JPH0814565A - Gas turbine combustor - Google Patents

Abstract

(57) [Summary] [Object] The present invention relates to a gas turbine combustor, and an object thereof is to provide a combustion method structure with less NOx production. A diffusion-premix combustion pilot burner 500 having a first fuel nozzle 103 for injecting two-stage diffusion fuel into the end axis of an inner cylinder 101, and double swirlers 108, 109 for flowing a premix air is provided. A plurality of second premix burners 502 are provided on the outer circumference thereof, and a plurality of third premix burners 503 are further provided on the outer circumference thereof. The exit end of the premix burner protrudes longer into the combustion chamber 211 toward the outer circumference, and the number of fuel supply premix burners is controlled from the shaft center to the outer circumference according to the output. [Effect] As a result, the combustion efficiency is high in the entire operating range, and 99.5% of the total fuel can be burned in lean premixed combustion, so that NOx production can be greatly reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas turbine combustor, and more particularly to a gas turbine combustor suitable for reducing NOx by performing lean premixed combustion.

[0002]

2. Description of the Related Art An example of a gas turbine combustor mainly composed of lean premixed combustion is disclosed in Japanese Utility Model Laid-Open No. 2-100060, in which a diffusion combustor arranged in the inner cylinder axial center portion is stable in combustion. Function to increase Further, a lean fuel premixed gas is swirlingly supplied from each of the premixing chambers of the multiple annular premixing combustor arranged on the outer peripheral side thereof, and burns while being assisted by diffusion combustion.

[0003]

In this case, when only the vicinity of the center is burning, the flame is cooled by the air from the outer periphery, so that a part of the fuel is discharged unburned or a toxic one is discharged. A large amount of carbon oxide is emitted.

The object of the present invention is to increase the combustion efficiency even in the state where a portion is combusted, reduce the diffusion combustion ratio that produces a large amount of NOx, increase the premixed combustion ratio that produces a small amount of NOx, and at the same time, premix this mixture. A gas turbine combustion apparatus capable of stable combustion even when the fuel concentration is low and capable of low NOx combustion in a wide load range.

[0005]

A first feature of a gas turbine combustor according to the present invention for achieving the above object is to arrange a gas turbine combustor in an axial center portion of a combustion chamber and inject fuel to perform diffusion combustion. A diffusion combustor and an outer peripheral side of the diffusion combustor are arranged to eject a mixture of air and fuel for premixed combustion.
A plurality of first premixed combustors formed so that their air-fuel mixture outlet ends project downstream from the fuel outlet end of the diffusion combustor, and more than the air-fuel mixture outlet ends of the first premixed combustor. , A plurality of second air-fuel mixture outlet ends formed to project downstream
And the first premixing combustor and the second premixing combustor are alternately arranged in the circumferential direction on the outer peripheral side of the diffusion combustor.

A second feature of the present invention is that the above-mentioned first feature.
The premixing combustor is provided with a swirler for swirling the mixture at the outlet of the mixture.

The third feature is that the axial center portion of the combustor is arranged,
A tubular first fuel nozzle having an inlet end and a discharge end;
A tubular tubular member that is coaxial with the fuel nozzle, is located on the outer periphery of the first fuel nozzle, has a first swirler at the inlet end, and has a discharge end substantially flush with the discharge end of the first fuel nozzle. 1 air supply pipe, coaxial with the first fuel nozzle, located on the outer circumference of the first air supply pipe, and a first swirler on the same plane as the discharge end of the first air supply pipe A tubular second air feed pipe having an annular second swirler that swirls in the same direction, a combustion chamber formed by rapidly expanding a downstream portion of a discharge end of the second air feed pipe, and the first fuel. A plurality of first fuel injection holes radially oriented with respect to the axis at the discharge end of the nozzle and directed in the downstream direction; and a first swirler of the first air feed pipe and a discharge end located intermediate the first swirler. The diffusion combustor has a plurality of second fuel injection holes that are inclined toward the discharge end from the side surface of the fuel nozzle toward the inner wall of the first air supply pipe.

A fourth feature of the present invention is that, in the above diffusion combustor, the inlet ends of the first air feed pipe and the second air feed pipe are branched from the same air pipe line, A second upstream side having one or more nozzles for injecting fuel to be mixed with the air supplied to the first air feeding pipe and the second air feeding pipe.
A fuel nozzle is added and the diffusion-premix combustor is controlled to independently control the fuel supplied to the first fuel nozzle and the fuel supplied to the second fuel nozzle.

Further, a fifth feature of the present invention is to arrange a plurality of the above diffusion-premix combustors in parallel to form a combustion chamber with one chamber downstream from the discharge end of the second air feed pipe, A gas turbine combustor that controls the number of diffusion-premixed combustors operating in response to a gas turbine load.

Further, a sixth feature of the present invention is that the means for supplying air to the means for supplying air to the vicinity of the fuel outlet of the diffusion combustor is provided with a means for mixing the fuel and air near the fuel outlet of the diffusion combustor. It is configured to supply energy. That is, the fuel of the diffusion combustor and the above air-fuel mixture are mixed to form a flame in the center of the combustor.

Furthermore, the structure of the gas turbine having the first characteristic may be provided with a means for supplying an air-fuel mixture in the vicinity of the fuel outlet of the diffusion combustor having the third characteristic.

Furthermore, a seventh feature of the present invention is that the means for supplying the air-fuel mixture to the vicinity of the fuel outlet of the diffusion combustor having the above-mentioned third feature, that is, the air-fuel mixture outlet end of the pre-mixture injection nozzle, A first swirler for swirling the mixture and the first swirler
A second swirler positioned on the outer peripheral side of the swirler, and the swirling directions of the air-fuel mixture ejected from the first and second swirlers are the same.
Than the flow rate of the air-fuel mixture ejected from the swirler of
The first and second swirlers are configured so that the flow rate of the air-fuel mixture ejected from the swirler is increased.

Furthermore, an eighth feature of the present invention is that, in a structure in which air is circulated between the outer cylinder and the inner cylinder to cool the combustor, the combustor is ejected from the premix combustor. This is because the air-fuel mixture outlet end of the premix combustor is formed so that the outflow direction of the air-fuel mixture toward the axial center of the inner cylinder.

The structure having the fifth characteristic may be applied to any of the structures having the first to fourth characteristics described above.

