Backflow-type combustor for gas turbine

Abstract

This backflow-type combustor for a gas turbine comprises: an annular outer liner; an annular inner liner; an annular end liner that is disposed on one side in an axial direction with respect to the outer liner and the inner liner and that connects the outer liner to the inner liner; a combustion chamber that is delimited by the outer liner, the inner liner, and the end liner; and a baffle that is partially disposed in the combustion chamber in a circumferential direction, where the baffle links the outer liner to the inner liner so as to cross the combustion chamber while being separated from the end liner in the axial direction.

Description

Reverse-flow combustor for a gas turbine

[0001] The present disclosure relates to a reverse-flow combustor for a gas turbine.

[0002] Patent Document 1 discloses a reverse-flow combustor for a gas turbine. Compressed air is supplied to the combustor from a compressor, and fuel is supplied from a fuel injector. In the combustor, fuel and compressed air are mixed and burned, and the combustion gas generated in the combustor is supplied to the turbine to drive the turbine.

[0003] US4549402B

[0004] Depending on the situation of the combustor, the flame in the combustion chamber may be difficult to maintain stably. If the flame in the combustion chamber is not stable, the output of the gas turbine will also become unstable. In addition, since the combustor can vibrate due to the influence of combustion or the like, it is also desirable to improve the vibration resistance performance of the combustor.

[0005] Therefore, one aspect of the present disclosure aims to improve the flame retention performance and vibration resistance performance of a reverse-flow combustor for a gas turbine.

[0006] A reverse-flow combustor for a gas turbine according to one aspect of the present disclosure is a reverse-flow combustor for a gas turbine provided with a rotating shaft having an axis extending in the axial direction, including an annular outer liner extending in the circumferential direction around the axis, an annular inner liner facing the outer liner from the inner side in the radial direction orthogonal to the axis, an annular end liner disposed on one side in the axial direction with respect to the outer liner and the inner liner and connecting the outer liner to the inner liner, a combustion chamber defined by the outer liner, the inner liner, and the end liner, and a baffle partially disposed in the combustion chamber in the circumferential direction, the baffle connecting the outer liner to the inner liner so as to cross the combustion chamber in a state spaced apart from the end liner in the axial direction.

[0007] According to one aspect of the present disclosure, the flame retention performance and vibration resistance performance of a reverse-flow combustor for a gas turbine can be improved.

[0008] Figure 1 is a cross-sectional view of a gas turbine according to an embodiment. Figure 2 is a cross-sectional view taken along line II-II in Figure 4. Figure 3 is a cross-sectional view taken along line III-III in Figure 4. Figure 4 is a view of a part of the outer liner of the combustor in Figure 1, seen from the radially outer side. Figure 5 is a cross-sectional view taken along line V-V in Figure 2.

[0009] Embodiments will be described below with reference to the drawings. In the following description, the direction in which the axis X of the rotating shaft 2 of the gas turbine 1 extends will be referred to as the axial direction X. The axis X of the rotating shaft 2 coincides with the axis X of the combustor 5. Front and front side mean the upstream side in the direction in which air flows through the compressor 4 and turbine 6 of the gas turbine 1, and rear and rear side mean the downstream side in the direction in which air flows through the compressor 4 and turbine 6 of the gas turbine 1. That is, front and front side mean the side on which the fan 3 is located in the axial direction X of the gas turbine 1, and rear and rear side mean the side opposite to the side on which the fan 3 is located in the axial direction X of the gas turbine 1. Radial direction R means the direction perpendicular to the axis X. Circumferential direction C means the direction around the axis X. Since the combustor 5 is a backflow type, the upstream side of the combustor 5 means the downstream side of the compressor 4 and turbine 6, and the downstream side of the combustor 5 means the upstream side of the compressor 4 and turbine 6.

[0010] Figure 1 is a cross-sectional view of a gas turbine 1 according to an embodiment. The gas turbine 1 is used, for example, as an engine for an aircraft. As shown in Figure 1, the gas turbine 1 comprises a rotating shaft 2, a fan 3, a compressor 4, a combustor 5, a turbine 6, and a casing 7. The rotating shaft 2 extends in the front-rear direction of the gas turbine 1. The fan 3 is connected to the front of the rotating shaft 2 and rotates together with the rotating shaft 2. The compressor 4, combustor 5, and turbine 6 are arranged in this order from front to rear along the rotating shaft 2. The casing 7 is a cylindrical object having an axis that coincides with the axis X of the rotating shaft 2, and houses the rotating shaft 2, fan 3, compressor 4, combustor 5, and turbine 6.

