Two-stage combustion nozzle, and gas turbine combustor

Abstract

This two-stage combustion nozzle is configured to inject air and fuel into a combustion chamber defined by a combustion cylinder of a gas turbine, and comprises a nozzle body attached to a side wall of the combustion cylinder. The nozzle body includes: a first end surface, which is an end surface disposed on the inner peripheral side of the side wall and facing the combustion chamber; a second end surface opposite to the first end surface; and a plurality of nozzle flow paths each extending between the first end surface and the second end surface. The plurality of nozzle flow paths each have: an injection port for injecting air and fuel and formed in the first end surface; an introduction port for introducing air formed in the second end surface; and a flow path surface connected to the introduction port and the injection port and having formed therein at least one fuel injection port for injecting fuel.

Description

Two-stage combustion nozzle and gas turbine combustor

[0001] The present disclosure relates to a two-stage combustion nozzle and a gas turbine combustor for injecting a mixed fluid containing fuel and air into a two-stage combustion region in a combustion chamber of a gas turbine. This application claims priority to Japanese Patent Application No. 2024-092733, filed on June 7, 2024, with the Japan Patent Office, the contents of which are incorporated herein by reference.

[0002] Conventionally, gas turbine combustors employing a two-stage combustion system have been known. For example, a two-stage combustion nozzle disclosed in Patent Document 1 includes an outlet member having an outlet opening communicating with a two-stage combustion region, two air passages arranged upstream of the outlet member, and a plurality of fuel plenums communicating with either of the two air passages. A mixed fluid of air and fuel is generated in each air passage. At the outlet opening, the mixed fluids flowing through the two air passages join together and flow toward the two-stage combustion region.

[0003] Japanese Patent Application Laid-Open No. 2019-082313

[0004] In the above-described two-stage combustion nozzle, flow stagnation may occur at the outlet opening where the mixed fluids meet. If the fuel contained in the stagnant mixed fluid ignites inside the two-stage combustion nozzle, abnormal combustion may occur. For example, if a highly flammable fuel such as hydrogen fuel is used in the two-stage combustion nozzle, abnormal flame holding, in which the flame remains inside the two-stage combustion nozzle, or flashback, in which the flame flows back from the two-stage combustion region into the two-stage combustion nozzle, may occur.

[0005] An object of the present disclosure is to provide a two-stage combustion nozzle and a gas turbine combustor that can suppress abnormal combustion.

[0006] A two-stage combustion nozzle according to at least one embodiment of the present disclosure is a two-stage combustion nozzle configured to inject air and fuel into a combustion chamber defined by a combustion liner of a gas turbine, the two-stage combustion nozzle comprising: a nozzle body attached to a side wall of the combustion liner, the nozzle body including: a first end face disposed on the inner periphery of the side wall and facing the combustion chamber; a second end face opposite to the first end face; and a plurality of nozzle flow paths each extending between the first end face and the second end face, each of the plurality of nozzle flow paths having: an injection port formed in the first end face for injecting the air and the fuel; an inlet formed in the second end face for introducing the air; and a flow path surface connecting the inlet and the injection port, the flow path surface having at least one fuel injection port formed therein for injecting the fuel.

[0007] A gas turbine combustor according to at least one embodiment of the present disclosure includes: the combustion liner; a combustor that injects the fuel into the combustion liner; and the above-described two-stage combustion nozzle disposed downstream of the combustor in a gas flow direction of combustion gas in the combustion chamber.

[0008] According to the present disclosure, there is provided a two-stage combustion nozzle and a gas turbine combustor that are capable of suppressing abnormal combustion.

[0009] FIG. 1 is a schematic diagram of a gas turbine. FIG. 2 is a schematic diagram of a gas turbine combustor. FIG. 3 is a schematic cross-sectional view of a two-stage combustion nozzle according to a first embodiment. FIG. 4 is a schematic cross-sectional view of a nozzle flow path. FIG. 5 is a schematic diagram of an inlet. FIG. 6 is a schematic diagram of an injection port. FIG. 7 is a schematic cross-sectional view of a nozzle flow path (modification). FIG. 8 is a schematic cross-sectional view of a two-stage combustion nozzle according to a second embodiment. FIG. 9 is a schematic diagram of an inlet. FIG. 10 is a schematic diagram of an injection port.

[0010] Several embodiments of the present disclosure will be described below with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of components described as embodiments or shown in the drawings are not intended to limit the scope of the present disclosure and are merely illustrative examples. For example, expressions expressing relative or absolute arrangements, such as "in a certain direction," "along a certain direction," "parallel," "orthogonal," "center," "concentric," or "coaxial," not only strictly express such arrangements, but also express relative displacements with a tolerance or angle or distance to the extent that the same function is achieved. For example, expressions expressing the equality of things, such as "same," "equal," and "homogeneous," not only express strict equality, but also express tolerance or differences to the extent that the same function is achieved. For example, expressions expressing shapes such as a square or cylindrical shape not only express shapes such as a square or cylindrical shape in the strict geometric sense, but also express shapes including concave and convex portions, chamfered portions, etc., to the extent that the same effect is achieved. On the other hand, the expressions "comprise," "include," or "have" one component are not exclusive expressions that exclude the existence of other components. Note that similar components may be assigned the same reference numerals and descriptions thereof may be omitted.

[0011] <Overview of Gas Turbine 100> Fig. 1 is a schematic diagram showing a gas turbine 100 according to an embodiment of the present disclosure. The gas turbine 100 includes a compressor 2 for generating compressed air, a gas turbine combustor 4 for generating combustion gas using the compressed air and fuel, and a turbine 6 configured to be driven by the combustion gas discharged from the gas turbine combustor 4. In the gas turbine 100, which may be, for example, a single-shaft gas turbine, the compressor 2 and the turbine 6 are connected by a rotating shaft 9, and a generator 5 is further connected to this rotating shaft 9.

[0012] In the gas turbine combustor 4, a mixed gas containing compressed air delivered from the compressor 2 and fuel supplied from a fuel supply unit (not shown) is combusted to generate combustion gas as a working fluid that drives the turbine 6. The turbine 6 is driven by the combustion gas flowing into it, and the generator 5 generates electricity as a result of the rotation of the rotary shaft 9. Hereinafter, the compressed air delivered from the compressor 2 to the gas turbine combustor 4 may be simply referred to as "air."

[0013] The fuel supplied to the gas turbine combustor 4 may be natural gas, hydrogen gas, methane gas, light oil, heavy oil, jet fuel, gasified coal, or a combination of any two or more of these. In this example, natural gas and hydrogen gas are used as the fuel. That is, the gas turbine combustor 4 may burn only natural gas, a mixture of natural gas and hydrogen gas, or only hydrogen gas. The gas turbine combustor 4 according to other embodiments may use only hydrogen gas as the fuel.