Furthermore, a ninth feature of the present invention is to have an outer cylinder and an inner cylinder that forms a combustion chamber provided inside thereof.
In the one configured to circulate the air between the outer cylinder and the inner cylinder to cool the combustor, it is arranged on the outer peripheral side of the diffusion combustor and ejects a mixture of air and fuel to premix it. A plurality of first premixing combustors formed so that the air-fuel mixture outlet end of the diffusion combustor projects downstream from the fuel outlet end of the diffusion combustor, and mixing of the first premixing combustor. Between the plurality of second premixing combustors whose mixture gas outlet ends project toward the downstream side of the gas outlet ends, and between the diffusion combustor and the first and second premixing combustors. A premixed gas jet nozzle for supplying a mixture of air and fuel is provided in the vicinity of the fuel outlet of the diffusion combustor provided in, and the first premixed combustor and the second premixed combustor are On the outer peripheral side of the diffusion combustor, they are alternately arranged in the circumferential direction, and the inner cylinder or the tail cylinder is further arranged. Lies in the provision of the air flow control valve for controlling the air flow hole for guiding the air flowing between the outer cylinder and the inner cylinder into the combustion chamber, the flow rate of air flowing through the air flow hole.

Furthermore, a tenth feature of the present invention is a diffusion combustor which is installed at the axial center of a combustion chamber of a gas turbine combustor and injects fuel for diffusion combustion, and an outer peripheral side of the diffusion combustor. A plurality of first premixing combustors disposed in the air-fuel mixture and performing premixed combustion by injecting a mixture of air and fuel, and a mixture mixture outlet end of the first premixer combustor rather than the mixture mixture outlet end thereof. Of a plurality of second premixed combustors formed so as to project downstream and a fuel outlet of the diffusion combustor provided between the diffusion combustor and the first and second premixed combustors A premixed gas injection nozzle for supplying a mixture of air and fuel is provided in the vicinity, and the first premixed combustor and the second premixed combustor are provided in the circumferential direction on the outer peripheral side of the diffusion combustor. Alternately, and as the load on the gas turbine increases, the premixed gas injection nozzles Et al., The first premixed combustors, second
It is configured to increase the flow rate of the air-fuel mixture by injecting fuel in the order of the premix combustor.

[0017]

According to the first aspect of the present invention described above, the mixture gas outlet end of the first premixing combustor is formed so as to project downstream of the fuel outlet end of the diffusion combustor, and the second premixing combustor is formed. The air-fuel mixture outlet end of the premixed combustor is formed so as to project downstream of the air-fuel mixture outlet end of the first premixed combustor, and the first and second premixed combustors are connected to the diffusion combustor. Since they are alternately arranged on the outer peripheral side in the circumferential direction, the diffusion combustion flame of the diffusion combustor comes to be ignited in the order of the first premixing combustor and the second premixing combustor. Since the ignition performance of the reactor is improved and the interference between the diffusion combustion flame and the premixed combustion flame can be suppressed, the diffusion combustion flame can maintain stable combustion, and the premixed combustion flame can diffuse. Since it is less affected by the high temperature flame of the combustion flame, lean combustion is performed Generate can utilize the characteristics of the premixed combustors of suppressing.

According to the second aspect of the present invention described above,
Since the swirling can be given to the mixture, the stability of the premixed combustion flame is improved.

According to the third aspect of the present invention described above, when the fuel flow rate is reduced, the fuel is diffused and burned while being mixed only with the air supplied from the first air supply pipe, but the first fuel nozzle has the first fuel nozzle. The fuel injected from the fuel injection port is flame-retained by the secondary flow of air formed by the discharge end of the first fuel nozzle, and the fuel injected from the second fuel injection port provided on the side surface of the first fuel nozzle is the first fuel. The fuel concentration in the flame-holding region theoretically is the easiest to burn because it flows along the outer wall surface of the nozzle and partially mixed with air into the flame-holding region of the fuel injected from the first fuel injection port. The fuel concentration becomes closer, and the stability of the diffusion flame is improved.

Further, according to the fourth aspect of the present invention, since the air-fuel mixture is supplied from the first air supply pipe and the second air supply pipe, the diffusion flame near the axis of the combustion chamber has combustion stability. Since the amount of heat required for combustion stability can be supplied at the contact surface with the air-fuel mixture flowing from the second swirler, the diffusion-premix combustor as a whole can be stably combusted. Further, in this configuration, the diffusion fuel and the premixed fuel can be controlled independently, so that the diffusion fuel is reduced and diffusion combustion is performed in the mixture gas supplied from the first air feed pipe on the outer periphery thereof, and the mixture gas is also large. By premixing and burning the part, the amount of heat necessary for stable combustion of the air-fuel mixture supplied from the second air supply pipe on the outer periphery of the part can be generated, so that NOx generation is small and combustion stability is improved. High combustion is possible.

Further, according to the fifth feature of the present invention, NO
Since the number of combustors that operate a diffusion-premix combustor with low x production and high combustion stability according to the gas turbine load is controlled, it is possible to operate with less NOx production in a wide load range of the gas turbine. is there.

Further, according to the sixth feature of the present invention,
Since the air-fuel mixture is supplied to the vicinity of the fuel outlet of the diffusion combustor, the diffusion fuel is mixed with the air-fuel mixture and burned, so that the stability of the diffusion combustion flame is significantly improved. That is, in the present invention, the diffusion combustor is configured so that the diffusion combustion flame is formed in the central portion of the combustion chamber by the diffusion fuel and the air-fuel mixture, instead of the conventional diffusion combustor that performs the diffusion combustion only with the diffusion fuel. is there.

Furthermore, according to the seventh aspect of the present invention, the first aspect is provided in which the mixture gas is swirled at the mixer outlet end of the premixture injection nozzle for supplying the mixture gas to the vicinity of the fuel outlet of the diffusion combustor. And a second swivel located on the outer peripheral side of the first swivel
And the swirl direction of the air-fuel mixture jetted from the first and second swirlers is in the same direction, and the flow rate of the air-fuel mixture jetted from the first swirler is Also, since the first and second swirlers are configured so that the flow rate of the air-fuel mixture ejected from the second swirler increases, the fuel is injected from the diffusion fuel nozzle provided in the axial center of the combustion chamber. The diffused fuel is mixed with the air-fuel mixture flowing out from the first swirler to form a more easily combustible air-fuel mixture,
The diffusion combustion flame can be stabilized. At this time, the first
If the air-fuel mixture flowing out from the swirler is too large, the effect of raising the combustion temperature during combustion by the air-fuel mixture alone will decrease even if the diffused fuel is injected, and the effect of stabilizing the combustion flame will decrease. The air-fuel mixture is discharged to the second swirler on the outer peripheral side of the first swirler. That is, the swirling directions of the air-fuel mixture ejected from the first and second swirlers are the same, and the second swirling is performed more than the flow rate of the air-fuel mixture ejected from the first swirler. By configuring so that the flow rate of the air-fuel mixture ejected from the vessel is increased, the air-fuel mixture that is more than necessary to stabilize the diffusion combustion flame described above is passed through the second swirler to approximately the center of the diffusion combustion flame. Is supplied to the section, and reacts with the diffusion combustion flame without impairing the stability of the diffusion combustion flame. Furthermore, by using a fuel-air premixture for the diffusion combustion air,
Even if the amount of fuel injected from the diffusion fuel nozzle provided at the shaft center is small, it is possible to perform stable combustion and achieve low NOx.