[0011] The gas turbine 1 is, for example, a twin-shaft gas turbine. The rotating shaft 2 includes a low-pressure shaft 12 and a high-pressure shaft 11 which is arranged on the same axis as the low-pressure shaft 12 and is rotatable relative to the low-pressure shaft 12. The high-pressure shaft 11 is a tubular hollow shaft. The low-pressure shaft 12 is inserted through the hollow space of the high-pressure shaft 11. The low-pressure shaft 12 is longer than the high-pressure shaft 11 in the front-rear direction, and the front and rear parts of the low-pressure shaft 12 are exposed to the outside of the high-pressure shaft 11. The low-pressure shaft 12 is connected to a fan 3.

[0012] The compressor 4 includes a low-pressure compressor 13 and a high-pressure compressor 14 located behind the low-pressure compressor 13. The low-pressure compressor 13 is an axial-flow compressor, and the high-pressure compressor 14 is a centrifugal compressor. A diffuser 8 is located on the outer circumference of the high-pressure compressor 14 to send the air flowing out of the high-pressure compressor 14 to the rear. Behind the diffuser 8 is an annular combustor 5 having a ring shape extending in the circumferential direction C around the axis X. The combustor 5 is a back-flow combustor. Details of the combustor 5 will be described later, so the combustor 5 is shown schematically in Figure 1. The turbine 6 includes a high-pressure turbine 15 and a low-pressure turbine 16 located behind the high-pressure turbine 15. The low-pressure shaft 12 mechanically connects the low-pressure compressor 13 to the low-pressure turbine 16. The high-pressure shaft 11 mechanically connects the high-pressure compressor 14 to the high-pressure turbine 15.

[0013] The casing 7 includes a cylindrical inner shell 17 and an outer shell 18 arranged concentrically with respect to each other. The inner shell 17 houses the compressor 4, the combustor 5, and the turbine 6. A cylindrical bypass passage B is formed between the inner shell 17 and the outer shell 18. A portion of the air drawn in by the fan 3 flows through the bypass passage B and is discharged to the rear. The remaining air drawn in by the fan 3 flows into the low-pressure compressor 13. The air that has passed through the low-pressure compressor 13 and the high-pressure compressor 14 flows into the combustor 5 via the diffuser 8. The combustion gas discharged from the outlet of the combustor 5 flows into the high-pressure turbine 15 through the nozzle unit 9.

[0014] Figure 2 is a cross-sectional view taken along line II-II in Figure 4. As shown in Figure 2, one side of the combustor 5 in the axial direction X is the upstream side of the combustor 5 and the rear side of the gas turbine 1. The other side of the combustor 5 in the axial direction X is the downstream side of the combustor 5 and the front side of the gas turbine 1. The combustor 5 is a back-flow type combustor. The combustor 5 may be manufactured by processing a metal plate, or by additive manufacturing by stacking metal materials.

[0015] The combustor 5 comprises an outer liner 21, an inner liner 22, an end liner 23, an outer turn guide 24, and an inner turn guide 25. The outer liner 21 has an annular shape extending in the circumferential direction C around the axis X. The inner liner 22 has an annular shape with a smaller diameter than the outer liner 21. The inner liner 22 is arranged concentrically with the outer liner 21 and faces the outer liner 21 from the inside in the radial direction R perpendicular to the axis X. The outer liner 21 and the inner liner 22 are each cylindrical in shape extending in the axial direction X.

[0016] The end liner 23 is positioned on one side in the axial direction X relative to the outer liner 21 and the inner liner 22. The end liner 23 connects the outer liner 21 to the inner liner 22. The end liner 23 has an annular shape extending in the radial direction R. In a cross-sectional view from the circumferential direction C, the end liner 23 has a dome-shaped cross-section that is convex toward one side in the axial direction X. The outer liner 21, the inner liner 22, and the end liner 23 constitute the liner body 20.

[0017] The outer liner 21, inner liner 22, and end liner 23 define the combustion chamber S. That is, the combustion chamber S has an annular shape extending in the circumferential direction C around the axis X. The outer liner 21 and inner liner 22 extend from the end liner 23 to the other side in the axial direction X. The outer turn guide 24 curves from the tip of the outer liner 21 on the other side in the axial direction X, making a 180° change of direction, and extends to one side in the axial direction X. The inner turn guide 25 curves from the tip of the inner liner 22 on the other side in the axial direction X, making a 180° change of direction, and extends to one side in the axial direction X.

