JP2015218946A - Gas turbine combustor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas turbine combustor with a reduced head loss of compressed-air in a gas turbine combustor combining a diffusion combustion burner and a pre-mixture combustion burner.SOLUTION: A gas turbine combustor comprises: a diffusion combustion burner disposed at a shaft center of a combustion chamber; a plurality of pre-mixture combustion burners disposed in a circumference of the diffusion combustion burner; a blending chamber disposed inside each of the pre-mixture combustion burners for mixing fuel with air; an air stream passage for endowing air flowing into the blending chamber with a swirl component; and a burner cover containing the diffusion combustion burner and the plurality of pre-mixture combustion burners and including a plurality of air introduction ports for introducing air to the diffusion combustion burner and the plurality of pre-mixture combustion burners, in which the air introduction ports provided in the burner cover are arranged in a circumferential position so as to oppose the middle of the two pre-mixture combustion burners adjacent to each other.

Description

  The present invention relates to a gas turbine combustor.

  In recent years, various environmental problems have been highlighted, and it is important to reduce the emission of nitrogen oxides (hereinafter referred to as NOx), which is an environmental burden, from the viewpoint of environmental protection in gas turbine combustors as well. It has become. Further, from the viewpoint of fuel diversification, attention has been focused on a dual-fuel compatible gas turbine combustor capable of burning both liquid fuel and gaseous fuel.

  In a dual-fuel compatible gas turbine combustor, a premixed combustion system has been proposed to reduce NOx emissions. In the premix combustion method, fuel and air are mixed in advance and then burned, thereby suppressing the generation of a local high temperature region in the combustion chamber and reducing the amount of thermal NOx generated. There is a gas turbine combustor that is a dual-fuel compatible gas turbine combustor that employs a premixed combustion system and combines a diffusion combustion burner and a plurality of premixed combustion burners (see, for example, Patent Document 1).

JP 2010-236739 A

  In the conventional gas turbine combustor described above, a diffusion combustion burner having a mixing chamber for mixing fuel and compressed air is provided at the axial center position of the combustor head, and the fuel and compressed air are provided around the diffusion combustion burner. A plurality of premixed combustion burners having mixing chambers are mixed and arranged concentrically. For this reason, the flow path shape for introducing compressed air into the plurality of burners tends to be complicated.

  Specifically, the mixing chamber of each burner is provided with a plurality of air holes in the circumferential direction that serve as flow paths into which compressed air is introduced. Since a diffusion combustion burner is provided at the axial center position and a plurality of premixed combustion burners are arranged on the outer periphery of the diffusion combustion burner, the flow path of the compressed air is complicated through the gaps between these burners, and the periphery of the air holes of the burner is Depending on the position in the direction, the inflow angle of the compressed air flowing into the air holes may vary. In addition, when the inflow angle of the compressed air flowing into the air hole increases, the flow of the compressed air peels from the wall surface of the air hole flow path, and a vortex that does not contribute to the mixing and flame holding of the fuel and the compressed air is formed. The possibility of increased pressure loss arises. When the pressure loss increases, there arises a problem that the thermal efficiency of the gas turbine decreases.

  The present invention has been made based on the above-described matters, and an object of the present invention is to provide a gas turbine combustor that combines a diffusion combustion burner and a premixed combustion burner, in which the pressure loss of compressed air is reduced. Is to provide.

  In order to solve the above problems, for example, the configuration described in the claims is adopted. The present application includes a plurality of means for solving the above-mentioned problems. For example, a diffusion combustion burner disposed at the center of the combustor and a plurality of pre-arrangements disposed on the outer periphery of the diffusion combustion burner. A mixed combustion burner, a mixing chamber inside the premixed combustion burner for mixing fuel and air, an air flow path for imparting a swirl component to the air flowing into the mixing chamber, and the diffusion combustion A gas turbine combustor including a burner and a plurality of premixed combustion burners, and a burner cover having a plurality of air inlets for introducing air into the diffusion combustion burners and the plurality of premixed combustion burners The circumferential position of the air inlet provided in the burner cover is configured to face the middle of two adjacent premixed combustion burners.