Furthermore, according to the eighth aspect of the present invention, the outflow direction of the air-fuel mixture ejected from the premix combustor is
Since the air-fuel mixture outlet end of the premix combustor is formed toward the axial center of the inner cylinder, the premix combustion flame is not cooled by the cooling air flowing near the side surface of the inner cylinder. It is possible to suppress a decrease in the combustion temperature of the flame, and it is possible to suppress the discharge of unburned components.

Furthermore, according to the ninth feature of the present invention, an air flow hole is provided in the transition piece or the inner tube and the flow rate of the air flowing into the combustion chamber from this air flow hole is controlled. The flow rate of the supplied air can be reduced, the concentration of the fuel-air premixture can be kept constant, and high efficiency and low NOx combustion can be achieved.

Further, according to the tenth feature of the present invention, the premixed gas jet nozzle, the first premixed combustor, the second
Since it is possible to increase the fuel supply amount without significantly changing the mixing ratio of each of the premixed combustors of
The stability of the premixed combustion flame can be further improved.

[0027]

EXAMPLE An example of a gas turbine combustor according to the present invention will be described with reference to FIGS.

FIG. 1 is a vertical sectional view of a gas turbine combustor of this embodiment. The outer shape of the combustor is formed by a cylindrical outer cylinder 102 that is a pressure vessel that houses the entire combustor, and the inner cylinder 10 that forms a combustion chamber 211 inside the outer cylinder 102.
A first fuel nozzle 103, which is a diffusion fuel nozzle for injecting diffusion fuel, is provided at the center of the end of the combustion chamber 211 formed by the inner cylinder 101.

The characteristic structure of this embodiment of the combustor having the above structure will be described below.

An annular swirler 108, which is a first swirler for imparting a swirl to the air supplied to the vicinity of the fuel outlet of the first fuel nozzle 103 on the outer periphery of the first fuel nozzle 103, and an outer periphery of this swirler 108. , A swirler 109 that is a second swirler is provided, and these swirlers 108 and 109 are further provided.
Second fuel nozzle 1 for mixing fuel with air discharged from the
11, the second fuel nozzle 111 and the swirlers 108, 10
And a first premixing chamber 206 between the first and the second mixing chambers 9 and 9. Further, the swirlers 108 and 109 are configured so that the swirling directions of the air-fuel mixture flowing out from the swirlers 108 and 109 are the same. Then, the swirlers 108 and 109 are configured such that the flow rate of the air-fuel mixture flowing out from the swirler 109 is larger than the flow rate of the air-fuel mixture flowing out from the swirler 108. Swirler 1
The outflow area of 09 may be made larger than the outflow area of the swirler 108.

The swirled air-fuel mixture flowing out from the swirler 108 mixes with the fuel ejected from the first fuel nozzle 103 to form a diffusion combustion flame. This mixture should be supplied as much as the diffusion combustion flame is stable,
If a large amount of a lean air-fuel mixture is supplied to the root of a combustion flame in which the combustion reaction of fuel and air has not progressed yet, the diffusion combustion flame becomes unstable, and the unburned component increases due to the decrease in flame temperature and There is a risk of lowering. Therefore, an excessive amount of air-fuel mixture for stabilizing the diffusion flame is allowed to flow out from the swirler 109. The air-fuel mixture flowing out from the swirler 109 is supplied to the central portion of the combustion flame in which the combustion reaction of the fuel and air has progressed to a certain extent or the reaction has almost ended, or to the wake side. In order to supply the excessive air-fuel mixture to the central portion of the combustion flame or to the wake side, the air-fuel mixture outlet end of the swirler 109 is formed so as to project downstream from the air-fuel mixture outlet end of the swirler 108. Is also good.

Further, on the outer circumference of the premixed gas jet nozzle,
A second premixing chamber 205, a third fuel nozzle 104 at the center of the end of the second premixing chamber 205, a first premixing combustor including an air supply swirler 113 and an air hole 120 on the outer periphery thereof, and The air-fuel mixture outlet end of the first premixing combustor is formed so as to project downstream from the air-fuel mixture outlet end.
A second premix combustor including a third premix chamber 207, a fourth fuel nozzle 105 at the center of the end of the third premix chamber 207, and a swirler 110 for air supply around the third premix chamber is provided. Further, a swirler 107 that swirls the premixed air is provided at the air-fuel mixture outlet end of the first premixed combustor to promote the mixing of fuel and air and stabilize the premixed combustion flame.

The second premixing chamber 20 is provided in the first premixing combustor.
5, the air rectifying chamber 210 to be supplied to the
And an air flow control valve 1 for controlling the area of the air inlet 209
06, the second premixing combustor is provided with a swirler 110 for supplying air around the outer periphery thereof, and a flow diverter plate 112 for determining the air-fuel mixture outlet flow path direction of the third premixing chamber 207. The distribution plate 112 directs the air-fuel mixture toward the center of the combustion chamber so that the combustion flame of the second premixing combustor is not cooled by the air flowing through the annular passage 208 formed by the inner cylinder 101 and the outer cylinder 102. To In particular, the effect is great for the one that cools the film by flowing air on the inner surface of the inner cylinder 101. Further, since the inner cylinder 101 and the premixed flame do not come into contact with each other, the metal temperature of the inner cylinder 101 can be lowered. The first premixed combustor and the second premixed combustor are alternately arranged circumferentially on the outer peripheral side of the diffusion combustor as shown in FIG. By arranging the first and second premixed combustors in this way, the diffusion flame of the diffusion combustor is ignited in the order of the first premixed combustor and the second premixed combustor, The ignition performance of the premixed combustor is improved, the interference between the diffusion combustion flame and the premixed combustion flame is reduced, the diffusion combustion flame can maintain stable combustion, and the premixed combustion flame is diffused combustion. Since it is less likely to be affected by the high temperature flame of the flame, lean combustion is performed to reduce NO.
The characteristic of the premixed combustor that suppresses the generation of x can be utilized. Further, the first premix combustor and the second premix combustor do not have to be arranged on the same circumference. It is preferable that the second premixed combustor is arranged slightly outside the circumference where the first premixed combustor is arranged.

Next, a fuel and air control method applied to the gas turbine combustor according to the present invention will be described with reference to FIGS. 3 and 4.

First, the fuel and air supply system will be described with reference to FIG.

