JP3960166B2 - Gas turbine combustor and operation method of gas turbine combustor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a gas turbine combustor and a method for operating a gas turbine combustor.
[0002]
[Prior art]
In particular, the present invention relates to a low NOx type gas turbine combustor with low emission of nitrogen oxides, and JP-A-5-172331 is cited as a prior art.
[0003]
In a gas turbine combustor, a diffusion combustion system in which fuel is directly injected into a combustion chamber has been widely employed in order to ensure a large turndown ratio from startup to a rated load condition and to ensure a wide range of combustion stability. There are also premixed combustion systems.
[0004]
[Problems to be solved by the invention]
In the conventional example, the diffusion combustion method has a problem of high level NOx. In the case of the premixed combustion method, there are problems of combustion stability such as flashback and flame stabilization at start-up and partial load. In actual operation, it is desirable to solve these problems simultaneously.
[0005]
An object of the present invention is to provide a gas turbine combustor having low NOx and excellent combustion stability and a method for operating the gas turbine combustor.
[0006]
[Means for Solving the Problems]
In the gas turbine combustor of the present invention, a coaxial jet of a fuel jet and an air flow flowing on the outer peripheral side of the fuel jet is formed. gas A plurality of fuel nozzles for injecting fuel into the combustion chamber and a plurality of air holes for injecting air into the combustion chamber; gas A plate-like member having a plurality of air holes is arranged on the wall surface of the combustion chamber so that fuel and air are ejected into the combustion chamber, and the flow area of the air hole is equal to the flow path of the fuel ejection hole of the fuel nozzle. Formed larger than the area, from the upstream side of the disk-shaped member and the fuel nozzle gas The front end of the fuel nozzle is upstream of the wall surface of the combustion chamber and in the vicinity of the inlet of the air hole so that the fuel is premixed in the premixing flow path of the air hole and then rapidly mixed in the combustion chamber. From the fuel nozzle gas Fuel is ejected toward the air hole In addition, a plurality of the fuel nozzles and the plurality of air holes are formed as one module, and a part of the air holes among the air holes provided in the module with respect to a fuel jet axis of the fuel nozzle. Tilt about only It is characterized by that.
[0007]
Alternatively, the operation method of the gas turbine combustor according to the present invention includes a plate-like member having a plurality of air holes arranged on the wall surface of the combustion chamber, and the flow area of the air holes is determined by the fuel ejection of the fuel nozzle. Formed larger than the flow path area of the hole, upstream from the wall surface of the combustion chamber, and from the tip of the fuel nozzle disposed near the inlet of the air hole. gas The fuel is ejected toward the air hole to form a coaxial jet of the fuel jet and the air flow flowing on the outer peripheral side of the fuel jet, and from the upstream side of the disk-shaped member and the fuel nozzle gas The fuel is premixed in the premixing flow path of the air hole, and then the coaxial jet flows from the disk-shaped member. gas Fuel and air are jetted into the combustion chamber and rapidly mixed in the combustion chamber In addition, a plurality of the fuel nozzles and the plurality of air holes are formed as one module, and a part of the air holes among the air holes provided in the module with respect to a fuel jet axis of the fuel nozzle. The axis of the coaxial jet spouted from only is inclined It is characterized by that.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
First, two types of combustion methods in a gas turbine combustor will be described.
[0009]
(1) In the diffusion combustion system, as shown in FIG. 2, fuel is ejected outward near the outlet of the air swirler provided at the head of the combustor so as to intersect the swirling flow of air, and the central axis It aims to stabilize the diffusion flame by the circulation flow that can be made above.
[0010]
In FIG. 2, the air 50 sent from the compressor 10 passes between the outer cylinder 2 and the combustor liner 3, and a part of the combustion chamber 1 serves as cooling air 31 of the combustor liner and dilution air 32 that promotes mixing of the combustion gas. And part of the air flows into the combustion chamber 1 through the air swirler 12 as head swirling air 49. The gaseous fuel 16 is injected outward from the diffusion fuel nozzle 13 so as to intersect the swirling air flow, and forms a stable diffusion flame 4 together with the head swirling air 49 and the primary combustion air 33. The generated high-temperature combustion gas enters the turbine 18 and is exhausted with work.