  ADVANTAGE OF THE INVENTION According to this invention, in the gas turbine combustor which combined the diffusion combustion burner and the premixed combustion burner, the highly efficient gas turbine combustor which reduced the pressure loss of compressed air can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram illustrating a side sectional view of a main part of a first embodiment of a gas turbine combustor according to the present invention together with a schematic diagram of an entire gas turbine plant. It is an expanded sectional side view of the gas turbine combustor head of 1st Embodiment of the gas turbine combustor of this invention. FIG. 3 is a transverse cross-sectional view in the radial direction of a gas turbine combustor head taken along line III-III in FIG. 2. It is the cross-sectional view which expanded the A section and A 'section of FIG. 3A. It is a cross-sectional view of the radial direction of the conventional gas turbine combustor head. It is the cross-sectional view which expanded the B section of FIG. 4A. It is a cross section of the radial direction of the gas turbine combustor head of a 2nd embodiment of the gas turbine combustor of the present invention. It is a cross section of the radial direction of the gas turbine combustor head of a 3rd embodiment of the gas turbine combustor of the present invention.

  Embodiments of a gas turbine combustor according to the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing a side sectional view of an essential part of a first embodiment of a gas turbine combustor of the present invention together with a schematic diagram of an entire gas turbine plant.
The gas turbine plant shown in FIG. 1 mainly includes a compressor 1 that compresses air sucked from the atmosphere to generate high-pressure compressed air 100, and compressed air 100 and liquid fuel 201 or gas introduced from the compressor 1. Combustor 2 that mixes and burns fuel 202 to generate combustion gas 50, turbine 3 to which combustion gas 50 generated by combustor 2 is introduced, and power generation that is rotated by driving of turbine 3 to generate electric power Machine 4. In addition, the compressor 1, the turbine 3, and the generator 4 are connected with the rotating shaft. The rotational power transmitted to the compressor 1 is used as compression power, and the rotational power transmitted to the generator 4 is converted into electric energy.

  The combustor 2 includes an outer cylinder 10 that is a pressure vessel, a cylindrical liner 12 that forms a combustion chamber 11 inside the outer cylinder 10, and a transition piece 13 that is connected to the downstream side of the liner 12. ing. The combustor head on the upstream side of the liner 12 is provided with a diffusion combustion burner 20 having excellent combustion stability at the axial center position, and around the diffusion combustion burner 20 is effective for reducing NOx. A plurality of premixed combustion burners 30 for performing premixed combustion are arranged concentrically.

  Next, the structure of the combustor head will be described with reference to FIGS. 2 to 3B. 2 is an enlarged side sectional view of the gas turbine combustor head according to the first embodiment of the gas turbine combustor of the present invention. FIG. 3A is a radial direction of the gas turbine combustor head taken along line III-III in FIG. FIG. 3B is an enlarged cross-sectional view of part A and part A ′ of FIG. 3A. 2 to 3B, the same reference numerals as those shown in FIG. 1 are the same parts, and thus detailed description thereof is omitted.

  A diffusion combustion burner 20 shown in FIG. 2 includes a diffusion combustion burner liquid fuel nozzle 21 and a diffusion combustion burner mixing chamber 22 formed in a hollow conical shape downstream of the diffusion combustion burner liquid fuel nozzle 21. . A plurality of diffusion combustion burner air holes 23 are formed on the wall surface of the hollow conical diffusion combustion burner mixing chamber 22 to impart a swirl component to the air introduced into the diffusion combustion burner mixing chamber 22. On the outer periphery of the diffusion combustion burner liquid fuel nozzle 21, the same number of gaseous fuel nozzles 24 as that of the diffusion combustion burner air holes 23 are arranged at opposite positions upstream of each diffusion combustion burner air hole 23.

  On the other hand, the plurality of premixed combustion burners 30 arranged concentrically around the diffusion combustion burner 20 are provided with a mixing chamber 31 in order to promote mixing of fuel and air. The mixing chamber 31 has a hollow conical shape portion in which a reduced diameter portion is arranged at the upstream axial center and a diameter enlarged portion is arranged on the downstream side, and a hollow cylindrical shape formed downstream from the edge of the downstream end of the hollow conical shape portion. Department. In other words, the mixing chamber 31 has an inner peripheral part composed of a hollow conical part and a hollow cylindrical part, a wall surface part covering the inner peripheral part, and an outer peripheral part which is the outer periphery of the wall part.