Combustion air supplied from the compressor has an annular passage 2 formed by the inner cylinder 101 and the outer cylinder 102.
The gas is supplied to the combustion chamber 211 through the first premixing chamber 206, the second premixing chamber 205, and the third premixing chamber 207 after branching in the middle in the direction of arrow 212 in 08. The air supplied to the second premixing chamber 205 is decelerated in the air rectifying chamber 210 and then flows into the second premixing chamber 205 after the air flow rate is controlled by the flow rate control valve 106 provided at the air inlet 209. On the other hand, the fuel for the first fuel nozzle 103 is pipe 2
01 and a flow rate control valve (not shown), the fuel for the second fuel nozzle 111 is supplied via a pipe 202 and a flow rate control valve (not shown), and the fuel for the third fuel nozzle 104 and a flow rate control valve (not shown) 203. Supplied through a valve,
The fuel for the fourth fuel nozzle 105 is supplied through the pipe 204 and a flow control valve (not shown). Starting ignition with an output of 0% or less is possible by supplying fuel from the first fuel nozzle 103 of the diffusion combustor, but it is also possible to use fuel supply from the second fuel nozzle 111 together. Further, when flame propagation to the adjacent combustor is required at the time of start-up ignition, a flame propagation tube communicating with the adjacent inner tube is provided in the inner tube 101 near the outlet of the second premixer 205, and the vicinity of the flame propagation tube is provided. The flame can be propagated by supplying the fuel to the third fuel nozzle 104 which supplies the fuel to the second premixer 205. When the flame propagation is completed, the fuel supply to the third fuel nozzle is stopped, the fuel is supplied to the first fuel nozzle 103 and the second fuel nozzle 111, and the operation is performed up to the output of 0%. Even when the fuel is supplied only to the first fuel nozzle, the operation can be performed up to the output of 0%. Figure 3 shows the fuel distribution corresponding to the output of 0% or more.
The air distribution is shown in FIG.

In FIG. 3, the horizontal axis is the output of the gas turbine and the vertical axis is the fuel flow rate.

The output from 0% to a% is the first of the diffusion combustor.
Fuel P-1 is supplied from the fuel nozzle 103, and the combustion chamber 21
Burn within 1. In the range of output a% to b%, the fuel P-2 from the second fuel nozzle 111 is added. From the output b% to d%, the fuel M− from the third fuel nozzle 104 is further added.
Add 1. The fourth fuel nozzle 1 is further used when the output is d% or more.
Add fuel M-2 from 05.

From the output 0% to a%, the first fuel nozzle 1
It is also possible to operate by supplying the fuel P-1 from No. 03 and the fuel P-2 from the second fuel nozzle 111.

In the air distribution of FIG. 4, the air flowing into the combustion chamber 211 from the swirlers 108 and 109 near the axial center of the inner cylinder 101 is indicated by P, and the second premixing chamber 205 to the combustion chamber 211 is indicated.
The air flowing into the combustion chamber 211 is indicated by M-1, and the air flowing into the combustion chamber 211 from the third premixing chamber 207 is indicated by M-2.
The wall cooling air of 01 is indicated by C. When the output is less than b%, combustion occurs only in the inner cylinder axial center portion, and the fuel P-1 from the first fuel nozzle 103 and the fuel P-2 from the second fuel nozzle 111.
Is increased, the air flow control valve 106 is operated in the closing direction to decrease the air M-1 flowing to the second premixer 205 and increase the air P flowing to the first premix chamber 206.
Low NOx, high efficiency combustion. Then, at the output b%, the fuel P-1 from the first fuel nozzle 103 is decreased, the fuel M-1 from the third fuel nozzle 104 is increased, and the fuel P-1 flowing from the second premixing chamber 205 into the combustion chamber 211 is increased. The amount of air-fuel mixture is reduced and the fuel concentration is increased to facilitate combustion. The fuel M-1 supplied to the second premixing chamber 205 is increased in the range of the output b% to c%, but it is necessary to supply the lean fuel premixed mixture to the combustion chamber 211 in order to suppress the generated NOx. Yes, air M supplied to the second premix chamber 205
-1 is increased by operating the air flow control valve 106 in the opening direction. When the output is c% or more, the concentration of the fuel-air premixture supplied from the second premixing chamber 205 to the combustion chamber 211 becomes high, and stable combustion can be performed without controlling the air flow rate. However, since the NOx generation amount increases as the premixed gas concentration increases, the second premixing chamber 20 is output when the output d% or more.
The fuel M-1 supplied to No. 5 is kept constant, and the third premixing chamber 20
The fuel M-2 supplied to No. 7 is increased. When the amount of fuel M-2 is small, the concentration of the premixed gas fuel supplied from the third premixing chamber 207 to the combustion chamber 211 is low, but the third premixing chamber 207
The premixed gas is transferred to the combustion chamber 2 by the deflector plate 112 provided at the outlet of the
11, the premixed gas supplied from the upstream first premixing chamber 206 and the second premixing chamber 205 to the combustion chamber 211 is mixed with the burned combustion gas and burned.

When the fuel pipe 203 to the third fuel nozzle 104 of the present invention is made into two systems and each is provided with a fuel flow rate control valve, the air M− supplied to the second premixing chamber 205 at the output b% in FIG. Second premixing chamber 20 without decreasing 1
It is possible to maintain the concentration of the premixture supplied from a part of No. 5 to the combustion chamber 211 at a combustible concentration, and it is possible to perform combustion while preventing a significant decrease in combustion efficiency. In this case, only air is supplied to the remaining second premixing chamber.
Then, when the output further increases and falls between b% and d%,
If fuel is also supplied to the remaining second premixing chamber 205, highly efficient combustion is possible.

Next, another embodiment of the present invention will be described with reference to FIG.

The difference from FIG. 1 is that the inner cylinder 101 and the outer cylinder 10 are different from each other.
Air circulation hole 213 for guiding the air flowing in the annular passage 208 formed by 2 to the combustion chamber 211, and the air circulation hole 2
13 is that an air flow rate control valve 115 that controls the flow rate of air flowing into the combustion chamber 211 from the side wall 13 is provided on the side wall surface of the transition piece 114.

A fuel control method using the configuration shown in FIG. 5 will be described with reference to FIG.

When the air flow control valve 115 is operated in the opening direction, the air flowing into the combustion chamber 211 is uniformly reduced. The fuel flow rate distribution with respect to the gas turbine output is shown in FIG. When the output is 0% or less, only the fuel P-1 from the first fuel nozzle 103 is operated, and when the output is 0% to b%, the fuel P-2 from the second fuel nozzle 111 and the fuel from the third fuel nozzle 104 are operated. Add M-1 and burn at the same time. When the output is b% or more, the fuel M-2 from the fourth fuel nozzle 105 is further added.

