JPH11141878A - Gas turbine combustor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To further reduce the NOX emitted from a premixing gas turbine combustor by making the flow of air flowing in the combustor uniform. SOLUTION: In the main body 20 of a gas turbine combustor, eight fuel burners 22 are arranged along a circumference and a pilot burner 21 is provided at the center. The air 50 from a compressor 30 flows in the main body 20 as air flows 50a, 50b, and 50c, flows to the front sections of the burners 22 through the peripheries of the burners 22, and forms a mixed gas with fuel ejected from the front ends of the burners 22 and the mixed gas is ignited by the flame coming up from the front end 21a of the pilot burner 21 and forms a flame 22a and a combustion gas 41. On the air flowing-in side of the main body 20, a straightening vane 1 is provided and fixed to the periphery of the pilot burner 21 by welding. Since many small holes are formed through the vane 1, uniform air flows are formed around the burners 22 by distributing the flowing-in air and a uniform mixed gas is formed at the front end of each burner 21. Therefor, the NOX emitted from the gas turbine combustor can be reduced further.

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 is mainly applied to a premixing type combustor so as to eliminate uneven air flow flowing into a combustor inlet and to form a uniform flow. It was done.

[0002]

2. Description of the Prior Art FIG. 5 is a cross-sectional view of a conventional premixing type combustor. In the figure, reference numeral 20 denotes a combustor main body, and a pilot burner 21 is provided at the center thereof.
Fuel is blown out from the tip portion 21a to form a flame for ignition. Numeral 22 designates eight fuel nozzles which are circumferentially arranged at equal pitches, blow out fuel from the tip and mix with air flowing from the surroundings to form a flame 22a. Reference numeral 23 denotes a support member, which supports the disc-shaped member 25 at equal intervals circumferentially. Reference numeral 24 denotes a swirler, which is attached at several intervals around the tip of the fuel burner 22, supports the cylinder 26, and rotates the air flowing from the periphery in the circumferential direction to uniformly guide the air around the fuel burner. Things.

[0003] 30 is a compressor, 31 is an air separator, 3
Reference numeral 2 denotes a cavity provided at the root of the rotor blade on the gas turbine side, and reference numeral 33 denotes a radial hole, which is a hole for guiding air from the compressor 30 to the moving blade 34 from the cavity 32 to cool the moving blade 34. 35 is a stationary blade, which is arranged alternately with the rotor blade 34 to form a gas turbine combustion gas passage;
The high-temperature combustion gas 41 burned by the combustor 20 in this gas passage.
Flows, and the rotor blades 34 are rotated.

In the combustor having the above-described structure, air 50 from the compressor 30 flows outside the combustor 20 from the space in the vehicle interior 40 as indicated by an arrow 50a, and the support member 23, the disc 25 Through the space formed by
b → flows into the combustor 20 and 50c → flows around the fuel nozzle 22 and the pilot burner 21 as shown in FIG.
The fuel is mixed with the fuel at the tip 21a of the pilot burner 21 to generate an ignition flame. Further, the swirler 24 uniformly flows into and flows into the tip of the fuel burner 22, mixes with the fuel injected from the tip, ignites with the flame of the pilot burner 21 to form a flame 22 a, and generates the combustion gas 41. Generated and sent to the combustion gas passage on the gas turbine side. Employing combustor such premixing method, it is so mixed with only uniform air and fuel can in part forming the premixed gas that low NO _x reduction can be achieved.

[0005]

As described above, in a gas turbine combustor adopting a premixing method, air is made to flow uniformly in a portion where premixing is formed, and air and fuel are mixed as uniformly as possible. Low NO
_x conversion becomes possible. However, in reality, the number of fuel outlets cannot be so large, the surroundings of the combustion chamber in the vehicle compartment are complicated and the air flow path is complicated, and the air flow is biased, resulting in the combustion chamber inside. The inflowing air was not always homogeneous, and did not result in the formation of a uniform mixture. Accordingly, it has been strongly desired for a combustor adopting a premixing method to form a more uniform air-fuel mixture by forming a uniform air flow in the combustor.

Therefore, in the present invention, the air flowing into the combustor at the inlet of the combustor is rectified to make the air flow uniform in the cross section of the combustor, and the air-fuel mixture formed at the plurality of fuel nozzles is uniform around the periphery. next, thereby it has been made as object to propose a gas turbine combustor so as to improve further the well to low NO _x reduction combustion efficiency.

