JP5372815B2 - Gas turbine combustor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem in a combustor reversing a flow of air at the upstream of a combustion chamber, sending it into an air nozzle, and jetting it out into the combustion chamber wherein since the flow of air is reversed at the upstream of the combustion chamber, a stagnation area of air is caused in an outer peripheral side of the combustor, it becomes difficult to send air into the air nozzle disposed in the outer peripheral side, deviation of fuel concentration is caused in the combustion chamber, and there is a possibility of increase of NOx. <P>SOLUTION: The combustor has the combustion chamber burning fuel and air, and a combustor liner forming the combustion chamber; a fuel nozzle jetting out fuel, and the air nozzle jetting out air, are disposed at the upstream of the combustion chamber; and air is passed from a downstream side of the combustion chamber through an outer side of the combustor liner, a direction of the flow is reversed in the upstream side of the combustion chamber, sent into the air nozzle, and jetted out into the combustion chamber. An inlet part of the air nozzle disposed in a radial outer side of the combustor is disposed downstream from an inlet part of an air nozzle disposed in an axial center side of the combustor. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to the structure of a gas turbine combustor.

  Gas turbine combustors include diffusion combustion and premixed combustion. In the diffusion combustion method, the fuel is directly injected into the combustion chamber in order to ensure a wide range of combustion stability with a large turndown ratio from start-up to rated load conditions. On the other hand, the premixed combustion method is a combustion method in which fuel and air are mixed in advance and supplied to the combustion chamber in order to reduce nitrogen oxides (NOx). The premixed combustion system has problems such as the occurrence of a flashback phenomenon in which a flame flows backward in the premixer and burns the structure.

  In order to solve this problem, Patent Document 1 discloses a combustor in which a plurality of fuel nozzles and a plurality of air nozzles arranged opposite to a combustion chamber are arranged substantially coaxially and fuel and air are supplied to the combustion chamber as a coaxial flow. Has been. In this combustor, mixing is rapidly promoted, and the mixing distance can be shortened. As a result, backfire is suppressed.

JP 2003-148734 A

  Regulations and social demands on the environment are becoming stronger day by day, and further reduction of NOx is required even in a premixed combustion type gas turbine. In the gas turbine combustor described in Patent Document 1, fuel and NOx is reduced by using air as a plurality of coaxial jets and uniformly supplying fuel to the combustion chamber. In Patent Document 1, after air is discharged from the compressor, it passes between the outer cylinder and the combustor liner from the downstream side of the combustor, and a part of the air is cooled on the liner wall surface from the cooling holes provided in the liner. A reverse flow type combustor is used in which the air flows into the combustion chamber, and the remaining air is reversed in the direction of flow on the upstream side of the combustor, flows into the air nozzle, and is ejected into the combustion chamber. A reverse flow combustor can use much of the air for convective cooling of the combustor liner.

  However, in a reverse flow type combustor, since the air flow is reversed upstream of the combustion chamber, an air stagnation region is generated on the outer peripheral side of the combustor, and air flows into an air nozzle disposed on the outer peripheral side. It can be difficult. If the air flow rate is different for each air nozzle, the fuel concentration in the combustion chamber is biased, and NOx may increase.

  In order to suppress this increase in NO, there is a method of adjusting the flow distribution by providing an orifice or the like in the air nozzle on the shaft center side, but there is a possibility that the pressure loss of the combustor increases and the efficiency of the combustor decreases. is there.

  In addition, there is a method of changing the flow rate of fuel supplied for each air nozzle, but a plurality of fuel systems are required according to the air flow rate distribution, which requires an increase in cost and complicated fuel control.

  The objective of this invention is providing the low NOx gas turbine combustor which suppressed the dispersion | variation in the air flow rate supplied to a combustion chamber from each air nozzle.

A combustion chamber for combusting fuel and air and a combustor liner that forms the combustion chamber are provided. A fuel nozzle that ejects fuel and an air nozzle that ejects air are arranged upstream of the combustion chamber, and air is combusted from the downstream side of the combustion chamber. In the combustor that passes the outside of the combustor liner, reverses the flow direction upstream of the combustion chamber, flows into the air nozzle, and is ejected into the combustion chamber, the inlet of the air nozzle disposed radially outside the combustor parts are Ri downstream near than the inlet portion of the air nozzles disposed in the axial center side of the combustor, a plurality of holes air nozzle provided in the wall-like member which is disposed upstream of the combustion chamber, The upstream end surface of the wall-like member protrudes stepwise toward the center of the combustor axis, and an air nozzle is arranged at each step .