[0011]
Although the diffusion combustion system shown here has high combustion stability, a flame is formed in a portion where the fuel and oxygen have a stoichiometric ratio, and the flame temperature becomes a high temperature close to the adiabatic flame temperature. Since the generation rate of nitrogen oxides increases exponentially with an increase in flame temperature, the diffusion concentration of nitrogen oxides is generally high in diffusion combustion, which is undesirable from the viewpoint of preventing air pollution.
[0012]
(2) On the other hand, the premixed combustion method is used for reducing NOx. FIG. 3 shows an example in which NOx is reduced by using diffusion combustion with excellent stability at the center and premixed combustion with excellent low NOx performance on the outer peripheral side. In FIG. 3, the air 50 sent from the compressor 10 passes between the outer cylinder 2 and the combustor liner 3, partly as the combustor liner cooling air 31 to the combustion chamber 1, and partly for premixed combustion. The air 48 flows into the premixer 23. The remainder flows into the combustion chamber 1 from the combustion air hole 14 and the cooling air hole 17 through a passage between the premixer flow path and the combustor end plate. The gaseous fuel 16 for diffusion combustion is injected from the diffusion fuel nozzle 13 into the combustion chamber 1 to form a stable diffusion flame 4. The premixed gaseous fuel 21 is ejected from the fuel nozzle 8 into the annular premixer 23 and mixed with air to form the premixed gas 22. The premixed gas 22 flows into the combustion chamber 1 to form a premixed flame 5. The generated high-temperature combustion gas enters the turbine 18 and is exhausted with work.
[0013]
However, when such a premixed combustion method is adopted, an unstable element peculiar to premixed combustion is included, such as a so-called flashback phenomenon in which a flame enters the premixer and burns out the structure. .
[0014]
In the embodiment of the present invention, the fuel jet and the combustion air flow path are arranged coaxially so that the fuel flow is a coaxial jet that wraps the air flow, and further, the fuel jet and the combustion air flow path are configured to be dispersed in a large number. It is arranged on the combustion chamber wall surface as a perforated coaxial jet. On the other hand, a part or all of the coaxial jets are configured to flow at an appropriate swirl angle around the combustor axis. In addition, the fuel supply system is divided into a plurality of parts, and the fuel is supplied to only a part of the system when the gas turbine is started and partially loaded.
[0015]
By making the fuel into a coaxial jet that envelops the airflow, the fuel flows into the combustion chamber and then mixes with the surrounding coaxial airflow before actually in contact with the hot gas and starting combustion. It burns after it becomes a premixed gas mixture. For this reason, low NOx combustion equivalent to lean premixed combustion becomes possible. At this time, the portion corresponding to the premixing tube of the conventional premixing combustor is extremely short, and the fuel concentration is almost zero in the vicinity of the wall surface, so the potential for burnout due to flashback is extremely low.
[0016]
In addition, recirculation for stabilizing the flame at the same time while forming a flow form of a coaxial jet by configuring it so that a part or all of the coaxial jet flows with an appropriate swirl angle around the axis of the combustor. A flow can be formed.
[0017]
In addition, when starting up gas turbines and under partial load operation, by supplying fuel to only some systems, the fuel is locally over-concentrated, and diffusion combustion that uses oxygen in the surrounding air Combustion stability can be ensured by burning in a form close to.
[0018]
(First embodiment)
A first embodiment of the present invention will be described below with reference to FIG. In FIG. 1, the compressor
The air 50 sent from 10 passes between the outer cylinder 2 and the combustor liner 3. That air
A part of 50 flows into the combustion chamber 1 as the cooling air 31 of the combustor liner 3. The remainder of the air 50 flows into the combustion chamber 1 through the air holes 52 as coaxial air 51.
