Burner assembly, gas turbine combustor, and gas turbine

Abstract

In a burner assembly according to at least one embodiment of the present invention, each of a plurality of burners is provided with a flow path through which air can flow. The flow path includes: a first region in which fuel injection holes are formed; and a second region which is a region downstream of the first region and in which the fuel injected from the injection hole is mixed with air. The first region extends from an upstream-side end of the flow path to a connection position with the second region, and an injection hole is formed at a position closer to the connection position than the upstream-side end. The first region has: at least one protrusion protruding inward in the radial direction of the flow path and having an injection hole formed therein; and at least one peripheral wall part which is adjacent to the at least one protrusion in the circumferential direction of the flow path and is not provided with a protrusion. A second cross-sectional area in the second region is smaller than a first cross-sectional area in the first region with respect to a cross-sectional area of the flow path.

Description

Technical Field

[0001] The present invention relates to a burner assembly, a gas turbine combustor and a gas turbine.

[0002] This application claims priority based on Japanese Patent Application No. 2023-053155 filed with the Japan Patent Office on March 29, 2023, and uses the contents thereof herein. Background Art

[0003] As a technology for achieving flashback resistance against fuels with a high risk of flashback (such as hydrogen) and reducing NOx, there is a technology for forming a plurality of independent short flames using a burner assembly (cluster burner).

[0004] In this technology, a plurality of mixing flow paths for mixing fuel and air are arranged to reduce the scale of fuel mixing, thereby achieving high mixing performance even without actively utilizing swirling flow in mixing fuel and air.

[0005] Patent Document 1 discloses a burner assembly for achieving low NOx emissions and suppressing flashback. Each burner in this burner assembly includes a fuel nozzle and a mixing flow path through which fuel and air flow. The fuel nozzle includes a protrusion that projects upstream of the inlet of the mixing flow path in the direction of air flow. Furthermore, fuel injection holes are formed on the side of the protrusion. Fuel injected from the fuel injection holes flows into the inlet of the mixing flow path along with air, thereby mixing the fuel and air.

[0006] Previous technical literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2019-168198 Summary of the Invention

[0009] Technical issues to be solved by the invention

[0010] The burner assembly described in Patent Document 1 has room for further improvement from the viewpoint of suppressing flashback.

[0011] In view of the above-described circumstances, at least one embodiment of the present invention has an object to provide a burner assembly, a gas turbine combustor, and a gas turbine capable of suppressing flashback.

[0012] Means for solving technical problems

[0013] (1) A burner assembly according to at least one embodiment of the present invention includes a plurality of burners for mixing fuel and air, wherein:

[0014] Each of the plurality of burners includes a flow path through which the air can flow.

[0015] The flow path includes:

[0016] a first region which is a region on the upstream side of the flow of the air and in which the injection hole of the fuel is formed; and

[0017] The second region is a region on the downstream side of the first region and is where the fuel injected from the injection hole mixes with the air.

[0018] Regarding the first area,

[0019] extending from the upstream end of the flow path to a connection position with the second region,

[0020] The injection hole is formed at a position closer to the connection position than the upstream end portion.

[0021] have:

[0022] at least one protrusion protruding radially inward of the flow path and having the injection hole formed therein; and

[0023] at least one peripheral wall portion is adjacent to the at least one protrusion in the circumferential direction of the flow path and is not provided with the protrusion;

[0024] Regarding the cross-sectional area of ​​the flow path when viewed in the extending direction of the flow path, the second cross-sectional area in the second region is smaller than the first cross-sectional area in the first region.

[0025] (2) A gas turbine combustor according to at least one embodiment of the present invention includes:

[0026] A burner assembly having the structure of (1) above; and

[0027] The combustion tube forms a space for forming flames on the downstream side of the burner assembly.

[0028] (3) A gas turbine according to at least one embodiment of the present invention includes:

[0029] compressor;

[0030] a gas turbine combustor configured to be supplied with air compressed by the compressor and fuel, and to combust the fuel to generate combustion gas; and

[0031] a turbine driven by said combustion gases produced in said gas turbine combustor,

[0032] The gas turbine combustor is a gas turbine combustor having the structure of (2) above.

[0033] Effects of the Invention

[0034] According to at least one embodiment of the present invention, a burner assembly, a gas turbine combustor, and a gas turbine capable of suppressing flashback can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic configuration diagram of a gas turbine according to one embodiment.

[0036] Figure 2 It is a cross-sectional view showing the vicinity of the burner.

[0037] Figure 3 It is a perspective view for explaining the structure of a burner.

[0038] Figure 4 This is a partial schematic perspective view showing a part of a burner assembly according to one embodiment.

[0039] Figure 5 This is a part of the burner assembly involved in one embodiment. Figure 4 The VV-direction sectional view is equivalent to the figure.

[0040] Figure 6 Yes Figure 5 A schematic diagram of a portion of the cross section viewed in the direction VI-VI.

[0041] Figure 7 This is a partial schematic perspective view showing a portion of a burner assembly according to one embodiment, and shows a state in which an inlet flow path wall is removed for illustration.

[0042] Figure 8 This is a schematic diagram of a portion of the burner assembly, with the inlet flow path wall removed for illustration, as viewed along the central axis from the upstream side in the air flow direction.

[0043] Figure 9 Yes Figure 8 A schematic diagram of a portion of the cross section taken along the line IX-IX.

[0044] Figure 10 Yes Figure 8 A schematic diagram of a portion of the cross section viewed along the XX direction.

[0045] Figure 11 A part of a burner assembly according to another embodiment Figure 4 The VV-direction sectional view is equivalent to the figure.

[0046] Figure 12 Yes Figure 11A schematic diagram of a portion of the cross section viewed in the direction XII-XII.

[0047] Figure 13 It is viewed from the upstream side of the air flow direction. Figure 6 A cross-sectional view of part XIII surrounded by a dotted line.

[0048] Figure 14 When viewed from the upstream side of the air flow direction Figure 6 The figure corresponds to the cross-sectional view of the portion XIII surrounded by the dotted line, and shows another example of the protrusion.

[0049] Figure 15 These are diagrams for explaining the dimensions of various parts of the burner assembly according to several embodiments.

[0050] Figure 16 These are diagrams for explaining the dimensions of various parts of the burner assembly according to several embodiments.

[0051] Figure 17 It is a diagram for explaining changes in the shape of the protrusion.

[0052] Figure 18 It is viewed from the upstream side of the air flow direction. Figure 17 A cross-sectional view of part XVIII surrounded by a dotted line.

[0053] Figure 19 It is observed from the upstream side of the air flow direction. Figure 17 The figure corresponding to the cross-sectional view of the portion XVIII surrounded by the dotted line shows another example.

[0054] Figure 20 It is a diagram for explaining changes in the shape of the protrusion.

[0055] Figure 21 It is viewed from the upstream side of the air flow direction. Figure 20 A cross-sectional view of the XXI portion surrounded by a dotted line.

[0056] Figure 22 These are diagrams for explaining the introduction flow path wall and modifications of the flow path wall.

[0057] Figure 23 This is a schematic diagram for explaining the extending direction of the fuel injection hole, and shows a cross section perpendicular to the central axis.

[0058] Figure 24 This is a schematic diagram for explaining the extending direction of the fuel injection hole, and shows a cross section perpendicular to the central axis.

[0059] Figure 25This is a diagram showing another example of a protrusion of a fuel nozzle. Figure 5 The sectional view taken along the XXV-XXV arrow is equivalent to FIG.

[0060] Figure 26 This is a schematic diagram of a portion of the burner assembly according to a modified example of the first region as viewed along the central axis L from the upstream side in the air flow direction.

[0061] Figure 27 This is a schematic cross-sectional view of the first region as viewed in a cross section including the central axis of the flow path.

[0062] Figure 28 This is a schematic cross-sectional view of the first region as viewed in a cross section including the central axis of the flow path.

[0063] Figure 29 This is a schematic cross-sectional view of the first region as viewed in a cross section including the central axis of the flow path.

[0064] Figure 30A Yes Figure 26 Schematic cross-sectional view of section AA in FIG.

[0065] Figure 30B Yes Figure 26 Schematic cross-sectional view of section BB in FIG.

[0066] Figure 31A Yes Figure 26 Schematic cross-sectional view of section AA in FIG.

[0067] Figure 31B Yes Figure 26 Schematic cross-sectional view of section BB in FIG.

[0068] Figure 32A Yes Figure 26 Schematic cross-sectional view of section AA in FIG.

[0069] Figure 32B Yes Figure 26 Schematic cross-sectional view of section BB in FIG.

[0070] Figure 33A Yes Figure 26 Schematic cross-sectional view of section AA in FIG.

[0071] Figure 33B Yes Figure 26 Schematic cross-sectional view of section BB in FIG.

[0072] Figure 34A Yes Figure 26 Schematic cross-sectional view of section AA in FIG.

[0073] Figure 34B Yes Figure 26 Schematic cross-sectional view of section BB in FIG.

[0074] Figure 35A Yes Figure 26 Schematic cross-sectional view of section AA in FIG.

[0075] Figure 35B Yes Figure 26 Schematic cross-sectional view of section BB in FIG. DETAILED DESCRIPTION

[0076] Several embodiments of the present invention are described below with reference to the accompanying drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in the embodiments or shown in the drawings are not intended to limit the scope of the present invention and are merely illustrative examples.

[0077] For example, expressions such as "in a certain direction", "along a certain direction", "parallel", "orthogonal", "center", "concentric" or "coaxial" that indicate relative or absolute configurations not only strictly indicate such configurations, but also indicate a state of relative displacement at an angle or distance with a tolerance or a degree that can achieve the same function.

[0078] For example, expressions such as “same,” “equal,” and “homogeneous” indicating that things are in an equal state not only refer to a strictly equal state but also refer to a state in which there is a tolerance or a degree of difference to achieve the same function.

[0079] For example, expressions indicating shapes such as a quadrilateral or a cylinder not only indicate shapes such as a quadrilateral or a cylinder in a strict geometric sense, but also indicate shapes including concave and convex portions or chamfered portions as long as the same effect can be obtained.

[0080] On the other hand, the expression “having”, “including” or “having” a constituent element is not an exclusive expression that excludes the existence of other constituent elements.

[0081] First, refer to Figure 1 A gas turbine will be described as an example of an application target of the burners and combustors according to some embodiments. Figure 1 This is a schematic diagram of the structure of a gas turbine according to one embodiment. Figure 1 As shown, the gas turbine 1 includes a compressor 2 for generating compressed air, a combustor 4 for generating combustion gas using the compressed air and fuel, and a turbine 6 configured to be rotationally driven by the combustion gas. In the case of a power generation gas turbine 1, a generator (not shown) is connected to the turbine 6.

[0082] The compressor 2 includes a plurality of stationary blades 16 fixed to the compressor chamber 10 and a plurality of moving blades 18 implanted on the rotor 8 so as to be alternately arranged with respect to the stationary blades 16 .

[0083] The air taken in from the air intake 12 is fed into the compressor 2 , and the air is compressed by the plurality of stationary blades 16 and the plurality of moving blades 18 , thereby becoming high-temperature and high-pressure compressed air.

