JP7205300B2 - Multi-nozzle burner and combustor - Google Patents

Description

The present invention relates to multi-nozzle burners and combustors.

For example, Patent Literature 1 discloses a gas turbine combustor that burns hydrogen-containing fuel. The gas turbine combustor disclosed in Patent Document 1 includes a plurality of small-diameter fuel nozzles upstream of the combustion chamber, and a multi-nozzle burner that supplies fuel from each of the fuel nozzles. Further, in the gas turbine combustor disclosed in Patent Document 1, both air and fuel are injected into the combustion chamber from an air hole plate provided downstream of the fuel nozzle and having a large number of air holes. In this way, by supplying fuel from a plurality of small-diameter fuel nozzles, it is possible to rapidly mix with air and form a combustion state close to a premixed flame while forming a diffusion flame. .

JP 2013-108667 A

By the way, in recent years, in order to realize low NOx, when burning natural gas or the like as fuel, the air-fuel ratio is increased. However, in such a multi-nozzle burner, since flames are formed in the vicinity of each fuel nozzle, it is difficult for the flames to interfere with each other, resulting in low flame holding performance. Therefore, it is difficult to increase the air-fuel ratio for the purpose of reducing NOx in the multi-nozzle burner.

SUMMARY OF THE INVENTION The present invention has been made in view of the problems described above, and an object of the present invention is to improve flame holding performance in a multi-nozzle burner.

The present invention provides a multi-nozzle burner having a plurality of fuel nozzles for supplying fuel to a combustion chamber as a first means related to a multi-nozzle burner for solving the above problems, wherein An air hole plate is provided at a position corresponding to the nozzle and has an air hole through which air is injected toward the combustion chamber, and the tip of the fuel nozzle protrudes from the air hole plate toward the combustion chamber. A configuration is adopted in which a fuel injection port for injecting fuel in a direction intersecting with the direction of flame formation is formed at a portion protruding toward the combustion chamber side.

As a second means relating to the multi-nozzle burner, in the first means, a configuration is adopted in which a plate is provided at the tip of the fuel nozzle and guides the fuel in the radial direction of the fuel nozzle. .

As a third means relating to the multi-nozzle burner, in the first or second means, a configuration is adopted in which the plate is provided in the fuel nozzle arranged radially toward the center of the combustion chamber. .

As a fourth means relating to the multi-nozzle burner, in any one of the first to third means, the plate is shaped in a polygonal shape with corners formed in the direction of the adjacent fuel nozzles, configuration is adopted.

As a first means relating to a combustor, a configuration is adopted in which the multi-nozzle burner according to any one of claims 1 to 4 and a combustor liner in which a combustion chamber is formed are provided.

According to the present invention, it is possible to inject fuel radially outward from the fuel injection port formed in the peripheral surface of the fuel nozzle. As a result, fuel injected from adjacent fuel nozzles interferes with each other. Therefore, the flames formed in the vicinity of each fuel nozzle interfere with each other, improving the flame holding performance.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic cross section including the multi-nozzle burner which concerns on 1st Embodiment of this invention. It is a schematic cross section containing the multi-nozzle burner which concerns on 2nd Embodiment of this invention. FIG. 7 is a schematic front view showing the arrangement of fuel nozzles and diffusion plates of a multi-nozzle burner according to a second embodiment of the present invention; It is a schematic cross section showing a modification of the fuel nozzle.

An embodiment of a multi-nozzle burner according to the present invention will be described below with reference to the drawings.

[First embodiment]
First, the multi-nozzle burner 1 according to this embodiment is provided in a gas turbine (not shown). The gas turbine includes a compressor, turbine and combustor 100 (not shown). The gas turbine compresses air taken in from outside air to a predetermined pressure in the compressor to generate combustion air, and burns fuel in the combustor 100 using the combustion air as an oxidant. Furthermore, the gas turbine generates rotational power by rotating the turbine with combustion gas generated by burning fuel in the combustion chamber N.

As shown in FIG. 1 , combustor 100 includes combustor liner 110 , casing, and multi-nozzle burner 1 .

The multi-nozzle burner 1 is provided for the combustor liner 110 and is a device for injecting fuel into the combustor liner 110. As shown in FIG. there is

The fuel supply section 2 includes a fuel supply pipe 2a and a plurality of fuel nozzles 2b. The fuel supply pipe 2a is connected to an external fuel tank and a plurality of fuel nozzles 2b, and functions as a header pipe.