A method of controlling the air when using the configuration shown in FIG. 5 will be described with reference to FIG.

When the output is 0%, the first
Fuel P-2, M- to the premix chamber 206 and the second premix chamber 205
Air flow control valve 11 for supplying 1 to perform highly efficient combustion
5 is operated in the opening direction to maximize the air B flowing from the air inlet 213 into the transition piece 114. The air flow rate control valve 115 is operated in the closing direction to increase the air supplied to the combustion chamber 211 in proportion to the increase in the fuel until the output reaches a%, and the air B is made zero. When the output is a% or more, the fuel-air premixture from the first premix chamber 206 and the second premix chamber 205 burns with high efficiency without controlling the air flow rate. When the output is b% or more, the fuel M-2 is also supplied to the third premix chamber 207.

As another modification of the present invention, although not shown, an air passage for releasing air to the outside of the system is provided in the outer cylinder of the combustor section, and an air flow control valve is provided in the middle of this passage. The fuel flow rate distribution and the air flow rate distribution for the gas turbine output are the same as those in FIGS. 6 and 7.

Another embodiment of the present invention will be described with reference to FIGS.

In FIG. 8, the third premixing chamber 207 is provided with the inner cylinder 1
01 and the outer cylinder 102 are provided in an annular passage 208, and the outlet end is provided on the wall surface of the inner cylinder 101. The control of fuel and air in this case is the same as in FIGS. 3 and 4.

Next, it corresponds to the first fuel nozzle 103 and the swirlers 108 and 109 in FIG.

An embodiment of the pilot burner of the gas turbine combustor will be described with reference to FIG.

FIG. 10 is a longitudinal sectional view of the gas turbine combustor pilot burner of this embodiment. The outer shape of the pilot burner is a cylindrical inner cylinder 101 forming a combustion chamber 211.
And a second air feed pipe 121 on the upstream side of the second air feed pipe 121, and an annular second swirler (second swirler) 109 is provided in the vicinity of the discharge end of the second air feed pipe 121. The cylinder is provided with a first air supply pipe 129. A first swirler 108 that swirls in the same direction as the second swirler 109 is provided at the inlet end of the first air supply pipe 129, and a first fuel nozzle that injects diffused fuel at the axial center that is the inner periphery thereof. 103 is provided. A second fuel nozzle 111 having a plurality of branch pipes 151 is provided in an annular first premixing chamber 206 formed by the first fuel nozzle 103 and the second air supply pipe 121. The first fuel nozzle 103 has a flow control valve 15
A pipe 201 for fuel supply having 2 is connected.
A pipe 202 for fuel supply having a flow rate control valve 153 is connected to the second fuel nozzle 111.

The characteristic construction of this embodiment of the pilot burner having the above construction will be described below.

The discharge end 154 of the first fuel nozzle 103 is provided with a plurality of first fuel injection holes 155 facing the downstream direction and having an angle of less than 90 degrees with respect to the axis, and the gaseous fuel is radiated radially. Is jetted. The discharge end 154 of the first fuel nozzle 103 may have a flat surface as well as the truncated cone shape shown in the drawing. On the side surface of the first fuel nozzle 103, a plurality of second fuel injection holes 156 inclined toward the discharge end side are provided so that the fuel flows along the wall surface of the first fuel nozzle 103 when the gas fuel injection speed is low. , Its position is to supply the air or the air-fuel mixture to the annular passage 125 on the outer periphery thereof, and to provide the swirling flow, and the first swirler 108 and the first air supply pipe 129.
Is the middle of the discharge end. A swirl is given to the outer circumference of these gaseous fuels by the first swirler 108, and there is a first swirling airflow flowing through the annular passage 125, and a second swirl is given to the outer circumference of the gas swirl on the outer circumference.
There is a swirling air flow. By the first swirling airflow,
A small circulation flow 131 is formed near the discharge end 154 of the first fuel nozzle 103, and a slightly larger circulation flow 132 is formed downstream thereof. In addition, the second swirling airflow causes a larger circulation flow 1 downstream of the circulation flow 132.
33 is formed. When the straight pipe portion 128 is provided downstream of the annular second swirler 109 provided in the second air supply pipe 121, the circulation flow 133 is formed further downstream. When the gaseous fuel is injected from the first fuel nozzle 103 to the above-mentioned air flow, when the fuel flow rate is large,
A part of the fuel injected from the fuel injection port 155 diffuses in the air supplied from the first swirler 108, and the circulating flow 13
The second swirler 10 holds the remaining fuel by flame holding
9 is diffused in the air supplied from 9 and is stably burned by the circulating flow 133. On the other hand, the fuel injected from the second fuel injection port 156 collides with the inner wall of the first air supply pipe 129, and
Partly premixed with the air supplied from the swirler 108 of
The circulating stream 132 will be formed with a partial premixture. When the fuel flow rate is small, the fuel injected from the first fuel injection port 155 diffuses only in the air supplied from the first swirler 108, and the flame is held by the circulation flow 132. On the other hand, the fuel injected from the second fuel injection port 156 is injected into the annular passage 125 of the air supplied from the first swirler 108, and the injection flow velocity is slow, so that the first air supply pipe 1
Since they do not reach the inner wall of 29 and gather on the center side, the fuel concentration of the circulation flow 132 becomes high and combustion becomes easy. Further, when the fuel flow rate is low, when the fuel injected from the first fuel injection port 155 diffuses into the air circulation flow 132,
Since the fuel concentration becomes too low, it tries to burn inside the circulation flow 131, but since the circulation flow 131 is small, it penetrates to the outside of the circulation flow 131 even if the fuel injection flow velocity from the first fuel injection port 155 becomes slow. , Difficult to form a small flame. On the other hand, since the second fuel injection port 156 has a small injection port diameter and is inclined in the discharge end direction, when the fuel injection flow velocity becomes slow, the fuel flows along the wall surface of the first fuel nozzle 103, Since it flows into the circulation flow 131, stable combustion becomes possible by mixing with a part of the fuel injected from the first fuel injection port 155. The first swirler 108 is preferably a radial flow type, but can also function as an axial flow type.