  ADVANTAGE OF THE INVENTION According to this invention, the low NOx gas turbine combustor which suppressed the dispersion | variation in the air flow rate supplied to a combustion chamber from each air nozzle can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS The whole block diagram which shows the structure of the gas turbine combustor in 1st Example of this invention. The figure which shows an example of the fuel control of the gas turbine combustor in 1st Example of this invention. The general view which looked at the air nozzle and air nozzle plate in 1st Example of this invention from the upstream. FIG. 4 is a cross-sectional view taken along line AA in FIG. 3 showing the arrangement of the fuel nozzle, air nozzle, and air nozzle plate in the first embodiment of the present invention. The conceptual diagram which showed the mode of the flow of the air nozzle plate upstream in 1st Example of this invention. The conceptual diagram which showed the mode of the flow of the air nozzle plate upstream in the structure of a comparative example. The axial direction sectional view which showed arrangement | positioning of the fuel nozzle in the 2nd Example of this invention, an air nozzle, and an air nozzle plate. The conceptual diagram which showed the mode of the flow of the air nozzle plate downstream in 2nd Example of this invention. An axial direction sectional view showing arrangement of a fuel nozzle, an air nozzle, and an air nozzle plate in another embodiment of the second example of the present invention. An axial direction sectional view showing arrangement of a fuel nozzle, an air nozzle, and an air nozzle plate in the 3rd example of the present invention. The conceptual diagram of the structure of a comparative example and the radial distribution of the fuel concentration at the combustion chamber inlet in the first, second and third embodiments. An axial direction sectional view showing arrangement of a fuel nozzle, an air nozzle, and an air nozzle plate in the 4th example of the present invention. The general view which looked at the air nozzle and air nozzle plate in 4th Example of this invention from the upstream. The conceptual diagram which showed the mode of the flow in the fuel nozzle in the 5th Example of this invention, an air nozzle, an air nozzle plate, and a vent hole. The conceptual diagram which showed the mode of the flow in the fuel nozzle in the 6th Example of this invention, an air nozzle, an air nozzle plate, and a vent hole. An axial direction sectional view showing arrangement of a premixer and a premixer plate in the 7th example of the present invention. An axial direction sectional view showing an example of arrangement of a premixer and a premixer plate in a conventional structure.

  By arranging a large number of fuel nozzles and air nozzles on the same axis and supplying the fuel and air to the combustion chamber as a coaxial flow, the fuel and air are sufficiently mixed and supplied to the combustion chamber. It becomes possible. However, after air is discharged from the compressor, it passes between the outer cylinder and the combustor liner from the downstream side of the combustor, reverses the flow direction on the upstream side of the combustor and then flows into the combustion chamber. In a flow-type combustor, the air flow is reversed upstream of the combustion chamber, so that a stagnation region of air is generated on the radially outer side of the combustor, and air flows into the air nozzle disposed on the radially outer side. It can be difficult. If the air flow rate is different for each air nozzle, the fuel concentration in the combustion chamber is biased, and NOx may increase.

  Therefore, the air nozzle has a number of holes provided in a wall-like member (hereinafter referred to as an air nozzle plate) arranged between the fuel nozzle and the combustion chamber, and the upstream end surface of the air nozzle plate is the axial center portion of the air nozzle plate. Projecting in a staircase shape, and an air nozzle is arranged on each step. With this configuration, the air flow collides with the protruding part of the step provided on the air nozzle plate and recovers the static pressure, eliminating the stagnation area on the outside in the radial direction and supplying air evenly to each air nozzle. Is done.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. An overall cross-sectional view of the gas turbine combustor of the present embodiment is shown in FIG. The compressed air 10 compressed by the compressor 5 flows into the combustor through the diffuser 7 and passes between the outer cylinder 2 and the combustor liner 3. A part of the compressed air 10 flows into the combustion chamber 1 as cooling air 11 of the combustor liner 3. The remainder of the compressed air 10 flows into an air nozzle 21 formed on the air nozzle plate 20 as combustion air 12 and is ejected into the combustion chamber 1. The air nozzle 21 arranged on the axial center side of the air nozzle plate 20 gives an appropriate swirl angle so that the swirling combustion air 12 is swirled around the axis of the combustion chamber 1. By giving swirl to the combustion air 12, a circulation region 100 is formed, and the flame 101 can be stabilized.