One end of the fuel nozzle 2b is connected to the fuel supply pipe 2a, and the tip of the fuel nozzle 2b is directed toward the combustor liner 110 in a state in which the tip protrudes from an air hole h, which will be described later, of the air hole plate 3. It is a tubular member with a A plurality of fuel nozzles 2 b are arranged and each guides fuel to the combustor liner 110 . Further, the fuel nozzle 2b has a closed tip, and a plurality of fuel injection ports n are formed on a peripheral surface near the tip (a portion protruding toward the combustion chamber N). The fuel flowing into the fuel nozzle 2b intersects the radial direction of the fuel nozzle 2b, that is, the flame formation direction, and is injected toward the adjacent fuel nozzle 2b from the fuel injection port n.

The air hole plate 3 is a disk-shaped member provided on the injection port side of the fuel nozzle 2b, and has an air hole h at a position corresponding to the injection port of the fuel nozzle 2b. That is, the air hole plate 3 is formed with a plurality of air holes h, and when viewed from the combustor liner 110 side, each air hole h is arranged so as to surround the injection port of each fuel nozzle 2b. Such air hole plate 3 is fixed to the end of combustor liner 110 .

The combustor liner 110 has a substantially cylindrical shape and is surrounded by a casing (not shown). The interior of the combustor liner 110 is defined as a combustion chamber N in which a flame is formed.
Further, the gap between the casing surrounding combustor liner 110 and the peripheral surface of combustor liner 110 serves as a combustion air flow path that guides combustion air from the downstream side to the upstream side in the direction of flame formation. That is, the combustion air flows into the casing in a direction opposite to the direction of flame formation. A combustion air flow path is formed from the gap between the casing and the peripheral surface of the combustor liner 110 to the interior of the combustor liner 110 via between the fuel nozzle 2 b and the air hole plate 3 . A straightener is provided on the combustion air flow path.

The operation of such combustor liner 110 will be described.
In the combustor liner 110 , the combustion air supplied into the casing of the combustor 100 passes through the combustion air flow path and is injected through the air holes h of the air hole plate 3 . At this time, the combustion air surrounds the fuel nozzle 2b and flows in the axial direction of the fuel nozzle 2b. The combustion air injected into the combustor liner 110 through the air holes h contacts the fuel injected from the fuel nozzle 2b. Then, the fuel and the combustion air are mixed to form a combustion gas, forming a circulation flow and spreading inside the combustor liner 110 .

At this time, the fuel is guided to the fuel nozzle 2b through the fuel supply pipe 2a of the fuel supply section 2. As shown in FIG. The fuel injected from the fuel injection port n on the peripheral surface of the fuel nozzle 2b is diffused in the radial direction of the fuel nozzle 2b. Since the fuel is injected in the radial direction from all the fuel nozzles 2b, the injected fuels ignite while interfering with each other in the vicinity of each fuel nozzle 2b. Therefore, the flames of the fuel nozzles 2b interfere with each other, improving the flame holding performance. As a result, when burning natural gas or the like, it is possible to stabilize the flame even if the air-fuel ratio is increased more than before, and it is possible to further reduce NOx.

[Second embodiment]
A modification of the multi-nozzle burner 1 according to the first embodiment will be described as a second embodiment with reference to FIG. In addition, about the same structure as the said 1st Embodiment, the code|symbol is made the same and description is abbreviate|omitted.

In the multi-nozzle burner 1 according to this embodiment, the fuel supply section 2 further includes a diffusion plate 2c. Further, in this embodiment, as shown in FIG. 2, the diffusion plate 2c is a flat plate-shaped member provided at the bottomed end of the fuel nozzle 2b along the fuel injection direction (the direction orthogonal to the flame formation direction). is. As shown in FIG. 3 , the diffusion plate 2 c has a hexagonal shape when viewed from the front, and is provided in a plurality of (four in this embodiment) fuel nozzles 2 b on the axial center side of the combustor liner 110 . In the fuel nozzle 2b provided with such a diffusion plate 2c, the injected fuel is guided radially by the diffusion plate 2c.

