Fuel injector, combustor provided with the fuel injector, and gas turbine provided with the combustor

Abstract

A fuel injector has a body portion extending in an axial direction, the body portion including an axial flow path formed to extend in the axial direction, a radial flow path formed to communicate with the axial flow path at one end and open at an outer surface of the body portion at the other end, and an internal flow path including a first opening portion and a second opening portion that open at the outer surface and formed to extend from the first opening portion to the second opening portion in an inside of the body portion, the first opening portion and the second opening portion being located at opposite sides with respect to a third opening portion of the radial flow path that opens at the outer surface, in a circumferential direction centered on an axis of the body portion.

Description

Technical Field

[0001] This disclosure relates to a fuel injector, a combustor having the fuel injector, and a gas turbine having the combustor.

[0002] This application claims priority based on Japan Patent Application No. 2020-110413 filed with the Japan Patent Office on June 26, 2020, the contents of which are incorporated herein by reference. Background Technology

[0003] In the gas turbine described in Patent Document 1, a fuel injector (peg) with a double-tube structure consisting of an inner tube for fuel flow and an outer tube for air flow is provided. This fuel injector extends in a direction intersecting with the airflow direction, thus sometimes creating stagnant flow in the downstream region of the fuel injector in the direction of airflow. If air containing fuel injected from the fuel injector becomes trapped in such stagnant flow, the reliability of the burner decreases.

[0004] In response to this, in the fuel injector of the gas turbine in Patent Document 1, the outer pipe for air flow is opened at a position corresponding to the area where such stagnation occurs, and air is injected from the opening, thereby pushing the stagnant air and fuel, thus suppressing the formation of stagnation.

[0005] Prior art literature

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2017-180267 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] However, in the gas turbine of Patent Document 1, it is necessary to allow a portion of the air compressed by the compressor to circulate in the outer pipe of the fuel injector. For this purpose, pipelines are required to supply a portion of the air to the outer pipe of the fuel injector, which complicates the structure of the burner.

[0010] In view of the above, the object of at least one embodiment of the present disclosure is to provide a fuel injector that can improve the reliability of the burner, a burner having the fuel injector, and a gas turbine having the burner.

[0011] Solution for solving the problem

[0012] To achieve the above objectives, the fuel injector of this disclosure has a body portion extending axially, wherein the body portion includes: an axial flow path formed to extend along the axial direction; a radial flow path formed to communicate with the axial flow path at one end and open at the other end on the outer surface of the body portion; and an internal flow path including a first opening and a second opening on the outer surface, and formed to extend from the first opening to the second opening inside the body portion, wherein when the body portion is viewed in a manner opposite to a third opening of the radial flow path on the outer surface, the first opening and the second opening are located on opposite sides of the third opening of the radial flow path on the outer surface in a circumferential direction centered on the axis of the body portion.

[0013] Invention Effects

[0014] According to the fuel injector disclosed herein, the possibility of stagnation in the flow of air and fuel in the downstream region of the fuel injector can be reduced, thereby improving the reliability of the burner. Attached Figure Description

[0015] Figure 1 This is a diagram that briefly illustrates the structure of a gas turbine according to one embodiment of the present disclosure.

[0016] Figure 2 This is a cross-sectional view of a burner according to one embodiment of the present disclosure.

[0017] Figure 3 This is a side view of a combustion injector according to one embodiment of the present disclosure.

[0018] Figure 4 It is along Figure 3 A cross-sectional view along line IV-IV.

[0019] Figure 5 It is along Figure 3 A cross-sectional view of the VV line.

[0020] Figure 6 Is Figure 3 The diagram viewed from the direction of arrow VI.

[0021] Figure 7 Is Figure 3 The diagram viewed from the direction of arrow VII.

[0022] Figure 8 It is relative to Figure 4 The sectional view shown is a diagram in which the axis of any flow path of one branch of the internal flow path and the axis of the main body are unfolded on an imaginary plane.

[0023] Figure 9This is a conceptual diagram illustrating the flow of air and fuel around a combustion injector according to one embodiment of the present disclosure.

[0024] Figure 10 This is a cross-sectional view of a modified example of a combustion injector according to one embodiment of the present disclosure.

[0025] Figure 11 This is a cross-sectional view of another variation of the combustion injector according to one embodiment of the present disclosure.

[0026] Figure 12 This is a cross-sectional view of another variation of the combustion injector according to one embodiment of the present disclosure. Detailed Implementation

[0027] Hereinafter, a fuel injector according to an embodiment of the present disclosure will be described based on the accompanying drawings. This embodiment illustrates one aspect of the present disclosure and is not intended to limit the disclosure; modifications can be made freely within the scope of the technical concept of the present disclosure.

[0028] <Structure of a gas turbine and burner according to one embodiment of the present disclosure>

[0029] like Figure 1 As shown, a gas turbine 1 according to one embodiment of the present disclosure includes a compressor 2 and a plurality of burners 3 (in Figure 1 Only one burner 3 and turbine 4 are shown in the diagram. The compressor 2 is configured to draw in and compress external air, i.e., atmospheric air, and supply the compressed air to the burner 3. The burner 3 is configured to use the air compressed by the compressor 2 to burn externally supplied fuel, thereby generating combustion gases. The turbine 4 is configured to receive the combustion gases generated by the burner 3 and generate rotational driving force, outputting the generated rotational driving force to the compressor 2 and external equipment such as a generator 6.

[0030] like Figure 2 As shown, the burner 3 includes an outer cylinder 11, and an inner cylinder 12 is arranged inside the outer cylinder 11 at predetermined intervals radially spaced around the axis of the outer cylinder 11. A tail cylinder 13 is connected to the front end of the inner cylinder 12. A passage for the compressor 2 (see reference) is formed between the outer cylinder 11 and the inner cylinder 12. Figure 1 ) The compressed air flows through a ring-shaped flow path 21.