  The fuel is supplied to the fuel header 23 through the pilot fuel supply system 15 and the main fuel supply system 16 branched from the fuel mother pipe 14, and flows into a plurality of fuel nozzles 22 connected to the fuel header 23. The fuel flowing into the fuel nozzle 22 is jetted into the combustion chamber 1 together with the combustion air 12 as a coaxial flow, and burns to form a high-temperature combustion gas.

  At this time, it is desirable that the outer diameter and the fuel injection hole diameter of each fuel nozzle 22 have the same shape regardless of the arrangement of the air nozzle plate 20. This is because if the outer diameter and the fuel injection hole diameter of the fuel nozzle 22 are different, the fuel and air mixing characteristics change for each fuel nozzle 22, and the fuel concentration distribution in the combustion chamber 1 becomes non-uniform and NOx may increase. Because there is.

  The fuel mother pipe 14, the pilot fuel supply system 15, and the main fuel supply system 16 are respectively provided with a control valve 17 and a shutoff valve 18, and the ratio of the fuel flow rate supplied to the pilot fuel supply system 15 and the main fuel supply system 16 is provided. Can be controlled.

  FIG. 2 shows the relationship between the gas turbine load and the fuel flow rate supplied to the pilot fuel supply system 15 and the main fuel supply system 16 in this embodiment. Under operating conditions with a low gas turbine load, fuel is supplied to the pilot fuel supply system 15 to increase the fuel concentration at the center of the shaft of the combustion chamber 1 and form a local high temperature region to stabilize the flame. . Under operating conditions with a high gas turbine load, fuel is supplied to the pilot fuel supply system 15 and the main fuel supply system 16, and the concentration distribution in the radial direction of the fuel supplied to the combustion chamber 1 is made uniform to reduce NOx. .

  FIG. 3 is a view of the air nozzle plate 20 as viewed from the upstream side, and FIG. 4 is a sectional view of the combustor upstream side of the AA section of FIG. The upstream end surface of the air nozzle plate 20 has a structure in which the axial center portion of the air nozzle plate 20 protrudes in a stepped manner, and the air nozzles 21 are arranged in each step. FIG. 5 shows a state of the flow of the combustion air 12 in the vicinity of the upstream protruding portion 25 of FIG. The combustion air 12 passes from the radially outer side of the combustor through the flow sleeve 24 and flows toward the central axis of the combustor. The combustion air 12 collides with the upstream protruding portion 25 of the air nozzle plate 20 while flowing toward the central axis of the combustor, and after recovering the static pressure, flows into the combustion chamber 1 from the air nozzle 21 downstream of the protruding portion 25. . By restoring the static pressure before the combustion air 12 flows into the air nozzle 21, it is possible to flow the combustion air 12 while suppressing variations in flow rate regardless of where the air nozzle 21 is arranged on the air nozzle plate 20. Can do. If the protrusion degree of the protrusion part 25 is made into the same grade, the inflow amount of the combustion air 12 which flows into each air nozzle can be made more equal.

  At this time, it is desirable that the fuel nozzle hole at the tip of the fuel nozzle 22 is configured to be closer to the combustion chamber 1 than the upstream end surface of the protruding portion 25 located on the axial center side of the fuel nozzle 22. By comprising in this way, it can prevent that a fuel flows in into the other air nozzle 21 with the combustion air 12 which flows toward the center axis | shaft of a combustor.

  The feature of this embodiment is that a protruding portion 25 is provided on the upstream side of the air nozzle plate 20 and the axial position of the inlet portion of the air nozzle 21 is changed. In the configuration disclosed in Patent Document 1 shown in FIG. 6 as a comparative example, the combustion air 12 changes so that the flow direction of the combustion air 12 turns around when passing through the flow sleeve 24. A stagnation area 102 was generated. For this reason, the air nozzle 21a on the radially outer side of the air nozzle plate 20 is less likely to flow the combustion air 12 than the air nozzle 21b on the axial center side, so that the combustion air 12 is not uniformly supplied to the combustion chamber 1 and the air flow rate is increased. There was a radial bias. The fuel supplied to the fuel header 23 equally flows into the fuel nozzles 22 and is ejected into the combustion chamber 1, so that when the flow rate of the combustion air 12 is biased in the radial direction, the fuel concentration flowing into the combustion chamber 1 There was a possibility that NOx would increase due to the bias. On the other hand, in the present embodiment, by restoring the static pressure of the combustion air 12, the combustion air 12 flows into the air nozzle 21 on the radially outer side of the combustor, so that the combustion air 12 is uniformly supplied to the combustion chamber 1. Is done. For this reason, the concentration distribution in the radial direction of the fuel flowing into the combustion chamber 1 approaches uniformly, and NOx can be reduced. The effect is that the combustor of the present embodiment has a combustion chamber 1 for burning fuel and air, a plurality of air nozzles 21 arranged on the upstream side of the combustion chamber 1, and a plurality of fuels injected into the plurality of air nozzles 21. A combustor in which air is supplied to the combustion chamber 1 through a plurality of air nozzles 21 after passing through the outside of the combustor liner 3 forming the combustion chamber 1 toward the downstream side, Among the plurality of air nozzles 21, the inlet portion of the air nozzle 21 disposed on the radially outer side of the combustion chamber 1 is located downstream of the inlet portion of the air nozzle 21 disposed on the radially inner side of the combustor. It is obtained by.