[0014] 2 is a schematic diagram of a gas turbine combustor 4 according to an embodiment of the present disclosure. The gas turbine combustor 4 includes a combustion liner 40 that defines a combustion chamber 47, a combustor 8 provided at one end of the combustion liner 40, and a plurality of two-stage combustion nozzles 20 provided at a side wall 42 of the combustion liner 40.

[0015] The combustor 8 is configured to inject fuel and air along the axial direction of the combustion tube 40. An example of this configuration is disclosed in Japanese Patent Application Laid-Open No. 2013-096303. A detailed description will be omitted here, and only an outline will be provided below.

[0016] The combustor 8 includes a pilot burner disposed at the center of the combustion tube 40 and a plurality of main burners disposed at equal intervals around the pilot burner. The pilot burner has a pilot nozzle that supplies pilot fuel and a tubular member that is provided to surround the tip of the pilot nozzle. A pilot air passage is formed between the tubular member and the pilot nozzle, and air (pilot air) flows through the pilot air passage. The main burner includes a main nozzle that supplies main fuel and a main air passage that is formed around the main nozzle and supplies main air. The main fuel injected from the main nozzle is mixed with main air supplied through the main air passage to form a premixed gas.

[0017] The multiple two-stage combustion nozzles 20 are arranged on a side surface of a combustion liner 40. Each two-stage combustion nozzle 20 is located downstream of the combustor 8 in the gas flow direction, which is the flow direction of combustion gas within the combustion liner 40. The two-stage combustion nozzle 20 includes a nozzle body 30 and a flange portion 29. The flange portion 29 protrudes from the nozzle body 30 outward in the nozzle radial direction based on the nozzle axis C of the two-stage combustion nozzle 20. The nozzle body 30 is attached to the side wall 42 by joining the flange portion 29 to the side wall 42. By way of example only, the nozzle body 30 is manufactured by additive manufacturing, cutting, welding, or a combination thereof.

[0018] The nozzle body 30 includes a first end face 31, a second end face 32, and a plurality of nozzle flow paths 33. The first end face 31 is an end face of the nozzle body 30 on the inner circumferential side of the side wall 42 and faces the combustion chamber 47. The second end face 32 is an end face of the nozzle body 30 on the outer circumferential side of the side wall 42 and is located on the opposite side from the first end face 31. Each nozzle flow path 33 extends between the first end face 31 and the second end face 32 along the nozzle axis direction, which is the axial direction of the nozzle axis C. Although the example in FIG. 2 illustrates two nozzle flow paths 33, the present disclosure is not limited to this, and three or more nozzle flow paths 33 may be provided.

[0019] Each nozzle flow path 33 has an injection port 34 formed in the first end face 31, an inlet port 36 formed in the second end face 32, and a flow path surface 37 connecting the inlet port 36 and the injection port 34. The inlet port 36 is configured to introduce air into a flow path space Cs defined by the flow path surface 37. The inlet port 36 is formed in a bell-mouth shape, with the inner diameter of the inlet port 36 increasing toward the outer periphery of the side wall 42. At least one fuel injection port 38 is formed in the flow path surface 37 for injecting fuel into the flow path space Cs. Within the flow path space Cs, the air introduced through the inlet port 36 and the fuel injected from the fuel injection port 38 are mixed. The mixed fluid flows along the flow path surface 37 and is then injected from the injection port 34 into the combustion chamber 47.

[0020] The operation of the gas turbine combustor 4 is outlined as follows. The mixed gas obtained by mixing fuel and air injected from the combustor 8 is ignited, and a flame is generated inside the combustion chamber 47. The combustion gas generated in the combustion chamber 47 as a mainstream high-temperature gas flows downstream in the gas flow direction (to the right side of the page in the example of FIG. 2 ). The two-stage combustion nozzle 20 injects a mixed fluid containing fuel and air from the injection port 34 into the combustion chamber 47. The mixed fluid is ignited when mixed with the high-temperature combustion gas, and second-stage combustion occurs inside the combustion chamber 47.

[0021] The technical advantages of the two-stage combustion nozzle 20 will be summarized below. According to the above-described configuration, the number of nozzle flow paths 33 is multiple, allowing the flow path area of ​​each nozzle flow path 33 to be reduced. This allows fuel injected from the fuel injection port 38 to easily reach the center of the flow path space Cs, promoting the mixing of fuel and air within the nozzle flow path 33. Therefore, the flow path length of the nozzle flow path 33 required for sufficient mixing of fuel and air can be shortened, thereby suppressing the development of a low-flow-velocity region (wall boundary layer) of the mixed fluid on the flow path surface 37. Additionally, by reducing the flow path area of ​​each flow path, the fluid dynamic length scale is reduced, thereby reducing the absolute value of the thickness of the low-flow-velocity region (wall boundary layer). This suppresses abnormal flame holding, in which fuel in the low-flow-velocity region ignites and remains within the nozzle flow path 33, or flashback, in which a flame generated by fuel in the low-flow-velocity region flows backward. This achieves a two-stage combustion nozzle 20 capable of suppressing abnormal combustion. Furthermore, in this example, hydrogen fuel, which has high flammability, is used as the fuel, but even in this case, the above configuration can suppress abnormal combustion in the two-stage combustion nozzle.

[0022] Furthermore, since the inlet 36 has a bell-mouth shape, it is possible to prevent a flow velocity region (flow separation region) from occurring on the flow path surface 37 immediately downstream of the inlet 36, thereby further suppressing the abnormal flame stabilization described above.

[0023] Below, the details of the two-stage combustion nozzle 20 will be explained separately for the two-stage combustion nozzle 20A according to the first embodiment (FIGS. 3 to 7) and the two-stage combustion nozzle 20B according to the second embodiment (FIGS. 8 to 10).

[0024] First Embodiment A two-stage combustion nozzle 20A (20) according to a first embodiment will be described with reference to Figures 3 to 7. As shown in Figure 3, the nozzle body 30A (30) of the two-stage combustion nozzle 20A includes a first end face 31A (31), a second end face 32A (32), and a plurality of nozzle flow paths 33A (33). The second end face 32A is curved so as to be convex toward the outer periphery of the side wall 42 of the combustion liner 40. The number of nozzle flow paths 33A illustrated in Figure 3 is four.

[0025] 4 is a schematic cross-sectional view of each nozzle flow path 33 A. When viewed along the nozzle flow direction, which is the flow direction in the nozzle flow path 33 A (33), each nozzle flow path 33 A is formed in the shape of a slot having a longitudinal direction and a lateral direction, and more specifically, the nozzle flow path 33 A is a slot that extends linearly in the longitudinal direction.