[0007]

The present invention provides the following means for solving the above-mentioned problems.

[0008] A pilot burner is arranged on a shaft in the combustor main body, and a plurality of fuel burners are arranged at equal intervals around the pilot burner, and air from the compressor is guided into the combustor main body.
The fuel burner is allowed to flow out from the periphery toward the tip, and a fuel-air mixture is generated with the fuel ejected from the fuel burner tip,
In a gas turbine combustor that generates combustion gas by igniting with the pilot burner, a rectifying plate disposed so as to close an axial cross section is provided on an air inflow side of the combustor main body, and air flows through the rectifying plate. A gas turbine combustor having a number of small holes.

[0009] The combustor of the present invention is provided with a current plate, and the current plate has a large number of small holes. Therefore, the air flowing in from the compressor flows through these many small holes on the air inflow side of the combustor and is rectified, so that a uniform flow is obtained in the cross section of the combustor. The air flowing into the combustor body passes through a complicated and complicated space in the vehicle cabin from the compressor and flows into the combustor, so that the air does not always flow uniformly within the cross section of the combustor. Therefore, the air is rectified by passing through a number of uniformly arranged small holes in the rectifying plate, resulting in an almost uniform flow in the cross section of the combustor.
The fuel flows out from the periphery of each fuel nozzle arranged at equal intervals in the circumferential direction to the tip with a uniform flow, and generates an air-fuel mixture. Each air-fuel mixture generated in each fuel nozzle becomes a uniform mixture, respectively, thereby to improve further the combustion efficiency than the conventional, it is to promote a low NO _x reduction.

[0010]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a sectional view of a gas turbine combustor according to one embodiment of the present invention.
In the figure, the present invention is a conventional combustor body provided with a rectifying plate 1, and the other structure is the same as the conventional example shown in FIG. Therefore, the same reference numerals are given to the common parts as in the related art, detailed description of these common parts is omitted, and the characteristic parts of the present invention will be described below.

In FIG. 1, a current plate 1 of the present invention has a disk shape provided at an air inflow portion of a combustor main body 20.
The central pilot burner 21 and the surrounding 8
Each of the fuel burners 22 penetrates through the fuel burners 22 and is fixed to the periphery of the pilot burner 21 by welding, and can be taken out integrally with the burner 21. The detailed structure will be described in detail below.

FIG. 2 is an assembly diagram of the current plate 1 described above. In the figure, a current plate 1 forms a disk by combining eight punched metals 11. Each punch metal 11
Has semicircular notches 13 on both sides in the radial direction.
a and 13b are provided, and each of the eight punch metals is joined to the adjacent punch metal to form eight fuel nozzles 2
2 are formed at equal pitches around the periphery to form a circular shape.

The punch metal 11 has a large number of small holes 12.
Are perforated to allow air to pass through. A circular arc formed by dividing a circle into eight is formed on each of the outer and inner peripheral sides of the punch metal 11, and a disk is formed by combining eight punch metals 11, and a pilot nozzle 21 is provided at the center of the disk. Form a hole therethrough.

Reference numeral 15 denotes a rib, which covers the joint with a predetermined width t along the two radial directions of the punched metal from the periphery of the center hole as indicated by oblique lines in the figure, and is integrally formed along the outer periphery of the disk. Is formed. The eight ribs 15 are attached to the joints of the eight punch metals 11 from the side where air flows in.

In the drawing, reference numeral 16 indicated by a two-dot chain line denotes a pedestal, which is in contact with a radially joined portion of each punch metal and is fixed to the inner wall surface of the combustor body 20.
Numerals 6 serve to prevent vibration of the current plate 1.

When the specific dimensions of the above-described current plate 1 applied to an actual machine are shown, the outer diameter D ₁ of the current plate ₁ is 290.
mm, diameter D ₂ of the combustion chamber cylinder is 316 mm, punch metal 11
Is 3 mm thick. The width t of the rib 15 is 1.6 mm,
The thickness is 3 mm. The cradle 16 has an arc length of 2
Preferably, the dimensions are about 0.5 mm, a height of about 18 mm, and a thickness of about 10 mm. The hole diameter of the combustion nozzle is 34 mm, and the hole diameter of the central pilot burner is 90 mm. A plurality of small holes 12 of the punched metal 11 were uniformly formed with a hole diameter of 5 mm and a pitch of 6.5 mm, and the opening ratio was set to 53%.