  A plurality of air holes 32 for introducing combustion air are formed in the wall surface of the mixing chamber 31 of the premixed combustion burner 30 in the axial direction and the circumferential direction. A gaseous fuel injection hole 33 for jetting is provided.

  A liquid fuel nozzle 34 that injects the liquid fuel 201 into the mixing chamber 31 is disposed at the axial center position of the premix combustion burner 30. Further, a diffusion burner 20 and a burner cover 40 surrounding the premixed combustion burner 30 are disposed on the outer peripheral side of the premixed combustion burner 30, and the diffusion combustion burner 20 and the premixed combustion burner 30 are disposed at the downstream end of the burner cover 40. A burner plate 41 for supporting the burner is disposed integrally with the burner cover 40.

  A plurality of air inlets 42 for introducing the compressed air 100 into the burner cover 40 are formed in the burner cover 40 in the circumferential direction.

  FIG. 3A shows the structure of the diffusion combustion burner 20, the premixed combustion burner 30, the burner cover 40, and the air inlet 42 taken along the line III-III in FIG. In the present embodiment, the circumferential position of the air inlet 42 provided in the burner cover 40 is configured to face the middle of two adjacent premixed combustion burners 30. In the present embodiment, three air inlets 42 are arranged for six premixed combustion burners 30, and the air inlets 42 are arranged between two adjacent premixed combustion burners 30. The place (X part) and the place (Y part) which are not arrange | positioned are provided alternately. In other words, two adjacent premixed combustion burners 30 constitute one group, and the air inlet 42 is provided at a position of the burner cover 40 facing the middle in the circumferential direction of the one group.

  The air hole 32 of the premixed combustion burner 30 is formed by shifting the center of the hole in the tangential direction of a circle indicating the inner peripheral portion of the mixing chamber 31. This imparts a swirl to the air flowing into the mixing chamber 31 and forms a swirl flow 35 of air.

  Furthermore, in the present embodiment, the swirling direction of the compressed air 100 passing through the air holes 32 provided in the premixed combustion burner 30 is such that the air inlet 42 adjacent to the premixed combustion burner 30 is located with respect to the combustor shaft center. When it is located clockwise, the turning direction is clockwise, and when it is located counterclockwise, the turning direction is counterclockwise.

  Specifically, in FIG. 3A, the premixed combustion burner in which the uppermost air inlet 42 is positioned counterclockwise with the premixed combustion burner 30 positioned clockwise with respect to the center of the combustor axis as A ′. When 30 is A, the premixed combustion burner 30 of A ′ indicates the inner peripheral portion of the mixing chamber 31 with the hole center of the air hole 32 so that the compressed air 100 passing through the air hole 32 turns clockwise. The circle is formed so as to be shifted in a tangential direction positioned clockwise with respect to the combustor axis center. Further, the premixed combustion burner 30 of A has a hole center of the air hole 32 with respect to a circle indicating the inner peripheral portion of the mixing chamber 31 so that the compressed air 100 passing through the air hole 32 turns counterclockwise. It is formed by shifting in a tangential direction located counterclockwise with respect to the combustor shaft center.

  Next, the flow state of the fuel and air in the gas turbine combustor 2 in the above configuration will be described with reference to FIGS. 1 and 2. The air 100 compressed by the compressor 1 flows into the combustor 2 through the diffuser 5 and passes between the outer cylinder 10 and the liner 12. A part of the compressed air 100 flows into the combustion chamber 11 as the cooling air 101 of the liner 12. The compressed air 100 other than the cooling air 101 flows into the burner cover 40 through the air inlet 42 provided in the burner cover 40 and flows into the diffusion combustion burner 20 and the premixed combustion burner 30.

  The compressed air 100 flowing into the diffusion combustion burner 20 flows into the diffusion combustion burner mixing chamber 22 as diffusion combustion air 102 and is ejected from the liquid fuel 201 or the gas fuel nozzle 24 ejected from the liquid fuel nozzle 21 for the diffusion combustion burner. It reacts with the gaseous fuel 202 to form a diffusion flame 103.