[0031] Inside the inner cylinder 12, a pilot burner 14 and multiple main burners 15 arranged to surround the pilot burner 14 are disposed. The pilot burner 14 has a pilot nozzle 23, and each main burner 15 has a main nozzle 26. In the flow path 21, multiple nozzles 28 serving as fuel injectors are arranged at predetermined intervals in the circumferential direction centered on the axis of the outer cylinder 11 (i.e., the circumferential direction centered on the axis of the inner cylinder 12). Figure 2Only two bolts 28 are shown in the figure. Each bolt 28 is configured such that its base end is fixed to the outer cylinder 11 and its front end extends toward the inner cylinder 12.

[0032] <Structure of a combustion injector according to one embodiment of this disclosure>

[0033] like Figure 3 As shown, the bolt 28 has a main body portion 30 extending from the base end portion 30a to the front end portion 30b. (As...) Figure 4 As shown, the main body 30 has a double-tube structure consisting of an inner tube 31 and an outer tube 32. An axial flow path 33 and an internal flow path 35 are formed within the main body 30. The axial flow path 33 extends axially, and the internal flow path 35 includes a first opening 36 and a second opening 37 opening onto the outer surface 30c of the main body 30, extending from the first opening 36 to the second opening 37 within the main body 30. The internal flow path 35 is configured to extend in a circumferential direction (hereinafter referred to as "circumferential") centered on the axis L of the main body 30, surrounding the axial flow path 33, and includes two branch flow path portions 35a and 35b extending in opposite directions circumferentially from the first opening 36 toward the second opening 37. It should be noted that the axial flow path 33 and the internal flow path 35 are not connected.

[0034] like Figure 5 As shown, a radial flow path 34 is also formed in the main body 30. This radial flow path 34 is configured such that one end communicates with the axial flow path 33 and the other end opens onto the outer surface 30c of the main body 30. The radial flow path 34 does not connect with the internal flow path 35 (see reference). Figure 4 (Connection). A third opening 38 is formed on the outer surface 30c as an opening for the radial flow path 34. Figure 5 In this design, radial flow paths 34 include six radial flow paths 34a, 34b, 34c, 34d, 34e, and 34f, but are not limited to six; the number can be arbitrary. Furthermore, the position of each radial flow path 34 is not limited. Figure 5 In this configuration, two radial flow paths 34 (e.g., radial flow paths 34a and 34b) are formed at the same position in the axial direction, but only one radial flow path 34 can also be formed at any position in the axial direction. For example, two radial flow paths 34a and 34b (which open at different positions in the circumferential direction) can be provided near the front end 30b at the same position in the axial direction, and the other four radial flow paths 34c to 34f are respectively arranged at different positions in the axial direction on the side closer to the base end 30a than the radial flow paths 34a and 34b.

[0035] Therefore, the positions of the third openings 38a, 38b, 38c, 38d, 38e, and 38f of each of the radial flow paths 34a, 34b, 34c, 34d, 34e, and 34f on the outer surface 30c are determined based on the respective positions of the radial flow paths 34a, 34b, 34c, 34d, 34e, and 34f. Preferably, the positions of the third openings 38a, 38b, 38c, 38d, 38e, and 38f are such that the axial direction of each is located at the second opening 37 (see reference). Figure 4 The method of determining the existence of ) within the scope of existence.

[0036] like Figure 4 As shown, even when the main body 30 is viewed in a manner opposite to any of the third openings 38, such as the third opening 38c (in the direction of arrow F), the first opening 36 and the second opening 37 are located on opposite sides relative to the third opening 38c in the circumferential direction. That is, the third opening 38c is located between the first opening 36 and the second opening 37 in the circumferential direction. When the center positions of the first opening 36, the second opening 37, and the third opening 38c in the circumferential direction are set to A, B, and C, respectively, and the axis center of the main body 30 located on the axis L is set to O, the angles AOC (hereinafter referred to as angle θ1) and BOC (hereinafter referred to as angle θ2) are 45° or more and 135° or less, preferably 60° or more and 120° or less, more preferably 80° or more and 100° or less, and most preferably 90°. It should be noted that Figure 4 The structure shown depicts the optimal structure when θ1=θ2=90°.

[0037] When the circumferentially opposite opening surfaces of the outer tube 32 defining the first opening 36 are designated as opening surfaces 32a1 and 32a2, and the angle formed by the extended surfaces S1 and S2 of each of the opening surfaces 32a1 and 32a2 is designated as θ3, it is preferably 45°≤θ3≤90°. As described later, the compressor 2 (refer to...) Figure 1 A portion of the compressed air flows into the internal flow path 35 through the first opening 36. However, if θ3 is less than 45°, the circumferential opening width must be increased to allow as much air as possible to flow in, which has a limit based on the thickness of the main body 30. On the other hand, even if θ3 is greater than 90°, the effect of allowing as much air as possible to flow in cannot be expected to be better than when θ3 = 90°, and may even be reduced.

[0038] like Figure 6As shown, the internal flow path 35 includes three segmented internal flow paths 35c, 35d, and 35e that are not interconnected axially. The segmented internal flow paths 35c, 35d, and 35e each include first segmented openings 36a, 36b, and 36c that constitute the first opening 36. In this case, as... Figure 7 As shown, the internal flow paths 35c, 35d, and 35e are divided into second segmented openings 37a, 37b, and 37c, respectively, constituting the second opening 37. It should be noted that the number of segmented internal flow paths 35 is not limited to three; they can be divided into two, or even four or more. In this case, the number of segments in the first opening 36 and the second opening 37 is the same as the number of segments in the internal flow paths 35.