[0026] Therefore, as shown in Figures 5 and 6, the inlet ports 36A and the jet ports 34A of the nozzle body 30A are also slots that extend linearly in the longitudinal direction. In this example, four inlet ports 36A are arranged at equal intervals on the second end face 32A along the lateral direction of the nozzle flow path 33A. The distance between two adjacent inlet ports 36A in the lateral direction corresponds to dimension L1 in Figure 5. Similarly, four jet ports 34A are arranged at equal intervals on the first end face 31A along the lateral direction. The distance between two adjacent jet ports 34A in the lateral direction corresponds to dimension L2 in Figure 6. In some embodiments, dimension L2 is shorter than dimension L1. The reason for this will be described later.

[0027] Arrow F in Figure 6 indicates the gas flow direction of the combustion gas in the combustion chamber 47. As can be seen from the figure, the longitudinal direction of each injection port 34A is aligned with the gas flow direction of the combustion gas in the combustion chamber 47. As a more specific example, the longitudinal direction and the gas flow direction are parallel to each other. As another more specific example, the longitudinal direction is inclined with respect to the gas flow direction. In this case, the acute angle between the gas flow direction and the longitudinal direction is greater than 0° and equal to or less than 45°.

[0028] As shown in Figures 3 and 5, the nozzle body 30A includes a plurality of fuel inlets 27, a plurality of fuel chambers 60, and a fuel injection port 38. The plurality of fuel inlets 27 are formed in a sidewall surface 28 of the nozzle body 30A. Fuel introduced through each fuel inlet 64 is supplied to one of the plurality of fuel chambers 60. The plurality of fuel chambers 60 are arranged alternately with the plurality of nozzle flow paths 33A along the short direction of the nozzle flow path 33A. The fuel injection port 38 is formed in a flow path surface 37A (37) of the nozzle flow path 33A and is configured to inject fuel stored in the fuel chambers 60 into the flow path space Cs.

[0029] 4 , the flow path surface 37A (37) includes an extension surface 43 extending in the longitudinal direction, and the extension surface 43 includes a first extension surface 431 and a second extension surface 432 that face each other in the lateral direction. The fuel injection port 38 has a plurality of first fuel injection ports 381 arranged on the first extension surface 431 and a plurality of second fuel injection ports 382 arranged on the second extension surface 432. Each of the first fuel injection ports 381 and each of the second fuel injection ports 382 are oriented along the lateral direction.

[0030] 4 , the multiple first fuel ejection ports 381 and the multiple second fuel ejection ports 382 face each other in the short-side direction. Specifically, the first fuel ejection ports 381 and the second fuel ejection ports 382, ​​which face each other, are arranged such that at least a portion of the area where the first fuel ejection ports 381 are formed in the short-side direction is included in the area where the second fuel ejection ports 382 are formed in the short-side direction, and more preferably, the two areas where the first fuel ejection ports 381 are formed coincide with each other in the short-side direction.

[0031] As shown in FIGS. 3 and 5, the nozzle body 30A includes a film air inlet 51, a film air chamber 52, and a film air outlet 55.

[0032] The film air inlet 51 is disposed on the second end surface 32A. In this example, the multiple film air inlet 51 are disposed radially outward of the four film air inlet 51 and along the circumferential direction of the nozzle based on the nozzle axis C. Each film air inlet 51 is a slot having a longitudinal direction and a lateral direction.

[0033] The film air chamber 52 is supplied with air introduced through the film air inlet 51. The film air chamber 52 has a first film air chamber 521 extending in the nozzle circumferential direction, a second film air chamber 522 extending in the nozzle circumferential direction and radially inward of the first film air chamber 521, and a third film air chamber 523 positioned radially inward of the second film air chamber 522.

[0034] In this example, the air introduced through each film air inlet 51 is supplied to the first film air chamber 521. Then, some of the air stored in the first film air chamber 521 is discharged and flows into the second film air chamber 522. Furthermore, some of the air stored in the second film air chamber 522 is discharged and flows into the third film air chamber 523 where it is stored.

[0035] The film air injection ports 55 are formed on the flow path surface 37A of each of the four nozzle flow paths 33A and are located closer to the injection port 34A than the fuel injection ports 38, more specifically, near the injection port 34A. The film air injection ports 55 inject the air stored in the film air chamber 52 as film air. In this example, the film air injection ports 55 are oriented downstream in the nozzle flow direction. In other words, the center line of the film air injection port 55 extends more downstream as it approaches the center line of the flow path space Cs. Therefore, the film air injected from the film air injection ports 55 can flow along the flow path surface 37A into the combustion chamber 47.

[0036] As shown in Figure 3, the four nozzle flow paths 33A include a pair of adjacent nozzle flow paths 35 adjacent to each other in the short direction. In this example, there are three pairs of adjacent nozzle flow paths 35, but for ease of viewing the drawing, only one of these pairs is indicated by the reference numeral "35." Any of the multiple fuel chambers 60 described above is disposed between the pair of adjacent nozzle flow paths 35. The fuel chamber 60 supplies fuel to each fuel injection port 38 of the pair of adjacent nozzle flow paths 35.

[0037] Each adjacent nozzle flow path 35 includes a first predetermined flow path 351 having a first predetermined length from the inlet 36A toward the downstream side in the nozzle flow direction. The first predetermined length corresponds to the dimension M1 in FIG. 3. The pair of first predetermined flow paths 351 extend along the nozzle axial direction so as to approach each other in the short side direction as they move toward the combustion chamber 47 in the nozzle axial direction. Therefore, the dimension L2 in FIG. 6 is shorter than the dimension L1 in FIG. 5.

[0038] The technical advantages of the two-stage combustion nozzle 20A according to the first embodiment will now be described. Generally, when realizing a predetermined total flow path cross-sectional area, employing multiple slot-shaped nozzle flow paths 33A allows for a smaller number of nozzle flow paths 33A than employing multiple circular nozzle flow paths 33A. In this regard, because the nozzle flow paths 33A (33) are formed as slots having longitudinal and lateral directions, the number of nozzle flow paths 33A can be reduced, thereby reducing the number of fuel chambers 60 for supplying fuel to each nozzle flow path 33A. This allows for a simplification of the two-stage combustion nozzle 20A (20). Furthermore, because the nozzle flow paths 33A are linearly extending slots, the processing required to manufacture the two-stage combustion nozzle 20A is simplified.

[0039] Furthermore, because the longitudinal direction of the injection port 34A is along the gas flow direction in the combustion chamber 47, the mixed fluid injected from the injection port 34A is long along the gas flow direction within the combustion chamber 47 and short in the circumferential direction of the side wall 42 of the combustion liner 40. Therefore, the area where the combustion gas collides with the mixed fluid injected into the combustion chamber 47 is small, and the mixed fluid can be prevented from flowing downstream in the gas flow direction together with the combustion gas. Therefore, the mixed fluid easily travels along the radial direction of the combustion liner 40 and can reach near the center of the combustion liner 40, achieving good two-stage combustion of the combustion gas.