Also in this embodiment, since the fuel is injected in the radial direction, the injected fuels ignite while interfering with each other in the vicinity of each fuel nozzle 2b. Therefore, the flames of the fuel nozzles 2b interfere with each other, improving the flame holding performance. As a result, when burning natural gas or the like, it is possible to stabilize the flame even if the air-fuel ratio is increased more than before, and it is possible to further reduce NOx.

Furthermore, in this embodiment, the diffusion plate 2c radially guides the fuel injected from the fuel injection port n of the fuel nozzle 2b during combustion. As a result, the fuel injected from the fuel nozzle 2b provided with the diffusion plate 2c is more reliably guided in the radial direction, and flames are more likely to interfere.

Moreover, according to the multi-nozzle burner 1 according to this embodiment, the diffusion plate 2c is hexagonal, that is, has a polygonal shape forming an angle toward the adjacent fuel nozzles 2b. When the fuel is diffused along the diffusion plate 2c, more fuel is guided from the center toward the corners of the diffusion plate 2c. Therefore, by arranging such a diffusion plate 2c with the corner facing the adjacent fuel nozzles 2b, it is possible to more reliably guide the fuel to the adjacent fuel nozzles 2b, and the adjacent flames are more likely to interfere. .

Further, on the axial center side of combustor liner 110, the flow along the axial direction is strong, and the fuel tends to flow in the axial direction. By providing the diffuser plate 2c for the fuel nozzle 2b on the center side, the flame holding performance on the axial center side of the combustor liner 110 is improved. Therefore, it becomes easy for the flames generated by the plurality of fuel nozzles 2b of the multi-nozzle burner 1 to be integrated to form one flame.

Although the preferred embodiments of the present invention have been described above with reference to the drawings, the present invention is not limited to the above embodiments. The various shapes, combinations, and the like of the constituent members shown in the above-described embodiment are merely examples, and can be variously changed based on design requirements and the like without departing from the gist of the present invention.

In the above embodiment, the fuel is injected radially outward from the fuel nozzle 2b so as to be substantially perpendicular to the flame formation direction, but the present invention is not limited to this. As shown in FIG. 4, the fuel is injected from the fuel nozzle 2b in a direction inclined toward the flame forming direction from the radially outer side by slanting the fuel injection port n from the radial direction. It may be In this case, the flame formed is farther from the air hole plate 3 than the flame formed in the above embodiment, so the air hole plate 3 is less likely to be exposed to high temperatures.

In addition, in the above-described second embodiment, the diffusion plate 2c is provided only on the plurality of fuel nozzles 2b on the center side, but the present invention is not limited to this. For example, the diffusion plate 2c may be provided for all fuel nozzles 2b. In this case, the diffusibility of the fuel in the radial direction can be further improved, and the flame holding performance can be further improved.

Further, in the second embodiment, the diffuser plate 2c is set to have a hexagonal shape, but the present invention is not limited to this. Various polygonal shapes are possible depending on the arrangement of the fuel nozzle 2b. Also, the diffusion plate 2c may be circular.

1 multi-nozzle burner 2 fuel supply part 2a fuel supply pipe 2b fuel nozzle 2c diffusion plate 3 air hole plate 100 combustor 110 combustor liner n fuel injection port h air hole N combustion chamber

Claims (3)

A multi-nozzle burner comprising a plurality of fuel nozzles for supplying fuel to a combustion chamber,
an air hole plate provided upstream of the combustion chamber and at a position corresponding to the fuel nozzle and having an air hole through which air is injected toward the combustion chamber ;
A plate provided at the tip of the fuel nozzle and guiding the fuel in the radial direction of the fuel nozzle,
The fuel nozzle has a tip protruding from the air hole plate toward the combustion chamber, and fuel is injected in a direction intersecting the direction of flame formation at the portion protruding toward the combustion chamber. An injection port is formed ,
The plate is shaped into a polygonal shape with corners oriented toward adjacent fuel nozzles.
A multi-nozzle burner characterized by: 2. The multi-nozzle burner according to claim 1 , wherein said plate is provided on said fuel nozzle arranged on the center side in the radial direction of said combustion chamber . A multi-nozzle burner according to claim 1 or 2;
a combustor liner in which a combustion chamber is formed;
A combustor comprising:

Images