BURNER MODULE

Abstract

Provided is a burner module including burner rings sharing the same center but have different diameters. Each burner ring includes micro burners that are lined up in an annular shape and discharge a fuel-air mixture including hydrogen and air. Each micro burner includes: an air passage through which the air flows; and a hydrogen injection hole injecting the hydrogen into the air which has flowed through the air passage or the air which has not yet flowed through the air passage, in a direction intersecting with a flow direction of the air. At least one of the burner rings is an irregular burner ring. The irregular burner ring includes regular regions and irregular regions alternately lined up in a circumferential direction. The amount of fuel-air mixture discharged per unit area in the irregular region is smaller than the amount of fuel-air mixture discharged per unit area in the regular region.

Description

TECHNICAL FIELD

The present disclosure relates to a burner module.

BACKGROUND ART

PTL 1 below discloses a fuel injector (corresponding to a burner module of the present disclosure) including: fuel injection holes that are open in a radial direction; and air guide grooves that guide air to fuel injected from the fuel injection holes. According to this fuel injector, even in the case of using fuel, such as hydrogen, having high reactivity, flashback can be prevented while suppressing the generation of NOx.

CITATION LIST

Patent Literature

• • PTL 1: Japanese Laid-Open Patent Application Publication No. 2020-106258

SUMMARY OF INVENTION

Technical Problem

According to the fuel injector described in PTL 1, the fuel injection holes and the air guide grooves are located so as to be lined up in an annular shape. According to the fuel injector configured as above, a large flame portion may be generated, and combustion oscillations may occur by the movement of the large flame portion in a circumferential direction.

An object of the present disclosure is to provide a burner module that can prevent flashback while suppressing the generation of NOx and suppress combustion oscillations when hydrogen is used as fuel.

Solution to Problem

A burner module according to one aspect of the present disclosure includes burner rings that share the same center but have different diameters. Each of the burner rings includes micro burners that are lined up in an annular shape and discharge a fuel-air mixture including hydrogen and air. Each of the micro burners includes: an air passage through which the air flows; and a hydrogen injection hole that injects the hydrogen into the air which has flowed through the air passage or the air which has not yet flowed through the air passage, in a direction intersecting with a flow direction of the air. At least one of the burner rings is an irregular burner ring. The irregular burner ring includes regular regions and irregular regions which are alternately lined up in a circumferential direction. The amount of fuel-air mixture discharged per unit area in the irregular region is smaller than the amount of fuel-air mixture discharged per unit area in the regular region.

Advantageous Effects of Invention

The above configuration can provide a burner module that can prevent flashback while suppressing the generation of NOx and suppress combustion oscillations when hydrogen is used as fuel.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a sectional view of a combustor.

FIG. 2 is a front view of a burner module.

FIG. 3 is an enlarged view of a part of the burner module shown in FIG. 2.

FIG. 4 is a sectional view taken along line IV-IV of FIG. 3.

DESCRIPTION OF EMBODIMENTS

Combustor

Hereinafter, a burner module 100 according to an embodiment will be described. First, a combustor 101 including the burner module 100 will be described. FIG. 1 is a sectional view of the combustor 101. In the following, a front side of the combustor 101 which is the left side on the paper surface of FIG. 1 is simply referred to as a “front side,” and a rear side of the combustor 101 which is the right side on the paper surface of FIG. 1 is referred to as a “rear side.” The combustor 101 of the embodiment is a can combustor in which cans are located around a center axis of the gas turbine engine. However, the type of the combustor 101 is not limited, and for example, the combustor 101 may be an annular combustor.

As shown in FIG. 1, the combustor 101 includes: a combustion liner 103 that defines a combustion chamber 102 therein; the burner module 100 that has a disk shape and discharges a fuel-air mixture including hydrogen and air toward the combustion chamber 102; a support tube 104 that supports the burner module 100; and a housing 105 that accommodates the combustion liner 103, the burner module 100, and the support tube 104.

An annular air introduction passage 106 is defined between the combustion liner 103 and the housing 105. The air is supplied into the air introduction passage 106 from the rear side of the air introduction passage 106. The air supplied to the air introduction passage 106 flows to the front side in the air introduction passage 106. Moreover, the air flowing in the air introduction passage 106 flows into the support tube 104 through air introduction holes 107 of the support tube 104, flows through a straightening plate 108, and is supplied to the burner module 100. Furthermore, a hydrogen supply pipe 109 is connected to the burner module 100, and the hydrogen is supplied through the hydrogen supply pipe 109 to the burner module 100.

The burner module 100 mixes the air and the hydrogen, supplied to the burner module 100, to generate the fuel-air mixture and discharges the fuel-air mixture toward the combustion chamber 102. The fuel-air mixture discharged from the burner module 100 is combusted by being ignited by an igniter 110 located at the combustion liner 103. Combustion gas generated by the combustion of the fuel-air mixture flows to the rear side in the combustion chamber 102. As above, the combustor 101 of the present embodiment is of a reverse flow type in which a flow direction of the air flowing in the air introduction passage 106 and a flow direction of the combustion gas flowing in the combustion chamber 102 are opposite to each other. However, the combustor 101 may be of an axial flow type in which the flow direction of the air and the flow direction of the combustion gas are the same as each other.

Burner Module

Next, the burner module 100 according to the embodiment will be further described. FIG. 2 is a front view of the burner module 100, i.e., a diagram showing the burner module 100 as viewed from the combustion chamber 102. As described above, the burner module 100 has a disk shape. Hereinafter, a circumferential direction of the burner module 100 is simply referred to as a “circumferential direction,” and a radial direction of the burner module 100 is simply referred to as a “radial direction.”