[0019]
The fuel nozzle 55 and the fuel nozzle 56 are disposed so as to be coaxial or close to the same position as the injection hole of the combustion air hole 52, and the fuel 53 and the fuel 54 are substantially the same as the combustion air from the fuel nozzle 55 and the fuel nozzle 56. As a coaxial jet, it is ejected into the combustion chamber 1 to form a stable flame. The generated high-temperature combustion gas enters the turbine 18 to work and is exhausted.
[0020]
In the present embodiment, the fuel 53 and the fuel 54 are divided from a fuel supply system 80 having a control valve 80a. That is, here, the fuel supply system 80 is divided into two parts, a first fuel supply system 54b and a second fuel supply system 53b. The first fuel supply system 54b and the second fuel supply system 53b are respectively provided with a control valve 53a and a control valve 54a that can be individually controlled. The control valve 53a and the control valve 54a are configured such that each fuel flow rate is independently controlled by the load of the gas turbine. Here, the control valve 53a can control the flow rate of the fuel nozzle group 56, which is a central fuel nozzle group, and the control valve 54a can control the flow rate of the fuel nozzle 55 group, which is a surrounding fuel nozzle group. In the present embodiment, the fuel nozzle system is divided into a plurality of fuel nozzle groups in the central portion and the surrounding fuel nozzle groups, and a corresponding fuel supply system is provided, and the above-described control device capable of independently controlling the fuel flow rate is provided. .
[0021]
Next, details of the nozzle portion will be described with reference to FIG. In this embodiment, the fuel nozzle body is divided into a central fuel nozzle 56 and a surrounding fuel nozzle 55. Corresponding air holes 52 and air holes 57 are provided on the front side of the fuel nozzle 55 and the fuel nozzle 56 in the injection direction. A plurality of the air holes 52 and the air holes 57 are provided in a disk-like member with a small diameter. A plurality of air holes 52 and air holes 57 are provided so as to correspond to the plurality of fuel nozzles 55 and the fuel nozzles 56.
[0022]
The air hole 52 and the air hole 57 have a small diameter, but when the fuel injected from the fuel nozzle 55 and the fuel nozzle 56 passes through the air hole 52 and the air hole 57, a fuel jet is generated along with surrounding air. It is desirable to have such a size that an annular flow of air enclosing it is formed. For example, it is desirable that the jet diameter from the fuel nozzle 55 and the fuel nozzle 56 be slightly larger.
[0023]
The air hole 52 and the air hole 57 are arranged so as to form a coaxial jet with the fuel nozzle 55 and the fuel nozzle 56, and a large number of coaxial jets in which the fuel jet is wrapped in an air annular flow are formed in the air hole 52 and the air. It ejects from the end face of the hole 57. In other words, the fuel nozzle holes of the fuel nozzle 55 and the fuel nozzle 56 are installed at the same position as the air hole 52 and the air hole 57 in a coaxial or near-coaxial position, and the fuel jet flows toward the vicinity of the inlet center of the air hole 52 and the air hole 57. The annular flow of the jet and fuel jet and the air enclosing it is a coaxial jet.
[0024]
Since fuel and air are configured as a large number of small-diameter coaxial jets, these fuel and air can be mixed in a short distance. Therefore, high combustion efficiency can be maintained without uneven distribution of fuel.
[0025]
Further, in the configuration of the present embodiment, partial mixing proceeds until the fuel is ejected from the end face of the air hole, and mixing of fuel and air at a shorter distance can be expected. Furthermore, by adjusting the flow path length of the air hole, it is possible to set from a state of hardly mixing in the flow path to a state of almost complete premixing.
[0026]
In this embodiment, an appropriate swirl angle is given to the center fuel nozzle 56 and the center air hole 57 so as to swirl around the combustion chamber axis. Thus, by providing the corresponding air hole 57 with a swivel angle that gives a swirl component around the combustion chamber axis, a stable recirculation region by swirl is formed in the mixed airflow including the central fuel, and the flame is stabilized. Can do.