[0039] As described above, it is preferable to use the third opening 38a to 38f (refer to...) Figure 5 ) respectively located axially at the second opening 37 (refer to Figure 4 The manner in which the first opening 37 and the second opening 37 exist is determined, but in the case where the first opening 37 and the second opening 37 each include multiple segmented openings, such as Figure 3 As shown, the preferred structure is as follows: the third opening 38f is axially located within the range where the second segmented opening 37a exists, the third opening 38d is axially located within the range where the second segmented opening 37b exists, and the third opening 38b is axially located within the range where the second segmented opening 37c exists. Although in Figure 3 Not shown in the figure, but preferably with the following structure: third openings 38a, 38c, 38e (refer to...) Figure 5 They are also located in the axial direction within the range where the second dividing openings 37c, 37b, and 37a exist.

[0040] contrast Figure 6 and Figure 7 The first opening 36 and the second opening 37 each have the same circumferential opening width, but the latter has a smaller axial opening width than the former. Therefore, the opening area of ​​the second opening 37 is smaller than the opening area of ​​the first opening 36. Consequently, the internal flow path 35, i.e., the divided internal flow paths 35c, 35d, and 35e, can be configured such that they extend from the first opening 36 toward the second opening 37, or from a position between the first opening 36 and the second opening 37 toward the second opening 37, thus reducing the flow path area.

[0041] For such a structure related to the opening areas of the first opening 36 and the second opening 37, if the axial opening width and the circumferential opening width of the first opening 36 are respectively set as w 1a and w 1p Let the axial opening width and the circumferential opening width of the second opening 37 be w respectively. 2aand w 2p The preferred option is (w) 1a / w 2a )>(w 1p / w 2p ).

[0042] based on Figure 8 An example of a structure for reducing the flow area of ​​the internal flow path 35 from the position between the first opening 36 and the second opening 37 toward the second opening 37 will be described. Figure 8 It is relative to Figure 4 The sectional view shown ( Figure 8 (The left side of the diagram) is a diagram showing the cross-sectional plane CS of one branch flow path 35b of the internal flow path 35 along the axis L of any flow path FS and the axis L of the main body 30 unfolded on an imaginary plane. Figure 8 The diagram on the right, hereinafter referred to as the "developed diagram", and the shape shown in the developed diagram, hereinafter referred to as the "developed shape").

[0043] The branch flow path 35b is divided into a first flow path 35b1, which is the upstream portion extending from the first opening 36 towards the second opening 37, and a second flow path 35b2, which is the downstream portion. The flow path FS corresponding to the first flow path 35b1 is designated as FS1, and the flow path FS corresponding to the second flow path 35b2 is designated as FS2. In the above unfolded diagram, the angle formed by the direction R1 of the flow path FS1 of the first flow path 35b1 with respect to the axis L is designated as θa, and the angle formed by the direction R2 of the flow path FS2 of the second flow path 35b2 with respect to the axis L is designated as θb. The simplest structure of the branch flow path 35b is 0° < θa = θb < 90°, which is equivalent to... Figure 3 The structure shown is such that, in this structure, the branch flow path 35b extends from the first opening 36 to the second opening 37 at a constant angle relative to the axis L.

[0044] exist Figure 8 The example shown is not the simplest structure, but rather an example of a structure where θb < θa. That is, it becomes the following structure: the second flow path 35b2 faces the front end 30b relative to the first flow path 35b1 (see reference). Figure 3 )(exist Figure 8In the middle, it bends in the depth direction perpendicular to the paper surface. With such a structure (both the structure of 0°<θa=θb<90° and the structure of θb<θa), it is possible to achieve a structure in which the flow path area of ​​the internal flow path 35 is reduced from the position between the first opening 36 and the second opening 37 toward the second opening 37, that is, a structure in which the flow path area of ​​the second flow path 35b2 is reduced. In addition, by the structure in which the second flow path 35b2 bends toward the front end 30b relative to the first flow path 35b1, it is possible to make the second opening 37 be in the same axial position as the third opening 38 for injecting fuel.

[0045] It should be noted that, in Figure 8 In the diagram, θa is depicted as 90°, but it is not limited to this shape. Even at any angle where θa < 90°, as long as θb < θa, it is possible to achieve a structure in which the flow path area of ​​the internal flow path 35 decreases from the position between the first opening 36 and the second opening 37 toward the second opening 37.

[0046] exist Figure 6 In the text, the first dividing openings 36a to 36c are depicted as having the same opening area, but this is not a limitation. At least two of the opening areas of the first dividing openings 36a to 36c may also be different from each other. For example, relative to... Figure 5 In the case where the radial flow paths 34c and 34e are absent, and therefore the third openings 38c and 38e are also absent, the opening area of ​​the first segmented opening 36c of the first opening 36, located closest to the front end 30b, which divides the internal flow path 35e, can be larger than the opening areas of the first segmented openings 36a and 36b of the other internal flow paths 35c and 35d. In this case, the second segmented openings 37a and 37b of the internal flow paths 35c and 35d (refer to...) Figure 7 Within the axially existing range, there are third openings 38f and 38d respectively (refer to...). Figure 5 However, in the second dividing opening 37c of the dividing internal flow path 35e (refer to...) Figure 7 Within the axially existing range, there are two third openings 38a and 38b (refer to...). Figure 5 That is, the opening area of ​​the third opening 38 that exists in the axial direction of the second dividing opening 37c is greater than the opening area of ​​the third opening 38 that exists in the other two ranges.

[0047] As will be described later, fuel flows in axial path 33 (refer to...) Figure 4 and 5 After flowing through the middle, it is injected from the third opening 38 and is compressed by the compressor 2 (see reference). Figure 1A portion of the compressed air flows into the internal flow paths 35c, 35d, and 35e of the segment via the first segmentation openings 36a, 36b, and 36c, respectively, and then flows through the second segmentation openings 37a, 37b, and 37c (see reference). Figure 7 The fuel flows out from the internal flow path 35, but it is believed that the amount of fuel injected in the axial direction of the second segmented opening 37c is greater than the axial direction of the second segmented openings 37a, 37b. Conversely, by making the opening areas of each of the first segmented openings 36a, 36b, 36c the structure described above, the amount of air flowing into the segmented internal flow path 35e, which corresponds to the latter range, is greater than that in the other segmented internal flow paths 35c, 35d.