[0040] Furthermore, according to the inventors' findings, because the flow velocity of air introduced through the inlet 36A is generally high, the fuel injected from the fuel injection port 38 tends to flow downstream in the nozzle flow direction and is unlikely to reach the center of the nozzle flow path 33A. However, because the flow path surface 37A includes the extension surface 43 and the fuel injection port 38 formed on the extension surface 43 is oriented along the short side, the fuel injected from the fuel injection port 38 can reach the center of the nozzle flow path 33A in the short side (the two-dot chain line N1 in FIG. 4 ). This further promotes mixing of the fuel and air.

[0041] Furthermore, the extension surface 43 includes a first extension surface 431 and a second extension surface 432 that face each other in the short side direction, and the first fuel injection ports 381 are formed on the first extension surface 431, and the second fuel injection ports 382 are formed on the second extension surface 432. According to the above configuration, each of the first fuel injection ports 381 and the second fuel injection ports 382 injects fuel. This makes it easier for the fuel to spread throughout the nozzle flow path 33A in the short side direction, further promoting the mixing of fuel and air.

[0042] Furthermore, with a configuration in which the plurality of first fuel injection ports 381 and the plurality of second fuel injection ports 382 face each other in the lateral direction, the plurality of fuel injection ports 38 are aligned in the longitudinal direction, making it easier for the fuel injected by the fuel injection ports 38 to spread longitudinally within the nozzle flow path 33A. Furthermore, since the first fuel injection port 381 and the second fuel injection port 382 face each other in the lateral direction, it is even easier for the fuel injected by the fuel injection port 38 to reach the center of the nozzle flow path 33A in the lateral direction.

[0043] Furthermore, film air injection ports 55 are formed on the flow path surface 37A, and film air injected from the film air injection ports 55 dilutes the mixed fluid on the nozzle flow path 33A surface, thereby lowering the fuel concentration. This makes it possible to suppress flashback within the nozzle flow path 33A. Furthermore, by orienting the film air injection ports 55 downstream in the nozzle flow direction, the film air is more likely to flow along the flow path surface 37A. This makes it possible to enhance the dilution effect of the mixed fluid.

[0044] Furthermore, the pair of first predetermined flow passages 351 extend along the nozzle axis direction so as to approach each other in the short direction toward the combustion chamber 47 in the nozzle axis direction. According to the above configuration, the distance between the pair of adjacent nozzle flow passages 35 (dimension L1 in FIG. 5 ) can be increased near the inlet 36A, thereby enlarging the fuel chamber 60 between the pair of adjacent nozzle flow passages 35. This increases the amount of fuel stored in the nozzle body 30A. Meanwhile, the distance between the pair of adjacent nozzle flow passages 35 can be reduced near the injection port 34A. The distance between the two injection ports 34A (dimension L2 in FIG. 6 ) can be reduced, thereby suppressing flame stabilization in the low-flow-velocity region on the first end face 31 between the two injection ports 34A. This suppresses flashback and achieves favorable two-stage combustion.

[0045] Furthermore, by configuring the second end surface 32A to be curved so as to be convex toward the outer periphery of the side wall 42 of the combustion liner 40, the flow path length of the adjacent nozzle flow paths 35 can be adjusted by adjusting the position of the inlet 36A in the second end surface 32A during the design stage of the two-stage combustion nozzle 20A. This makes it easy to make the flow path lengths of a pair of adjacent nozzle flow paths 35 approximately the same. Since the flow path lengths for mixing air and fuel can be made approximately the same among the multiple nozzle flow paths 33A, the fuel concentration of the mixed fluid injected from the injection port 34A can be made approximately the same among the multiple nozzle flow paths 33A. This makes it possible to achieve good two-stage combustion.

[0046] 7 is a schematic cross-sectional view of a nozzle flow path 33A (33) according to a modification of the first embodiment. The first fuel ejection ports 381 and the second fuel ejection ports 382 may be arranged alternately in the longitudinal direction. In other words, the formation area of ​​each first fuel ejection port 381 and the formation area of ​​each second fuel ejection port 382 may be separated from each other in the lateral direction.

[0047] According to the above configuration, the plurality of first fuel injection ports 381 and the plurality of second fuel injection ports 382 are formed on the first extension surface 431 and the second extension surface 432, respectively, so that fuel injected from the fuel injection ports 38 easily reaches the center of the nozzle flow path 33A in the lateral direction (the two-dot chain line N2 in FIG. 7 ), and the fuel easily spreads throughout the nozzle flow path 33A in the lateral direction. Furthermore, the plurality of first fuel injection ports 381 and the plurality of second fuel injection ports 382 are arranged alternately in the longitudinal direction, so that the fuel injected from the fuel injection ports 38 easily spreads throughout the nozzle flow path 33A in the longitudinal direction. This further promotes mixing of fuel and air.

[0048] In the first embodiment described above, the number of first fuel injection ports 381 arranged on the first extension surface 431 may be one. Similarly, the number of second fuel injection ports 382 arranged on the second extension surface 432 may be one. Alternatively, the two-stage combustion nozzle 20A may be provided with only either the first fuel injection port 381 or the second fuel injection port 382. The function of injecting film air is not an essential function of the two-stage combustion nozzle 20A. In other words, the film air injection port 55 does not have to be provided in the nozzle body 30A.

[0049] Second Embodiment A two-stage combustion nozzle 20B (20) according to a second embodiment will be described with reference to Figures 8 to 10. In the figures, the same components as those in the first embodiment are assigned the same reference numerals, and their description may be omitted or simplified below. Furthermore, in the nozzle body 30B (30) shown in Figures 9 and 10, the areas where spaces are formed are hatched to make it easier to distinguish between areas where spaces are not formed and areas where spaces are not formed.

[0050] As shown in FIG. 8 , the nozzle body 30B (30) of the two-stage combustion nozzle 20B includes a first end face 31B (31) and a second end face 32B (32). As shown in FIGS. 9 and 10 , the injection ports 34B (34) formed in the first end face 31B and the inlet ports 36B (36) formed in the second end face 32B both extend in the nozzle circumferential direction. That is, each of the multiple nozzle flow paths 33B (33) formed in the nozzle body 30B is formed as a slot having a longitudinal direction and a lateral direction. More specifically, each nozzle flow path 33B (33) is a curved slot whose longitudinal direction is the nozzle circumferential direction and whose lateral direction is the nozzle radial direction. Therefore, the flow path surface 37B (37) of the nozzle flow path 33B is a curved surface extending in the nozzle circumferential direction, and multiple fuel injection ports 38 (see FIG. 8 ) are arranged along the nozzle circumferential direction on each flow path surface 37B.

[0051] 9 , the plurality of nozzle flow paths 33B include inner curved nozzle flow paths 81 extending in the nozzle circumferential direction, and outer curved nozzle flow paths 83 extending in the nozzle circumferential direction radially outward of the inner curved nozzle flow paths 81. In this example, the two inner curved nozzle flow paths 81 are arranged side by side in the nozzle circumferential direction, and the two outer curved nozzle flow paths 83 are arranged side by side in the nozzle circumferential direction.