  In the combustor of the present embodiment, the air nozzle 21 is a number of holes provided in the air nozzle plate 20 which is a wall-like member installed on the upstream side of the combustion chamber 1, and the upstream end surface of the air nozzle plate 20 is a staircase. It protrudes toward the axial center side of the combustion chamber 1 and an air nozzle 21 is arranged at each step. A plurality of steps of the air nozzle plate 20 are provided concentrically, and each step is lower as the step is closer to the axial center of the combustor.

  In the present embodiment, NOx can be reduced with a smaller number of fuel supply systems compared to a method in which a plurality of main fuel supply systems 16 are provided in the radial direction of the combustor to control the flow rate of fuel and adjust the concentration distribution. Control is easy and cost can be reduced.

  In this embodiment, the protruding portions 25 are provided in three steps on the radially outer side of the air nozzle plate 20, but the number of steps may be increased or decreased according to the air nozzle plate 20 or the air nozzle 21.

(Second embodiment)
A second embodiment is shown in FIG. In the present embodiment, the air nozzle plate 20 has a structure in which the axial end portion of the upstream end surface protrudes stepwise, and the downstream end surface protrudes radially outwardly in a step shape, and the air nozzle plate 20 is disposed at each step. Structure.

  FIG. 8 shows the flow of the combustion air 12 and the fuel jets 103a and 103b on the downstream side of the air nozzle plate 20 in this embodiment. The combustion air 12 and the fuel jet 103 a are jetted into the combustion chamber 1 as a coaxial flow while being mixed inside the air nozzle 21. At this time, on the downstream side of the protruding portion 26 of the air nozzle plate 20, the fuel jet 103 a spreads radially outward to form a circulating flow 104. In the shear region 105 where the circulating flow 104 and the fuel jet 103b ejected from the outside in the radial direction collide with the circulating flow 104, a strong turbulence occurs in the flow, and the fuel and the combustion air 12 are further mixed.

  In the present embodiment, the outlet portion of the air nozzle 21 disposed on the radially outer side of the combustion chamber 1 is on the downstream side of the outlet portion of the air nozzle disposed on the radially inner side of the combustion chamber 1. Since the flame can be stably held by the flow 104, and the flame is displaced in the axial direction, the vibration of the combustion energy in the axial direction of the combustor is attenuated and the combustion vibration can be suppressed.

  The feature of this embodiment is that a protruding portion 26 is provided on the downstream side of the air nozzle plate 20 to change the axial position of the outlet portion of the air nozzle 21. In the first embodiment, the air nozzle 21 disposed in the center of the shaft is given a swivel angle so that the swirl around the axis of the combustion chamber 1 is applied, and a circulation region 100 is formed in the combustion chamber 1 to keep the flame 101 stable. It is in flames. However, if the fuel is uniformly supplied to the combustion chamber 1, the flame temperature at the center of the shaft of the combustion chamber 1 may decrease, and the flame 101 may not be stably held only by the circulation region 100. On the other hand, in the present embodiment, the flame 101 can be held by the circulating flow 28 formed on the downstream side of the protruding portion 27 in addition to the circulation region 100, so that stable combustion is possible.

  In this embodiment, by making the plate thickness 200 of each stage of the air nozzle plate 20 constant, the mixing distance between the fuel jet 103 and the combustion air 12 in each air nozzle 21 can be made constant. When configured in this manner, the pressure loss generated when the combustion air 12 flows through the air nozzle 21 can be made constant, so that the flow rate of air flowing into the air nozzle 21 can be made more uniform.