[0048] For such a structure related to the opening areas of the first opening 36 and the second opening 37, if the opening area of ​​the second segmented opening 37c, which is the range of the third opening 38a, 38b, and 38f within the range where the second segmented openings 37a to 37c exist respectively in the axial direction, is defined as S, then the opening area of ​​the second segmented opening 37c within the range where the third openings 38a and 38b are located is S. 2L Let the opening area of ​​the first dividing opening 36c corresponding to the second dividing opening 37c be S. 1L Let S be the opening area of ​​each of the second segmented openings 37a and 37b that define the ranges of the other third openings 38f and 38d. 2S Let the opening area of ​​the first segmented openings 36a and 36b corresponding to these second segmented openings 37a and 37b be S. 1S The preferred option is (S) 1L / S2L)>(S 1S / S 2S ).

[0049] like Figure 7 As shown, the opening areas of the second segmented openings 37a, 37b, and 37c are all identical. As described later, the compressor 2 (refer to...) Figure 1 A portion of the compressed air flows into the internal flow path 35 through the first opening 36 and then flows out of the internal flow path 35 through the second opening 37. However, the amount of air flowing out from each of the second segmented openings 37a, 37b, and 37c can be adjusted by the opening area of ​​each of the first segmented openings 36a, 36b, and 36c corresponding to each of the second segmented openings 37a, 37b, and 37c, thus simplifying the design of the bolt 28.

[0050] It should be noted that even if the opening areas of the second dividing openings 37a, 37b, and 37c are all the same, they are not required to be exactly the same. Even if they are slightly different, it is sufficient that they are approximately the same. As for the degree of difference, for example, the ratio of the opening area of ​​each of the second dividing openings 37a, 37b, and 37c to the average opening area of ​​the second dividing openings 37a, 37b, and 37c only needs to be between 0.8 and 1.2.

[0051] Operation of a gas turbine, burner, and combustion injector according to one embodiment of this disclosure.

[0052] like Figure 1 As shown, during the operation of the gas turbine 1, air is generated and compressed by the compressor 2. This air is then introduced into the combustor 3. Inside the combustor 3, fuel is mixed with the compressed air, and the mixture is burned to generate high-temperature, high-pressure combustion gas. The combustion gas is then introduced into the turbine 4 to drive the turbine 4, which in turn outputs the rotational driving force generated by the turbine 4 to the compressor 2 and external equipment (such as the generator 6).

[0053] like Figure 2 As shown, the air introduced into the burner 3 flows into the inner cylinder 12 through the flow path 21, where it mixes with the fuel supplied from the pilot nozzle 23 and the main nozzle 26 to form a mixture. The mixture is then burned to generate combustion gases. As the air passes through the flow path 21, it passes through the plug 28, but fuel is also supplied from the plug 28 at this time, and the air and fuel are mixed.

[0054] like Figure 5 As shown, fuel supplied to the plug 28 from a supply source not shown flows from the base end 30a side toward the front end 30b side in the axial flow path 33, and is distributed to radial flow paths 34a to 34f respectively, and injected into flow path 21 from the third openings 38a to 38f respectively. On the other hand, as Figure 9 As shown, the air flowing in the flow path 21 branches off to both sides of the plug 28 as it passes through the plug 28. At this time, fuel injected from the third openings 38a and 38b, for example, branches off to both sides of the plug 28 and mixes with the air passing through the plug 28, merging downstream of the plug 28 in the direction of airflow. In the region between the point where the air and fuel branching off to the plug 28 merge downstream of the plug 28 and the plug 28 itself—that is, region K on the back side of the plug 28 when viewed in the direction of airflow—air and fuel sometimes stagnate, forming a stagnant flow of air and fuel. If air and fuel stagnate in region K, it becomes burner 3 (see reference). Figure 2 The reason for the reduced reliability of )

[0055] However, when using the plug 28, if the plug 28 is configured so that the first opening 36 is opposite to the direction of airflow, when air passes through the plug 28, a portion of the air flows through the first opening 36 in the internal flow path 35 and exits through the second opening 37. Depending on the positional relationship between the first opening 36 and the second opening 37 in the plug 28, since the second opening 37 faces region K, the air exiting from the internal flow path 35 via the second opening 37 flows towards region K. Therefore, even if air and fuel become stagnant in region K, the air exiting from the internal flow path 35 towards region K will push the air and fuel that are about to be stagnant in region K downstream, thus reducing the possibility of stagnation of air and fuel flow in region K.

[0056] like Figure 6 and Figure 7 As shown, in the plug 28, the opening area of ​​the second opening 37 is smaller than that of the first opening 36. Therefore, the air velocity flowing out of the second opening 37 is greater than the air velocity flowing into the first opening 36. Consequently, compared to the case where the opening areas of the second opening 37 and the first opening 36 are the same, the ability to push the air and fuel trapped in region K is increased, thus further reducing the possibility of stagnation in the flow of air and fuel. Furthermore, as... Figure 8 As shown, by making the flow path area of ​​the second flow path 35b2 decrease towards the second opening 37, the flow velocity of the air flowing in the second flow path 35b2 gradually increases, thus suppressing unnecessary turbulence in the flow of air flowing out of the second opening 37.