[0027]
In this embodiment, a remarkable effect can be expected for various load conditions of the gas turbine. The fuel flow rate is adjusted using the control valve 53a and the control valve 54a shown in FIG. 1 to cope with various load conditions of the gas turbine.
[0028]
In other words, under conditions where the gas turbine load is small, the fuel flow rate with respect to the total air amount is small. In this case, only the central fuel 53 is supplied, and the fuel concentration in the central region exceeds the concentration at which the flame is stably formed. It can be operated to keep. Also, under conditions with a large gas turbine load, both the central fuel 53 and the surrounding fuel 54 can be supplied to perform lean low NOx combustion as a whole. In an intermediate load, the amount of fuel 53 in the center is set such that the equivalent ratio exceeds 1 with respect to the amount of air flowing from the air holes 57, and the operation is performed in a diffusion combustion manner using ambient air for combustion. It is also possible.
[0029]
Therefore, it can contribute to flame stabilization and low NOx combustion according to various gas turbine loads.
[0030]
In this way, by making the fuel jet into a coaxial jet that envelops the air flow, the fuel flows into the combustion chamber and then mixes with the surrounding coaxial air flow before actually contacting the hot gas and starting combustion. Then, after it becomes a premixed gas with an appropriate mixing ratio, it burns. For this reason, low NOx combustion equivalent to lean premixed combustion becomes possible. At this time, in this embodiment, the portion corresponding to the premixing tube of the conventional premixing combustor can be made extremely short.
[0031]
Moreover, since the fuel concentration is almost zero near the wall surface, the potential for burnout due to flashback is extremely low.
[0032]
As described above, according to the present embodiment, it is possible to provide a gas turbine combustor and a gas turbine combustor operating method that have low NOx and excellent combustion stability.
[0033]
(Second embodiment)
FIG. 5 shows details of the nozzle portion of the second embodiment. In this embodiment, there is one fuel system and it is not divided into the center and the periphery. Further, the swivel angle is not given to the nozzle and the combustion air hole near the center. In this embodiment, the nozzle structure can be simplified in operation or in a situation where combustion stability is not a significant problem due to the properties of the fuel.
[0034]
(Third embodiment)
FIG. 6 shows a third embodiment. In this embodiment, a single combustor is configured by combining a plurality of nozzles of the second embodiment shown in FIG. That is, a single combustor is configured by combining a plurality of fuel nozzles and air holes as one module.
[0035]
By adopting such a configuration, as described in the first embodiment, a plurality of fuel systems can be used to flexibly cope with a change in the load of the gas turbine. Those having different capacities can be provided relatively easily.
[0036]
(Fourth embodiment)
FIG. 7 shows a fourth embodiment. This embodiment is basically the same as the second embodiment, but differs in that the swirl component is given to the coaxial jet itself by the air swirler 58.
[0037]
With this configuration, mixing of individual coaxial jets is promoted, and more uniform low NOx combustion is possible. A structure in which a swirl component is given to the fuel jet in the fuel nozzle is also effective for promoting mixing.
[0038]
(Fifth embodiment)
FIG. 8 shows a fifth embodiment. This embodiment is different from the third embodiment in that the nozzle installed on the central axis is a conventional diffusion burner 61 having an air swirler 63 and a fuel injection hole 62 intersecting with the air swirler 63.
[0039]
Such a configuration is considered advantageous when starting stability is emphasized by using a conventional diffusion combustion burner at start-up / acceleration and partial load.
[0040]
(Sixth embodiment)
FIG. 9 shows a sixth embodiment. In this embodiment, a liquid fuel nozzle 68 and an atomizing air nozzle 69 are installed in the diffusion burner 61 of the embodiment shown in FIG.
66 is atomized with the atomizing air 65 so as to cope with the combustion of the liquid fuel. Although many cannot be expected in terms of reducing NOx, it is intended to provide a combustor that can flexibly cope with fuel supply conditions.