[0018] The outer turn guide 24 and the inner turn guide 25 define an exhaust passage T that is continuous with the combustion chamber S. Combustion gas generated in the combustor 5 flows from the combustion chamber S into the exhaust passage T. An outlet Ta of the exhaust passage T is located at the tip of the outer turn guide 24 and the inner turn guide 25 on one side in the axial direction X.

[0019] The exhaust port Ta of the combustor 5 faces a nozzle unit 9 (see Figure 1) which has multiple nozzle guide vanes. The combustion gas discharged from the exhaust port Ta of the combustor 5 is guided by the nozzle guide vanes of the nozzle unit 9 and flows into the high-pressure turbine 15.

[0020] The combustor 5 includes a casing structure 40 that covers the liner body 20 from the outside. The casing structure 40 includes an outer wall 41, an inner wall 42, and an end wall 43. The outer wall 41 is positioned outside the outer liner 21 in the radial direction R, with a gap between it and the outer liner 21. The gap between the outer liner 21 and the outer wall 41 is an air passage 51 through which air supplied from the diffuser 8 flows. The inner wall 42 is positioned inside the inner liner 22 in the radial direction R, with a gap between it and the inner liner 22. The gap between the inner liner 22 and the inner wall 42 is an air passage 52.

[0021] The end wall 43 is positioned on one side of the end liner 23 in the axial direction X, with a gap between it and the end liner 23. The end liner 23 is connected to the end wall 43 by a connecting wall 44. The connecting wall 44 has a connecting passage 45 that connects the air passage 51 to the air passage 52. The outer wall 41, inner wall 42, and end wall 43 constitute the casing structure 40. The outer wall 41 forms part of the inner shell 17 of the casing 7.

[0022] The outer liner 21 includes an opening 21b into which the fuel injector 10 is inserted. An evaporator tube 27, which is positioned in the combustion chamber S, is connected to the outer liner 21. The evaporator tube 27 includes an outer circumferential surface 27a exposed to the combustion chamber S and an inner circumferential surface 27b defining the main flow path, which is an internal flow path 31. The direction in which the flow path axis Y of the internal flow path 31 of the evaporator tube 27 extends is referred to as the flow path axis direction Y. The internal flow path 31 of the evaporator tube 27 communicates with the opening 21b of the outer liner 21. That is, the base end of the evaporator tube 27 is connected to the periphery of the opening 21b of the outer liner 21.

[0023] The fuel injector 10 is inserted into the internal flow path 31 of the evaporator tube 27 through the opening 21b of the outer liner 21. The fuel injector 10 is positioned on the flow path axis Y of the evaporator tube 27, leaving a gap between it and the inner circumferential surface 27b of the evaporator tube 27. The length of the portion of the fuel injector 10 positioned in the internal flow path 31 of the evaporator tube 27 in the flow path axis direction Y is shorter than the length of the evaporator tube 27 in the flow path axis direction Y. That is, the tip of the fuel injector 10 is located in the middle of the internal flow path 31 of the evaporator tube 27 in the flow path axis direction Y.

[0024] Air supplied from the high-pressure compressor 14 (see Figure 1) via the diffuser 8 flows into the internal passage 31 of the evaporator tube 27 through the opening 21b. The fuel injector 10 injects liquid fuel into the internal passage 31 of the evaporator tube 27. In the internal passage 31 of the evaporator tube 27, the liquid fuel injected from the fuel injector 10 mixes with air and evaporates, producing evaporated fuel. The evaporator tube 27 has a discharge port 31a at its tip that discharges the evaporated fuel from the internal passage 31 into the combustion chamber S.

[0025] The discharge port 31a of the evaporator tube 27 is spaced apart from the end liner 23 on the other side in the axial direction X and faces the end liner 23. The evaporator tube 27 extends inward in the radial direction R from the outer liner 21 and toward one side in the axial direction X. In this embodiment, the evaporator tube 27 extending inward in the radial direction R from the outer liner 21 is connected to the inner liner 22. However, the evaporator tube 27 may be spaced apart from the inner liner 22. The discharge port 31a of the evaporator tube 27 is closer to the inner liner 22 than to the outer liner 21. However, the discharge port 31a of the evaporator tube 27 does not have to be closer to the inner liner 22 than to the outer liner 21.

