommodating the tubular body, wherein: an air inlet duct comprising the upstream region is arranged between the housing and the tubular body; the tubular body comprises a first lining that defines the combustion chamber and a second liner axially adjacent to the first liner on the first side and defining an air chamber encompassing the downstream region; and the opening of at least one resonator is open towards the air chamber. [9] A gas turbine combustor according to any one of claims 1 to 4, further comprising a directional plate having a directional hole and dividing the space of the air duct downstream of the upstream region into a directional space and a message space, the opening of the at least one resonator being open to the message space. [10] Gas turbine combustion chamber according to one of claims 1 to 4, wherein the resonance chamber of the at least one resonator is arranged outside the housing. [11] Gas turbine combustor according to one of claims 1 to 4, wherein: the at least one opening has openings arranged in a row in the axial direction and in a circumferential direction extending around the axial direction; and the at least one resonator includes a partition plate which divides the resonance chamber into cavities communicating with the respective openings and which divides the resonance chamber in the circumferential direction. [12] A gas turbine combustor according to claim 11, wherein the partition plate further divides the resonance chamber in an axial or radial direction. [13] A gas turbine combustor according to any one of claims 1 to 4, wherein the tubular body has a leak hole that communicates the downstream region with the upstream region without passing through the direction change region. [14] Gas turbine combustor, comprising: a tubular body defining a combustion chamber, extending from a first side to a second side in an axial direction, and defining an exhaust port located on the second side in the axial direction; and an air passage or channel through which air is supplied to the combustion chamber, whereby: the air passage includes an upstream region extending along an outer peripheral surface of the tubular body, a downstream portion extending along an inner peripheral surface of the tubular body, disposed on the first side of the combustion chamber in the axial direction, and communicating with the combustion chamber, and a direction change portion connecting the upstream portion to the downstream portion in a radial direction of the tubular body; and the tubular body has a leak hole connecting the downstream region to the upstream region without passing through the direction change region or without passing through the direction change region.