Next, the case where the diffusion combustion and the premixed combustor are simultaneously performed will be described. Fuel F ₁ from the first fuel nozzle 103
Of the second fuel nozzle 111, the fuel F ₂ is injected from the third fuel injection port 151 provided in the plurality of branch pipes 151 of the second fuel nozzle 111, and the fuel F ₂ is supplied to the first swirler 108 and the second swirler 109. Mix with the entire air to form a mixture. The air supplied from the first swirler 108 becomes an air-fuel mixture, and the fuel F ₁ injected from the first fuel injection port 155 and the second injection port 156 of the first fuel nozzle 103 is easily combusted. Stable combustion is possible with less fuel F ₁ than in the case of diffusion combustion alone.
1, a ring-shaped flame is formed. This flame serves as an overall ignition source, the premixed gas supplied from the first swirler 108 burns in the circulation flow 132, and the flame formed by these two circulation flows is emitted from the second swirler 109 on the outer periphery thereof. It serves as an ignition source for the supplied premixed air, which is stably combusted in the circulation flow 133, and the whole is combusted. This effect is remarkable when the lean premixed gas, which is difficult to perform stable combustion by the premixed combustion alone, is burned. As a result, the proportion of the fuel F ₁ forming the diffusion flame can be reduced to 2% or less of the total fuel, and NOx production can be greatly suppressed. In particular, there is a straight pipe portion 128 on the downstream side of the second swirler 109, and the circulation flow 133 is the circulation flow 133.
When it is formed on the downstream side of the fuel cell 2, the circulation flows 131 and 132 are stably formed, and the combustion stability is improved.
₁ can be reduced.

At this time, the premixed gas swirl flow from the first swirler 108, which serves as the ignition source of the premixed gas swirl flow from the second swirler 109, has its function even if the amount of heat generated by combustion is small. Therefore, the passage area of the first swirler 108 may be smaller than the passage area of the second swirler 109.

Next, an embodiment of the gas turbine combustor using the pilot burner shown in FIG. 10 will be described. FIG. 11 is a vertical sectional view of an embodiment of the present invention. Arrange the pilot burner 500 shown in FIG. 10 on the axis of the combustion chamber 211,
On the outer periphery of the pilot burner 500, a plurality of main burners 501 of the same type as the pilot burner 500 are arranged in parallel. The outlet ends of these burners are substantially flush with each other, and the combustion chamber 211 is a common space formed by the inner cylinder 101. The inner cylinder 101, the pilot burner 500, and the plurality of main burners 501 are housed in the outer cylinder 102 which is a pressure vessel.

The air supplied from the compressor (not shown) is
Annular passage 2 formed by outer cylinder 102 and inner cylinder 101
08 in the direction of arrow 250 to cool the inner cylinder 101 midway. And part of the pilot burner 500 has an axial center.
Of the plurality of main burners 501 into the second air supply pipe 121 of the plurality of main burners 501, and from the cooling holes (not shown) on the upstream end face of the remaining combustion chambers 211 to the combustion chambers. It flows into 211.

Next, fuel control from starting ignition to 100% load will be described below. In the structure of FIG. 2, since each burner is independent and it is difficult to transfer the fire to the adjacent burner during operation, at the time of start-up ignition, the diffusion combustion fuel is simultaneously injected from the first fuel nozzle 103 of the pilot burner 500. The diffusion combustion fuel is also injected from the first fuel nozzles 401 of the plurality of main burners 501, and diffusion combustion is performed by all the burners. Next, the second pilot burner 500
The gas turbine low load region is operated by injecting the premixed fuel from the fuel nozzle 111 and simultaneously performing the diffusion combustion and the premixed combustion. When the gas turbine load increases, the number of premix combustion operations in which fuel is injected from the second fuel nozzle 411 of the main burner 501 sequentially increases, and the gas turbine load 100
%, All the main burners 501 simultaneously perform diffusion combustion and premixed combustion. At this time, the diffusion combustion fuel is about 2% of the total fuel of the combustor, and the remaining about 98% is the premixed combustor with a low combustion flame temperature, so that the operation with less NOx production is possible.

When the outlet average gas temperature of the combustion chamber 211 is sufficiently higher than the spontaneous ignition temperature of the fuel used, the fuel-air mixture is supplied from the injection port having no flame holding function to the combustion chamber 211.
Since it is possible to combust by injecting into the inside, a part of the plurality of main burners 501 has a structure without the first fuel nozzle 401 for injecting diffusion fuel, the fuel supply system 405, and the fuel control valve 404. It is possible.

Next, another embodiment of the gas turbine combustor using the pilot burner shown in FIG. 10 will be described. 12 is a vertical sectional view of another embodiment of the present invention, and FIG. 13 is a lateral sectional view of another embodiment of the present invention as seen from the downstream side. An inner cylinder 101 forming a combustion chamber 211, a first fuel nozzle 103 for supplying diffused fuel at an end axis of the inner cylinder 101, a first swirler 108 and a second swirler 109 for supplying air around the inner cylinder 101. A pilot burner 500 including a second air supply pipe 121 forming an annular first premixing chamber 206 and a second fuel nozzle 111 for supplying premixed fuel to the air.
A second premixing chamber 205 on the outer periphery thereof, a third fuel nozzle 104 at the end center of the second premixing chamber 205, a third swirler 221 and an air hole 222 for air supply on the outer periphery thereof.
Of the fourth swirler 107, which swirls the air-fuel mixture in the vicinity of the outlet of the second premixing chamber 205, and the air rectifying chamber 210 of the air supplied to the second premixing chamber 205, its air inlet 209, and the air inlet 209. The flow rate control valve 106 for controlling the area and the third premixing chamber 207 protruding to an intermediate portion of the combustion chamber 211.
A fourth fuel nozzle 105 at the center of the end thereof, a fifth swirler 110 for supplying air around the outer periphery of the fourth fuel nozzle 105, and a deflector plate for determining the flow direction of the air-fuel mixture provided at the outlet end of the third premixing chamber 207. 112 and an outer cylinder 1 which is a pressure container for housing these
02 and a pipe 2 for supplying fuel to the first fuel nozzle 103
01, its flow control valve 152, and the second fuel nozzle 11
No. 1 pipe 202 for supplying fuel and its flow control valve 15
3, Pipe 203 for supplying fuel to the third fuel nozzle 104
The flow rate control valve 213, the pipe 204 for supplying the fuel to the fourth fuel nozzle 105, and the flow rate control valve 237 constitute the entire combustor.

Combustion air supplied from a compressor (not shown) proceeds in the direction of arrow 250 in the annular passage 208 formed by the inner cylinder 101 and the outer cylinder 102, and in the middle, cools the inner cylinder 101 and parts. After being branched as leak air at the insertion portion, it is supplied to the combustion chamber 211 through the annular first premix chamber 206, second premix chamber 205, and third premix chamber 207. The air supplied to the second premixing chamber 205 is once decelerated in the rectifying chamber 210 after the air flow rate is controlled by the flow rate control valve 106 provided at the air inlet 209, and then flows into the second premixing chamber 205 from the air hole 120. To do. FIG.
In the structure of No. 2, it is possible to operate without providing the air flow control valve 106.