[0057] If, in the configuration of the bolt 28, the opening area of ​​the first segmented opening 36c of the segmented internal flow path 35e, located closest to the front end 30b, is larger than the opening areas of the first segmented openings 36a and 36b of the other segmented internal flow paths 35c and 35d, and the third opening 38f is axially located within the range where the second segmented opening 37a exists, the third opening 38d is axially located within the range where the second segmented opening 37b exists, and the third openings 38a and 38b are axially located within the range where the second segmented opening 37c exists, then the amount of air flowing into the segmented internal flow path 35e is greater than the amount of air flowing into the segmented internal flow paths 35c and 35d, respectively. Figure 9As shown, in the plug 28, the air flowing out of the second opening 37 inhibits the retention of the fuel-air mixture flowing out of the third opening 38 in region K. As described above, in the structure where the third opening 38 includes four third openings 38a, 38b, 38d, and 38f, the total amount of fuel flowing out of the third openings 38a and 38b is greater than the amount of fuel flowing out of the third openings 38c and 38d, respectively. Therefore, when fuel and air are retained in region K, the fuel concentration in the retained mixture becomes higher, which affects the burner 3 (refer to...). Figure 2 The adverse effects on the reliability of the airflow become greater. However, since the amount of air flowing into the internal flow path 35e of the segment is greater than the amount of air flowing into the other internal flow paths 35c and 35d, the ability to push away the air and fuel trapped in region K also increases. As a result, the possibility of stagnation in the flow of air and fuel is reduced, as it can push away the air and fuel trapped in region K.

[0058] As described above, in the bolt 28, the third opening 38 is located axially within the area where the second opening 37 exists in the main body 30. According to this structure, the flow path 35 (see reference 28) flows through the second opening 37. Figure 4 The outflowing air passes through region K, where a third opening 38 exists in the axial direction, thus pushing away the air and fuel trapped in region K and reducing the possibility of stagnation in the flow of air and fuel.

[0059] It should be noted that in the bolt 28, the internal flow path 35 has two branch flow path sections 35a and 35b, but it can also be a structure that has only one of the branch flow path sections 35a and 35b.

[0060]

[0061] exist Figure 9 In the diagram, the inner wall surfaces 35c1 and 35c2 that define the internal flow path 35c, the inner wall surfaces 35d1 and 35d2 that define the internal flow path 35d, and the inner wall surfaces 35e1 and 35e2 that define the internal flow path 35e are depicted as flat surfaces, but are not limited to flat surfaces. They can also be smooth curved surfaces, or surfaces with steps, protrusions, etc.

[0062] like Figure 10As shown, the inner tube 31 may also include a protrusion 60 protruding from the outer surface 31a of the inner tube 31 toward the second opening 37 within the opening range of the second opening 37. The protrusion 60 preferably has the following structure: a surface portion 61 formed by reversing the bending direction midway through the outer surface 31a1 of the outer surface 31a toward the protrusion 60, and a surface portion 62 formed by reversing the bending direction midway through the outer surface 31a2 of the outer surface 31a toward the protrusion 60, both forming a cross-sectional shape that tapers toward the second opening 37. According to this structure, air flowing near the outer surfaces 31a1 and 31a2 respectively flows along the surface portions 61 and 62 toward the second opening 37, thus suppressing flow turbulence that may occur when air flowing through the branch flow paths 35a and 35b merges, and thus suppressing flow turbulence that may be contained in the air flowing out of the second opening 37.

[0063] like Figure 11 As shown, the third opening 38 may also protrude beyond the outer surface 30c of the main body 30. Figure 11 In this design, only the third opening 38c is depicted as protruding beyond the outer surface 30c, but the other third openings 38a, 38b, 38d, 38e, and 38f can also have the same structure. Furthermore, several of the multiple third openings 38 can also have this structure.

[0064] The fuel injector disclosed herein is not limited to the structure of plug 28. Any structure is permissible as long as the air flowing from the internal flow path within the plug can propel the air and fuel retained in region K. Figure 12 The structure of a combustion injector according to other embodiments is illustrated.

[0065] exist Figure 12 In the illustrated plug 48, the axial flow path 53 formed in the main body 50 has an axial direction (with) the main body 50. Figure 12The axial flow path 53 is partially divided into two segmented axial flow paths 53a and 53b in the direction perpendicular to the paper. The axial flow path 53 may also have two or more segmented axial flow paths 53a and 53b at different positions along the axial direction of the main body 50. Furthermore, radial flow paths 54a and 54b are formed in the main body 50, with one end connected to the segmented axial flow paths 53a and 53b respectively, and the other end opening on the outer surface 50c of the main body 50. It should be noted that only one of the radial flow paths 54a and 54b may be formed. Additionally, an internal flow path 55 is formed in the main body 50, which is formed by dividing the axial flow paths 53a and 53b. The openings at both ends of the internal flow path 55, which open onto the outer surface 50c of the main body 50, are designated as a first opening 56 and a second opening 57, respectively. The openings of the radial flow paths 54a and 54b, which open onto the outer surface 50c of the main body 50, are designated as third openings 58a and 58b, respectively. It should be noted that by configuring the axial flow path 53 with two or more segments 53a and 53b at different axial positions, it is possible to form two or more internal flow paths 55 at different axial positions within the main body 50.

[0066] In sluice gate 48, a portion of the air flowing toward sluice gate 48 flows into the internal flow path 55 through the first opening 56, while the remaining air branches off to both sides of sluice gate 48. At this time, fuel injected from the third openings 58a and 58b respectively branches off to both sides of sluice gate 48 and mixes with the air passing through sluice gate 48, merging on the downstream side of sluice gate 48 in the direction of airflow. In sluice gate 48, the air flowing out of the internal flow path 55 through the second opening 57 also flows toward the area on the back side of sluice gate 48 when viewed in the direction of airflow. Therefore, even if air and fuel want to remain in the area on the back side of sluice gate 48, they will be pushed by the air flowing out of the second opening 57.

[0067] However, in bolt 48, compared with bolt 28 (see reference) Figure 4 Unlike the first opening 56, the second opening 57, circumferentially centered on the axis L' of the main body 50, has a smaller opening width than the first opening 56, thus making the opening area of ​​the second opening 57 smaller than the opening area of ​​the first opening 56. Therefore, it is possible to form an area equivalent to... Figure 9 Therefore, in plug 28, compared with plug 48, the possibility of stagnation forming in region K can be further reduced.