FIG. 3 is a view showing an assembled state of one punched metal. FIG. 3A shows a punched metal 11 having holes 13a and 13b having a radius, an inner circular arc 14, an outer circular arc 14 ', respectively.
It is composed of a number of small holes 12. (B) is a rib 15
And a shape having a predetermined width t to cover the semicircular hole and the outer peripheral portion of the joint portion and the fuel nozzle, respectively. (C) shows a pedestal, which has an arc shape along the combustion chamber tube and the rectifying plate.

FIG. 4 is a cross-sectional view in which a current plate is mounted. The current plate 1 is mounted around the pilot nozzle 21 by welding 27 so that it can be taken out integrally with the pilot nozzle 21. Ribs 15 are attached to the joining portions of the punch metal on the flow-inflow side of the current plate 1 at the air 50 side. In addition, the diameter of the current plate 1 is made slightly smaller than the inner wall of the combustor main body 20, and the pedestal 16 is attached to the inner wall of the combustor main body 20 so as to be located at the joint of the punch metal. The receiving table 16 is in contact with the outer peripheral surface of the current plate 1 to prevent the current plate 1 from vibrating.

As shown in FIG. 1, even in the combustor provided with the straightening plate 1 as described above, the air 50 from the compressor 30 flows from the periphery of the combustor body 20 to the support member 23 as shown in FIG.
The gas flows into the combustor body 20 from the space formed by the disk 25, and flows through the small holes 12 of the current plate 1 as shown in FIG.
Flows uniformly over the circular cross section of

As a result, a uniform air flow also occurs around the eight fuel nozzles arranged around the inside of the combustor 20,
At the tip of each of the eight fuel nozzles 21, a uniform mixture is formed and burned.

[0021]

According to the gas turbine combustor of the present invention, a pilot burner is arranged on a shaft in a combustor main body, and a plurality of fuel burners are arranged around the pilot burner at equal intervals to burn air from a compressor. A gas turbine combustion that guides the fuel into the main body, flows out from the periphery of the fuel burner toward the tip, generates a mixture with fuel ejected from the tip of the fuel burner, and ignites by the pilot burner to generate combustion gas. A rectifier plate is provided on the air inflow side of the combustor main body, the rectifier plate being disposed so as to close an axial cross section, and the rectifier plate is provided with a number of small holes through which air flows.
With such a configuration, the air flowing into the combustor is rectified by passing through the small holes of the flow straightening plate, and flows out to the tips of a plurality of fuel nozzles in a uniform flow, and is uniformly mixed with the fuel at each nozzle. the combustion efficiency is improved over conventional and is intended to further improve the low NO _x reduction.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a gas turbine combustor according to one embodiment of the present invention.

FIG. 2 is a plan view of a current plate of the gas turbine combustor according to one embodiment of the present invention.

3A and 3B show the configuration of the current plate shown in FIG. 2, wherein FIG. 3A shows a punch metal, FIG. 3B shows a rib, and FIG.

FIG. 4 is a cross-sectional view showing a gas turbine combustor according to an embodiment of the present invention, in which a current plate is attached.

FIG. 5 is a sectional view of a conventional gas turbine combustor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rectifier plate 11 Punch metal 12 Small hole 13a, 13b Semicircular notch 15 Rib 16 Cradle 20 Combustor main body 21 Pilot burner 22 Fuel nozzle 23 Supporting material 24 Swirler 25 Disk 26 Cylinder 27 Welding 30 Compressor 41 Combustion gas 50 air

Claims (1)

[Claims] Claims: 1. A pilot burner is arranged around a shaft in a combustor main body, and a plurality of fuel burners are arranged at equal intervals around the pilot burner, and air from a compressor is guided into the combustor main body.
In the gas turbine combustor which is caused to flow out from the periphery of the fuel burner toward the tip, generates an air-fuel mixture with the fuel ejected from the tip of the fuel burner, and is ignited by the pilot burner to generate combustion gas, the combustor A gas turbine combustor, comprising: a rectifying plate disposed on an air inflow side of a main body so as to close an axial cross section, and the rectifying plate is provided with a number of small holes through which air flows.