  As another embodiment of the present embodiment, there is a structure in which the plate thickness 200 of the air nozzle plate 20 is increased toward the outer peripheral side of the combustor as shown in FIG. By configuring in this way, the mixing distance between the fuel jet 103 and the combustion air 12 on the outer peripheral side of the combustor can be secured sufficiently longer than in the first embodiment, and NOx generated from the outer peripheral side of the combustor can be ensured. It can be further reduced. The mixing of the axial center portion of the air nozzle plate 20 is slightly worse because the mixing distance is short. As a result, a high-temperature combustion region is formed in the axial center portion of the combustion chamber 1, so that combustion stability is improved. As a result, flame stability is ensured at the central shaft portion of the flame 101, and low NOx combustion is performed on the outer peripheral side of the flame 101. Therefore, both stable combustion and low NOx combustion can be achieved as a whole.

(Third embodiment)
A third embodiment is shown in FIG. In this embodiment, the protruding portion 25 provided on the air nozzle plate 20 is configured to become smaller toward the axial center portion. Expressed by the symbols in FIG. 10, [Formula 1]
201>202> 203
It is comprised so that.

  In the case of this shape, a larger amount of the combustion air 12 collides with the outer peripheral side protruding portion 25 than in the first embodiment, so the flow rate of the combustion air 12 flowing through the outer peripheral side air nozzle 21 is large, and the axial center side air nozzle 21 flows less. For this reason, the fuel concentration is high on the axial center side of the combustion chamber 1, and a high-temperature combustion gas is formed. FIG. 11 shows a conceptual diagram of the fuel concentration distribution at the inlet of the combustion chamber 1 in each embodiment. Since the high-temperature combustion gas on the axial center side spreads radially outward by swirling, a flame can be stably formed even in the low fuel concentration region on the outer peripheral side of the combustion chamber 1. Moreover, since the fuel concentration is low on the outer peripheral side of the combustion chamber 1 and the combustion temperature is lowered, the metal temperature of the combustor liner 3 can be kept low.

  Since this embodiment can stabilize the flame more than the first embodiment, it is suitable for burning a fuel having a low calorific value.

(Fourth embodiment)
A fourth embodiment is shown in FIG. In this embodiment, the passage area 204 of the combustion air flowing between the upstream end face of the air nozzle plate 20 and the fuel header 23 is the opening area of the air nozzle 21 on the axial center side from the passage face, indicated by 205. The total is configured to be smaller than 205S. FIG. 13 shows the air nozzle 21 as viewed from the upstream side. The total opening area 205S of the air nozzles 21 on the axial center side of the passage surface means the total opening area of the air nozzles indicated by hatching in FIG. Equation 2 shows the relationship between the passage area 204 and the total opening area 205S.
[Formula 2]
204 <205S

  Further, the passage area 204 of each stage is configured to be narrower toward the axial center of the air nozzle plate 20.

  In the case of this shape, that is, a shape in which the radial air passage area in a certain step is smaller than the total opening area of the air nozzles 21 provided in the step radially inward from this step. The flow rate of air flowing into the air nozzle 21 provided at each stage of the protruding portion 25 is determined by the passage area 204 serving as the throat portion, and the flow rate of air flowing into the air nozzle 21 on the axial center side is reduced. As in the example, the flame can be stabilized and the metal temperature of the combustor liner 3 can be kept low.

(Fifth embodiment)
A fifth embodiment is shown in FIG. In the present embodiment, a vent hole 30 through which the combustion air 12 flows is provided so as to be in contact with the protruding portion 25 of the air nozzle plate 20.

  In the case of this shape, the combustion air 12 collides with the protruding portion 25 of the air nozzle plate 20 and flows into the air nozzle 21 and the vent hole 30. The combustion air 12 flowing into the air nozzle 21 flows into the combustion chamber 1 while being mixed with fuel as a coaxial jet inside the air nozzle 21 to form a flame. The combustion air 12 that has flowed in from the vent hole 30 flows into the combustion chamber 1 along the protruding portion 27 of the air nozzle plate 20 on the combustion chamber 1 side, and cools the air nozzle plate 20.

  In the second embodiment, when the combustion air 12 collides with the protruding portion 25 of the air nozzle plate 20, the static pressure is not fully recovered and a stagnation region is formed in the vicinity of the air nozzle plate 20. May not easily enter the air nozzle 21 and the pressure loss may increase. In the present embodiment, by providing the vent hole 30 for allowing a part of the combustion air 12 to flow into the combustion chamber 1, formation of a stagnation region can be prevented, and an increase in pressure loss can be avoided.