[0041]
(Seventh embodiment)
FIG. 10 shows a seventh embodiment. This embodiment is an example in which an auxiliary fuel supply system 71, a header 72, and a nozzle 73 are added to the downstream side of the combustor in the first embodiment shown in FIGS. The fuel ejected from the nozzle 73 flows into the combustion chamber as a coaxial jet through the air hole 74, and the combustion reaction proceeds by the high-temperature gas flowing from the upstream side.
[0042]
By adopting such a configuration, the structure is complicated, but a low NOx combustor that is flexible in load handling can be provided.
[0043]
(Eighth embodiment)
FIG. 11 shows an eighth embodiment. In this embodiment, the individual fuel nozzles of the embodiment shown in FIG. 5 are made into a double structure so that the liquid fuel 66 is supplied to the inner liquid fuel nozzle 68 and the atomized air 65 is supplied to the outer nozzle 81. Liquid fuel by supplying
Even when 66 is used, a large number of coaxial jets can be formed to achieve low NOx combustion with a very low backfire potential.
[0044]
In addition, by stopping the supply of liquid fuel and supplying gaseous fuel instead of atomizing air, it is possible to operate as a low-NOx combustor of gaseous fuel, and combustion corresponding to both liquid and gaseous fuel It can also have features that make it possible to provide vessels.
[0045]
As described above, a part or all of the fuel nozzles have a double structure so that the spraying of the liquid fuel and the gaseous fuel can be switched or used in combination, so that both liquid and gaseous fuels can be used.
[0046]
As described above, according to the above-described embodiment, the fuel is flowed into the combustion chamber by making many coaxial jets that wrap the fuel in the air flow, and then actually comes into contact with the hot gas and starts combustion. Before mixing, it is mixed with the surrounding coaxial air flow, and after it becomes a premixed gas with an appropriate mixing ratio, it burns. For this reason, low NOx combustion equivalent to lean premixed combustion becomes possible. At this time, the part corresponding to the premixing tube of the conventional premixing combustor is extremely short, and the fuel concentration is almost zero near the wall surface. it can.
[0047]
(Ninth embodiment)
FIG. 12 shows a partial cross-sectional view in which the fuel nozzle 55 and the combustion air hole 52 are arranged substantially coaxially. A combustion air hole 52 is provided on the fuel ejection downstream side of the fuel nozzle 55. That is, a premixing channel is formed on the fuel jet downstream side of the fuel nozzle 55. The size (flow path area) of the combustion air hole 52 is preferably larger than the fuel ejection hole area of the fuel nozzle 55. In the present embodiment, the diameter of the combustion air hole 52 (the premixed channel diameter area) is formed larger than the diameter (area) of the fuel injection hole of the fuel nozzle 55. The fuel is ejected from the fuel nozzle 55 through this premixing flow path, and the fuel and air are coaxially jetted. At this time, it is desirable that the fuel from the fuel nozzle 55 be ejected toward substantially the center of the inlet portion of the combustion air hole 52 to form a good coaxial jet. In the case of the present embodiment, the fuel concentration distribution downstream of the air outlet has a symmetrical shape around the axis of the coaxial flow as shown in the figure, and rapidly mixes and becomes uniform as it goes downstream. As a result, compared with the conventional premixed combustion method, the same low NOx performance can be realized with a short premix distance.