[0084] The fuel and the compressed air generated in the compressor 2 are supplied to the combustor 4, and the fuel is burned in the combustor 4 to generate combustion gas as the working fluid of the turbine 6. Figure 1 As shown, the gas turbine 1 includes a plurality of combustors 4 arranged in a circumferential direction around a rotor 8 in a casing 20 .

[0085] The turbine 6 includes a plurality of stationary blades 24 and moving blades 26 disposed in a combustion gas passage formed by a turbine chamber 22. The stationary blades 24 and moving blades 26 of the turbine 6 are disposed downstream of the combustor 4 with respect to the flow of the combustion gas.

[0086] The stationary blades 24 are fixed to the turbine housing 22. A plurality of the stationary blades 24 arranged along the circumferential direction of the rotor 8 form a stationary blade row. Furthermore, the moving blades 26 are implanted on the rotor 8. A plurality of the moving blades 26 arranged along the circumferential direction of the rotor 8 form a moving blade row. The stationary blade rows and the moving blade rows are alternately arranged in the axial direction of the rotor 8.

[0087] In turbine 6, combustion gas from combustor 4 flows into the combustion gas passage and passes through multiple stationary blades 24 and multiple moving blades 26, thereby rotating rotor 8. This drives a generator connected to rotor 8, generating electricity. The combustion gas that has driven turbine 6 is discharged to the outside through exhaust chamber 30.

[0088] Figure 2 It is a cross-sectional view showing the vicinity of the burner 4 . Figure 3 This is a perspective view for explaining the structure of the burner 4. The burner 4 includes a burner assembly 32, a bottomed cylindrical housing 20 that accommodates the burner assembly 32, and a combustion tube 25 that forms a space for forming flames on the downstream side of the burner assembly 32. Figure 2In the figure, the dashed line represents the common central axis L of the casing 20, the burner assembly 32, and the combustion tube 25. The burner assembly 32 is disposed within the casing 20 of the combustor 4. In the illustrated exemplary embodiment, the burner assembly 32 is held inside a cylindrical member 34 disposed within the casing 20. The cylindrical member 34 is supported on the casing 20 via a plurality of supports 35 spaced apart around the central axis L. An air flow path 36 is formed between the outer circumferential surface of the casing 20 and the cylindrical member 34 (between the casing 20 and the outer circumferential surface of the burner assembly 32), through which compressed air flowing from the engine room 40 flows.

[0089] The compressed air flowing from the engine room 40 into the air flow path 36 passes through the axial gap 23 between the burner assembly 32 and the bottom surface 21 of the housing 20 and flows together with the fuel into a plurality of mixing flow paths 46 (described later) provided in the burner assembly 32. The fuel and air mixed in the burner assembly 32 are ignited by an ignition device (not shown), forming a flame in the combustion tube 25 to generate combustion gas.

[0090] In some embodiments, as described below, the burner assembly 32 includes a plurality of burners 42 for mixing fuel and air. Each combustion furnace 42 includes a flow path 100 for flowing fuel and air, as described below. In some embodiments, for example, Figure 3 As shown, the burner assembly 32 is provided with a plurality of flow paths 100 in a pentagonal area drawn with a two-dot chain line and centered on the central axis L when viewed from the downstream side along the central axis L, and in five areas arranged circumferentially outside the pentagon in a manner corresponding to the respective sides of the pentagon.

[0091] in addition, Figure 3 The arrangement pattern of each flow path 100 shown is an example and is not necessarily limited to the following. Figure 3 The arrangement pattern of each flow path 100 is shown.

[0092] Figure 4 It is a partial schematic perspective view showing a part of the burner assembly 32 according to one embodiment. Figure 5 This is a part of the burner assembly 32 according to one embodiment. Figure 4 The VV-direction sectional view is equivalent to the figure. Figure 6 Yes Figure 5 A schematic diagram of a portion of the cross section viewed in the direction VI-VI. Figure 7 This is a partial schematic perspective view showing a portion of the burner assembly 32 according to one embodiment, and shows a state in which an inlet flow path wall 115 described later is removed for the sake of explanation. Figure 8This is a schematic diagram of a portion of the burner assembly 32 , with the inlet flow path wall 115 removed for illustration, as viewed along the central axis L from the upstream side in the air flow direction. Figure 9 Yes Figure 8 A schematic diagram of a portion of the cross section taken along the line IX-IX. Figure 10 Yes Figure 8 A schematic diagram of a portion of the cross section viewed along the XX direction.

[0093] Figure 11 This is a part of the burner assembly 32 according to another embodiment. Figure 4 The VV-direction sectional view is equivalent to the figure. Figure 12 Yes Figure 11 A schematic diagram of a portion of the cross section viewed in the direction XII-XII. Figure 13 It is viewed from the upstream side of the air flow direction. Figure 6 A cross-sectional view of part XIII surrounded by a dotted line. Figure 14 It is observed from the upstream side of the air flow direction. Figure 6 The figure corresponds to the cross-sectional view of the portion XIII surrounded by the dotted line in FIG. 1 , and shows another example of the protrusion 51 described later.

[0094] For example, Figures 4 to 9 、 Figure 11 、 Figure 12 As shown, the burner assembly 32 includes a plurality of burners 42 for mixing fuel and air.

[0095] The burners 42 according to several embodiments each include a burner for Figure 1 and Figure 2 ) The inlet flow path 110 for introducing the compressed air for combustion to each of the burners 42, the plurality of fuel nozzles 43 for injecting fuel, and the mixing flow path 46 for the fuel injected from the plurality of fuel nozzles 43 and the compressed air supplied from the inlet flow path 110 to flow in. In the illustrated exemplary embodiment, as described later, the first burner 42a (refer to Figure 8 ), each burner 42 includes one inlet flow channel 110, one mixing flow channel 46, and four fuel nozzles 43 arranged around the one mixing flow channel 46. Fuel is injected into the one mixing flow channel 46 from the four surrounding fuel nozzles 43. In other words, four mixing flow channels 46 are arranged around one fuel nozzle 43, and one fuel nozzle 43 injects fuel into the four mixing flow channels 46.

[0096] In each of the burners 42 according to several embodiments, the flow path 100 through which fuel and air flow is passed includes an inlet flow path 110 and a mixing flow path 46 connected to the downstream side of the inlet flow path 110. The inlet flow path 110 and the mixing flow path 46 are connected by an inlet 48 of the mixing flow path 46 (for example, see Figure 6 、 Figure 12 )connect.

[0097] The introduction flow path 110 is the first region 101 in the flow path 100 , and the mixing flow path 46 is the second region 102 in the flow path 100 .

[0098] Each flow path 100 is configured as a through hole extending parallel to each other, and the center axis O of each flow path 100 extends in a direction along the center axis L of the housing 20. In the illustrated exemplary embodiment, the center axis O of each flow path 100 is parallel to the center axis L of the housing 20.

[0099] In the following description of each portion of the flow channel 100 , the radial direction and the circumferential direction centered on the central axis O may be simply referred to as radial direction and circumferential direction.

[0100] (Introduction flow path wall 115)

[0101] For example, Figures 4 to 6 The introduction flow path wall 115 forming the introduction flow path 110 is configured in a circular tubular shape to define the introduction flow path 110 having a circular cross section inside, and functions as a flow rectifying portion for rectifying the air flowing into the mixing flow path 46 .

[0102] And, for example, Figure 11 and Figure 12 The inlet flow path wall 115 forming the inlet flow path 110 is configured in a rectangular tubular shape to define the inlet flow path 110 having a rectangular cross section inside and functions as a flow rectifying portion for rectifying the air flowing into the mixing flow path 46 .

[0103] The following, for example, Figure 6 As shown, any two burners 42 whose mixing flow paths 46 are closest to each other among the plurality of burners 42 are conveniently referred to as the first burner 42a and the second burner 42b. Similarly, the flow path 100 of the first burner 42a is sometimes also referred to as the first flow path 100a, and the flow path 100 of the second burner 42b is sometimes also referred to as the second flow path 100b. The second flow path 100b is the flow path 100 closest to the first flow path 100a.

[0104] like Figures 4 to 6 、 Figure 11 and Figure 12As shown, the inlet flow path wall 115 forming the inlet flow path 110 (110a) of the first burner 42a and the inlet flow path wall 115 forming the inlet flow path 110 (110b) of the second burner 42b share a partition wall portion 118 (118ab) that separates the inlet flow path 110a of the first burner 42a from the inlet flow path 110b of the second burner 42b. Figures 4 to 6 、 Figure 11 and Figure 12 In the illustrated exemplary embodiment, the inlet flow path wall 115 of the inlet flow path 110 shares the partition wall portion 118 between the inlet flow path walls 115 of a plurality of inlet flow paths 110 (four inlet flow paths 110 in the illustrated embodiment) surrounding the inlet flow path 110 .

[0105] And, as Figure 6 and Figure 12 As shown, the thickness t1 of the partition wall portion 118 ( 118 ab ) in the VI-VI cross section and the XII-XII cross section of the burner assembly 32 is constant in the direction along the central axis O of the first burner 42 a .

[0106] (Fuel nozzle 43)

[0107] For example, Figure 9 As shown, each fuel nozzle 43 includes a downstream area in the introduction flow path 110, that is, an inlet 48 of the mixing flow path 46 (for example, refer to Figure 6 ) A protrusion 50 protrudes further upstream in the air flow direction. Furthermore, each fuel nozzle 43 includes a plurality of fuel injection holes 53 formed on the side surface 44 of the protrusion 50. Figure 8 In the illustrated exemplary embodiment, four fuel injection holes 53 are formed on the side surface 44 of the protrusion 50 at positions corresponding to the four flow paths 100 (mixing flow paths 46) surrounding the protrusion 50. As described later, each fuel injection hole 53 may extend in a direction perpendicular to the central axis O so as to inject fuel toward the central axis O of the flow path 100, or may extend in a direction inclined relative to the direction perpendicular to the central axis O.

[0108] like Figure 9 As shown, each fuel nozzle 43 includes a base end portion 431 having the side surface 44 formed parallel to the central axis O, and a front end portion 432 formed from the base end portion 431 toward the upstream side in the air flow direction.

[0109] like Figures 4 to 6 、 Figure 11 and Figure 12 As shown, a portion of the base end portion 431 and the tip end portion 432 of each of the protrusions 50 protrudes radially inward in the introduction flow path 110 in a downstream region in the introduction flow path 110 . Figures 4 to 6 、 Figure 11 and Figure 12 The protrusions 50 shown each have the same shape as a body of rotation centered about an axis parallel to the central axis O.

[0110] exist Figures 4 to 6 、 Figure 11 and Figure 12 In the example shown, a portion of the base end portion 431 and the front end portion 432 of each of the four protrusions 50 arranged so as to surround an inlet flow path 110 when viewed along the center axis O protrudes radially inward of the inlet flow path 110 from a circumferential position every 90 degrees centered on the center axis O.

[0111] Focusing on each of the protrusions 50, Figures 4 to 6 、 Figure 11 and Figure 12 In the illustrated example, each of the protrusions 50 protrudes toward the inside of each of the four introduction flow paths 110 that are arranged so as to surround the periphery of one protrusion 50 .