  The compressed air 100 that has flowed into the premixed combustion burner 30 flows into the mixing chamber 31 as premixed combustion air 104, and the liquid fuel 201 injected from the liquid fuel nozzle 34 or the gaseous fuel ejected from the gaseous fuel injection hole 33. After mixing with 202, a premixed flame 105 is formed. The high-temperature combustion gas 50 generated by the diffusion flame 103 and the premixed flame 105 passes through the transition piece 13 installed downstream of the combustor 2 and flows into the turbine 3. The combustion gas 50 is discharged through an exhaust duct after taking out work by the turbine 3 and the generator 4.

  In the gas turbine combustor 2 having the above-described configuration, from the start of the gas turbine device to the ascending speed and low load conditions, the operation is performed by diffusing and burning the liquid fuel 201 or the gaseous fuel 202 using the diffusion combustion burner 20 alone. Next, under a high load condition in which the fuel flow rate further increases, liquid fuel 201 or gaseous fuel 202 is supplied to the premixed combustion burner 30 in addition to the diffusion combustion burner 20 for premixed combustion, and diffusion combustion and premixed combustion are performed. Carry out the combined operation. At this time, by controlling the ratio of the combustion load between the diffusion combustion and the premixed combustion, it is possible to operate with both low NOx and stable combustion. As for the ratio of the combustion load due to diffusion combustion and premixed combustion, diffusion combustion mainly increases the ratio during partial load operation, and premixed combustion mainly increases the ratio near the rated load.

  Next, the flow state of the compressed air and fuel near the burner cover 40 and the premixed combustion burner in the present embodiment will be described with reference to FIGS. 3A and 3B. Compressed air 100 flows into the burner cover 40 from the air inlet 42, partly flows into the mixing chamber 31 as premixed combustion air 104 through the air holes 32 provided in the premixed combustion burner 30, and the rest is premixed combustion. It passes between the burners 30 (X portion) and collides with the side surface of the diffusion combustion burner 20.

  The compressed air 100 that has collided with the side surface of the diffusion combustion burner 20 merges with the compressed air 100 flowing in from another air inlet 42, and a part of the compressed air 100 is diffused combustion air 102 through the diffusion combustion burner air holes 23. 22 flows in. The remaining compressed air 100 passes between the premixed combustion burners 30 (Y portion) and flows into the mixing chamber 31 through the air holes 32. For this reason, a flow field in which the compressed air 100 swirls around the outer periphery of the premixed combustion burner 30 is formed around the premixed combustion burner 30.

  For example, a flow field in which the compressed air 100 flowing in from the uppermost air inlet 42 swirls counterclockwise is formed on the outer periphery of the premixed combustion burner 30 shown by the symbol A, and the premixed burner 30 indicated by the symbol A ′ is formed. A flow field in which the compressed air 100 swirls clockwise is formed on the outer periphery of the mixed combustion burner 30. In addition, the compressed air 100 flowing into each mixing chamber 31 is given a swirling component by the air holes 32 formed by shifting the center of the hole in the tangential direction of the circle indicating the inner peripheral portion of the mixing chamber 31. A swirling flow 35 is formed.

  In the present embodiment, the swirling direction of the compressed air 100 passing through the air holes 32 provided in the premixed combustion burner 30 is such that the air inlet 42 adjacent to the premixed combustion burner 30 is clockwise with respect to the combustor shaft center. When it is located in the clockwise direction, the turning direction is clockwise. When it is located in the counterclockwise direction, the turning direction is counterclockwise.

  For example, the premixed combustion burner 30 illustrated by the symbol A has a swirl flow formed in the mixing chamber 31 by the air holes 32 because the adjacent air inlet 42 is located counterclockwise with respect to the center of the combustor axis. The turning direction of 35 is counterclockwise. On the other hand, the premixed combustion burner 30 illustrated by the symbol A ′ has a swirl flow formed in the mixing chamber 31 by the air holes 32 because the adjacent air inlet 42 is positioned clockwise with respect to the center of the combustor axis. The turning direction of 35 is clockwise.