[0052] The nozzle body 30B includes a partition portion 68 arranged to separate two circumferentially adjacent inner curved nozzle flow paths 81, and an outer partition portion 67 arranged to separate two circumferentially adjacent outer curved nozzle flow paths 83. The formation area of ​​each inner curved nozzle flow path 81 in the circumferential direction of the nozzle and the formation area of ​​each outer curved nozzle flow path 83 in the circumferential direction of the nozzle coincide with each other.

[0053] 8, one of the two inner curved nozzle flow paths 81 and one of the two outer curved nozzle flow paths 83 are arranged on the left side of the paper with respect to the nozzle axis C. These inner curved nozzle flow path 81 and outer curved nozzle flow path 83 are adjacent to each other in the nozzle radial direction. Furthermore, the other inner curved nozzle flow path 81 and the other outer curved nozzle flow path 83 are arranged on the right side of the paper with respect to the nozzle axis C, and these two are also adjacent to each other in the nozzle radial direction.

[0054] The inner curved nozzle flow path 81 and the outer curved nozzle flow path 83, which are adjacent in the nozzle radial direction, each include a second predetermined flow path 352 having a second predetermined length from the inlet 36B toward the downstream side. The second predetermined length corresponds to the dimension M2. The two second predetermined flow paths 352 extend along the nozzle axial direction so as to approach each other in the short direction as they move toward the combustion chamber 47 in the nozzle axial direction.

[0055] 8 and 9 , the nozzle body 30B includes an inner fuel chamber 66, a curved fuel chamber 63, and an outer curved fuel chamber 69. The inner fuel chamber 66 is located radially inward of the two inner curved nozzle flow passages 81 and includes a fuel inlet 64 that opens toward the outer periphery of the side wall 42 of the combustion liner 40. The curved fuel chamber 63 is located radially between the inner curved nozzle flow passage 81 and the outer curved nozzle flow passage 83 and extends circumferentially. The outer curved fuel chamber 69 is located radially outward of the two outer curved nozzle flow passages 83 and extends circumferentially.

[0056] The inner fuel chamber 66 and the curved fuel chamber 63 communicate with each other via a fuel flow path 61 formed inside a partition 68, and the curved fuel chamber 63 and the outer curved fuel chamber 69 communicate with each other via an outer fuel flow path 62 formed inside an outer partition 67. Fuel is supplied to the inner fuel chamber 66 from a fuel inlet 64. A portion of the fuel stored in the inner fuel chamber 66 is discharged and flows into the curved fuel chamber 63 via the fuel flow path 61. A portion of the fuel stored in the curved fuel chamber 63 is discharged and flows into the outer curved fuel chamber 69 via the outer fuel flow path 62, where it is stored. A detailed description of the process by which fuel is supplied to the fuel injection ports 38 will be omitted; for example, the fuel stored in the curved fuel chamber 63 is supplied to the fuel injection ports 38 of the inner curved nozzle flow path 81 and the fuel injection ports 38 of the outer curved nozzle flow path 83.

[0057] The two-stage combustion nozzle 20B has film air injection ports 56 formed on the flow path surface 37B. Each film air injection port 56 extending in the nozzle circumferential direction is configured to inject, as film air, air introduced through a film air inlet 156 formed on the second end face 32B. The film air injection ports 56 preferably face downstream in the nozzle flow direction. The configuration of the air flow path from the film air inlet 156 to the film air injection ports 56 is based on the same basic principle as in the first embodiment, and therefore will not be described in detail.

[0058] The technical advantages of the two-stage combustion nozzle 20B are as follows: With the nozzle flow path 33B configured as a curved slot, the curved mixed fluid is injected from the injection port 34B into the combustion chamber 47, and the mixed fluid can be well mixed with the combustion gas.

[0059] Furthermore, when the multiple nozzle flow paths 33B include two inner curved nozzle flow paths 81 and two outer curved nozzle flow paths 83, the mixed fluid injected from the outer curved nozzle flow paths 83 into the combustion chamber 47 functions as a shield to cover the mixed fluid injected from the injection ports 34B of the inner curved nozzle flow paths 81. This prevents the mixed fluid on the inner side in the nozzle radial direction from flowing in the gas flow direction together with the combustion gas. The mixed fluid easily travels along the radial direction of the combustion tube 40 and can reach near the center of the combustion tube 40, thereby achieving good two-stage combustion of the combustion gas. The number of inner curved nozzle flow paths 81 may be one or three or more. Similarly, the number of outer curved nozzle flow paths 83 may be one or three or more. Even in this case, the above-described technical advantages are still obtained.

[0060] Furthermore, by configuring the inner curved nozzle flow passage 81 and the outer curved nozzle flow passage 83 to each include the second predetermined flow passage 352, the distance between the pair of second predetermined flow passages 352 can be increased near the inlet 36B, thereby increasing the size of the inner fuel chamber 66 and the curved fuel chamber 63. This increases the amount of fuel stored in the nozzle body 30B. On the other hand, the distance between the pair of second predetermined flow passages 352 can be reduced near the injection nozzle 34B. The reduced distance between the two injection nozzles 34B suppresses flame stabilization in the low flow velocity region of the first end face 31 between the two injection nozzles 34B. This suppresses flashback and achieves good two-stage combustion.

[0061] Furthermore, by configuring the nozzle body 30B to include the curved fuel chamber 63, the curved fuel chamber 63 is shared between the inner curved nozzle flow passage 81 and the outer curved nozzle flow passage 83, thereby simplifying the two-stage combustion nozzle 20B.

[0062] Furthermore, with the configuration in which fuel flow passage 61 is formed inside partition 68, fuel supplied to inner fuel chamber 66 is supplied to curved fuel chamber 63 via fuel flow passage 61. Since there is no need to provide curved fuel chamber 63 with fuel inlet 64 that opens toward the outer periphery of side wall 42 of combustion liner 40, two-stage combustion nozzle 20B can be simplified.

[0063] <Summary> The contents described in the above-described embodiments can be understood, for example, as follows.

[0064] 1) A two-stage combustion nozzle (20) according to at least one embodiment of the present disclosure is a two-stage combustion nozzle configured to inject air and fuel into a combustion chamber (47) defined by a combustion liner (40) of a gas turbine (6), and includes a nozzle body (30) attached to a side wall (42) of the combustion liner, wherein the nozzle body includes: a first end face (31) that is an end face disposed on the inner periphery of the side wall and faces the combustion chamber; a second end face (32) opposite to the first end face; and a plurality of nozzle flow paths (33) each extending between the first end face and the second end face, wherein each of the plurality of nozzle flow paths has: an injection port (34) formed in the first end face for injecting the air and the fuel; an inlet (36) formed in the second end face for introducing the air; and a flow path surface (37) that connects the inlet and the injection port, and in which at least one fuel injection port (38) for injecting the fuel is formed.