[0112] exist Figures 4 to 6 、 Figure 11 and Figure 12 In the example shown, among the four protrusions 50 arranged to surround one inlet flow path 110, two protrusions 50 adjacent in the circumferential direction with the central axis O as the center are separated in the circumferential direction toward the protrusion 51 protruding inside the inlet flow path 110. A peripheral wall portion 116 without a protrusion 51 is provided between the two protrusions 51 adjacent in the circumferential direction. That is, Figures 4 to 6 、 Figure 11 and Figure 12 In the illustrated example, at the axial position where the protrusion 51 is provided, the protrusion 51 and the peripheral wall portion 116 are arranged alternately in the circumferential direction.

[0113] For example, Figure 9 As shown, the top surface 54 of the protrusion 50 (the end surface of the protrusion 50 in the direction of the axis O, i.e., the front end of the protrusion 50) includes a convex surface 56. In the exemplary embodiment shown in the figure, the entire top surface 54 of the protrusion 50 is composed of the smoothly curved convex surface 56. The top surface 54 of the protrusion 50 can be formed into a streamlined shape, for example. Variations in the shape of the protrusion 50 will be described later.

[0114] In the burner assembly 32 involved in several embodiments, the protrusion 51 includes a base end portion 431 extending in a straight line along the extension direction of the center axis O in a cross section along the extension direction of the center axis O, and a front end portion 432 formed in a manner such that the protrusion amount toward the radial inside gradually increases toward the base end portion 431 at a position upstream of the base end portion 431.

[0115] This prevents air flow from the front end 432 toward the base end 431 from separating. Consequently, it reduces the risk of formation of a region with low flow velocity and high fuel concentration near the fuel injection hole 53 (near the fuel jet). Consequently, the risk of flashback, or flashback, from the outlet 47 of the mixing flow path 46 can be reduced.

[0116] (Flow path wall 55)

[0117] For example, Figure 8 As shown, the flow path wall 55 forming the mixing flow path 46 is formed in a tubular shape to define the mixing flow path 46 having a circular cross section inside and functions as a mixing tube for mixing fuel and air. Figure 8 As shown, the flow path wall 55 forming the mixing flow path 46 (46a) of the first burner 42a and the flow path wall 55 forming the mixing flow path 46 (46b) of the second burner 42b share a partition wall portion 58 (58ab) that separates the mixing flow path 46a of the first burner 42a from the mixing flow path 46b of the second burner 42b. Figure 8 In the illustrated exemplary embodiment, the flow path walls 55 of the mixing flow path 46 share a partition wall portion 58 between the flow path walls 55 of a plurality of mixing flow paths 46 (four mixing flow paths 46 in the illustrated embodiment) surrounding the mixing flow path 46 .

[0118] And, as Figure 6 and Figure 12 As shown, the thickness t2 of the partition wall portion 58ab in the VI-VI section and the XII-XII section of the burner assembly 32 is constant in the direction along the central axis O of the first burner 42a on the downstream side of the air flow direction of the end portion 61 on the upstream side of the air flow direction of the partition wall portion 58ab. Figure 8 and Figure 11 As shown, the thickness t2 of the partition wall portion 58ab increases as the distance from the partition wall increases. Figure 5 Section VI-IV, Figure 8 CC section and Figure 11 In addition, as Figure 8 As shown, the CC cross section passes through the center C1 of the inlet 48 of the mixing flow path 46a of the first burner 42a and the center C2 of the inlet 48 of the mixing flow path 46b of the second burner 42b and is along the central axis O of the mixing flow path 46 of the first burner 42a. Figure 5 Section VI-IV and Figure 11 The XII-XII section is a section at the same position as the CC section.

[0119] For example, Figure 7As shown, in the burner assembly 32 , the end surface 59 (end surface on the upstream side in the air flow direction) of the partition wall portion 58 that separates the two closest mixing flow paths 46 has a saddle shape.

[0120] In addition, the inlet 48 of the mixing flow path 46 (for example, see Figure 6 、 Figure 12 ) is defined as the boundary position between the inlet flow path wall 115 and the upstream end portion 61 of the partition wall portion 58ab in the flow direction of the air. In addition, when describing the distance in the direction of the central axis O based on the inlet 48 of the mixing flow path 46, the position in the direction of the central axis O of the inlet 48 of the mixing flow path 46 is defined as the position of the boundary position. Figure 6 and Figure 12 The position on the most downstream side is shown.

[0121] like Figure 6 and Figure 12 As shown in FIG. 1 , the thickness t2 of the partition wall portion 58ab in the VI-VI and XII-XII cross sections of the burner assembly 32 decreases toward the upstream side of the air flow direction at the end portion 61 on the upstream side of the air flow direction in the partition wall portion 58ab. Figure 5 Section VI-IV, Figure 8 CC section and Figure 11 In the XII-XII cross section, the end surface 59 on the upstream side in the air flow direction of the partition wall portion 58ab includes a convex curve 60. In the illustrated exemplary embodiment, Figure 5 Section VI-IV, Figure 8 CC section and Figure 11 In the XII-XII cross section, the end face 59 of the partition wall portion 58ab is entirely formed of a smoothly curved convex curve 60. Figure 5 Section VI-IV, Figure 8 CC section and Figure 11 In the XII-XII cross section, the end surface 59 of the partition wall portion 58ab can be formed into a streamlined shape, for example.

[0122] Here, if Figure 8 and Figure 10 As shown, the protrusion 50 of the second fuel nozzle 43b is located across the plane V (reference Figure 10 ) and on the side opposite to the protrusion 50 of the first fuel nozzle 43a.

[0123] like Figure 10As shown, the height H of the partition wall portion 58ab increases as it approaches the protrusion 50 of the first fuel nozzle 43a from the position of the plane V (the position of the CC cross section), and increases as it approaches the protrusion 50 of the second fuel nozzle 43b from the position of the plane V. Figure 10 In the cross section of the burner assembly 32B shown in FIG. 1 , the end surface 59 on the upstream side in the air flow direction of the partition wall portion 58 ab includes a concave curve 62 connecting the side surface 44 of the protrusion 50 of the first fuel nozzle 43 a and the side surface 44 of the protrusion 50 of the second fuel nozzle 43 b. Figure 11 As shown, the XX section is connected to the inlet 48 of the mixing flow path 46a connected to the first burner 42a (refer to Figure 6 ) and the center C2 of the inlet 48 of the mixing flow path 46b of the second burner 42b (reference Figure 8 ) orthogonal sections.

[0124] (Regarding the diameter of the flow channel 100)

[0125] exist Figures 4 to 6 In the burner assembly 32 shown, the first cross-sectional area S1 of the inlet flow path 110 when viewed along the extension direction of the flow path 100, that is, along the central axis O, is larger than the second cross-sectional area S2 of the mixing flow path 46 when viewed along the central axis O. Specifically, Figures 4 to 6 In the burner assembly 32 shown, in the region upstream of the position where the protrusion 51 appears in the inlet flow path 110 in the air flow direction, the inner diameter Du of the inlet flow path 110 is larger than the inner diameter Dm of the mixing flow path 46a. Figure 13 As shown, the inner diameter of the introduction flow path 110 in the peripheral wall portion 116 is equal to the inner diameter Du of the introduction flow path 110 in a region upstream of the position where the protrusion 51 appears in the introduction flow path 110 in the air flow direction.

[0126] exist Figure 11 and Figure 12 In the burner assembly 32 shown, the first cross-sectional area S1 of the inlet flow path 110 when viewed along the central axis O is larger than the second cross-sectional area S2 of the mixing flow path 46 when viewed along the central axis O. Specifically, Figure 11 and Figure 12In the illustrated burner assembly 32, the equivalent diameter Due of the inlet flow passage 110 is greater than the inner diameter Dm of the mixing flow passage 46a in a region upstream of the position where the protrusion 51 appears in the inlet flow passage 110 in the air flow direction. The equivalent diameter Due of the inlet flow passage 110 is the diameter of a circle having a cross-sectional area equal to the cross-sectional area of ​​the inlet flow passage 110 when viewed along the central axis O. In the following description, the equivalent diameter in a certain cross section is assumed to be the diameter of a circle having a cross-sectional area equal to the cross-sectional area of ​​the cross section.

[0127] exist Figures 4 to 6 、 Figure 11 and Figure 12 In the burner assembly 32 shown, the diameter Dic (refer to Figure 5 、 Figure 13 ), that is, in Figures 4 to 6 、 Figure 11 and Figure 12 The distance between the two base end portions 431 facing each other across the central axis O in the burner assembly 32 shown is as follows: Figure 13 、 Figure 14 and the following Figure 25 As shown, the inner diameter Dm of the mixing flow path 46a may be greater than or equal to the inner diameter Dm of the mixing flow path 46a.

[0128] For example, as described below Figure 25 As shown, the protrusion 50 can be attached to the flow path wall 55 by inserting the protrusion 50, which is formed of a member different from the member constituting the flow path wall 55, into a fuel chamber (Fuel Plenum) 55PL, which is a space formed within the flow path wall 55 and capable of storing fuel, and then fixing it to the flow path wall 55. In this case, the diameter Dic of the inscribed circle can be larger than the inner diameter Dm of the mixing flow path 46a, or can be made equal to the inner diameter Dm of the mixing flow path 46a by increasing the diameter of the protrusion 50 on the upstream side of the portion inserted into the flow path wall 55.

[0129] In addition, in Figures 4 to 6 、 Figure 11 and Figure 12 When the protrusion 50 and the flow path wall 55 are formed as one body as in the exemplary embodiment shown in FIG. Figure 5 and Figure 13 As shown, the diameter Dic of the inscribed circle may be equal to or greater than the inner diameter Dm of the mixing flow path 46a.

[0130] exist Figures 4 to 6 、 Figure 11 and Figure 12In the burner assembly 32 shown, the upstream end 61 of the partition wall portion 58 partitioning adjacent mixing flow paths 46 is located downstream in the air flow direction from the peripheral wall portion 116 located between two circumferentially adjacent protrusions 51 .

[0131] (Regarding the Operation and Effect of the Burner Assembly 32)

[0132] In the burner assembly 32 thus constructed, compressed air flowing from the engine room 40 into the air flow path 36 passes through the axial gap 23 between the burner assembly 32 and the bottom surface 21 of the casing 20 and flows into each of the inlet flow paths 110 provided in each of the plurality of burners 42 of the burner assembly 32 .

[0133] The compressed air flowing into each inlet flow path 110 is discharged from the upstream end portion of the inlet flow path 110 (the upstream end portion of the flow path 100), that is, the upstream end portion 111 (refer to Figure 4 ) is rectified while flowing toward the downstream side of the air flow direction.

[0134] Since the second cross-sectional area S2 of the mixing flow path 46 is smaller than the first cross-sectional area S1 of the inlet flow path 110, the air flowing in the radially outer area within the inlet flow path 110 flows toward the downstream side while flowing into the mixing flow path 46 along the upstream end 61 of the partition wall portion 58 toward the radial inner side.

[0135] Fuel is injected into the flow path 100 from the fuel injection holes 53 formed in the side surface 44 of the protrusion 50 that protrudes radially inward.

[0136] like Figure 6 and Figure 12 As shown, air flowing along the upstream end 61 of the partition wall 58 flows into the mixing flow path 46 so as to enter between the fuel injected from the fuel injection holes 53 and the wall surface 55s of the flow path wall 55 of the mixing flow path 46. Therefore, it is difficult for a region with a high fuel concentration to form near the wall surface 55s of the flow path wall 55. As a result, the risk of flashback, or backfire, from the outlet 47 of the mixing flow path 46 can be suppressed.