[0026] The outer liner 21 includes a plurality of combustion air inlet holes 21a. The plurality of combustion air inlet holes 21a include combustion air inlet holes 21a located on one side of the opening 21b in the axial direction X, and combustion air inlet holes 21a located on the other side of the opening 21b in the axial direction X. The inner liner 22 also includes a plurality of combustion air inlet holes 22a. Air supplied from the diffuser 8 flows into the combustion chamber S through the combustion air inlet holes 21a and 22a. The air that flows into the combustion chamber S from the combustion air inlet holes 21a and 22a is used for the combustion of evaporated fuel.

[0027] When the evaporated fuel discharged from the outlet 31a of the evaporator tube 27 toward the end liner 23 burns, combustion gas is generated toward the end liner 23. This combustion gas flows radially outward along the end liner 23 in the direction R, and then flows toward the other side in the axial direction X along the inner circumferential surface of the outer liner 21.

[0028] Figure 3 is a cross-sectional view taken along line III-III in Figure 4. As shown in Figure 3, the combustor 5 is provided with a plurality of baffles 28 that traverse the combustion chamber S while being spaced apart from the end liner 23 in the axial direction X. The baffles 28 connect the outer liner 21 to the inner liner 22. This increases the strength of the combustor 5. However, the baffles 28 may be connected to only one of the outer liner 21 or the inner liner 22.

[0029] Figure 4 is a view of a portion of the outer liner 21 of the combustor 5 in Figure 1, seen from the outside in the radial direction R. As shown in Figure 4, the baffles 28 are partially arranged in the combustion chamber S in the circumferential direction C, spaced apart from each other in the circumferential direction C. Each of the baffles 28 extends in the circumferential direction C. The baffles 28 are arranged so as to be separated from the evaporator tube 27 in the circumferential direction C. The axial position of the baffles 28 coincides with the axial position of the evaporator tube 27 in the axial direction X. However, the axial position of the baffles 28 may be arranged so as not to coincide with the axial position of the evaporator tube 27 in the axial direction X. For example, the baffles 28 may be arranged on the other side of the axial direction X from the evaporator tube 27.

[0030] Returning to Figure 3, the combustion chamber S includes a primary combustion zone S1 located on one side of the baffle 28 in the axial direction X, and a secondary combustion zone S2 located on the other side of the baffle 28 in the axial direction X. In the primary combustion zone S1, a portion of the combustion gas directed toward the other side of the axial direction X hits the baffle 28 and is returned to the one side of the axial direction X. This makes it easier to maintain the flame in the primary combustion zone S1 of the combustion chamber S. The remaining portion of the combustion gas directed toward the other side of the axial direction X in the primary combustion zone S1 flows into the secondary combustion zone S2 through the gap between adjacent baffles 28 in the circumferential direction C.

[0031] The baffle 28 has a convex shape toward the other side in the axial direction X when viewed in cross-section from the circumferential direction C. As a result, a portion of the combustion gas flowing toward the other side in the axial direction X along the inner circumferential surface of the outer liner 21 in the primary combustion zone S1 is smoothly guided by the baffle 28 so that it flows toward the inside in the radial direction R along the baffle 28 and then returns to the one side in the axial direction X. Therefore, a circulating flow is generated in the primary combustion zone S1, and stable flame retention performance is achieved.

[0032] Specifically, the baffle 28 has a first portion 28a and a second portion 28b. The first portion 28a extends linearly from the outer liner 21 toward the other side in the axial direction X and toward the inside in the radial direction R. The second portion 28b extends linearly from the tip of the first portion 28a toward the one side in the axial direction X and toward the inside in the radial direction R and is connected to the inner liner 22. The baffle 28 has a curved portion 28c that is convex toward the other side in the axial direction X as the boundary portion between the first portion 28a and the second portion 28b.

[0033] The outer connection position P1 of the baffle 28 to the outer liner 21 and the inner connection position P2 of the baffle 28 to the inner liner 22 are offset from each other in the axial direction X. Specifically, the inner connection position P2 is located on one side of the axial direction X compared to the outer connection position P1. As a result, the baffle 28 smoothly generates a flow that returns the combustion gas flowing along the inner circumferential surface of the outer liner 21 to the other side in the axial direction X in the primary combustion zone S1, towards the inside in the radial direction R and towards one side in the axial direction X.