[0068] In the burner 3 and the gas turbine 1, a plug 28 or 48 is used as a fuel injection device that constitutes the top hat nozzle of the flow path 21 provided in the burner 3. This reduces the possibility of stagnation in the flow of air and fuel, and thus prevents the structure of the burner 3 and the gas turbine 1 from becoming complicated.

[0069] In the above embodiments, the cross-sectional shape of the main body portions 30 and 50 is circular, but it is not limited to this shape and can also be any cross-sectional shape such as ellipse, polygon, or wing shape. In this case, a line passing through the centroid of any cross-sectional shape and extending along the respective axial direction of the main body portions 30 and 50 can be used as the respective axis L and L' of the main body portions 30 and 50.

[0070] The contents described in the above embodiments shall be understood as follows.

[0071] [1] One embodiment of the fuel injector is a fuel injector (plug 28, 48) having a body portion (30, 50) extending axially.

[0072] The main body (30, 50) includes:

[0073] Axial flow paths (33, 53) are formed to extend along the said axial direction;

[0074] Radial flow paths (34, 54a, 54b) are formed such that one end communicates with the axial flow path (33, 53), and the other end opens into the outer surface (30c, 50c) of the main body (30, 50); and

[0075] The internal flow path (35, 55) includes a first opening (36, 56) and a second opening (37, 57) opening on the outer surfaces (30c, 50c), and is formed to extend from the first opening (36, 56) to the second opening (37, 57) inside the main body (30, 50).

[0076] The first opening (36, 56) and the second opening (37, 57) are located on opposite sides of the third opening (38, 58a, 58b) which opens on the outer surface (30c, 50c) relative to the radial flow path (34, 54a, 54b) in the circumferential direction centered on the axis (L) of the main body (30, 50).

[0077] According to the fuel injector disclosed herein, the possibility of stagnation in the flow of air and fuel in the downstream region of the fuel injector can be reduced, thereby improving the reliability of the burner.

[0078] [2] Another fuel injector design is based on the fuel injector design in [1].

[0079] The opening area of ​​the second opening (37, 57) is smaller than the opening area of ​​the first opening (36, 56).

[0080] With this structure, the air velocity flowing out from the second opening is greater than the air velocity flowing into the first opening. Therefore, the ability to push the air and fuel trapped in the downstream area of ​​the fuel injector is increased, which further reduces the possibility of stagnation and improves the reliability of the burner.

[0081] [3] Another fuel injector design is based on the fuel injector design of [1] or [2].

[0082] The axial opening width of the second opening (37, 57) is smaller than the axial opening width of the first opening (36, 56).

[0083] With this structure, the circumferential opening width of the second opening is not smaller than that of the first opening, thus reducing the possibility of stagnation of air and fuel flow on both sides of the second opening in the circumferential direction, thereby improving the reliability of the burner.

[0084] [4] Another fuel injector scheme is based on the fuel injector of any one of [1] to [3].

[0085] The main body (30) includes a front end portion (30b) and a base end portion (30a).

[0086] The internal flow path (35) includes multiple segmented internal flow paths (35c, 35d, 35e) that are not interconnected in the axial direction.

[0087] The plurality of segmented internal flow paths (35c, 35d, 35e) each include a first segmented opening (36a, 36b, 36c) constituting the first opening (36).

[0088] The opening area of ​​the first segmented opening (36c) of the internal flow path (35e) located closest to the front end (30b) among the plurality of segmented internal flow paths (35c, 35d, 35e) is greater than the opening area of ​​the first segmented opening (36a, 36b) of the other internal flow paths (35c, 35d).

[0089] In a main body with multiple third openings at different axial positions, if the number of third openings near the front end is greater than the number of third openings at other positions, the fuel injection amount near the front end is greater than the fuel injection amount at other positions. In this regard, according to the structure described above [4], the amount of air flowing into the internal flow path closest to the front end is greater than the amount of air flowing into the other internal flow paths, and the amount of air flowing out of the internal flow path closest to the front end is greater than the amount of air flowing out of the other internal flow paths. Therefore, it is possible to push the air and fuel stagnating in the downstream area of ​​the fuel injector near the front end, and reduce the possibility of stagnation in the flow of air and fuel.

[0090] [5] Another fuel injector scheme is based on the fuel injector of any one of [1] to [4].

[0091] The main body (30) includes a front end portion (30b) and a base end portion (30a).

[0092] The internal flow path (35) includes multiple segmented internal flow paths (35c, 35d, 35e) that are not interconnected in the axial direction.

[0093] The plurality of segmented internal flow paths (35c, 35d, 35e) each include second segmented openings (37a, 37b, 37c) that constitute the second opening (37).

[0094] The ratio of the opening area of ​​each of the plurality of second dividing openings (37a, 37b, 37c) to the average opening area of ​​the plurality of second dividing openings (37a, 37b, 37c) is 0.85 to 1.2.

[0095] With this structure, the opening areas of each of the second segmented openings are approximately the same. Therefore, the amount of air flowing out from each of the second segmented openings can be adjusted by the opening area of ​​each of the first segmented openings corresponding to each of the second segmented openings, thus simplifying the design of the fuel injector.

[0096] [6] Another fuel injector scheme is based on the fuel injector of any one of [1] to [5],

[0097] The third opening (38) is located in the axial direction within the range where the second opening (37) exists.

[0098] When air and fuel are trapped in the downstream region of the fuel injector, the amount of trapped air and fuel in the downstream region of the fuel injector at the location of the third opening in the axial direction increases. In response to this, according to the structure described above [6], the air flowing out from the internal flow path through the second opening passes through the downstream region of the fuel injector at the location of the third opening in the axial direction, thereby pushing the air and fuel trapped in the downstream region of the fuel injector, thereby reducing the possibility of stagnation in the flow of air and fuel.

[0099] [7] Another fuel injector design is based on the fuel injector design of [6].