[0137] Furthermore, in the burner assembly 32 thus configured, the fuel injection holes 53 are formed in the inlet passage 110 at a position closer to the inlet 48 than the upstream end 111. Consequently, even if air with disrupted flow flows into the inlet passage 110, it is straightened as it reaches the vicinity of the fuel injection holes 53 (near the fuel jet). This minimizes the effects of disrupted air flow before entering the inlet passage 110, making it less likely that a region with low flow velocity and high fuel concentration will form near the fuel injection holes 53 (near the fuel jet). Consequently, the risk of flashback can be reduced.

[0138] Since the burner 4 according to one embodiment includes the burner assembly 32 , the risk of flashback can be suppressed, and thus the burner 4 can be used stably.

[0139] Since the gas turbine 1 according to one embodiment includes the combustor 4 described above, the risk of flashback can be suppressed and the gas turbine can be operated stably.

[0140] Figure 15 These are diagrams for explaining the dimensions of each part of the burner assembly 32 according to several embodiments. Figure 16 These are diagrams for explaining the dimensions of each part of the burner assembly 32 according to several embodiments. Figure 17 It is a diagram for explaining changes in the shape of the protrusion 50 . Figure 18 It is viewed from the upstream side of the air flow direction. Figure 17 A cross-sectional view of part XVIII surrounded by a dotted line. Figure 19 It is observed from the upstream side of the air flow direction. Figure 17 The figure corresponding to the cross-sectional view of the portion XVIII surrounded by the dotted line shows another example. Figure 20 It is a diagram for explaining changes in the shape of the protrusion 50 . Figure 21 It is viewed from the upstream side of the air flow direction. Figure 20 A cross-sectional view of the XXI portion surrounded by a dotted line.

[0141] Figure 22 These are diagrams for explaining modified examples of the introduction flow path wall 115 and the flow path wall 55 . Figure 23 This is a schematic diagram for explaining the extending direction of the fuel injection hole 53 , and shows a cross section perpendicular to the central axis O. Figure 24 This is a schematic diagram for explaining the extending direction of the fuel injection hole 53 , and shows a cross section perpendicular to the central axis O. Figure 25 This is a diagram showing another example of the protrusion 50 of the fuel nozzle 43. Figure 5 The sectional view taken along the XXV-XXV arrow is equivalent to FIG.

[0142] (Dimensions of Each Part of the Burner Assembly 32)

[0143] In the burner assembly 32 involved in several embodiments, as shown in FIG. Figure 15 As shown, the first distance L1 in the extension direction of the central axis O between the upstream end 111 of the flow path 100 and the center position of the opening 53ap in the protrusion 51 of the fuel injection hole 53 is more than 1 times the inner diameter Dm of the mixing flow path 46 when observed from the extension direction of the central axis O, and can preferably be more than 5 times.

[0144] As a result, the air can be effectively rectified in the introduction flow path 110 , and thus the risk of flashback can be effectively suppressed.

[0145] In addition, when the cross-sectional shape of the mixing flow path 46 when viewed in the extending direction of the central axis O is a shape other than a circle, the above-mentioned inner diameter Dm is set to the equivalent diameter of the mixing flow path 46 .

[0146] In the burner assembly 32 involved in some embodiments, the second distance L2 in the extension direction between the inlet 48 of the mixing flow path 46 and the upstream end 44u of the side surface 44 of the protrusion 50 can be less than 1 times the inner diameter Dm of the mixing flow path 46 when viewed in the extension direction of the center axis O.

[0147] This can suppress the length of the protrusion 51 along the extending direction of the central axis O from increasing, thereby suppressing the generation of a low-speed region near the wall surface of the flow path 100 .

[0148] In addition, when the cross-sectional shape of the mixing flow path 46 when viewed in the extending direction of the central axis O is a shape other than a circle, the above-mentioned inner diameter Dm is set to the equivalent diameter of the mixing flow path 46 .

[0149] In the burner assembly 32 involved in several embodiments, the third distance L3 in the extension direction of the central axis O between the inlet 48 of the mixing flow path 46 and the center position of the opening 53ap in the protrusion 51 of the fuel injection hole 53 can be greater than the opening diameter dap of the opening 53ap and less than the second distance L2.

[0150] As described above, when air flows from inlet passage 110 into mixing passage 46, the cross-sectional area of ​​passage 100, as viewed in the direction in which passage 100 extends, decreases. Consequently, the air flowing from inlet passage 110 into mixing passage 46 generates a radially inward flow near inlet 48 of mixing passage 46. This makes it less likely that the fuel ejected from fuel injection holes 53 will form a high-fuel-concentration region near wall surface 55s of mixing passage 46. Consequently, the risk of flashback can be suppressed.

[0151] However, if the third distance L3 is less than the opening diameter dap of the opening 53ap, the fuel injection hole 53 is too close to the mixing flow path 46, so it is difficult for air to enter between the fuel injected from the fuel injection hole 53 and the wall surface 55s of the flow path wall 55 of the mixing flow path 46, thereby possibly weakening the effect of the present invention that it is difficult to form a region with a high fuel concentration near the wall surface 55s of the mixing flow path 46.

[0152] Furthermore, if the third distance L3 is greater than the second distance L2, the fuel injection hole 53 separates excessively toward the upstream side from the vicinity of the inlet 48 of the mixing flow path 46 that generates the air flow toward the radial inside, so that a region with a high fuel concentration may be easily formed near the inner wall of the inlet flow path 110.

[0153] According to the burner assembly 32 according to some embodiments, the fuel injected from the fuel injection holes 53 is less likely to form a high-fuel-concentration region near the inner wall of the introduction flow path 110 or the mixing flow path 46 , thereby suppressing the risk of flashback.

[0154] In the burner assembly 32 according to some embodiments, the upstream end portion 111 of the introduction flow path 110 and the upstream end portion 51t of the protrusion 51 (see Figure 15 ) in the extension direction of the center axis O between the two sides may be greater than 0.

[0155] This ensures the rectifying effect of the air introduced into the flow path 110 and suppresses the risk of flashback.

[0156] like Figure 16 As shown, in the burner assembly 32 involved in several embodiments, when the upstream end 51t of the protrusion 51 is located downstream of the upstream end 111 of the inlet flow path 110, the inner diameter Du of at least a portion of the inlet flow path 110 that is upstream of the end 432t when viewed from the extension direction of the central axis O can be equal to the following value, which is a value obtained by subtracting twice the thickness t1 of the partition wall 118 (118ab) separating the inlet flow path 110 (110a) in the first flow path 100a from the central axis O of the inlet flow path 110 (110b) in the second flow path 100b from the separation distance P between the central axis O of the inlet flow path 110 (110a) in the first flow path 100a and the central axis O of the inlet flow path 110 (110b) in the second flow path 100b (Du=P-2×t1).

[0157] Thus, the inner diameter Du of the introduction flow path 110 can be adjusted by appropriately adjusting the thickness t1 of the partition wall 118 ( 118 ab ) separating the introduction flow path 110 ( 110 a ) in the first flow path 100 a from the introduction flow path 110 ( 110 b ) in the second flow path 100 b .

[0158] In the burner assembly 32 according to some embodiments, for example, Figure 7 As shown, the top surface 54 of the front end portion 432 may have an arc shape in a cross section along the extending direction of the central axis O. That is, in the burner assembly 32 according to some embodiments, the convex curved surface 56 may be a spherical surface.

[0159] Thus, the distance from the upstream end 111 of the inlet flow path 110 to the base end 431 can be suppressed, and the flow of air from the front end 432 to the base end 431 can be less disrupted, thereby easily ensuring the effect of the present invention that it is difficult to form an area with high fuel concentration near the wall 55s of the mixing flow path 46.

[0160] In the burner assembly 32 according to some embodiments, the convex surface 56 may be a conical surface or a pyramidal surface instead of a spherical surface. Furthermore, when the convex surface 56 is a conical surface or a pyramidal surface, the surface shape can be smoothly changed from the base end 431 to the conical surface or the pyramidal surface.

[0161] Furthermore, in the burner assembly 32 according to some embodiments, the convex surface 56 may be, for example, an ogive shape like a cone at the tip of a rocket, or a rotation surface of a quadratic curve such as a parabola.

[0162] In the burner assembly 32 according to some embodiments, for example, Figure 17 As shown, the top surface 54 of the front end portion 432 may have an elliptical arc shape in a cross section along the extending direction of the central axis O.

[0163] Thus, for example, Figure 17 As shown, if the major axis of the elliptical arc is along the extension direction of the central axis O, then Figure 7 Compared with the case where the top surface 54 of the front end portion 432 has an arc shape in the cross section along the extension direction as shown, the flow of air from the front end portion 432 to the base end portion 431 can be made more difficult to be disrupted, thereby making it easier to ensure the effect of the present invention that it is difficult to form an area with a high fuel concentration near the wall surface 55s of the mixing flow path 46.

[0164] And, for example, if the minor axis of the elliptical arc is along the extension direction of the central axis O, then Figure 7 Compared with the case where the top surface 54 of the front end portion 432 has an arc shape in the cross section along the extension direction as shown, the distance from the upstream end portion 111 of the inlet flow path 110 to the base end portion 431 can be suppressed, thereby suppressing the total length of the flow path 100 from becoming longer.

[0165] In addition, the shape of the protrusion 51 of the front end portion 432 that protrudes into the inlet flow path 110 may be, for example, as follows: Figure 18 As shown in FIG, the cross section observed in a plane perpendicular to the central axis O is a circular shape, for example, it can also be as shown in FIG. Figure 19 As shown, the cross section viewed in a plane perpendicular to the central axis O has an elliptical shape.

[0166] exist Figure 19In the illustrated example, the vertex located on the major axis of the ellipse protrudes into the inlet flow path 110 , but the vertex located on the minor axis of the ellipse does not necessarily have to protrude into the inlet flow path 110 .

[0167] In the burner assembly 32 according to some embodiments, the protrusion 51 may be as follows: Figure 20 and Figure 21 As shown, the base end portion 431 is on a plane perpendicular to the central axis O ( Figure 21 ) in a cross-section observed in the figure, and having a shape other than a circle or an ellipse, for example, a rectangular shape with rounded corners.

[0168] In the burner assembly 32 according to some embodiments, the protrusion 50 may be, for example, Figure 20 、 Figure 21 and Figures 23 to 25 The hollow shape shown has a space 50a inside which can store fuel.

[0169] In addition, although Figure 9 、 Figure 10 Omitted, but if Figure 25 As shown, a fuel chamber 55PL capable of storing fuel, which is a space communicating with the space 50 a , may be formed in the flow path wall 55 on the downstream side of the protrusion 50 in the air flow direction.

[0170] (Regarding Modifications of the Introducing Flow Path Wall 115 and the Flow Path Wall 55)

[0171] like Figure 22 As shown, a gap can be provided between the inlet flow path wall 115 forming the inlet flow path 110 (110a) of the first burner 42a and the inlet flow path wall 115 forming the inlet flow path 110 (110b) of the second burner 42b, and the gap can be used as a flow path 119 for compressed air. Then, an opening 55ap connected to the wall surface 55s of the flow path wall 55 forming the mixing flow path 46 and the flow path 55fp of the above-mentioned flow path 119 can be provided so that the compressed air from the flow path 119 is ejected from the opening 55ap, so that the wall surface 55s of the flow path wall 55 can be film-cooled. In addition, the position of the opening 55ap in the direction of the center axis O can be adjusted at the outlet 47 (refer to Figure 4 )nearby.