[0034] As shown in Figure 2, the evaporator tube 27 has a cooling air passage 32 positioned between its outer circumferential surface 27a and inner circumferential surface 27b. The cooling air passage 32 communicates with an air passage 51 on the outside of the outer liner 21. Specifically, the outer liner 21 has a plurality of first cooling air inlet holes 21c. The plurality of first cooling air inlet holes 21c are arranged along the opening 21b. Each cooling air passage 32 of the evaporator tube 27 communicates with a cooling air inlet hole 21c of the outer liner 21. Alternatively, the outer liner 21 may be formed so that the inlet of the cooling air passage 32 communicates with the opening 21b of the outer liner 21, without providing the first cooling air inlet holes 21c.

[0035] Multiple cooling air passages 32 are arranged along the outer circumferential surface 27a of the evaporator tube 27. Each of the multiple cooling air passages 32 extends from the first cooling air inlet hole 21c of the outer liner 21 in the direction Y of the flow path axis of the evaporator tube 27. The evaporator tube 27 has multiple cooling air outlets 32a located inside its radial direction R. The cooling air outlets 32a open the ends of the cooling air passages 32 inside the radial direction R to the combustion chamber S. Specifically, the cooling air outlets 32a open toward the other side in the axial direction X. More specifically, the cooling air outlets 32a open toward the other side in the axial direction X and toward the inward direction in the radial direction R.

[0036] Air supplied from the high-pressure compressor 14 via the diffuser 8 flows into the cooling air passage 32 of the evaporator tube 27 through the first cooling air inlet 21c of the outer liner 21. This cools the evaporator tube 27 and prevents it from burning out. The air that has cooled the evaporator tube 27 is discharged from the cooling air outlet 32a into the secondary combustion zone S2 of the combustion chamber S. This discharged air is effectively used for the combustion of unburned fuel in the secondary combustion zone S2.

[0037] The cooling air passage 32 is partially positioned in the flow axis direction Y of the evaporator tube 27 so as to avoid the tip portion 27c of the evaporator tube 27. That is, the cooling air passage 32 extends from the first cooling air inlet hole 21c of the outer liner 21 along the flow axis direction Y and terminates at an intermediate position of the evaporator tube 27 in the flow axis direction Y. This prevents burnout of the evaporator tube 27 while maintaining the tip portion 27c of the evaporator tube 27 at a temperature suitable for efficient fuel evaporation.

[0038] The cooling air passage 32 is located distal to the end liner 23 of the evaporator tube 27. That is, the cooling air passage 32 is located on the other side of the axial direction X relative to the internal passage 31. The cooling air passage 32 is not located proximal to the end liner 23 of the evaporator tube 27.

[0039] Figure 5 is a cross-sectional view taken along the line V-V in Figure 2. As shown in Figure 5, when combustion gases moving from the primary combustion zone S1 to the secondary combustion zone S2 of the combustion chamber S flow around the evaporator tube 27, a wake is generated on the other side of the evaporator tube 27 in the axial direction X. In the region around the evaporator tube 27 where the wake is generated, the velocity of the combustion gases decreases and the temperature rises, so the part of the evaporator tube 27 on the other side of the axial direction X is easily heated locally. In this embodiment, the cooling air passage 32 is located distal to the end liner 23 of the evaporator tube 27, so the part of the evaporator tube 27 that is easily heated locally is effectively cooled.

[0040] As shown in Figure 3, the baffle 28 includes a plurality of cooling air passages 35 located inside the baffle 28. The cooling air passages 35 communicate with an air passage 51 on the outside of the outer liner 21. Specifically, the outer liner 21 has a plurality of second cooling air inlet holes 21d. The plurality of second cooling air inlet holes 21d are arranged in the circumferential direction C. Each of the cooling air passages 35 of the baffle 28 communicates with a second cooling air inlet hole 21d of the outer liner 21.

[0041] Multiple cooling air passages 35 are arranged in the circumferential direction C. Each of the multiple cooling air passages 35 extends from the second cooling air inlet hole 21d of the outer liner 21 toward the inner liner 22. The baffle 28 has multiple cooling air outlets 35a located inward in its radial direction R. The cooling air outlets 35a open the ends of the cooling air passages 35 inward in the radial direction R to the combustion chamber S. Specifically, the cooling air outlets 35a open toward the other side in the axial direction X. More specifically, the cooling air outlets 35a open toward the other side in the axial direction X and toward the inward direction R.