[0065] According to the configuration of 1) above, since there are multiple nozzle flow paths, the flow path area of ​​each nozzle flow path can be reduced. This makes it easier for fuel injected from the fuel injection port to reach the center of the nozzle flow path, promoting mixing of fuel and air within the nozzle flow path. Therefore, the flow path length of the nozzle flow path required to sufficiently mix fuel and air can be shortened, thereby suppressing the development of a low-flow-velocity region (wall boundary layer) of the mixed fluid on the flow path surface. Additionally, the reduction in the flow path area of ​​each flow path also reduces the fluid dynamic length scale, contributing to the suppression of the development of the low-flow-velocity region (wall boundary layer). Therefore, abnormal flame holding, in which fuel in a low-flow-velocity region ignites and remains within the nozzle flow path, or flashback, in which a flame generated by fuel in a low-flow-velocity region flows backward, can be suppressed. This achieves a two-stage combustion nozzle that can suppress abnormal combustion.

[0066] 2) In some embodiments, in the two-stage combustion nozzle described in 1) above, each of the plurality of nozzle flow paths is formed in a slot shape having a longitudinal direction and a lateral direction when viewed along the flow direction in the nozzle flow path (nozzle flow direction).

[0067] Generally, to achieve a predetermined total flow passage cross-sectional area, the number of nozzle passages can be reduced by employing multiple slot-shaped nozzle passages compared to employing multiple circular nozzle passages. In this regard, the configuration of 2) above allows for a reduction in the number of nozzle passages, which in turn reduces the number of fuel chambers required to supply fuel to each nozzle passage. This allows for a simplification of the two-stage combustion nozzle.

[0068] 3) In some embodiments, in the two-stage combustion nozzle described in 2) above, the flow path surface includes an extension surface (43) extending in the longitudinal direction, and each of the at least one fuel injection port is formed on the extension surface and oriented along the short direction.

[0069] According to the inventor's findings, the flow velocity of air introduced through an inlet is generally high, making it difficult for fuel injected from the fuel injection port to reach the center of the nozzle flow channel. In this regard, with the configuration of 3) above, the fuel injection port is oriented along the short side direction, so that the fuel injected from the fuel injection port can reach the center of the nozzle flow channel in the short side direction. This further promotes mixing of fuel and air.

[0070] 4) In some embodiments, in the two-stage combustion nozzle described in 3) above, the extension surface has a first extension surface (431) and a second extension surface (432) that face each other in the short direction, and the at least one fuel injection port is a plurality of fuel injection ports having at least one first fuel injection port (381) arranged on the first extension surface, and at least one second fuel injection port (382) arranged on the second extension surface.

[0071] According to the configuration of 4) above, the first fuel injection port and the second fuel injection port formed on the first extension surface and the second extension surface, respectively, inject fuel, which makes it easier for the fuel to spread across the nozzle flow path in the short direction, and further promotes mixing of the fuel and air.

[0072] 5) In some embodiments, in the two-stage combustion nozzle described in 4) above, the at least one first fuel injection port is a plurality of the first fuel injection ports, the at least one second fuel injection port is a plurality of the second fuel injection ports, and the plurality of first fuel injection ports and the plurality of second fuel injection ports are opposed to each other in the short direction.

[0073] According to the configuration of 5) above, since the plurality of first fuel injection ports and the plurality of second fuel injection ports are aligned in the longitudinal direction, the fuel injected by the fuel injection ports is more likely to spread throughout the nozzle flow channel in the longitudinal direction. Furthermore, since the first fuel injection port and the second fuel injection port face each other in the lateral direction, the fuel injected from the fuel injection port is more likely to reach the center of the nozzle flow channel in the lateral direction.

[0074] 6) In some embodiments, in the two-stage combustion nozzle described in 4) above, the at least one first fuel injection port is a plurality of the first fuel injection ports, the at least one second fuel injection port is a plurality of the second fuel injection ports, and the plurality of first fuel injection ports and the plurality of second fuel injection ports are arranged alternately in the longitudinal direction.

[0075] According to the configuration of 6) above, the fuel injected from the fuel injection port is more likely to spread longitudinally within the nozzle flow channel, thereby further promoting the mixing of fuel and air.

[0076] 7) In some embodiments, in the two-stage combustion nozzle described in any one of 2) to 6) above, the flow path surface of each of the plurality of nozzle flow paths is formed with a film air injection port (55, 56) extending in the longitudinal direction, the film air injection port being for injecting film air on the injection port side of the at least one fuel injection port.

[0077] According to the configuration of 7) above, the film air injected from the film air injection port can dilute the mixed fluid on the nozzle flow path surface to lower the fuel concentration, thereby suppressing flashback in the nozzle flow path.

[0078] 8) In some embodiments, the two-stage combustion nozzle described in 7) above, wherein the film air injection port is directed downstream in the flow direction of the nozzle flow path.

[0079] According to the above configuration 8), the film air can easily flow along the flow path surface, thereby enhancing the effect of diluting the mixed fluid.

[0080] 9) In some embodiments, the two-stage combustion nozzle according to any one of 2) to 8) above, wherein each of the plurality of nozzle flow paths is a slot extending linearly in the longitudinal direction.

[0081] According to the configuration of 9) above, since the slots extend linearly, the machining for manufacturing the two-stage combustion nozzle becomes easier.

[0082] 10) In some embodiments, in the two-stage combustion nozzle described in 9) above, the plurality of nozzle flow paths are aligned in the short direction, and the longitudinal direction of each of the plurality of injection ports of the plurality of nozzle flow paths is a direction along the gas flow direction (arrow F) of the combustion gas in the combustion chamber.

[0083] According to the configuration of 10) above, the mixed fluid injected from the injection port is long in the gas flow direction within the combustion chamber and short in the circumferential direction of the side wall of the combustion liner. Therefore, the area where the combustion gas collides with the mixed fluid injected into the combustion chamber is small, and the mixed fluid is prevented from flowing downstream in the gas flow direction together with the combustion gas. This allows the mixed fluid to reach near the center of the combustion liner, achieving good two-stage combustion of the combustion gas.

[0084] 11) In some embodiments, in the two-stage combustion nozzle described in 9) or 10) above, the plurality of nozzle flow paths include a pair of adjacent nozzle flow paths (33) adjacent to each other in the short side direction, the nozzle body further includes a fuel chamber (60) for storing the fuel between the pair of adjacent nozzle flow paths and for supplying the fuel to the fuel injection ports of each of the pair of adjacent nozzle flow paths, each of the pair of adjacent nozzle flow paths includes a first predetermined flow path (351) having a first predetermined length (dimension M1) from the inlet toward the downstream side, and the pair of first predetermined flow paths extend along the nozzle axial direction of the two-stage combustion nozzle so as to approach each other in the short side direction the closer they are to the combustion chamber in the nozzle axial direction.