[0172] (Regarding the Extending Direction of the Fuel Injection Hole 53)

[0173] For example, Figure 23 As shown, the fuel injection holes 53 may each extend in a direction orthogonal to the central axis O to inject fuel toward the central axis O of the flow path 100 .

[0174] And, for example, Figure 24 As shown, each of the fuel injection holes 53 may extend in a direction inclined with respect to the direction orthogonal to the center axis O.

[0175] In addition, Figure 23 and Figure 24 In the example shown, the fuel injection holes 53 may each extend along a plane orthogonal to the central axis O, as shown in FIG. Figure 25 As shown, it may be inclined toward the downstream side in the air flow direction.

[0176] (Regarding Another Embodiment of the First Region 101)

[0177] For example, Figure 4 As shown, in the burner assembly 32 involved in the above-mentioned several embodiments, at the upstream end of the inlet flow path 110 (the upstream end of the flow path 100), that is, the upstream end 111, the inlet flow path wall 115 forming the inlet flow path 110 has a flat surface extending in a direction perpendicular to the central axis O of the flow path 100.

[0178] If such a flat surface exists, air flowing from the outside along the extending direction of the central axis O will collide with the flat surface and be disrupted, thereby creating a risk of separating from the inner peripheral surface near the inlet of the inlet flow path 110 and flowing. Furthermore, even if such air flow is slightly disrupted, in the burner assembly 32 according to the several embodiments described above, the air is rectified while flowing through the inlet flow path 110, thereby reducing the risk of flashback.

[0179] In the burner assembly 32 according to another embodiment described below, in order to smooth the flow of air when it flows into the introduction flow path 110 , an inlet region 112 configured as described below is provided in the introduction flow path 110 .

[0180] Figure 26 This is a schematic diagram of a portion of the burner assembly 32 according to a modified example of the first region 101 as viewed along the central axis L from the upstream side in the air flow direction.

[0181] Figure 27 is a schematic cross-sectional view showing the first region 101 (introduction channel 110) viewed in a cross section including the central axis O of the channel 100, showing Figure 26 AA section or BB section.

[0182] Figure 28 is a schematic cross-sectional view showing the first region 101 (introduction channel 110) viewed in a cross section including the central axis O of the channel 100, showing Figure 26 AA section or BB section.

[0183] Figure 29 is a schematic cross-sectional view showing the first region 101 (introduction channel 110) viewed in a cross section including the central axis O of the channel 100, showing Figure 26 AA section or BB section.

[0184] In addition, Figure 27 、 Figure 28 and Figure 29 In the embodiment, the size of the curvature radius R described later is different.

[0185] In the burner assembly 32 according to another embodiment, a plurality of inlet flow paths 110 are arranged at equal intervals, for example, along a first direction Dr1 perpendicular to the extending direction of the flow path 100 (the extending direction of the central axis O) and a second direction Dr2 perpendicular to the extending direction of the central axis O and the first direction Dr1.

[0186] like Figure 26 As shown, in the burner assembly 32 according to another embodiment, the introduction flow path 110 is provided so that inner peripheral surfaces (inner wall surfaces 115Is) of introduction regions 113 described later, which are adjacent in the first direction Dr1, are separated by a distance La.

[0187] For convenience of explanation, in the burner assembly 32 according to another embodiment, the introduction flow path 110 is provided so that the inner wall surfaces 115Is of the introduction regions 113 adjacent to each other in the second direction Dr2 are separated from each other by a distance La or more.

[0188] In the burner assembly 32 according to another embodiment, a direction extending in a direction different from the first direction and the second direction and perpendicular to the extending direction of the central axis O is referred to as a third direction Dr3.

[0189] In the burner assembly 32 according to another embodiment, the introduction flow path 110 is provided so that the inner wall surfaces 115Is of the introduction regions 113 adjacent to each other in the third direction Dr3 are separated by a distance Lb.

[0190] In this case, since the inner wall surfaces 115Is of the adjacent introduction regions 113 in the second direction Dr2 are separated by a distance La or more, the angular difference between the first direction Dr1 and the third direction Dr3 is 45 degrees or more and less than 90 degrees.

[0191] The introduction flow path 110 according to another embodiment includes an inlet region 112 including an upstream end portion 111 and an introduction region 113 connected to the inlet region 112 on the downstream side of the inlet region 112 .

[0192] For example, Figures 27 to 29Or as shown in the figures described later, the inlet area 112 is formed by an inner wall surface 112Is that is formed as a curved line convex toward the inner side of the first area 101 in the cross section along the extension direction of the flow path 100 (the extension direction of the central axis O), and the cross-sectional area of ​​the flow path 100 gradually decreases as it moves toward the downstream side.

[0193] In the inlet flow path 110 involved in another embodiment, the position of the center (center of curvature) Ca of the curvature radius R of the inner wall surface 112Is of the inlet area 112 is set so that the inner wall surface 112Is convexes toward the inside of the first area 101 in a cross section along the extension direction of the central axis O, for example.

[0194] The introduction region 113 is defined by an inner wall surface 115Is of the introduction flow path wall 115, which is formed as a straight line parallel to the extension direction of the central axis O in a cross section along the extension direction of the central axis O (axis O direction). In other words, the inner peripheral surface of the introduction region 113 constitutes the inner wall surface 115Is of the introduction flow path wall 115.

[0195] The introduction region 113 has the same structure as the introduction flow path 110 of the above-mentioned several embodiments. As in the above-mentioned several embodiments, the downstream side of the introduction region 113 is connected to the mixing flow path 46 by the inlet 48 of the mixing flow path 46 (for example, refer to Figure 6 、 Figure 12 In other words, the introduction flow path 110 according to another embodiment is formed by adding an inlet region 112 to the upstream side of the introduction flow path 110 of the aforementioned embodiments.

[0196] In another embodiment, the entrance area 112 and the introduction area 113 are connected at a connection point 114. At the connection point 114, the inner wall surface 112Is defining the entrance area 112 and the inner wall surface 115Is defining the introduction area 113 are smoothly connected without any steps along the entire circumference of the connection point 114.

[0197] That is, in the inlet flow path 110 involved in another embodiment, in the cross section along the extension direction of the central axis O (axis O direction), the position in the axis O direction of the center of curvature Ca of the inner wall surface 112Is of at least the inner wall surface 112Is near the connection position 114 that defines the inlet area 112 is set to be consistent with the position in the axis O direction of the connection position 114.

[0198] By setting the position of the center of curvature Ca in the direction of the axis O in this manner, the tangent direction of the inner wall surface 1121s at the connection position 114 coincides with the direction of the axis O in a cross section along the extension direction of the central axis O (the direction of the axis O). As a result, the inner wall surface 1121s defining the entrance region 112 and the inner wall surface 1151s defining the introduction region 113 can be smoothly connected throughout the entire circumference of the connection position 114.

[0199] (Regarding the size of the curvature radius R and the shape of the inner wall surface 112Is)

[0200] For example, Figure 27 Show Figure 27 The curvature radius R in the cross section shown is 0.5 times (R=0.5×L) the distance L (eg, distance La, distance Lb) between the inner wall surfaces 115Is of the adjacent introduction regions 113 in the cross section.

[0201] In this case, the inner wall surface 112Is defining the inlet region 112 has a semicircular arc shape and is smoothly connected to the inner wall surfaces 115Is of the two adjacent introduction regions 113 in the cross section at the connection position 114 .

[0202] For example, Figure 28 Show Figure 28 The curvature radius R in the cross section shown is smaller than 0.5 times the distance L between the inner wall surfaces 115Is of the adjacent introduction regions 113 in the cross section (R<0.5×L).

[0203] In this case, of the inner wall surfaces 115Is of the two adjacent introduction areas 113 in the cross section, for example, the inner wall surface 115Is of the introduction area 113 on the left side in the figure, the inner wall surface 112Is of the entrance area 112 connected thereto from the inner wall surface 115Is is smoothly connected at the connection position 114. Furthermore, of the inner wall surfaces 115Is of the two adjacent introduction areas 113 in the cross section, for example, the inner wall surface 115Is of the introduction area 113 on the right side in the figure, the inner wall surface 112Is of the entrance area 112 connected thereto from the inner wall surface 115Is is smoothly connected at the connection position 114.

[0204] In this case, the inner wall surface 112Is of the inlet area 112 on the left side of the figure cannot be connected to the inner wall surface 112Is of the inlet area 112 on the right side of the figure while maintaining their curvature radius, or even if they can be connected, the connection portion will have a shape that is concave toward the downstream side.

[0205] Therefore, when the radius of curvature R is less than 0.5 times the distance L (R < 0.5 × L), the upstream end portion 111 is formed by the flat surface 112p, and the inner wall surface 112Is of the inlet region 112 on the left side of the figure and the inner wall surface 112Is of the inlet region 112 on the right side of the figure are smoothly connected to the flat surface 112p. In this case, the distance between the flat surface 112p and the connection point 114 in the direction of the axis O is equal to the radius of curvature R.

[0206] For example, Figure 29 Show Figure 29 The curvature radius R in the cross section shown exceeds 0.5 times the distance L between the inner wall surfaces 115Is of the adjacent introduction regions 113 in the cross section (R>0.5×L).

[0207] In this case, of the inner wall surfaces 115Is of the two adjacent introduction areas 113 in the cross section, for example, the inner wall surface 115Is of the introduction area 113 on the left side in the figure, the inner wall surface 112Is of the entrance area 112 connected thereto from the inner wall surface 115Is is smoothly connected at the connection position 114. Furthermore, of the inner wall surfaces 115Is of the two adjacent introduction areas 113 in the cross section, for example, the inner wall surface 115Is of the introduction area 113 on the right side in the figure, the inner wall surface 112Is of the entrance area 112 connected thereto from the inner wall surface 115Is is smoothly connected at the connection position 114.

[0208] Furthermore, the inner wall surface 112Is of the inlet region 112 on the left side in the drawing is connected to the inner wall surface 112Is of the inlet region 112 on the right side in the drawing.

[0209] In this case, the connection portion 112c between the inner wall surface 112Is of the inlet area 112 on the left side of the figure and the inner wall surface 112Is of the inlet area 112 on the right side of the figure is formed. Figure 29 The cross section shown has a pointed shape.

[0210] In addition, Figure 29 In the figure, the dotted arc extending from the connecting portion 112c is an imaginary line when the inner wall surface 112Is of the entrance area 112 on the left side of the figure is extended to the right side of the figure, and the imaginary line when the inner wall surface 112Is of the entrance area 112 on the right side of the figure is extended to the left side of the figure, both of which are arcs with a curvature radius R. Figure 32A 、 Figure 33A and Figure 33B Same.

[0211] Regarding the inlet region 112 configured in this manner, several examples will be described in which the relationship between the distance La and the distance Lb and the curvature radius R is changed. In addition, the distance Lb is larger than the distance La.

[0212] (When R < 0.5 × La)

[0213] A case will be described where the curvature radius R is constant throughout the entire circumference of the entrance region 112 and is smaller than 0.5 times the distance La (R<0.5×La).