[0042] The air supplied from the diffuser 8 flows into the cooling air flow path 35 of the baffle 28 through the second cooling air introduction hole 21d of the outer liner 21. As a result, the baffle 28 is efficiently cooled from the inside, and burning of the baffle 28 is prevented. The air that has cooled the baffle 28 is discharged from the cooling air discharge port 35a into the secondary combustion zone S2 of the combustion chamber S. The discharged air is effectively used for combustion of unburned fuel in the secondary combustion zone S2. Since the air discharged from the cooling air discharge port 35a of the baffle 28 flows along the outer surface in the radial direction R of the inner liner 22 toward the other side in the axial direction X, turbulence of the flow in the combustion chamber S is suppressed, and this also contributes to cooling of the inner liner 22.

[0043] As described above, the foregoing embodiments have been described as examples of the technology disclosed in the present application. However, the technology in the present disclosure is not limited to this, and is also applicable to embodiments in which changes, replacements, additions, omissions, etc. are appropriately made. Further, it is also possible to form a new embodiment by combining the respective components described in the foregoing embodiments. For example, a part of the configuration or method in one embodiment may be applied to another embodiment, and a part of the configuration in an embodiment can be arbitrarily extracted separately from other configurations in that embodiment. Further, among the components described in the attached drawings and the detailed description, there are not only components essential for solving the problems, but also components not essential for solving the problems for exemplifying the technology.

[0044] [Aspect] The foregoing embodiments are specific examples of the following aspects.

[0045] (Aspect 1) A reverse-flow combustor for a gas turbine having a rotating shaft with an axis extending in the axial direction, comprising: an annular outer liner extending in the circumferential direction around the axis; an annular inner liner facing the outer liner from the inner side in the radial direction orthogonal to the axis; an annular end liner disposed on one side in the axial direction with respect to the outer liner and the inner liner, connecting the outer liner to the inner liner; a combustion chamber defined by the outer liner, the inner liner, and the end liner; and a baffle partially disposed in the combustion chamber in the circumferential direction, connecting the outer liner to the inner liner so as to cross the combustion chamber while being spaced apart from the end liner in the axial direction. A reverse-flow combustor for a gas turbine.

[0046] According to this configuration, since the flow of combustion gas toward the downstream side away from the end liner in the combustion chamber is partially obstructed by the baffle, the flame in the combustion chamber is likely to be maintained. Also, since the outer liner and the inner liner are connected to each other by the baffle, the strength of the combustor is increased. Therefore, the flame-holding performance and vibration resistance performance of the reverse-flow combustor for a gas turbine can be enhanced.

[0047] (Aspect 2) The reverse-flow combustor for a gas turbine according to Aspect 1, wherein the baffle has a shape convex toward the other side in the axial direction in a cross-sectional view seen from the circumferential direction.

[0048] According to this configuration, in the primary combustion zone between the baffle and the end liner in the combustion chamber, the combustion gas flowing toward the other side in the axial direction, i.e., the downstream side of the combustion chamber, is partially guided by the baffle so as to return to the one side in the axial direction, i.e., the upstream side of the combustion chamber. Thus, a circulating flow occurs in the primary combustion zone, and stable flame-holding performance can be exhibited.

[0049] (Aspect 3) The backflow combustor for a gas turbine according to aspect 2, wherein the baffle includes a first portion extending linearly from the outer liner toward the other side in the axial direction and toward the radially inward, and a second portion extending linearly from the tip of the first portion toward the one side in the axial direction and toward the radially inward, and connected to the inner liner.

[0050] This configuration allows for improved baffle manufacturing efficiency, as the baffle is composed of a first and second section that extend linearly. Furthermore, regardless of the radial position at which the combustion gas flowing toward the other axial direction strikes the baffle, the flow velocity of the combustion gas is stably reduced by contact with the baffle, thereby stabilizing the circulating flow in the primary combustion zone.

[0051] (Aspect 4) A reverse-flow combustor for a gas turbine according to any one of aspects 1 to 3, wherein the connection position of the baffle to the outer liner and the connection position of the baffle to the inner liner are offset from each other in the axial direction.

[0052] This configuration increases the design freedom regarding the shape of the region between the end liner and the baffle, allowing the baffle to shape the circulation flow generation region appropriately.