[0100] The internal flow path (35) includes a plurality of segmented internal flow paths (35c, 35d, 35e) that are not interconnected in the axial direction. The plurality of segmented internal flow paths (35c, 35d, 35e) respectively include a first segmented opening (36a, 36b, 36c) constituting the first opening (36) and a second segmented opening (37a, 37b, 37c) constituting the second opening (37).

[0101] If we define the opening area of ​​the second segmented opening (37c) within the range where the third openings (38a, 38b, 38c, 38d) of the plurality of second segmented openings (37a, 37b, 37c) exist respectively along the axial direction as S, then the opening area of ​​the second segmented opening (37c) within the range containing the third opening (38a, 38b) with the largest opening area is defined as S. 2L Let the opening area of ​​the first segmented opening (36c) corresponding to the second segmented opening (37c) be S. 1L Let S be the opening area of ​​the second dividing opening (37a, 37b) that defines the range of the other third openings (38c, 38d). 2s Let the opening area of ​​the first segmented opening (36a, 36b) corresponding to the second segmented opening (37a, 37b) be S. 1s Then (S) 1L / S 2L )>(S 1s / S 2S ).

[0102] This structure is a more preferred structure than [6] above, and therefore the effects of [6] above can be obtained.

[0103] [8] Another fuel injector scheme is based on the fuel injector of any one of [1] to [7],

[0104] If the axial opening width and the circumferential opening width of the first opening (36) are respectively set as w1a and w 1p The axial opening width and the circumferential opening width of the second opening (37) are respectively set as w. 2a and w 2p Then (w 1a / w 2a )>(w 1p / w 2p ).

[0105] This structure is a more preferred structure than those described in [1] to [7], and thus the effects of [1] to [7] can be obtained.

[0106] [9] Another fuel injector scheme is based on the fuel injector of any one of [1] to [8],

[0107] The internal flow path (35) extends in such a way that it surrounds the axial flow path (33) on the radially inner side of the main body (30).

[0108] With this structure, the circumferential opening width of the second opening can be maximized. If the circumferential opening width of the second opening is short, stagnation points will form on both sides of the second opening in the circumferential direction. In this regard, with the structure described above [9], the possibility of stagnation points forming in the downstream region of the fuel injector can be further reduced.

[0109]

[10] Another fuel injector design is based on the fuel injector design of [9].

[0110] The internal flow path (35) includes:

[0111] A first flow path (35b1) extends circumferentially from the first opening (36) toward the second opening (37); and

[0112] The second flow path (35b2) extends circumferentially from the end of the first flow path (35b1) on the side opposite to the first opening (36) to the second opening (37).

[0113] In the unfolded shape of the first flow path (35b1) and the second flow path (35b2) along the axis (L) and the axis (L) unfolded on an imaginary plane from the first opening (36) to the second opening (37), the angle (θb) formed by the extension direction (R2) of the second flow path (35b2) with respect to the axis (L) is smaller than the angle (θa) formed by the extension direction (R1) of the first flow path (35b1) with respect to the axis (L).

[0114] With this structure, a fuel injector can be formed such that the opening area of ​​the second opening is smaller than the opening area of ​​the first opening. Furthermore, with this structure, the second opening can also be positioned axially at the same location as the third opening for fuel injection.

[0115]

[11] Another fuel injector scheme is based on the fuel injector of any one of [1] to

[10] ,

[0116] The internal flow path (35) is configured such that the flow path area decreases from the first opening (36) toward the second opening (37).

[0117] With this structure, the air velocity flowing in the second flow path increases toward the second opening, thus increasing the ability to push the air and fuel stagnant in the downstream area of ​​the fuel injector, and further reducing the possibility of stagnation in the flow of air and fuel.

[0118]

[12] Another fuel injector scheme is based on the fuel injector of any one of [1] to

[11] ,

[0119] The internal flow path is configured such that the axial opening width of the flow path cross-section decreases from the first opening toward the second opening.

[0120] With this structure, the circumferential opening width of the second opening will not be smaller than the circumferential opening width of the first opening. It can be a structure in which the flow area of ​​the internal flow path 35 decreases from the first opening 36 toward the second opening 37. Therefore, it can reduce the possibility of stagnation forming on both sides of the second opening 57 in the circumferential direction, and can increase the ability to push the air and fuel stagnating in the downstream area of ​​the fuel injector, and can further reduce the possibility of stagnation forming in the flow of air and fuel.

[0121]

[13] Another fuel injector scheme is based on the fuel injector of any one of [1] to

[12] ,

[0122] The internal flow path (35) includes two branch flow path sections (35a, 35b) extending in opposite directions in the circumferential direction from the first opening (36) toward the second opening (37).

[0123] With this structure, the circumferential opening width of the second opening can be maximized. If the circumferential opening width of the second opening is short, stagnation of air and fuel flow will form on both sides of the circumferential direction of the second opening. In this regard, with the structure described above

[13] , the possibility of stagnation forming in the downstream region of the fuel injector can be further reduced.

[0124]

[14] One embodiment of the burner has a fuel injector (28, 48) of any one of [1] to

[13] .

[0125] According to the fuel injector disclosed herein, by using any one of the fuel injectors in [1] to

[13] , the possibility of stagnation in the flow of air and fuel can be reduced, thus preventing the structure of the burner from becoming complicated.

[0126]

[15] One proposed gas turbine configuration includes:

[0127] Compressor (2);

[0128]

[14] burner (3); and

[0129] Turbine (4).

[0130] According to the fuel injector disclosed herein, by using the burner of

[14] , the possibility of stagnation in the flow of air and fuel can be reduced, thus preventing the structure of the gas turbine from becoming complicated.