  That is, by configuring the gas turbine combustor as in the present embodiment, as shown in FIG. 3B, the swirling direction of the compressed air 100 flowing around the outer periphery of the premixed combustion burner 30 and the inside of the premixed combustion burner 30 The swirling direction of the swirling flow 35 can be the same direction. As a result, the inflow angle α, which is the angle that flows into the air hole 32 with respect to the traveling direction of the compressed air 100 in the flow field swirling around the outer periphery of the premixed combustion burner 30, is substantially constant regardless of the circumferential position of the air hole 32. can do. Moreover, since the inflow angle α can be suppressed to 90 degrees or less, it is possible to suppress the compressed air 100 from being separated from the wall surface of the flow path of the air hole 32. As a result, an increase in pressure loss of the gas turbine combustor can be prevented.

  Next, for comparison with the present embodiment, the flow state of compressed air and fuel near the burner cover 40 and the premixed combustion burner in the conventional gas turbine combustor will be described with reference to FIGS. 4A and 4B. FIG. 4A is a radial cross-sectional view of a conventional gas turbine combustor head, and FIG. 4B is an enlarged cross-sectional view of portion B of FIG. 4A. 4A and 4B, the same reference numerals as those shown in FIGS. 1 to 3B are the same parts, and thus detailed description thereof is omitted.

  In the conventional gas turbine combustor, as shown in FIG. 4A, the air introduction portion 43 provided in the burner cover 40 is formed in a porous shape around the burner cover, and is formed in the mixing chamber 31 of the premixing burner 30. The difference is that the swirling direction of the swirling flow 35 is not defined with respect to the air introduction portion 43, and the rest of the configuration is the same. The compressed air 100 flowing into the burner cover 40 is rectified by making the air introduction part 43 porous.

  In such a configuration, the compressed air 100 flowing in from the air introduction portion 43 of the burner cover 40 collides with the premixed combustion burner 30, passes through both sides of the premixed combustion burner 30, and heads toward the combustor shaft central portion. A part of the gas flowed into the mixing chamber 31 through the air holes 32, and the other gas flowed into the diffusion combustion burner mixing chamber 22 through the diffusion combustion burner air holes 23. Therefore, depending on the position in the circumferential direction of the air hole 32 of the premixed combustion burner 30, the inflow angle α, which is the angle flowing into the air hole 32 with respect to the traveling direction of the compressed air 100 in the flow field swirling around the outer periphery of the premixed combustion burner 30 May increase.

  As shown in FIG. 4B, when the inflow angle α increases to 90 ° or more, the compressed air 100 as the premixed combustion air 104 is peeled off from the wall surface of the air hole 32, and the flow path of the air hole 32. A circulation flow 36 is formed therein. The circulating flow 36 is an unnecessary flow when the compressed air 100 flows into the mixing chamber 31 and results in a loss of energy, causing a pressure loss to increase in the premixed combustion burner 30.

  Further, in the conventional structure, when the circulation flow 36 is formed in the flow path of the air hole 32, the compressed air 100 becomes difficult to flow, and a circumferential deviation occurs in the flow rate of the compressed air 100. If an air flow rate deviation occurs in the compressed air 100 flowing into the premixed combustion burner 30, the fuel concentration in the mixing chamber 31 increases, the local flame temperature of the premixed flame 105 increases, and the NOx emission amount may increase. There was a problem that occurred.

  In the present embodiment, the swirling direction of the compressed air 100 flowing on the outer periphery of the premixed combustion burner 30 and the swirling direction of the swirling flow 35 inside the premixed combustion burner 30 can be made the same direction. 100 can be prevented from peeling from the wall surface of the flow path of the air hole 32, and the pressure loss generated in the premix burner 30 can be reduced.

  According to the first embodiment of the gas turbine combustor of the present invention described above, in the gas turbine combustor in which the diffusion combustion burner 20 and the premixed combustion burner 30 are combined, high efficiency with reduced pressure loss of compressed air is achieved. Gas turbine combustor can be provided.