[0048]
FIGS. 13A and 13B are examples in which the axis of the combustion air hole 52 is inclined with respect to the fuel jet axis of the fuel nozzle 55 by an angle θ °. In the vicinity of the entrance of the combustion air hole 52, the combustion air hole 52 is inclined with respect to the flow direction in a coaxial arrangement. In this arrangement, the fuel concentration distribution downstream of the air outlet is asymmetric with respect to the air jet axis as shown in the figure. As it goes downstream, it is mixed and uniformed, but the asymmetry with respect to the axis is not completely eliminated, and it is considered that a concentration deviation remains. Then, for example, as shown in FIG. 13B, such a misalignment between the fuel jet axis and the air hole axis is positively utilized for the coaxial nozzle hole near the center of the burner formed by the coaxial jet assembly. It is possible. That is, in this embodiment, the above-described inclination of the combustion air hole 52 is provided around the flame holding region and near the center of the burner, and the combustion air hole 52 on the opposite side is not inclined (θ = 0 °). The fuel concentration in the flame holding region can be kept relatively high, and the flame stability can be enhanced. In this embodiment, while adopting a straight fuel injection hole with no turning angle or inward / outward angle in the fuel injection hole, only the air hole has an angle not parallel to the axis of the burner, such as the turning angle, It is excellent in that the premixed gas can be swirled and inward and outward angles can be given with a relatively simple structure, and the premixed gas flow can be set with a relatively simple structure according to the burner configuration and purpose. ing.
[0049]
Next, FIG. 14 is an example in which the axial direction of the coaxial arrangement of the fuel injection hole and the air hole is the same and the positional deviation d is set intentionally. Due to this deviation, as shown in the figure, the concentration deviation is asymmetrically distributed with respect to the air jet axis, and the concentration deviation of the fuel can be positively generated, and combustion characteristics such as combustion stability can be improved. Can do.
[0050]
In this embodiment, the fuel from the fuel nozzle 55 flows almost along the center of the premixing channel in the premixing channel. Further, air is configured to flow from the outer peripheral side of the fuel nozzle 55 along the outer peripheral side of the flow channel in the premixed flow channel. Therefore, in the premixing channel, air flows along the fuel flow on the outer peripheral side of the fuel flow, and both flows are substantially coaxial. By providing a plurality of such nozzle forms, mixing can be promoted and stable combustion can be realized with a simple structure.
[0051]
15A and 15B show examples of the length of the premixing length L. Mixing by rapid expansion after exiting the air hole is dominant, and the premixing length L is low in mixing uniformity.
The impact on NOx performance is considered not so great. As shown in FIG. 15A, it is considered that the low NOx performance can be sufficiently ensured even if the member for forming the air hole is made thin and the premixing distance L is shortened. On the other hand, it is possible to expect savings in the material of the member forming the air holes and the processing cost of the hole processing of the air holes, and the cost reduction is advantageous. FIG. 15B shows an example where the premix length L is sufficiently long. Fuel and air can be expected to be sufficiently mixed in this flow path, and a combustor with even lower NOx properties can be provided. Furthermore, it is advantageous that L is about several times the diameter of the air hole in order to add a swirl component by giving an oblique angle to the air hole or to give an inward / outward deflection angle. is there.
[0052]
FIGS. 15C and 15D show examples in which the axial distance G between the fuel nozzle tip and the air hole inlet is different. FIG. 15C is an example in which G is large. A substantial premixing distance can be taken, and it is considered advantageous for uniform mixing and low NOx properties. Further, since the length of the fuel nozzle can be shortened, the manufacturability of the fuel nozzle is improved and the cost can be reduced. On the other hand, FIG. 15 (d) shows an arrangement in which a premixing channel is formed relatively downstream of the fuel nozzle 55, the axial distance G is negative, and the fuel injection hole protrudes into the air hole. With such an arrangement, the potential of flashback is further reduced, and it is considered effective when, for example, ignitable fuel such as dimethyl ether (DME) is burned with low NOx.
[0053]
FIGS. 15E and 15F show an example in which the diameter D of the air hole is small and large. In the case of FIG. 15 (e) in which the diameter D of the air hole is small and the number thereof is increased, the fuel and air are finely dispersed from the burner, so that they are uniformly mixed well in a short distance, and are lower. Suitable when NOx performance is important. When the air hole diameter D is increased and the number of air holes is reduced as shown in FIG. 15 (f), a long mixing distance is required and the uniformity is somewhat impaired, so the low NOx performance is slightly inferior. It is possible to reduce the number of manufacturing steps and to make the required manufacturing accuracy relatively rough, which is advantageous when emphasizing cost reduction.