[0053] (Aspect 5) A backflow combustor for a gas turbine according to aspect 4, further comprising an evaporator tube including a discharge port for discharging evaporated fuel toward the end liner, wherein the discharge port of the evaporator tube is closer to the inner liner than to the outer liner, and the connection position of the baffle to the inner liner is located on one side in the axial direction than the connection position of the baffle to the outer liner.

[0054] With this configuration, the evaporated fuel discharged from the evaporator tube outlet strikes the end liner and flows radially outward and axially to the other side. As a result, the baffle smoothly generates a flow that returns the combustion gas radially inward and axially to one side.

[0055] (Aspect 6) The backflow combustor for a gas turbine according to any one of aspects 1 to 5, wherein the baffle includes a cooling air passage arranged inside the baffle.

[0056] This configuration allows for efficient cooling of the baffle from the inside, reliably preventing burnout of the baffle.

[0057] (Aspect 7) A backflow combustor for a gas turbine according to any one of aspects 1 to 6, further comprising an evaporator disposed in the combustion chamber, wherein the outer liner includes an opening into which a fuel injector is inserted, the evaporator is connected to the outer liner such that the internal flow path of the evaporator communicates with the opening, and the axial position of the baffle is positioned to coincide with the axial position of the evaporator.

[0058] This configuration allows the area where the circulating flow generated by the baffle is produced to be of an appropriate size.

[0059] 1 Gas turbine 2 Rotating shaft 5 Combustor 10 Fuel injector 21 Outer liner 21b Opening 21c First cooling air inlet 21d Second cooling air inlet 22 Inner liner 23 End liner 27 Evaporator tube 27a Outer surface 27b Inner surface 27c Tip 28 Baffle 28a First part 28b Second part 28c Bent part 31 Internal flow path 32 Cooling air flow path 32a Cooling air outlet 35 Cooling air flow path 35a Cooling air outlet C Circumferential direction P1 Outer connection position P2 Inner connection position R Radial direction S Combustion chamber X Axial direction Y Flow path axis direction

Claims

A reverse-flow combustor for a gas turbine having a rotating shaft with an axis extending in the axial direction, An annular outer liner extending in the circumferential direction around the aforementioned axis, An annular inner liner facing the outer liner from the inside in the radial direction perpendicular to the aforementioned axis, An annular end liner is positioned on one side in the axial direction relative to the outer liner and the inner liner, and connects the outer liner to the inner liner. The combustion chamber defined by the outer liner, the inner liner and the end liner, A backflow combustor for a gas turbine, comprising: a baffle partially arranged in the combustion chamber in the circumferential direction, the baffle connecting the outer liner to the inner liner so as to traverse the combustion chamber while spaced apart from the end liner in the axial direction; and a baffle. 　 The baffle has a shape that is convex toward the other side in the axial direction when viewed in cross-section from the circumferential direction, according to claim 1, a reverse-flow combustor for a gas turbine. 　 The aforementioned baffle is A first portion extending linearly from the outer liner toward the other side in the axial direction and toward the inside in the radial direction, A second portion extends linearly from the tip of the first portion toward one side in the axial direction and toward the inside in the radial direction, and is connected to the inner liner, A reverse-flow combustor for a gas turbine according to claim 2, including the above. 　 The reverse-flow combustor for a gas turbine according to any one of claims 1 to 3, wherein the connection position of the baffle to the outer liner and the connection position of the baffle to the inner liner are offset from each other in the axial direction. 　 The system further includes an evaporator tube with a discharge port for discharging evaporated fuel toward the end liner, The discharge port of the evaporator tube is closer to the inner liner than to the outer liner. The reverse-flow combustor for a gas turbine according to claim 4, wherein the connection position of the baffle to the inner liner is located on one side in the axial direction than the connection position of the baffle to the outer liner. 　 The backflow combustor for a gas turbine according to any one of claims 1 to 3, wherein the baffle includes a cooling air passage disposed inside the baffle. 　 The combustion chamber further comprises an evaporator tube, The outer liner includes an opening into which a fuel injector is inserted. The evaporator tube is connected to the outer liner such that the internal flow path of the evaporator tube communicates with the opening. The reverse-flow combustor for a gas turbine according to any one of claims 1 to 3, wherein the axial position of the baffle is arranged to coincide with the axial position of the evaporator tube.

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