[0085] According to the configuration of 11) above, the distance between a pair of adjacent nozzle flow paths can be increased near the inlet, thereby enlarging the fuel chamber. This allows for an increased amount of fuel to be stored in the nozzle body. On the other hand, the distance between a pair of adjacent nozzle flow paths can be reduced near the injection ports. Because the distance between the two injection ports can be reduced, flame stabilization due to a low flow velocity region on the first end face between the mixed fluid injected from the two injection ports can be suppressed. This makes it possible to suppress flashback and achieve good two-stage combustion.

[0086] 12) In some embodiments, in the two-stage combustion nozzle described in 11) above, the second end surface of the nozzle body is curved so as to be convex toward the outer periphery of the side wall.

[0087] According to the configuration of 12) above, by adjusting the position of the inlet on the second end face during the design stage of the two-stage combustion nozzle, it is possible to make the flow path lengths of a pair of adjacent nozzle flow paths approximately the same. This makes it possible to make the flow path lengths for mixing air and fuel approximately the same among the multiple nozzle flow paths. Since the fuel concentration of the mixed fluid injected from the injection port can be made approximately the same among the multiple nozzle flow paths, good two-stage combustion can be achieved.

[0088] 13) In some embodiments, in the two-stage combustion nozzle described in any one of 2) to 8) above, each of the plurality of nozzle flow paths is a curved slot whose longitudinal direction is the nozzle circumferential direction of the two-stage combustion nozzle and whose lateral direction is the nozzle radial direction of the two-stage combustion nozzle.

[0089] According to the configuration of 13) above, the curved mixed fluid is injected from the injection port into the combustion chamber, and the mixed fluid can be mixed well with the combustion gas.

[0090] 14) In some embodiments, in the two-stage combustion nozzle described in 13) above, the plurality of nozzle flow paths include at least one inner curved nozzle flow path (81) extending in the nozzle circumferential direction, and at least one outer curved nozzle flow path (83) extending in the nozzle circumferential direction and outside the at least one inner curved nozzle in the nozzle radial direction.

[0091] According to the configuration of 14) above, the mixed fluid injected from the outer curved nozzle channel into the combustion chamber functions as a shield to cover the mixed fluid injected from the injection port of the inner curved channel. This prevents the inner mixed fluid from flowing in the gas flow direction together with the combustion gas. The mixed fluid can reach near the center of the combustion liner, thereby achieving good two-stage combustion of the combustion gas.

[0092] 15) In some embodiments, in the two-stage combustion nozzle described in 14) above, the inner curved nozzle flow path and the outer curved nozzle flow path each include a second predetermined flow path (352) having a second predetermined length (dimension M2) from the inlet toward the downstream side, and the two second predetermined flow paths extend along the nozzle axial direction of the two-stage combustion nozzle so as to approach each other in the short direction as they move toward the combustion chamber in the nozzle axial direction.

[0093] The configuration 15) above provides the same technical advantages as the configuration 11).

[0094] 16) In some embodiments, the two-stage combustion nozzle is described in 14) or 15) above, wherein the nozzle body further includes a curved fuel chamber (63) extending circumferentially around the nozzle between the inner curved nozzle flow passage and the outer curved nozzle flow passage, and the curved fuel chamber is configured to supply the fuel to the fuel injection ports of the inner curved nozzle flow passage and the fuel injection ports of the outer curved nozzle flow passage.

[0095] According to the configuration of 16) above, the curved fuel chamber is shared between the inner curved nozzle flow passage and the outer curved nozzle flow passage, thereby simplifying the two-stage combustion nozzle.

[0096] 17) In some embodiments, in the two-stage combustion nozzle described in 16) above, the at least one inner curved nozzle flow path is a plurality of the inner curved nozzle flow paths lined up in the nozzle circumferential direction, and the nozzle body includes: an inner fuel chamber (66) for storing the fuel inside the plurality of inner curved nozzle flow paths in the nozzle radial direction, the inner fuel chamber including a fuel inlet (27) that opens toward the outer periphery of the side wall; and a partition section (68) arranged to separate two of the plurality of inner curved nozzle flow paths that are adjacent in the nozzle circumferential direction, and a fuel flow path (61) is formed inside the partition section for guiding the fuel in the inner fuel chamber to the curved fuel chamber.

[0097] According to the configuration of 17), the fuel supplied to the inner fuel chamber is supplied to the curved fuel chamber via the fuel flow path, and since there is no need to provide a fuel inlet opening toward the outer periphery of the side wall of the combustion liner in the curved fuel chamber, the two-stage combustion nozzle can be simplified.

[0098] 18) In some embodiments, in the two-stage combustion nozzle according to any one of 1) to 17) above, the inlet is formed in a bell-mouth shape in which the inner diameter of the inlet increases toward the outer periphery of the side wall.

[0099] According to the configuration of 18) above, it is possible to suppress the occurrence of a low flow velocity region (separation region) on the flow path surface immediately downstream of the inlet, which leads to the prevention of abnormal combustion caused by fuel stagnation in the low flow velocity region.

[0100] 19) In some embodiments, the two-stage combustion nozzle according to any one of 1) to 18) above, wherein the fuel comprises hydrogen fuel.

[0101] According to the configuration of 19) above, even when highly flammable hydrogen fuel is used, abnormal combustion in the two-stage combustion nozzle can be suppressed.

[0102] 20) A gas turbine combustor (4) according to at least one embodiment of the present disclosure comprises: the combustion liner; a combustor (8) for injecting the fuel into the combustion liner; and the two-stage combustion nozzle (20) according to any one of 1) to 19) above, which is disposed downstream of the combustor in a gas flow direction of combustion gas in the combustion chamber.

[0103] According to the configuration 20) above, the same technical advantages as those of the configuration 1) above can be obtained.

[0104] DESCRIPTION OF SYMBOLS 2: Compressor 4: Gas turbine combustor 5: Generator 6: Turbine 8: Combustor 9: Rotating shaft 27: Fuel inlet 28: Side wall surface 29: Flange portion 30A, 30B (30): Nozzle body 31A, 31B (31): First end face 32A, 32B (32): Second end face 33A, 33B (33): Nozzle flow path 34A, 34B (34): Injection port 35: Adjacent nozzle flow path 36A, 36B (36): Inlet 37A, 37B (37): Flow path surface 38: Fuel injection port 40: Combustion liner 42: Side wall 43: Extension surface 47: Combustion chamber 51: Film air inlet 52: Film air chamber 55 : Film air jet orifice 56 : Film air jet orifice 60 : Fuel chamber 61 : Fuel flow path 62 : Outer fuel flow path 63 : Curved fuel chamber 64 : Fuel inlet 66 : Inner fuel chamber 67 : Outer partition 68 : Partition 69 : Outer curved fuel chamber 81 : Inner curved nozzle flow path 83 : Outer curved nozzle flow path 100 : Gas turbine 156 : Film air inlet 351 : First predetermined flow path 352 : Second predetermined flow path 381 : First fuel jet orifice 382 : Second fuel jet orifice 431 : First extension surface 432 : Second extension surface 521 : First film air chamber 522 : Second film air chamber 523 : Third film air chamber C : Nozzle axis Cs : Flow path space F : Arrow L1, L2, M1, M2: Dimensions N1, N2: Two-dot chain lines