[0054]
(Tenth embodiment)
FIG. 16A shows another embodiment. In the embodiment described so far, the arrangement of the coaxial air holes in the burner surface has been shown as being concentrically distributed, but the basic characteristics are not lost even in a lattice arrangement or a staggered arrangement. Absent. FIG. 16 (a) shows an example of such arrangement. When arranged in this manner, although depending on the average flow velocity in the combustor liner, the axial position in which the flame is formed becomes a substantially lifted flame within the liner cross section. It may be simple to produce but may not be sufficient in terms of flame stabilization. In FIG. 16B, in such a case, a part of the burner surface is provided with a region having a small air hole area or a region having no air hole or a large pitch even though the air hole pitch is the same. In this example, a low flow velocity portion and a circulation flow region are formed, and the flame is stabilized at this portion. Such a configuration can provide a combustor having a low flashback potential and having both low NOx properties and combustion stability.
[0055]
(Eleventh embodiment)
FIG. 17 shows an example of an experimental result regarding the relationship between the premix distance L and the NOx emission amount of the present invention. Complete premix combustion, in which fuel and air are completely mixed and then combusted, requires a mixing device having a sufficiently long mixing distance or a large pressure loss, but the NOx discharged is very low. (Point A in the figure) On the other hand, in a practical premixer structure formed by arranging a plurality of fuel nozzles in an annular premixing flow path, NOx increases approximately in inverse proportion to the premixing distance L. An example of a premixer, NOx, is shown at point B in the figure.
[0056]
On the other hand, in the present invention, the relationship between the premix distance and the NOx emission amount in one embodiment of the present invention in which fuel and air are arranged as a large number of coaxial jets is as shown at point C in the figure. However, it has been shown that the NOx performance equivalent to that of the conventional premixer is exhibited at a premixing distance of 1/20 or less that of the conventional structure.
[0057]
【The invention's effect】
According to the present invention, it is possible to provide a gas turbine combustor having low NOx and excellent combustion stability and a method for operating the gas turbine combustor.
[Brief description of the drawings]
FIG. 1 is an explanatory view including an overall cross-sectional view of a first embodiment of the present invention.
FIG. 2 is an explanatory diagram of a diffusion combustion system.
FIG. 3 is an explanatory diagram of a premixed combustion method.
FIG. 4 is a detailed explanatory view of a nozzle part according to the first embodiment of the present invention.
FIG. 5 is a detailed explanatory view of a nozzle part according to a second embodiment of the present invention.
FIG. 6 is a detailed explanatory view of a nozzle part according to a third embodiment of the present invention.
FIG. 7 is a detailed explanatory view of a nozzle part according to a fourth embodiment of the present invention.
FIG. 8 is a detailed explanatory view of a nozzle part according to a fifth embodiment of the present invention.
FIG. 9 is a detailed explanatory view of a nozzle portion according to a sixth embodiment of the present invention.
FIG. 10 is a detailed explanatory view of a nozzle part according to a seventh embodiment of the present invention.
FIG. 11 is a detailed explanatory view of a nozzle portion according to an eighth embodiment of the present invention.
FIG. 12 is a detailed explanatory view of a nozzle part according to a ninth embodiment of the present invention.
FIG. 13 is a detailed explanatory view of another nozzle portion of the ninth embodiment of the present invention.
FIG. 14 is a detailed explanatory view of another nozzle portion of the ninth embodiment of the present invention.
FIG. 15 is a diagram showing various nozzle configurations of the present invention.
FIG. 16 is a detailed explanatory view of a nozzle portion according to a tenth embodiment of the present invention.