  Further, according to the first embodiment of the gas turbine combustor of the present invention described above, the formation of the circulation flow 36 in the flow path of the air hole 32 of the premixed combustion burner 30 can be suppressed. The flow rate deviation of the compressed air 100 flowing into the mixed burner 30 can be reduced, the rise in the local flame temperature of the premixed flame 105 is suppressed, and low NOx combustion is possible.

  Hereinafter, a second embodiment of the gas turbine combustor of the present invention will be described with reference to the drawings. FIG. 5 is a radial cross-sectional view of the gas turbine combustor head according to the second embodiment of the gas turbine combustor of the present invention. In FIG. 5, the same reference numerals as those shown in FIGS. 1 to 4 are the same parts, and detailed description thereof is omitted.

  The second embodiment of the gas turbine combustor according to the present invention shown in FIG. 5 is configured with almost the same equipment as the first embodiment, but the following configuration is different. In the present embodiment, a guide plate 44 that protrudes inside the burner cover 40 is provided at the edge of each air inlet 42, and a side surface of the diffusion combustion burner 20 that is adjacent to the adjacent two disposed on the outer periphery. The difference is that a distribution plate 45 protruding toward the outer periphery of the combustor is provided at each of a plurality of positions opposed to the middle of each premixed combustion burner 30. In addition, diffusion combustion burner air holes 23 are provided in each region on the side surface of the diffusion combustion burner 20 divided by the distribution plate 45, and each of these has a total opening area of the diffusion combustion burner air holes 23. It is formed so as to be even in the region.

  In the gas turbine combustor in the present embodiment, when the compressed air 100 flows into the burner cover 40 from the air inlet 42, the air is rectified in the direction toward the diffusion combustion burner 20 by the guide plate 44. The compressed air 100 rectified by the guide plate 44 collides with the distribution plate 45 disposed on the side surface of the diffusion combustion burner 20, is distributed on both sides of the distribution plate 45, and then collides with the side surface of the diffusion combustion burner 20.

  A part of the compressed air 100 colliding with the side surface of the diffusion combustion burner 20 flows into the diffusion combustion burner mixing chamber 22 through the diffusion combustion burner air hole 23, and the rest passes between the premix combustion burner 30 (Z section). Toward the outer peripheral side of the combustor 2. Part of the compressed air 100 that has passed between the premixed combustion burners 30 flows into the mixing chamber 31 through the air holes 32, and the rest flows along the burner cover 40 and the guide plate 44. The compressed air 100 flows in and flows again toward the diffusion combustion burner 20.

  As in the present embodiment, by providing a guide plate 44 that protrudes inside the burner cover 40 at the edge of each air inlet 42, when the compressed air 100 flows into the burner cover 40, it is near the air inlet 42. It is possible to suppress the formation of the circulation flow and reduce the pressure loss.

  In addition, when a plurality of distribution plates 45 are arranged on the side surface of the diffusion combustion burner 20 as in the present embodiment, the distribution plates 45 are positioned in the same phase in the circumferential direction as the air inlet 42, so that the diffusion combustion burner 20 The impinging compressed air 100 can be evenly distributed on both sides of the distribution plate 45. For this reason, the flow rate deviation in the circumferential direction of the compressed air 100 flowing on the outer periphery of the premixed combustion burner 30 is reduced, and the flow rate of air flowing into the premixed combustion burner 30 is equalized. As a result, an increase in the fuel concentration in the mixing chamber 31 and an increase in the local flame temperature of the premixed flame 105 caused by a deviation in the flow rate of air flowing into the premixed combustion burner 30 can be suppressed, and an increase in NOx emission can be suppressed.

  According to the second embodiment of the gas turbine combustor of the present invention described above, the same effect as that of the first embodiment can be obtained.

  Further, according to the above-described second embodiment of the gas turbine combustor of the present invention, it is a side surface of the diffusion combustion burner 20, in the middle of two adjacent premixed combustion burners 30 arranged on the outer periphery. Since the distribution plate 45 protruding toward the outer peripheral side of the combustor is provided at each of a plurality of opposing positions, the compressed air 100 that has collided with the diffusion combustion burner 20 flows along the distribution plate 45 toward the outer peripheral side of the combustor. Can be turned. As a result, the flow in the vicinity of the diffusion combustion burner 20 can be rectified, and the occurrence of pressure loss can be suppressed.