[0214] Figure 30A This is for the case where the curvature radius R is less than 0.5 times the distance La (R<0.5×La). Figure 26 Schematic cross-sectional view of section AA in FIG.

[0215] Figure 30B This is for the case where the curvature radius R is less than 0.5 times the distance La (R<0.5×La). Figure 26 Schematic cross-sectional view of section BB in FIG.

[0216] When the curvature radius R is less than 0.5 times the distance La (R<0.5×La), Figure 26 AA section and Figure 26 In any of the BB cross sections, the shape of the inlet region 112 becomes the same as Figure 28 That is, when the curvature radius R is less than 0.5 times the distance La (R<0.5×La), Figure 26 AA section and Figure 26 In any of the BB cross sections, the upstream end portion 111 is formed of a flat surface 112p. That is, when the curvature radius R is less than 0.5 times the distance La (R<0.5×La), the inlet region 112 is surrounded by the flat surface 112p throughout its entire circumference.

[0217] However, when the radius of curvature R is less than 0.5 times the distance La (R < 0.5 × La), inlet region 112 is formed by inner wall surface 112Is, which has a curved line with radius of curvature R in a cross section along axis O, in addition to flat surface 112p. Therefore, when air flows into inlet region 112, it is easily guided into inlet region 112, making it less likely for air to separate from the inner circumferential surfaces (inner wall surface 112Is and inner wall surface 115Is) of inlet region 112 and introduction region 113. This reduces pressure loss in first region 101 (introduction flow path 110) and minimizes flow path deviation in first region 101 (introduction flow path 110). Consequently, the risk of flashback can be further effectively suppressed.

[0218] (When R=0.5×La)

[0219] A case will be described where the curvature radius R is constant throughout the entire circumference of the entrance region 112 and is 0.5 times the distance La (R=0.5×La).

[0220] Figure 31A This is the case where the curvature radius R is 0.5 times the distance La (R=0.5×La). Figure 26 Schematic cross-sectional view of section AA in FIG.

[0221] Figure 31B This is the case where the curvature radius R is 0.5 times the distance La (R=0.5×La). Figure 26 Schematic cross-sectional view of section BB in FIG.

[0222] That is, in the burner assembly 32 involved in another embodiment, in each of the inlet regions 112, the inner peripheral surface (inner wall surface 112Is) of the inlet region 112 observed in the cross section of the inlet region 112 along the axis O direction can be formed into a curved shape having a curvature radius R that is 0.5 times the distance La between the inner peripheral surfaces (inner wall surfaces 115Is) of the adjacent inlet regions 113 in the first direction Dr1.

[0223] When the curvature radius R is 0.5 times the distance La (R=0.5×La), Figure 26 In the AA section, the shape of the inlet region 112 becomes the same as Figure 27 That is, when the curvature radius R is 0.5 times the distance La (R=0.5×La), Figure 26 In the AA section, the inner wall surface 112Is defining the inlet region 112 has a semicircular arc shape and is smoothly connected to the inner wall surfaces 115Is of the two adjacent introduction regions 113 in the above section at the connection position 114.

[0224] When the curvature radius R is 0.5 times the distance La (R=0.5×La), Figure 26 In the BB section, the shape of the inlet region 112 becomes the same as Figure 28 That is, when the curvature radius R is 0.5 times the distance La (R=0.5×La), Figure 26 In the BB cross section in FIG, the upstream end portion 111 is composed of a flat surface 112 p.

[0225] When the curvature radius R is 0.5 times the distance La (R=0.5×La), Figure 26 In the AA section, the shape of the inlet region 112 becomes the same as Figure 27In addition to the flat surface 112p, the inlet region 112 is formed by an inner wall surface 112Is having a curved line with a radius of curvature R in a cross section along the axis O. Therefore, when air flows into the inlet region 112, it is easily guided into the inlet region 112, making it less likely for air to separate from the inner circumferential surfaces (inner wall surface 112Is and inner wall surface 115Is) of the inlet region 112 and the introduction region 113. This reduces pressure loss in the first region 101 (introduction flow path 110) and minimizes flow path deviation in the first region 101 (introduction flow path 110). Consequently, the risk of flashback can be further effectively suppressed.

[0226] (When R=0.5×Lb)

[0227] A case will be described where the curvature radius R is constant throughout the entire circumference of the entrance region 112 and is 0.5 times the distance Lb (R=0.5×Lb).

[0228] Figure 32A This is the case where the curvature radius R is 0.5 times the distance Lb (R=0.5×Lb). Figure 26 Schematic cross-sectional view of section AA in FIG.

[0229] Figure 32B This is the case where the curvature radius R is 0.5 times the distance Lb (R=0.5×Lb). Figure 26 Schematic cross-sectional view of section BB in FIG.

[0230] That is, in the burner assembly 32 involved in another embodiment, in each of the inlet areas 112, the inner peripheral surface (inner wall surface 112Is) of the inlet area 112 observed in the cross section of the inlet area 112 along the axis O direction can be formed into a curved shape having a curvature radius R of 0.5 times the distance Lb between the inner peripheral surfaces (inner wall surfaces 115Is) of the adjacent inlet areas 113 extending in a direction different from the first direction Dr1 and the second direction Dr2 and orthogonal to the axis O direction.

[0231] When the curvature radius R is 0.5 times the distance Lb (R=0.5×Lb), Figure 26 In the AA section, the shape of the inlet region 112 becomes the same as Figure 29 That is, when the curvature radius R is 0.5 times the distance Lb (R=0.5×Lb), Figure 26 In the AA cross section in FIG. 1 , the connection portion 112 c has a pointed shape.

[0232] When the curvature radius R is 0.5 times the distance Lb (R=0.5×Lb), Figure 26In the BB section, the shape of the inlet region 112 becomes the same as Figure 27 That is, when the curvature radius R is 0.5 times the distance Lb (R=0.5×Lb), Figure 26 In the BB cross section in FIG. 1 , the inner wall surface 112Is defining the inlet region 112 has a semicircular arc shape and is smoothly connected to the inner wall surfaces 115Is of the two adjacent introduction regions 113 in the cross section at the connection position 114 .

[0233] When the curvature radius R is 0.5 times the distance Lb (R=0.5×Lb), Figure 26 In the BB section, the shape of the inlet region 112 becomes the same as Figure 27 The same shape as shown does not form the flat surface 112p over the entire circumference of the inlet region 112. Therefore, when air flows into the inlet region 112, the air is easily guided into the inlet region 112, and thus the air is less likely to separate from the inner circumferential surfaces (inner wall surface 112Is, inner wall surface 115Is) of the inlet region 112 and the introduction region 113.

[0234] In particular, the distance L between the inner wall surfaces 115Is of two adjacent introduction areas 113 becomes the largest. Figure 26 In the BB section, the shape of the inlet region 112 becomes the same as Figure 27 Because the shape is the same as that shown, when air flows into inlet region 112, it is more easily guided into inlet region 112. This reduces pressure loss in first region 101 (introduction flow path 110) and minimizes flow path deviation in first region 101 (introduction flow path 110). Consequently, the risk of flashback can be further effectively suppressed.

[0235] (When R>0.5×Lb)

[0236] A case will be described where the curvature radius R is constant throughout the entire circumference of the entrance region 112 and exceeds 0.5 times the distance Lb (R>0.5×Lb).

[0237] Figure 33A This is for the case where the curvature radius R exceeds 0.5 times the distance Lb (R>0.5×Lb). Figure 26 Schematic cross-sectional view of section AA in FIG.

[0238] Figure 33B This is for the case where the curvature radius R exceeds 0.5 times the distance Lb (R>0.5×Lb). Figure 26 Schematic cross-sectional view of section BB in FIG.

[0239] That is, in the burner assembly 32 involved in another embodiment, in each of the inlet areas 112, the inner peripheral surface (inner wall surface 112Is) of the inlet area 112 observed in the cross section of the inlet area 112 along the axis O direction can be formed into a curved shape having a curvature radius R that exceeds 0.5 times the distance Lb between the inner peripheral surfaces (inner wall surfaces 115Is) of the adjacent inlet areas 113 extending in a third direction Dr3 different from the first direction Dr1 and the second direction Dr2 and orthogonal to the axis O direction.

[0240] When the curvature radius R exceeds 0.5 times the distance Lb (R>0.5×Lb), Figure 26 AA section and Figure 26 In any of the BB cross sections, the shape of the inlet region 112 becomes the same as Figure 29 That is, when the curvature radius R exceeds 0.5 times the distance Lb (R>0.5×Lb), Figure 26 AA section and Figure 26 In any of the cross sections along line BB in FIG, connection portion 112c has a pointed shape. Specifically, when the radius of curvature R exceeds 0.5 times the distance Lb (R>0.5×Lb), the entire perimeter of inlet region 112 is surrounded by the pointed connection portion 112c. Therefore, when the radius of curvature R exceeds 0.5 times the distance Lb (R>0.5×Lb), flat surface 112p is not formed.

[0241] When the curvature radius R exceeds 0.5 times the distance Lb (R>0.5×Lb), a flat surface 112p will not be formed throughout the entire circumference of the inlet area 112. Therefore, when air flows into the inlet area 112, the air is easily guided into the inlet area 112, and it is not easy for air to peel off from the inner circumferential surface (inner wall surface 112Is, inner wall surface 115Is) of the inlet area 112 and the inlet area 113.

[0242] (Avoid forming the flat surface 112p and the connecting portion 112c having a pointed shape over the entire circumference of the inlet region 112)

[0243] In order to avoid forming the flat surface 112p and the connecting portion 112c having a pointed shape over the entire circumference of the inlet region 112, that is, to make the shape of the inlet region 112 similar to that of the inlet region 112 over the entire circumference of the inlet region 112, Figure 27 The case where the shapes are the same as those shown will be described.

[0244] Figure 34A This is about avoiding forming the flat surface 112p and the connecting portion 112c having a pointed shape over the entire circumference of the inlet area 112. Figure 26Schematic cross-sectional view of section AA in FIG.

[0245] Figure 35B This is about avoiding forming the flat surface 112p and the connecting portion 112c having a pointed shape over the entire circumference of the inlet area 112. Figure 26 Schematic cross-sectional view of section BB in FIG.

[0246] In order to avoid forming a flat surface 112p and a connecting portion 112c with a pointed shape throughout the entire circumference of the entrance area 112, the curvature radius R can be set in any cross-section containing the center axis O so as to be 0.5 times the distance L between the inner wall surfaces 115Is of the adjacent inlet areas 113 in the cross-section (R=0.5×L), that is, the curvature radius R can be set in such a way that the relationship R=0.5×L holds throughout the entire circumference.

[0247] In addition, when using Figures 30A to 34B In each of the embodiments described, the curvature radius R of the inner wall surface 112Is of the inlet area 112 observed in the cross section including the center axis O is constant from the connection position 114 to the upstream end 111, but the curvature radius R can also be changed from the connection position 114 to the upstream end 111.

[0248] Figure 35A This is a diagram showing a case where the shape of the inner wall surface 112Is of the entrance area 112 observed in a cross section including the central axis O is an ellipse having a major axis parallel to the axis O direction over the entire circumference of the entrance area 112. Figure 26 Schematic cross-sectional view of section AA in FIG.