(Sixth embodiment)
A sixth embodiment is shown in FIG. This embodiment is another embodiment of the fifth embodiment, and a vent hole 30 penetrating from the protruding portion 25 of the air nozzle plate 20 to the air nozzle 21 is provided.

  With this configuration, a part of the combustion air 12 that has collided with the protruding portion 25 of the air nozzle plate 20 passes through the vent hole 30 and is ejected from the wall surface of the air nozzle 21 to be turbulent inside the air nozzle 21. 106 can be generated to promote mixing of the combustion air 12 and the fuel.

(Seventh embodiment)
A seventh embodiment is shown in FIG. The present invention can also be applied to a gas turbine combustor including a plurality of premixers.

  In this embodiment, the combustion air 12 passes through the flow sleeve 24 from the outer peripheral side of the combustor and flows toward the axial center of the combustor. The combustion air 12 collides with the protrusions 34 provided on the premixer 31 and the premixer plate 33 in the middle of flowing to the shaft center portion, recovers static pressure, and a plurality of air provided upstream of the premixer 31. It flows into the premixer 31 from the hole 32. The air holes 32 provided in the premixer 31 are formed so that the inflowing combustion air 12 has a swirling component. The fuel is injected from the upstream side of the premixer 31, rapidly mixed by the swirling of the combustion air 12, and flows into the combustion chamber 1 to form a flame. NOx can be reduced by thoroughly mixing the combustion air 12 and fuel in the premixer 31 and burning them.

  In the combustor in which the axial positions of the premixer 31 and the air holes 32 are aligned as shown in FIG. 17, the combustion air 12 that has passed through the flow sleeve 24 has a velocity component directed in the axial direction. There is a possibility that a large amount of the combustion air 12 flows into the air holes 32 facing outward in the radial direction, causing a drift of the combustion air 12 inside the premixer 31, and the combustion air 12 and the fuel are not sufficiently mixed. In this embodiment, the combustion air 12 is collided with the premixer 31 and the premixer plate 33, and once the static pressure is recovered, it flows into the premixer 31. Therefore, the premixer 31 is evenly distributed in the circumferential direction. Combustion air 12 can be supplied at a flow rate close to NOx, and NOx can be reduced.

DESCRIPTION OF SYMBOLS 1 Combustion chamber 2 Outer cylinder 3 Combustor liner 4 Transition piece 5 Compressor 6 Turbine 7 Diffuser 8 End cover 10 Compressed air 11 Liner cooling air 12 Combustion air 14 Fuel mother pipe 15 Pilot fuel supply system 16 Main fuel supply system 17 Control valve 18 Shut-off valve 20 Air nozzle plate 21, 21a, 21b Air nozzle 22 Fuel nozzle 23 Fuel header 24 Flow sleeve 25 Protruding part (upstream side)
26 Protruding part (downstream side)
30 Ventilation hole 31 Premixer 32 Air hole 33 Premixer plate 34 Premixer plate protrusion 100 Circulation region 101 Flame 102 Stagnation region 103, 103a, 103b Fuel jet 104 Circulation flow 105 Shear region 106 Disturbance 200 Air nozzle plate plate Thickness 201, 202, 203 Protrusion height 204 Air nozzle plate-fuel header passage area 205 Air hole opening area

Claims (4)

A combustion chamber for combusting fuel and air, a plurality of air nozzles arranged upstream of the combustion chamber, and a plurality of fuel nozzles for injecting fuel to the plurality of air nozzles form the combustion chamber. a combustor air is supplied to the combustion chamber through the plurality of air nozzles the outer combustor liner after passing upward flow side,
Wherein the plurality of air nozzles, inlet air nozzle disposed radially outside of the combustor, Ri downstream near than the inlet portion of the air nozzles disposed radially inwardly of the combustor,
The air nozzle is a number of holes provided in a wall-like member installed on the upstream side of the combustion chamber, and the upstream end surface of the wall-like member protrudes stepwise toward the axial center side of the combustor. The combustor , wherein the air nozzle is disposed at each step . The combustor according to claim 1.
The combustor, wherein an outlet portion of an air nozzle disposed on the radially outer side of the combustor is located downstream of an outlet portion of an air nozzle disposed on the radially inner side of the combustor. The combustor according to claim 1 or 2,
A plurality of steps are provided concentrically on the wall-like member, and each step is lower as the step on the axial center side of the combustor
A combustor configured to be configured as follows.   The combustor according to claim 3.
  The air passage area in the radial direction at a certain stage has an air node provided in a stage radially inward of the stage.
A combustor characterized in that it is smaller than the total opening area of the slur.

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