  Further, according to the above-described second embodiment of the gas turbine combustor of the present invention, the flow rate of the compressed air 100 is substantially uniform in each region on the side surface of the diffusion combustion burner 20 partitioned by the distribution plate 45. . Further, since the opening area of the diffusion combustion burner air hole 23 in each region on the side surface of the diffusion combustion burner 20 is configured to be uniform, the flow rate and flow velocity of the compressed air 100 flowing into each diffusion combustion burner air hole 23 are changed. Directional deviation can be reduced. This can prevent the formation of the diffusion flame 103 biased with respect to the axial direction of the combustion chamber 11. As a result, the combustion stability of the diffusion flame 103 and the premixed flame 105 can be ensured, and the temperature rise of the liner 12 can be suppressed.

  Hereinafter, a third embodiment of the gas turbine combustor of the present invention will be described with reference to the drawings. FIG. 6 is a radial cross-sectional view of the gas turbine combustor head portion of the third embodiment of the gas turbine combustor of the present invention. In FIG. 6, the same reference numerals as those shown in FIGS. 1 to 5 are the same parts, and detailed description thereof is omitted.

  The third embodiment of the gas turbine combustor according to the present invention shown in FIG. 6 is configured with the same devices as the first embodiment, but the following configuration is different. In the present embodiment, a plurality of partition plates 46 that connect the inner wall of the burner cover 40 and the side surfaces of the diffusion combustion burner 20 are provided so as to separate adjacent premixed combustion burners 30, and the burner cover 40 and the partition plate are provided. 46, the point where one premixed combustion burner 30 is arranged in a space partitioned by the diffusion combustion burner 20, and the circumferential direction in contact with one partition plate in the burner cover 40 forming the partitioned space The difference is that an air inlet 42 is provided at the position.

  With such a configuration, the air inlet 42 is disposed at a position where the phase in the circumferential direction is shifted from the axial center of the premixed combustion burner 30. In addition, diffusion combustion burner air holes 23 are provided in each region on the side surface of the diffusion combustion burner 20 divided by the partition plate 46, and these have a total opening area of each diffusion combustion burner air hole 23. It is formed so as to be even in the region.

  In the gas turbine combustor according to the present embodiment, the compressed air 100 flowing into the burner cover 40 from the air inlet 42 flows along the partition plate 46 and collides with the side surface of the diffusion combustion burner 20.

  A part of the compressed air 100 that collides with the side surface of the diffusion combustion burner 20 flows into the diffusion combustion burner mixing chamber 22 through the diffusion combustion burner air hole 23, and the rest travels along the partition plate 46 toward the outer peripheral side of the combustor 2. . Therefore, a flow field of the compressed air 100 that swirls around the premixed combustion burner 30 is formed around the premixed combustion burner 30.

  By configuring the combustor 2 as in the present embodiment, the flow of the compressed air 100 flowing in from the air inlet 42 is restricted by the partition plate 46, and thus the premixed combustion burner 30 in the partition plate 46 and It flows out from the diffusion combustion burner 20 to the combustion chamber 11. At this time, since the cross-sectional area between the burner cover 40 and the outer cylinder 10 is larger than the cross-sectional area of the air inlet 42, the air inlet 42 becomes an orifice. For this reason, the compressed air 100 is evenly distributed to the air introduction ports 42, and the flow rate of the compressed air 100 flowing into the premixed combustion burners 30 can be made uniform.

  For this reason, the flow rate deviation in the circumferential direction of the compressed air 100 flowing on the outer periphery of the premixed combustion burner 30 is reduced, and the flow rate of air flowing into the premixed combustion burner 30 is equalized. As a result, an increase in the fuel concentration in the mixing chamber 31 and an increase in the local flame temperature of the premixed flame 105 caused by a deviation in the flow rate of air flowing into the premixed combustion burner 30 can be suppressed, and an increase in NOx emission can be suppressed.

  According to the third embodiment of the gas turbine combustor of the present invention described above, the same effects as those of the first embodiment can be obtained.