[0249] Figure 35B This is a diagram showing a case where the shape of the inner wall surface 112Is of the entrance area 112 observed in a cross section including the central axis O is an ellipse having a major axis parallel to the axis O direction over the entire circumference of the entrance area 112. Figure 26 Schematic cross-sectional view of section BB in FIG.

[0250] like Figure 35A and Figure 35B As shown, the shape of the inner wall surface 112Is of the inlet region 112 viewed in a cross section including the central axis O can be, for example, an elliptical shape having a major axis parallel to the axis O direction over the entire circumference of the inlet region 112 .

[0251] In addition, if Figure 35A and Figure 35BAs shown, when the shape of the inner wall surface 112Is of the inlet region 112 observed in the cross section including the central axis O is to be an ellipse having a major axis parallel to the axis O, the major axis radius may be at least three times the distance L.

[0252] In use Figures 26 to 34B In each of the embodiments described above, the first direction Dr1 and the second direction are perpendicular to each other, but they do not necessarily need to be perpendicular to each other.

[0253] The present invention is not limited to the above-described embodiment, and includes modified embodiments of the above-described embodiment or appropriate combinations of these embodiments.

[0254] For example, in the above-mentioned embodiment, each burner 42 is configured to include one inlet flow path 110, one mixing flow path 46 and four fuel nozzles 43 arranged around the one mixing flow path 46, and the fuel is injected from the four surrounding fuel nozzles 43 into the one mixing flow path 46, but each burner 42 can also have only one fuel nozzle 43, as long as it has at least one fuel nozzle 43.

[0255] The contents described in each of the above embodiments can be understood, for example, as follows.

[0256] (1) The burner assembly 32 according to at least one embodiment of the present invention is a burner assembly 32 including a plurality of burners 42 for mixing fuel and air. Each of the plurality of burners 42 includes a flow path 100 through which air can flow. The flow path 100 includes: a first region 101 (introduction flow path 110), which is an upstream region of the air flow and has fuel injection holes (fuel injection holes 53) formed therein; and a second region 102 (mixing flow path 46), which is a region further downstream than the first region 101 (introduction flow path 110) and in which the fuel injected from the injection holes (fuel injection holes 53) is mixed with air. The first region 101 (introduction flow path 110) extends from an upstream end 111 of the flow path 100 to a connection position (inlet 48) with the second region 102 (mixing flow path 46). The first region 101 (introduction channel 110) has an injection hole (fuel injection hole 53) formed at a position closer to the connection point (inlet 48) than the upstream end 111. The first region 101 (introduction channel 110) includes at least one protrusion 51 that projects radially inward of the channel 100 and forms the injection hole (fuel injection hole 53), and at least one peripheral wall portion 116 that is adjacent to the at least one protrusion 51 in the circumferential direction of the channel 100 and is not provided with any protrusion 51. Regarding the cross-sectional area of ​​the channel 100 as viewed in the direction in which the channel 100 extends, the second cross-sectional area S2 in the second region 102 (mixing channel 46) is smaller than the first cross-sectional area S1 in the first region 101 (introduction channel 110).

[0257] According to the configuration (1) above, when air flows from the first region 101 (introduction channel 110) into the second region 102 (mixing channel 46), the cross-sectional area of ​​the channel 100, as viewed in the direction in which the channel 100 extends, decreases. Consequently, the air flowing from the first region 101 (introduction channel 110) into the second region 102 (mixing channel 46) generates a radially inward flow near the connection point (inlet 48). This makes it less likely that a region with a high fuel concentration will form near the inner wall (wall surface 55s) of the second region 102 (mixing channel 46). Consequently, the risk of flashback, or backfire, from the outlet 47 of the second region 102 (mixing channel 46) can be suppressed.

[0258] Furthermore, according to the configuration (1) above, the fuel injection hole (fuel injection hole 53) is formed in the first region 101 (introduction flow path 110) at a position closer to the connection point (inlet 48) than the upstream end 111. Thus, even if air with a disrupted flow flows into the first region 101 (introduction flow path 110), it is straightened in the process of reaching the vicinity of the injection hole (fuel injection hole 53) (near the fuel jet) in the first region 101 (introduction flow path 110). Therefore, the influence of the disrupted flow of air before entering the first region 101 (introduction flow path 110) can be suppressed, making it difficult to form a region with low flow velocity and high fuel concentration near the injection hole (fuel injection hole 53) (near the fuel jet). As a result, the risk of flashback can be suppressed.

[0259] (2) In some embodiments, in the structure of (1) above, the first distance L1 in the extension direction between the upstream end 111 of the flow path 100 and the center position of the opening 53ap in the above-mentioned protrusion 51 of the injection hole (fuel injection hole 53) can be greater than or equal to 1 times the equivalent diameter (inner diameter Dm) of the second region 102 (mixing flow path 46) when viewed in the extension direction.

[0260] According to the configuration of (2) above, the air can be effectively rectified in the first region 101 (introduction flow path 110 ), and thus the risk of flashback can be effectively suppressed.

[0261] (3) In some embodiments, in the configuration of (2) above, the first distance L1 may be 5 times or more the equivalent diameter (inner diameter Dm).

[0262] According to the configuration of (3) above, the air can be rectified more effectively in the first region 101 (introduction flow path 110 ), and thus the risk of flashback can be suppressed more effectively.

[0263] (4) In some embodiments, in any of the structures described in (1) to (3), the protrusion 51 may include: a straight portion (base end portion 431) extending in a straight line along the extension direction in a cross section along the extension direction; and a front end portion 432 formed so that the amount of protrusion toward the radial inside gradually increases as it moves toward the straight portion (base end portion 431) on the upstream side relative to the straight portion (base end portion 431).

[0264] According to the configuration (4) above, the tip portion 432 is formed so that the amount of radial inward projection gradually increases as it moves toward the straight portion (base end 431) from the upstream side relative to the straight portion (base end 431). This prevents airflow from the tip portion 432 from moving toward the straight portion (base end 431) from separating. Consequently, it is less likely that a region with low flow velocity and high fuel concentration will form near the injection hole (fuel injection hole 53) (near the fuel jet). As a result, the risk of flashback can be suppressed.

[0265] (5) In some embodiments, in the structure of (4) above, the second distance L2 in the extension direction between the connection position (inlet 48) and the upstream end 44u in the straight portion (base end 431) can be less than 1 times the equivalent diameter (inner diameter Dm) of the second region 102 (mixing flow path 46) when viewed from the extension direction.

[0266] According to the configuration of (5) above, it is possible to suppress the length of the protrusion 51 in the extending direction from increasing, thereby suppressing the generation of a low-speed region near the wall surface of the flow path 100 .

[0267] (6) In some embodiments, in the structure of (4) or (5) above, the third distance L3 in the extension direction between the connection position (inlet 48) and the center position of the opening 53ap in the protrusion 51 of the injection hole (fuel injection hole 53) can be larger than the opening diameter dap of the opening 53ap and smaller than the second distance L2 in the extension direction between the connection position (inlet 48) and the end 44u on the upstream side of the straight portion (base end portion 431).

[0268] According to the configuration of (6) above, the fuel injected from the injection hole (fuel injection hole 53 ) is less likely to form a region with a high fuel concentration near the inner wall of the first region 101 (introduction flow path 110 ) or the second region 102 (mixing flow path 46 ), thereby suppressing the risk of flashback.

[0269] (7) In some embodiments, in any of the structures (4) to (6) above, the surface (top surface 54 ) of the front end portion 432 may have an arc shape in a cross section along the extending direction.

[0270] According to the structure of (7) above, the distance from the upstream end 111 of the flow path 100 to the straight portion (base end 431) can be suppressed, and the flow of air from the front end 432 to the straight portion (base end 431) can be less likely to be disturbed, thereby easily ensuring the effect of the present invention that it is difficult to form a region with a high fuel concentration near the inner wall (wall surface 55s) of the second region 102 (mixing flow path 46).

[0271] (8) In some embodiments, in any of the structures (4) to (6) above, the surface (top surface 54 ) of the front end portion 432 may have an elliptical arc shape in a cross section along the extending direction.

[0272] According to the structure of (8) above, for example, if the major axis of the elliptical arc is along the extension direction of the flow path 100, then compared with the case where the surface of the front end portion 432 (top surface 54) has an arc shape in the cross section along the extension direction, the flow of air from the front end portion 432 to the straight portion (base end portion 431) can be made less likely to be disrupted, thereby making it easier to ensure the effect of the present invention that it is difficult to form a region with a high fuel concentration near the inner wall (wall surface 55s) of the second region 102 (mixing flow path 46).

[0273] Furthermore, for example, if the minor axis of the elliptical arc is along the extension direction of the flow path 100, compared to the case where the surface (top surface 54) of the front end portion 432 has an arc shape in the cross section along the extension direction, the distance from the upstream end portion 111 of the flow path 100 to the straight portion (base end portion 431) can be suppressed, thereby suppressing the total length of the flow path 100 from being lengthened.

[0274] (9) In some embodiments, in any of the configurations (4) to (8) above, the fourth distance L4 in the extending direction between the upstream end 111 of the flow channel 100 and the upstream end 51 t of the protrusion 51 may be equal to or greater than 0.

[0275] According to the configuration of (9) above, it is possible to ensure the air flow straightening effect in the first region 101 (introduction flow path 110 ) and suppress the risk of flashback.

[0276] (10) In some embodiments, in any of the structures described in (1) to (9), the first region 101 (introduction flow path 110) may include: an inlet region 112 including an upstream end portion 111; and an inlet region 113 connected to the inlet region 112 on the downstream side of the inlet region 112. The inlet region 112 is formed by an inner wall surface (inner wall surface 112Is) that is formed in a curved shape and convex toward the inner side of the first region 101 (introduction flow path 110) in a cross section along the extension direction (axis O direction), and the cross-sectional area of ​​the flow path 100 gradually decreases toward the downstream side. The inlet region 113 may be defined by an inner wall surface (inner wall surface 115Is) that is formed in a straight line and parallel to the extension direction (axis O direction) in a cross section along the extension direction (axis O direction).

[0277] According to the configuration of (10) above, when air flows into inlet region 112, it is easily guided into inlet region 112, making it less likely for air to separate from the inner peripheral surfaces (inner wall surface 112Is and inner wall surface 115Is) of inlet region 112 and inlet region 113. This reduces pressure loss in first region 101 (inlet flow path 110) and minimizes flow path deviation in first region 101 (inlet flow path 110). Consequently, the risk of flashback can be further effectively suppressed.

[0278] (11) In some embodiments, in the structure of (10), a plurality of flow paths 100 may be arranged at equal intervals along a first direction Dr1 perpendicular to the extension direction (axis O direction) and a second direction Dr2 perpendicular to the extension direction (axis O direction) and the first direction Dr1. In each inlet region 112, the inner peripheral surface (inner wall surface 112Is) of the inlet region 112 observed in a cross section of the inlet region 112 along the extension direction (axis O direction) may be formed into a curved shape having a curvature radius R that is 0.5 times the distance La between the inner peripheral surfaces (inner wall surfaces 115Is) of adjacent introduction regions 113 in the first direction Dr1.