FIG. 17 is a diagram showing the relationship between the premixing distance and the NOx emission amount.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Combustion chamber, 2 ... Outer cylinder, 3 ... Combustor liner, 4 ... Diffusion flame, 5 ... Premix flame, 8, 55, 56 ... Fuel nozzle, 10 ... Compressor, 12, 63 ... Air swirler, 13 DESCRIPTION OF SYMBOLS ... Diffusion fuel nozzle, 14 ... Combustion air hole, 16 ... Gas fuel, 17 ... Cooling air hole, 18 ... Turbine, 21 ... Premixed gas fuel, 22 ... Premixed gas, 23 ... Premixer, 31 ... Cooling air 32 ... dilution air, 33 ... primary combustion air, 49 ... head swirling air,
50 ... Air, 51 ... Coaxial air, 52, 57, 74 ... Air hole, 53, 54 ... Fuel, 61 ... Diffusion burner, 62 ... Fuel injection hole, 65 ... Spraying air, 66 ... Liquid fuel, 68 ... Liquid fuel nozzle 69 ... Spray air nozzles, 71, 80 ... Fuel supply system, 72 ... Header, 73 ... Nozzle.

Claims (6)

A plurality of fuel nozzles for injecting gaseous fuel into the combustion chamber and a plurality of air holes for injecting air into the combustion chamber so that a coaxial jet of the fuel jet and the airflow flowing on the outer peripheral side of the fuel jet is formed; And place
A disk-shaped member having a plurality of air holes is arranged on the wall surface of the combustion chamber so that the gaseous fuel and air of the coaxial jet flow are ejected into the combustion chamber.
The flow area of the air hole is formed larger than the flow area of the fuel ejection hole of the fuel nozzle,
So that the air on the upstream side of the disk-shaped member and the gaseous fuel from the fuel nozzle are premixed in the premixing flow path of the air hole and then rapidly mixed in the combustion chamber.
The tip of the fuel nozzle is disposed in the upstream of the wall surface of the combustion chamber and in the vicinity of the inlet of the air hole,
While ejecting gaseous fuel from the fuel nozzle toward the air hole ,
A plurality of the fuel nozzles and a plurality of the air holes are formed as one module, and only a part of the air holes among the air holes provided in the module with respect to the fuel jet shaft of the fuel nozzle. A gas turbine combustor characterized by tilting an axis . The gas turbine combustor according to claim 1.
A gas turbine combustor comprising a control device that divides a large number of fuel nozzles into a plurality of fuel supply systems and independently controls each fuel flow rate according to a load of the gas turbine. The gas turbine combustor according to claim 1.
A gas turbine combustor comprising a mechanism for imparting a swirl component around each axis to each air hole or fuel nozzle. The gas turbine combustor according to claim 1.
A gas turbine combustor characterized in that a part or all of the fuel nozzle has a double structure so that spraying of liquid fuel and gaseous fuel can be switched or used together. An operation method of a gas turbine combustor in which a plurality of fuel nozzles for ejecting gaseous fuel into a combustion chamber and a plurality of air holes for ejecting air into the combustion chamber are arranged,
A disc-like member having a plurality of air holes arranged on the wall surface of the combustion chamber;
The flow area of the air hole is formed larger than the flow area of the fuel ejection hole of the fuel nozzle,
A upstream of the wall surface of the combustion chamber, the gaseous fuel from the tip of the fuel nozzle that is disposed on the vicinity of the inlet of the air hole ejected toward the air hole, the outer peripheral side of the fuel jet and the fuel jet Forming a coaxial jet with the airflow flowing through the pre-mixing of the air upstream of the disk-shaped member and the gaseous fuel from the fuel nozzle in the premixing flow path of the air hole,
The coaxial fuel jet gas fuel and air are jetted from the disk-shaped member into the combustion chamber, and are rapidly mixed in the combustion chamber .
A plurality of the fuel nozzles and a plurality of the air holes are formed as one module, and only a part of the air holes among the air holes provided in the module with respect to the fuel jet axis of the fuel nozzle. A method of operating a gas turbine combustor, characterized in that an axis of a jet of coaxial jet is inclined . A method for operating a gas turbine combustor according to claim 5 ,
A method of operating a gas turbine combustor, wherein the fuel nozzle is divided into a plurality of fuel supply systems, and each fuel flow rate is independently controlled by a gas turbine load.

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