Next, fuel control from starting ignition to 100% load will be described below. For start-up ignition, fuel is supplied from the first fuel nozzle 103 of the pilot burner 500,
Ignition is performed by applying energy necessary for ignition by an ignition device (not shown). At this time, the second fuel nozzle 1
It is also possible to simultaneously supply premixed combustion fuel from 11 for ignition. Further, when flame propagation to the adjacent combustor is required at the time of start-up ignition, a flame propagation pipe communicating with the adjacent inner cylinder is provided at a position near the outlet end of the second premixing chamber 205 of the inner cylinder 101, By supplying fuel to the pilot burner 500 and also supplying fuel to the third fuel nozzle 104 that supplies fuel to the second premix chamber 205 near the flame propagation tube, ignition and flame propagation are possible. afterwards,
Combustion of part of the pilot burner and the second premixing burner 502 is continued until the gas turbine load is 0%, and the pilot burner is operated by combustion alone from the middle.

In the low load range of the gas turbine, the combustion of the pilot burner alone changes to the state of supplying fuel to the third fuel nozzle 104 and simultaneously burning the second premix burner 502. At this time, a plurality of second premix burners 502
Is divided into two groups, each of which has an independent fuel supply pipe 2
03, burning only one group first, then 2
By controlling the fuel so that the groups are burned, it is possible to perform an operation in which the combustion efficiency is significantly reduced and NOx production is prevented from increasing.

Next, in the medium load range of the gas turbine, the pilot burner 500 and the second premix burner 502 burn,
When the outlet average gas temperature of the combustion chamber 211 reaches a temperature sufficiently higher than the self-ignition temperature of the supplied fuel, for example, about 1200 ° C. in the case of methane gas, the fourth fuel nozzle is operated in order to operate under a higher gas turbine load. Fuel is supplied from 105, mixed with air flowing in from the fifth swirler 110 in the third premixing chamber 207, and then injected into the combustion chamber 211, self-ignited and burned.

In the combustor shown in FIG. 12, the pilot burner 50 is used.
The fuel burned at 0 is 25% or less of the total fuel of the combustor, and the diffusion combustion fuel supplied from the first fuel nozzle 103 is about 2% of the fuel burned at the pilot burner 500. The proportion of combustion fuel is 0.5% or less. Therefore, since the lean premixed combustion with less NOx production is 99.5% or more of the whole, NOx production can be significantly suppressed.

A system diagram of a gas turbine steam turbine combined power generation plant to which the present invention is applied is shown in FIG.
The air from the compressor 301 is guided to the combustor 303, fuel is supplied to generate high temperature combustion gas with a low NOx concentration, and the turbine 302 is expanded to perform work, and the work is taken out as an output of the generator 304. . The combustion exhaust gas that has worked is guided to the exhaust heat recovery boiler 307. Normally, the NOx concentration is reduced by the denitration device 308 therein,
When the present invention is applied, a denitration device becomes unnecessary. The exhaust heat recovery boiler 307 generates steam, guides the steam to the steam turbine 305 to perform work, and the work is performed by the generator 304.
As the output of.

[0069]

According to the present invention, it is possible to ignite the fuel-lean premixture on the outer periphery and to burn the fuel-lean premixture on the outer periphery by an extremely small amount of diffusion combustion.
Since the combustion is mainly premixed combustion with less Ox production, NOx production can be greatly reduced.

Further, by composing one combustor by assembling a plurality of the above combustors, it is possible to bypass the air that is not involved in combustion when the load is low, so that the combustion efficiency is always high and NOx is high. Operation with significantly reduced production is possible.

Further, by constructing one combustor by adding the structure in which the above-mentioned combustor is used as an ignition source for overall combustion as a pilot burner and injecting a lean fuel premixture from a downstream position of its outer periphery, at the time of low output Since the air that is not involved in combustion mixes with the combustion gas that has completed combustion, combustion efficiency is always high. Moreover, since the diffusion combustion ratio is very small, NOx production can be further reduced significantly. Due to the reduction of NOx, the denitration device provided in the exhaust duct or in the middle of the exhaust heat recovery boiler becomes unnecessary.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a gas turbine combustor according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a gas turbine combustor according to an embodiment of the present invention.

FIG. 3 is a diagram showing an example of a fuel control method when a gas turbine combustor according to the present invention is implemented.

FIG. 4 is a diagram showing an example of an air flow rate control method when a gas turbine combustor according to the present invention is implemented.

FIG. 5 is a vertical cross-sectional view of a gas turbine combustor according to another embodiment of the present invention.

FIG. 6 is a diagram showing an example of a fuel control method when a gas turbine combustor according to another embodiment of the present invention is implemented.

FIG. 7 is a diagram showing an example of an air flow rate control method when implementing a gas turbine combustor according to another embodiment of the present invention.

FIG. 8 is a vertical cross-sectional view of a gas turbine combustor according to another embodiment of the present invention.

FIG. 9 is a cross-sectional view of a gas turbine combustor according to another embodiment of the present invention.

FIG. 10 is a vertical sectional view of another embodiment of the present invention.

FIG. 11 is a vertical cross-sectional view of one embodiment of a combustor using another embodiment of the present invention.

FIG. 12 is a vertical cross-sectional view of another embodiment of a combustor using another embodiment of the present invention.

FIG. 13 is a cross-sectional view of another embodiment of a combustor using one embodiment of the present invention.

FIG. 14 is a system diagram of a combined power generation plant to which the gas turbine combustor according to the present invention is applied.

[Explanation of symbols]

101 ... Inner cylinder, 103 ... First fuel nozzle, 104 ... Third
Fuel nozzle, 105 ... Fourth fuel nozzle, 106 ... Air flow control valve, 107, 108, 109, 110, 113 ...
Swirler, 111 ... Second fuel nozzle, 205 ... Second premix chamber, 206 ... First premix chamber, 207 ... Third premix chamber,
211 ... Combustion chamber.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuhiro Iwai 502 Jinritsucho, Tsuchiura-shi, Ibaraki Machinery Research Institute, Hiritsu Manufacturing Co., Ltd. (72) Inventor, Yoichi Yoshinaga, 502 Kintatemachi, Tsuchiura City, Ibaraki Prefecture.