[0279] According to the configuration (11) above, when air flows into inlet region 112, it is easily guided into inlet region 112, making it less likely for air to separate from the inner peripheral surfaces (inner wall surface 112Is and inner wall surface 115Is) of inlet region 112 and inlet region 113. This reduces pressure loss in first region 101 (inlet flow path 110) and minimizes flow path deviation in first region 101 (inlet flow path 110). Consequently, the risk of flashback can be further effectively suppressed.

[0280] (12) In some embodiments, in the structure of (10), the flow path 100 may be arranged in a plurality at equal intervals along a first direction Dr1 perpendicular to the extension direction (axis O direction) and a second direction Dr2 perpendicular to the extension direction (axis O direction) and the first direction Dr1. In each inlet region 112, the inner peripheral surface (inner wall surface 112Is) of the inlet region 112 observed in a cross section of the inlet region 112 along the extension direction (axis O direction) may be formed into a curved shape having a curvature radius R of 0.5 times the distance Lb between the inner peripheral surfaces (inner wall surfaces 115Is) of adjacent introduction regions 113 extending in a third direction Dr3 that is different from the first direction Dr1 and the second direction Dr2 and perpendicular to the extension direction (axis O direction).

[0281] According to the configuration (12) above, when air flows into inlet region 112, it is easily guided into inlet region 112, making it less likely for air to separate from the inner peripheral surfaces (inner wall surface 112Is and inner wall surface 115Is) of inlet region 112 and inlet region 113. This reduces pressure loss in first region 101 (inlet flow path 110) and minimizes flow path deviation in first region 101 (inlet flow path 110). Consequently, the risk of flashback can be further effectively suppressed.

[0282] (13) In some embodiments, in the structure of (10), the flow path 100 may be arranged in a plurality at equal intervals along a first direction Dr1 perpendicular to the extension direction (axis O direction) and a second direction Dr2 perpendicular to the extension direction (axis O direction) and the first direction Dr1. In each inlet region 112, the inner peripheral surface (inner wall surface 112Is) of the inlet region 112 observed in a cross section of the inlet region 112 along the extension direction (axis O direction) may be formed into a curved shape having a curvature radius R that exceeds 0.5 times the distance Lb between the inner peripheral surfaces (inner wall surfaces 115Is) of adjacent introduction regions 113 extending in a third direction Dr3 that is different from the first direction Dr1 and the second direction Dr2 and perpendicular to the extension direction (axis O direction).

[0283] According to the configuration of (13) above, when air flows into inlet region 112, it is easily guided into inlet region 112, making it less likely for air to separate from the inner peripheral surfaces (inner wall surface 112Is and inner wall surface 115Is) of inlet region 112 and inlet region 113. This reduces pressure loss in first region 101 (inlet flow path 110) and minimizes flow path deviation in first region 101 (inlet flow path 110). Consequently, the risk of flashback can be further effectively suppressed.

[0284] (14) In some embodiments, in any of the configurations (1) to (9) above, the flow path 100 may include a first flow path 100 a and a second flow path 100 b closest to the first flow path 100 a. The upstream end 51 t of the protrusion 51 may be located further downstream than the upstream end 111 of the flow path 100. The diameter (inner diameter Du) of at least a portion of the first region 101 (introduction flow path 110) that is closer to the upstream side than the upstream end 51t of the protrusion 51 when viewed from the extension direction can be equal to the following value, which is a value obtained by subtracting twice the thickness t1 of the partition wall (partition wall portion 118 (118ab)) separating the first region 101 (introduction flow path 110 (110a)) in the first flow path 100a from the center axis (center axis O) along the extension direction of the first region 101 (introduction flow path 110 (110b)) in the second flow path 100b from the separation distance P between the center axis (center axis O) along the extension direction of the first region 101 (introduction flow path 110 (110b)) in the second flow path 100b (Du=P-2×t1).

[0285] According to the structure of (14) above, the inner diameter Du of the inlet flow path 110 can be adjusted by appropriately adjusting the thickness t1 of the partition wall (partition wall portion 118 (118ab)) separating the inlet flow path 110 (110a) in the first flow path 100a from the inlet flow path 110 (110b) in the second flow path 100b.

[0286] (15) A gas turbine combustor (combustor 4) according to at least one embodiment of the present invention comprises: a burner assembly 32 having any one of the structures (1) to (14) above; and a combustion tube 25 forming a space for forming flames on the downstream side of the burner assembly 32.

[0287] According to the configuration of (15), since the burner assembly 32 having any one of the configurations of (1) to (14) is provided, the risk of flashback can be suppressed. Therefore, the gas turbine combustor (combustor 4) can be used stably.

[0288] (16) A gas turbine 1 according to at least one embodiment of the present invention includes: a compressor 2; a gas turbine combustor (combustor 4) configured to be supplied with air and fuel compressed by the compressor 2 and to combust the fuel to generate combustion gas; and a turbine 6 driven by the combustion gas generated in the gas turbine combustor (combustor 4). The gas turbine combustor (combustor 4) is the gas turbine combustor (combustor 4) having the structure described in (15) above.

[0289] According to the configuration of (16), since the gas turbine combustor (combustor 4) having the configuration of (15) is provided, the risk of flashback can be suppressed and the gas turbine 1 can be stably operated.

[0290] Explanation of symbols

[0291] 1-gas turbine, 2-compressor, 4-combustor (gas turbine combustor), 6-turbine, 25-combustion tube, 32-burner assembly, 42-burner, 42a-first burner, 42b-second burner, 43-fuel nozzle, 44-side, 44u-end, 46-mixing flow path, 47-outlet, 48-inlet, 50-protrusion, 51-protrusion, 51t-end, 53-fuel injection hole, 53ap-opening, 5 4-top surface, 55-flow path wall, 55s-wall surface, 58-partition wall portion, 61-end portion, 100-flow path, 100a-first flow path, 100b-second flow path, 101-first region, 102-second region, 110-introduction flow path, 111-upstream end portion, 112-inlet region, 113-introduction region, 115-introduction flow path wall, 116-peripheral wall portion, 118-partition wall portion, 431-base end portion, 432-front end portion.

Claims

1. A burner assembly comprising a plurality of burners for mixing fuel and air, wherein: Each of the plurality of burners includes a flow path through which the air can flow. The flow path includes: a first region which is a region on the upstream side of the flow of the air and in which the injection hole of the fuel is formed; and The second region is a region on the downstream side of the first region and is where the fuel injected from the injection hole mixes with the air. Regarding the first area, extending from the upstream end of the flow path to a connection position with the second region, The injection hole is formed at a position closer to the connection position than the upstream end portion. have: at least one protrusion protruding radially inward of the flow path and having the injection hole formed therein; and at least one peripheral wall portion is adjacent to the at least one protrusion in the circumferential direction of the flow path and is not provided with the protrusion; Regarding the cross-sectional area of ​​the flow path when viewed in the extending direction of the flow path, the second cross-sectional area in the second region is smaller than the first cross-sectional area in the first region.

2. The burner assembly according to claim 1, wherein: A first distance in the extending direction between an upstream end portion of the flow path and a center position of an opening in the protrusion of the injection hole is equal to or greater than one time an equivalent diameter of the second region when viewed in the extending direction.

3. The burner assembly according to claim 2, wherein: The first distance is greater than or equal to 5 times the equivalent diameter.

4. The burner assembly according to claim 1 or 2, wherein: The protrusion comprises: a straight portion extending in a straight line along the extending direction in a cross section along the extending direction; and The front end portion is formed such that the amount of protrusion toward the radial direction inner side gradually increases toward the straight portion on the upstream side of the straight portion.

5. The burner assembly according to claim 4, wherein: A second distance in the extending direction between the connection position and the upstream end portion of the straight portion is equal to or less than 1 times an equivalent diameter of the second region when viewed in the extending direction.

6. The burner assembly according to claim 4, wherein: A third distance in the extending direction between the connecting position and the center position of the opening in the protruding portion of the injection hole is larger than an opening diameter of the opening and smaller than a second distance in the extending direction between the connecting position and the upstream end portion of the straight portion.

7. The burner assembly according to claim 4, wherein: A surface of the front end portion has an arc shape in a cross section along the extending direction.

8. The burner assembly according to claim 4, wherein: A surface of the front end portion has an elliptical arc shape in a cross section along the extending direction.

9. The burner assembly according to claim 4, wherein: A fourth distance in the extending direction between the upstream end portion of the flow path and the upstream end portion of the protrusion is equal to or greater than 0.

10. The burner assembly according to claim 1 or 2, wherein: The first area includes: an inlet region including the upstream end; and an introduction area connected to the inlet area on the downstream side of the inlet area, The inlet region is defined by an inner wall surface that is formed into a curved shape convex toward the inner side of the first region in a cross section along the extending direction, and the cross-sectional area of ​​the flow path gradually decreases toward the downstream side. The introduction region is defined by an inner wall surface formed in a straight line parallel to the extending direction in a cross section along the extending direction.

11. The burner assembly according to claim 10, wherein: A plurality of the flow paths are arranged at equal intervals along a first direction perpendicular to the extending direction and a second direction perpendicular to the extending direction and the first direction. In each of the inlet regions, the inner circumferential surface of the inlet region observed in a cross section of the inlet region along the extending direction is formed into a curved shape having a curvature radius of 0.5 times the distance between the inner circumferential surfaces of the adjacent introduction regions in the first direction.

12. The burner assembly according to claim 10, wherein: A plurality of the flow paths are arranged at equal intervals along a first direction perpendicular to the extending direction and a second direction perpendicular to the extending direction and the first direction. In each of the inlet areas, the inner peripheral surface of the inlet area observed in the cross-section of the inlet area along the extension direction is formed into a curved shape, and the curved shape has a curvature radius of 0.5 times the distance between the inner peripheral surfaces of the adjacent inlet areas extending in a direction different from the first direction and the second direction and orthogonal to the extension direction.

13. The burner assembly according to claim 10, wherein: A plurality of the flow paths are arranged at equal intervals along a first direction perpendicular to the extending direction and a second direction perpendicular to the extending direction and the first direction. In each of the inlet areas, the inner peripheral surface of the inlet area observed in the cross-section of the inlet area along the extension direction is formed into a curved shape, and the curved shape has a curvature radius that exceeds 0.5 times the distance between the inner peripheral surfaces of the adjacent inlet areas extending in a third direction different from the first direction and the second direction and orthogonal to the extension direction.

14. The burner assembly according to claim 1 or 2, wherein: The flow path includes a first flow path and a second flow path closest to the first flow path, The upstream end of the protrusion is located downstream of the upstream end of the flow path. The diameter of at least a portion of the area in the first region that is closer to the upstream side than the upstream end of the protrusion when observed from the extension direction is equal to the following value, which is the value obtained by subtracting twice the thickness of the partition wall separating the first region in the first flow path from the separation distance between the central axis of the first region in the first flow path along the extension direction and the central axis of the first region in the second flow path along the extension direction.

15. A gas turbine combustor comprising: The burner assembly according to claim 1 or 2; and The combustion tube forms a space for forming flames on the downstream side of the burner assembly.

16. A gas turbine comprising: compressor; a gas turbine combustor configured to be supplied with air compressed by the compressor and fuel, and to combust the fuel to generate combustion gas; and a turbine driven by said combustion gases produced in said gas turbine combustor, The gas turbine combustor is the gas turbine combustor according to claim 15.

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