[0131] Explanation of reference numerals in the attached figures:

[0132] 1...gas turbine;

[0133] 2...compressor;

[0134] 3...burner;

[0135] 4... Turbine;

[0136] 28... Plug (fuel injector);

[0137] 30...Main body;

[0138] 30a...(the base end of the main body);

[0139] 30b...(the front end of the main body);

[0140] 30c... (outer surface of the main body);

[0141] 33...Axial flow path;

[0142] 34...Radial flow path;

[0143] 34a...radial flow path;

[0144] 34b...radial flow path;

[0145] 34c...radial flow path;

[0146] 34d...radial flow path;

[0147] 35...Internal flow path;

[0148] 35a...Branch Flow Path Section;

[0149] 35b...Branch Flow Path Section;

[0150] 35b1...First flow path part;

[0151] 35b2...Second flow path section;

[0152] 35c...Divide the internal flow path;

[0153] 35d...divided internal flow path;

[0154] 35e...Divide internal flow path;

[0155] 36...First opening;

[0156] 36a...First dividing opening;

[0157] 36b...First dividing opening;

[0158] 36c...First dividing opening;

[0159] 37...Second opening;

[0160] 37a...Second dividing opening;

[0161] 37b...Second dividing opening;

[0162] 37c...Second dividing opening;

[0163] 38...Third opening;

[0164] 38a...Third opening;

[0165] 38b...Third opening;

[0166] 38c...Third opening;

[0167] 38d... third opening;

[0168] 48... Plug (fuel injector);

[0169] 50...Main body;

[0170] 50c... (outer surface of the main body);

[0171] 53...Axial flow path;

[0172] 54...radial flow path;

[0173] 54a...radial flow path;

[0174] 54b...radial flow path;

[0175] 55...Internal flow path;

[0176] 56...First opening;

[0177] 57...Second opening;

[0178] 58a... Third opening;

[0179] 58b...Third opening;

[0180] CS...cutting plane;

[0181] L...(the axis of the main body);

[0182] L'... (the axis of the main body).

Claims

1. A fuel injector having a body portion extending axially, wherein, The main body includes: An axial flow path is formed to extend along the axial direction; A radial flow path, which is formed such that one end communicates with the axial flow path and the other end opens on the outer surface of the main body; and An internal flow path includes a first opening and a second opening on the outer surface, and is formed to extend from the first opening to the second opening inside the main body. The radial flow path is not connected to the internal flow path. The first opening and the second opening are located on opposite sides of the third opening on the outer surface, which is located relative to the radial flow path, in the circumferential direction centered on the axis of the main body. The main body includes a front end and a base end. The internal flow path includes multiple segmented internal flow paths that are not interconnected in the axial direction. The plurality of segmented internal flow paths each include a first segmented opening that constitutes the first opening. The opening area of ​​the first segmented opening of the internal flow path located closest to the front end among the plurality of segmented internal flow paths is larger than the opening area of ​​the first segmented opening of the other internal flow paths.

2. The fuel injector according to claim 1, wherein, The opening area of ​​the second opening is smaller than the opening area of ​​the first opening.

3. The fuel injector according to claim 1 or 2, wherein, The axial opening width of the second opening is smaller than the axial opening width of the first opening.

4. The fuel injector according to claim 1 or 2, wherein, The plurality of segmented internal flow paths each include a second segmented opening that constitutes the second opening. The ratio of the opening area of ​​each of the plurality of second segmented openings to the average opening area of ​​the plurality of second segmented openings is 0.8 to 1.

2.

5. The fuel injector according to claim 1 or 2, wherein, The third opening is located axially within the range where the second opening exists.

6. The fuel injector according to claim 5, wherein, The plurality of segmented internal flow paths each include a second segmented opening that constitutes the second opening. If we define the area of ​​the second segmented opening within the range of the third opening that has the largest opening area among the multiple second segmented openings in the axial direction as S, then... 2L Let the area of ​​the opening be S. 2L Let the opening area of ​​the first segmented opening corresponding to the second segmented opening be S. 1L Let S be the opening area of ​​the second segmented opening that defines the range of the other third openings. 2S Let the area of ​​the opening be S. 2S Let the opening area of ​​the first segmented opening corresponding to the second segmented opening be S. 1S Then (S) 1L / S 2L ) > (S 1S / S 2S ).

7. The fuel injector according to claim 1 or 2, wherein, If we define the axial opening width and the circumferential opening width of the first opening as w respectively... 1a and w 1p Let the axial opening width and the circumferential opening width of the second opening be w respectively. 2a and w 2p Then (w 1a / w 2a ) > (w 1p / w 2p ).

8. The fuel injector according to claim 1 or 2, wherein, The internal flow path extends in such a way that it surrounds the axial flow path on the radially inner side of the main body.

9. The fuel injector according to claim 8, wherein, The internal flow path includes: A first flow path portion, which extends circumferentially from the first opening portion toward the second opening portion; and The second flow path extends circumferentially from the end of the first flow path on the side opposite to the first opening to the second opening. In the unfolded shape of the first flow path portion and the second flow path portion along the axis and the axis on an imaginary plane from the first opening to the second opening, the angle between the extension direction of the second flow path portion and the axis is smaller than the angle between the extension direction of the first flow path portion and the axis.

10. The fuel injector according to claim 1 or 2, wherein, The internal flow path is configured such that the flow path area decreases from the first opening toward the second opening.

11. The fuel injector according to claim 1 or 2, wherein, The internal flow path is configured such that the axial opening width of the flow path cross-section decreases from the first opening toward the second opening.

12. The fuel injector according to claim 1 or 2, wherein, The internal flow path includes two branch flow path sections extending in opposite directions in the circumferential direction from the first opening toward the second opening.

13. The fuel injector according to claim 1, wherein, Air flows into the internal flow path through the first opening and flows out of the internal flow path through the second opening.

14. A burner, wherein, The burner comprises the fuel injector according to any one of claims 1 to 13.

15. A gas turbine, wherein, The gas turbine includes: compressor; The burner as claimed in claim 14; and Turbine.

Images