Claims (10)

[Claims] 1. A diffusion combustor which is arranged at the axial center of a combustion chamber and injects fuel to perform diffusion combustion; and a diffusion combustor which is arranged on the outer peripheral side of the diffusion combustor and ejects a mixture of air and fuel. Premixed combustion is performed, and a plurality of first air-fuel mixture outlets are formed so that their air-fuel mixture outlet ends project downstream from the fuel outlet end of the diffusion combustor.
Of the premixed combustor and a plurality of second premixed combustors formed such that the mixture mixture outlet end thereof projects downstream from the mixture mixture outlet end of the first premixed combustor. A gas turbine combustor in which the first premixed combustor and the second premixed combustor are alternately arranged circumferentially on the outer peripheral side of the diffusion combustor. 2. The gas turbine combustor according to claim 1, wherein a swirler for swirling the mixture is provided in the vicinity of the mixture outlet of the first premixing combustor. Turbine combustor. 3. A tubular first fuel nozzle, which is disposed at the axial center of the combustor and has an inlet end and a discharge end, and which is coaxial with the first fuel nozzle and is located on the outer periphery of the first fuel nozzle. A first air supply pipe having a first swirler at the inlet end, the discharge end of which is substantially flush with the discharge end of the first fuel nozzle, and coaxial with the first fuel nozzle, A tubular second air feed located on the outer periphery of the first air feed pipe and having an annular second swirler that swivels in the same direction as the first swirler on the same plane as the discharge end of the first air feed pipe. A supply pipe, a combustion chamber formed by abruptly expanding the downstream portion of the discharge end of the second air feed pipe, and a discharge end of the first fuel nozzle, which is directed toward a downstream direction that is radial with respect to the axis. A plurality of the first fuel injection ports and the first swirler of the first air supply pipe and the discharge end, and the first air supply pipe is provided from a side surface of the first fuel nozzle. Toward the inner wall of the tube, and the diffusion combustor having a plurality of second fuel injection port which is inclined discharge end. 4. The diffusion combustor according to claim 1, wherein the inlet ends of the first air feed pipe and the second air feed pipe are branched from the same air pipe line, and the first air supply pipe is provided upstream of the branched portion. A second fuel nozzle having one or more nozzles for injecting fuel for mixing with air supplied to the air supply pipe and the second air supply pipe,
A diffusion-premix combustor for independently controlling the fuel supplied to the first fuel nozzle and the fuel supplied to the second fuel nozzle. 5. A plurality of diffusion-premixing combustors according to claim 2 are arranged in parallel, and a combustion chamber is formed by making one chamber downstream from the discharge end of the second air feed pipe to cope with a gas turbine load. A gas turbine combustor that controls the number of diffusion-premix combustors that operate in unison. 6. A diffusion combustor which is arranged at an axial center of a combustion chamber and injects fuel to perform diffusion combustion, air supply means for supplying air to the vicinity of a fuel outlet of the diffusion combustor, and the diffusion combustion. A gas turbine combustor disposed on the outer peripheral side of the combustor, comprising a premix combustor for injecting a mixture of fuel and air to perform premix combustion, a fuel supply means for supplying fuel to the air supply means. And a premixture of air and fuel is supplied near the fuel outlet of the diffusion combustor. 7. A diffusion combustor which is arranged at the axial center of a combustion chamber and injects fuel to perform diffusion combustion, and a diffusion combustor which is arranged on the outer peripheral side of the diffusion combustor and ejects a mixture of fuel and air. In a gas turbine combustor comprising a premixed combustor for premixed combustion, an annular premixed gas jetting a mixture of fuel and air between the diffusion combustor and the premixed combustor. A jet nozzle is installed, and a first swirler that swirls the mixture and a second swirler located on the outer peripheral side of the first swirler are provided at the mixture outlet end of the premixed gas jet nozzle. The first and second swirlers are arranged so that the swirling directions of the air-fuel mixture ejected from the first and second swirlers are the same, and the flow rate of the air-fuel mixture ejected from the first swirler is higher than the flow rate of the air-fuel mixture. In order to increase the flow rate of the air-fuel mixture ejected from the second swirler, A gas turbine combustor characterized by comprising a swirler of the above. 8. An outer cylinder forming the outer shape of a combustor, an inner cylinder installed inside the outer cylinder and forming a combustion chamber, and an inner cylinder installed in the axial center portion of the inner cylinder for injecting fuel. The outer cylinder and the inner cylinder are provided with a diffusion combustor that performs diffusion combustion, and a premixing combustor that is disposed on the outer peripheral side of the diffusion combustor and ejects a mixture of fuel and air to perform premixing combustion. In a gas turbine combustor configured to circulate air between and to cool the combustor, the outflow direction of the air-fuel mixture ejected from the premix combustor is
A gas turbine combustor, wherein an air-fuel mixture outlet end of the premix combustor is formed so as to face an axial center portion of the inner cylinder. 9. An outer cylinder forming an outer shape of a combustor, an inner cylinder installed inside the outer cylinder to form a combustion chamber, and an inner cylinder connected to the inner cylinder to gas combustion gas from the combustion chamber. A gas turbine combustor having a transition piece that leads to a turbine and configured to cool the combustor by circulating air between the outer cylinder and the inner cylinder. A diffusion combustor which is installed and performs a diffuse combustion by injecting fuel, and a mixture of air and fuel which is arranged on the outer peripheral side of the diffusion combustor and ejects a premixed combustion to perform a premixed combustion A plurality of first premixing combustors formed so that the air-fuel mixture outlet end projects downstream from the outlet end, and the air-fuel mixture outlet end of the first premixing combustor,
A plurality of second premixed combustors whose mixture air outlet ends are formed to project downstream, and the diffusion provided between the diffusion combustor and the first and second premixed combustors. A premixed gas injection nozzle for supplying a mixture of air and fuel is provided in the vicinity of the fuel outlet of the combustor, and the first premixed combustor and the second premixed combustor are provided around the diffusion combustor. On the side, and arranged alternately in the circumferential direction, and in the inner cylinder or the transition piece, air circulation holes for guiding air flowing between the outer cylinder and the inner cylinder to the combustion chamber, and the air circulation holes. A gas turbine combustor comprising an air flow rate control valve for controlling a flow rate of air flowing through the gas turbine combustor. 10. A diffusion combustor installed in the axial center of a combustion chamber of a gas turbine combustor for injecting fuel to perform diffusion combustion,
A plurality of first premixed combustors arranged on the outer peripheral side of the diffusion combustor for ejecting a mixture of air and fuel to perform premixed combustion; and an air-fuel mixture outlet end of the first premixed combustor In addition, a plurality of second air-fuel mixture outlet ends formed so as to project downstream
Premix combustor, said diffusion combustor and said first and second
A premixed gas injection nozzle for supplying a mixture of air and fuel to the vicinity of the fuel outlet of the diffusion combustor provided between the first premixed combustor and the second premixed combustor. The premix combustors are alternately arranged in the circumferential direction on the outer peripheral side of the diffusion combustor, and as the load on the gas turbine increases, the first premix combustor ejects from the premix gas jet nozzle. A gas turbine combustor characterized in that the combustor and the second premixed combustor are injected in this order to increase the flow rate of the air-fuel mixture.