  Further, according to the third embodiment of the gas turbine combustor of the present invention described above, the positional relationship between the air inlet 42 and the premixed combustion burner 30 is all rotationally symmetric in the space partitioned by the partition plate 46. It has become. For example, in the present embodiment, in any premixed combustion burner 30, the corresponding air inlet 42 is located counterclockwise with respect to the combustor shaft center. For this reason, all the swirling directions of the air holes 32 provided in the premixed combustion burner 30 are counterclockwise, and the structure of the premixed combustion burner 30 to be used can be unified. As a result, when assembling the premixed combustion burner 30, the risk of making a wrong turning direction can be reduced. Moreover, since the premixed combustion burner 30 can be unified into one type, the management cost of parts can be reduced.

  The present invention is not limited to the above-described first to third embodiments, and includes various modifications. The above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to the one having all the configurations described.

DESCRIPTION OF SYMBOLS 1 Compressor 2 Combustor 3 Turbine 4 Generator 5 Diffuser 10 Outer cylinder 11 Combustion chamber 12 Liner 13 Transition piece 20 Diffusion combustion burner 21 Diffusion combustion burner nozzle 22 Diffusion combustion burner mixing chamber 23 Diffusion combustion burner air hole 24 Gaseous fuel nozzle 30 Premix Combustion Burner 31 Mixing Chamber 32 Air Hole 33 Gaseous Fuel Injection Hole 34 Liquid Fuel Nozzle 35 Swirling Flow 36 Circulating Flow 40 Burner Cover 41 Burner Plate 42 Air Inlet 43 Air Introducing Portion 44 Guide Plate 45 Distribution Plate 46 Partition Plate 50 Combustion gas 100 Compressed air 101 Cooling air 102 Diffusion combustion air 103 Diffusion flame 104 Premixed combustion air 105 Premixed flame 201 Liquid fuel 202 Gaseous fuel

Claims (6)

A diffusion combustion burner located in the axial center of the combustor;
A plurality of premixed combustion burners disposed on the outer periphery of the diffusion combustion burner;
A mixing chamber inside the premixed combustion burner for mixing fuel and air;
An air flow path for imparting a swirl component to the air flowing into the mixing chamber;
A gas turbine comprising the diffusion combustion burner and the plurality of premixed combustion burners, and a burner cover having a plurality of air inlets for introducing air into the diffusion combustion burner and the plurality of premixed combustion burners In the combustor,
A gas turbine combustor characterized in that the circumferential position of the air inlet provided in the burner cover is opposed to the middle of two adjacent premixed combustion burners. The gas turbine combustor according to claim 1.
A gas turbine combustor, wherein a swirl component to be given to air flowing into the mixing chamber by the air flow path is determined by a positional relationship between the premixed combustion burner and the air inlet. The gas turbine combustor according to claim 2.
In the premixed combustion burner in which the air inlet is positioned clockwise with respect to the axial center of the combustor, the swirl component is clockwise with respect to the axial center of the combustor,
In the premixed combustion burner in which the air inlet is positioned counterclockwise with respect to the axial center of the combustor, the swirl component is counterclockwise with respect to the axial center of the combustor. Gas turbine combustor. The gas turbine combustor according to claim 1.
A guide plate formed to protrude to the inside of the burner cover at the edge of the air inlet;
A distribution plate formed on the side surface of the diffusion combustion burner so as to protrude toward the outer peripheral side of the combustor at a position facing the middle of the two adjacent premixed combustion burners. A gas turbine combustor. The gas turbine combustor according to claim 1.
A partition plate for connecting an inner wall of the burner cover and a side surface of the diffusion combustion burner so as to separate the adjacent premixed combustion burners;
The gas turbine combustor, wherein the air inlet is disposed at a circumferential position in contact with the partition plate in the burner cover. The gas turbine combustor according to claim 4 or 5,
A diffusion combustion burner mixing chamber for mixing fuel and air inside the diffusion combustion burner;
A plurality of regions formed on a side surface portion of the diffusion combustion burner divided by the distribution plate or the partition plate;
An air flow path for providing a swirl component to the air that is provided in each of the plurality of regions and flows into the diffusion combustion burner mixing chamber,
A gas turbine combustor characterized in that the opening area of the air flow path in each region of the side surface of the diffusion combustion burner is formed to be uniform.

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