Claims

1. A two-stage combustion nozzle configured to inject air and fuel into a combustion chamber defined by a combustion liner of a gas turbine, comprising a nozzle body attached to a side wall of the combustion liner, the nozzle body including: a first end face that is an end face located on the inner periphery of the side wall and faces the combustion chamber; a second end face opposite to the first end face; and a plurality of nozzle flow paths each extending between the first end face and the second end face, each of the plurality of nozzle flow paths having: an injection port formed in the first end face for injecting the air and the fuel; an inlet formed in the second end face for introducing the air; and a flow path surface connecting the inlet and the injection port, the flow path surface having at least one fuel injection port for injecting the fuel formed therein.

2. A two-stage combustion nozzle as set forth in claim 1, wherein each of the plurality of nozzle flow paths is formed in a slot shape having a longitudinal direction and a lateral direction when viewed along the flow direction in the nozzle flow path.

3. A two-stage combustion nozzle as set forth in claim 2, wherein the flow path surface includes an extension surface extending in the longitudinal direction, and each of the at least one fuel injection port is formed on the extension surface and directed along the short direction.

4. The two-stage combustion nozzle according to claim 3, wherein the extension surface has a first extension surface and a second extension surface that face each other in the short direction, and the at least one fuel injection port is a plurality of fuel injection ports including at least one first fuel injection port arranged on the first extension surface and at least one second fuel injection port arranged on the second extension surface.

5. The two-stage combustion nozzle according to claim 4, wherein the at least one first fuel injection port is a plurality of the first fuel injection ports, the at least one second fuel injection port is a plurality of the second fuel injection ports, and the plurality of first fuel injection ports and the plurality of second fuel injection ports are opposed to each other in the short side direction.

6. The two-stage combustion nozzle according to claim 4, wherein the at least one first fuel injection port is a plurality of the first fuel injection ports, the at least one second fuel injection port is a plurality of the second fuel injection ports, and the plurality of first fuel injection ports and the plurality of second fuel injection ports are arranged alternately in the longitudinal direction.

7. A two-stage combustion nozzle as set forth in any one of claims 2 to 6, wherein the flow path surface of each of the plurality of nozzle flow paths is formed with a film air injection port extending in the longitudinal direction, the film air injection port being for injecting film air on the injection port side of the at least one fuel injection port.

8. A two-stage combustion nozzle according to claim 7, wherein the film air injection port is directed downstream in the flow direction of the nozzle flow path.

9. A two-stage combustion nozzle according to any one of claims 2 to 4, wherein each of the plurality of nozzle flow passages is a slot extending linearly in the longitudinal direction.

10. A two-stage combustion nozzle as set forth in claim 9, wherein the plurality of nozzle flow paths are aligned in the short direction, and the longitudinal direction of each of the plurality of injection ports of the plurality of nozzle flow paths is a direction along the gas flow direction of combustion gas in the combustion chamber.

11. A two-stage combustion nozzle as set forth in claim 9, wherein the plurality of nozzle flow paths include a pair of adjacent nozzle flow paths adjacent to each other in the short-side direction, the nozzle body further includes a fuel chamber for storing the fuel between the pair of adjacent nozzle flow paths and for supplying the fuel to the fuel injection ports of each of the pair of adjacent nozzle flow paths, each of the pair of adjacent nozzle flow paths includes a first predetermined flow path having a first predetermined length downstream from the inlet, and the pair of first predetermined flow paths extend along the nozzle axial direction of the two-stage combustion nozzle so as to approach each other in the short-side direction the closer they are to the combustion chamber in the nozzle axial direction.

12. A two-stage combustion nozzle as set forth in claim 11, wherein the second end surface of the nozzle body is curved so as to be convex toward the outer periphery of the side wall.

13. A two-stage combustion nozzle as set forth in any one of claims 2 to 4, wherein each of the plurality of nozzle flow paths is a curved slot whose longitudinal direction is the nozzle circumferential direction of the two-stage combustion nozzle and whose lateral direction is the nozzle radial direction of the two-stage combustion nozzle.

14. A two-stage combustion nozzle as set forth in claim 13, wherein the plurality of nozzle flow paths include: at least one inner curved nozzle flow path extending in the nozzle circumferential direction; and at least one outer curved nozzle flow path extending in the nozzle circumferential direction and located outside the at least one inner curved nozzle in the nozzle radial direction.

15. A two-stage combustion nozzle as set forth in claim 14, wherein the inner curved nozzle flow path and the outer curved nozzle flow path each include a second predetermined flow path having a second predetermined length from the inlet toward the downstream side, and the two second predetermined flow paths extend along the nozzle axial direction of the two-stage combustion nozzle so as to approach each other in the short side direction the closer they are to the combustion chamber in the nozzle axial direction.

16. A two-stage combustion nozzle as described in claim 14, wherein the nozzle body further includes a curved fuel chamber extending circumferentially around the nozzle between the inner curved nozzle passage and the outer curved nozzle passage, and the curved fuel chamber is configured to supply the fuel to the fuel injection ports of the inner curved nozzle passage and the fuel injection ports of the outer curved nozzle passage.

17. A two-stage combustion nozzle as set forth in claim 16, wherein the at least one inner curved nozzle flow passage comprises a plurality of the inner curved nozzle flow passages aligned in the nozzle circumferential direction, and the nozzle body comprises: an inner fuel chamber for storing the fuel inside the plurality of inner curved nozzle flow passages in the nozzle radial direction, the inner fuel chamber including a fuel inlet opening toward the outer periphery of the side wall; and a partition section arranged to separate two of the plurality of inner curved nozzle flow passages adjacent to each other in the nozzle circumferential direction, and a fuel flow passage formed inside the partition section for guiding the fuel in the inner fuel chamber to the curved fuel chamber.

18. A two-stage combustion nozzle as set forth in any one of claims 1 to 6, wherein the inlet is formed in a bell-mouth shape such that the inner diameter of the inlet increases toward the outer periphery of the side wall.

19. A two-stage combustion nozzle as claimed in any one of claims 1 to 6, wherein the fuel comprises hydrogen fuel.

20. A gas turbine combustor comprising: the combustion liner; a combustor for injecting the fuel into the combustion liner; and the two-stage combustion nozzle according to any one of claims 1 to 6, which is disposed downstream of the combustor in the gas flow direction of combustion gas in the combustion chamber.

Images