As shown in FIG. 2, the burner module 100 according to the embodiment includes: four air guide panels 17 each having an annular shape; and three hydrogen supply rings 18 located between the four air guide panels 17 and each having an annular shape. In FIG. 2, portions shown by diagonal lines are the hydrogen supply rings 18. The air guide panels 17 and the hydrogen supply rings 18 share the same center but have different diameters. The air supplied to the burner module 100 is supplied to back surfaces (surfaces at the front side) of the air guide panels 17. Moreover, the hydrogen supplied through the hydrogen supply pipe 109 (see FIG. 1) to the burner module 100 is supplied to the hydrogen supply rings 18.

Furthermore, the burner module 100 includes six burner rings 11 to 16. These burner rings 11 to 16 share the same center but have different diameters. Hereinafter, the burner rings 11 to 16 are referred to as a first burner ring 11, a second burner ring 12, a third burner ring 13, a fourth burner ring 14, a fifth burner ring 15, and a sixth burner ring 16 in descending order of diameter.

The burner module 100 according to the embodiment includes four air guide panels 17, three hydrogen supply rings 18, and six burner rings 11 to 16. However, the number of air guide panels 17, the number of hydrogen supply rings 18, and the number of burner rings 11 to 16 in the burner module 100 are not limited.

Burner Ring

Next, the above burner rings 11 to 16 will be further described. Each of the burner rings 11 to 16 includes micro burners 20 lined up in an annular shape. In other words, each of the burner rings 11 to 16 is formed by the micro burners 20 lined up in the annular shape. Each of the micro burners 20 can mix the hydrogen and the air to generate the fuel-air mixture including the hydrogen and the air and can discharge the fuel-air mixture toward the combustion chamber 102.

FIG. 3 is an enlarged view of a part of the burner module 100 shown in FIG. 2. The upper side on the paper surface of FIG. 3 is an outside in the radial direction, and the lower side on the paper surface of FIG. 3 is an inside in the radial direction. FIG. 3 is an enlarged view of a part of the first burner ring 11 and a part of the second burner ring 12. Moreover, FIG. 4 is a sectional view taken along line IV-IV of FIG. 3. The upper side on the paper surface of FIG. 4 is the outside in the radial direction, the lower side on the paper surface of FIG. 4 is the inside in the radial direction, the left side on the paper surface of FIG. 4 is the front side, and the right side on the paper surface of FIG. 4 is the rear side.

As shown in FIG. 3, each of the micro burners 20 includes an air passage 21 and a hydrogen injection hole 22.

The air passages 21 are passages through which the air flows. In the embodiment, the air guide panel 17 includes air holes 23, and the air holes 23 define the air passages 21. The shape of the air hole 23 is not limited. For example, the air guide panel 17 and the hydrogen supply ring 18 may be located with a gap in the radial direction, and the gap may communicate with the air holes 23. As shown in FIG. 4, the air supplied to the back surfaces of the air guide panels 17 flows through the air passages 21 toward the rear side along a direction (axial direction of the combustor 101) perpendicular to the radial direction, i.e., toward the combustion chamber 102.

The hydrogen injection holes 22 are holes that inject the hydrogen. As shown in FIG. 3, the hydrogen injection holes 22 are located at the hydrogen supply ring 18 and at the same circumferential positions as centers of the corresponding air passages 21. As shown in FIG. 4, a hydrogen supply passage 24 is defined in the hydrogen supply ring 18, and the hydrogen supplied through the hydrogen supply pipe 109 (see FIG. 1) flows through the hydrogen supply passage 24 to the circumferential positions. The hydrogen injection holes 22 extend from the hydrogen supply passage 24 in the radial direction and inject the hydrogen in the radial direction from the hydrogen supply passage 24.

Moreover, the hydrogen injection hole 22 of the embodiment is located behind the air passage 21. To be specific, the hydrogen injection hole 22 is located downstream of the air passage 21 in the flow direction of the air. Therefore, the hydrogen injection hole 22 injects the hydrogen into the air, which has flowed through the air passage 21, in a direction intersecting with the flow of the air. However, the hydrogen injection hole 22 may inject the hydrogen into the air, which has not yet flowed through the air passage 21, in the direction intersecting with the flow of the air. In the embodiment, the hydrogen injection hole 22 injects the hydrogen in the direction orthogonal to the flow of the air. However, the hydrogen injection hole 22 does not necessarily have to inject the hydrogen in the direction orthogonal to the flow of the air. For example, the hydrogen injection hole 22 may inject the hydrogen in a direction between a direction inclined by 10° toward the upstream side from the direction orthogonal to the flow of the air and a direction inclined by 20° toward the downstream side from the direction orthogonal to the flow of the air.

The foregoing has described the micro burner 20 mainly with reference to the micro burner 20 of the first burner ring 11. Each of the micro burners 20 of the burner rings 12 to 16 is basically the same in configuration as the micro burner 20 of the first burner ring 11. However, the hydrogen injection holes 22 of the micro burners 20 of the first burner ring 11, the third burner ring 13, and the fifth burner ring 15 inject the hydrogen toward the “outside” in the radial direction, and the hydrogen injection holes 22 of the micro burners 20 of the second burner ring 12, the fourth burner ring 14, and the sixth burner ring 16 inject the hydrogen toward the “inside” in the radial direction.

As described above, since the burner module 100 according to the embodiment includes a large number of micro burners 20, the fuel-air mixture including the hydrogen and the air can be discharged in a dispersed manner. In addition, since the hydrogen is injected in the direction intersecting with the flow of the air, the mixing of the hydrogen and the air is promoted. Therefore, according to the burner module 100 of the embodiment, local high-temperature combustion can be suppressed, and therefore, the generation of NOx can be suppressed. Moreover, since the hydrogen injection hole 22 injects the hydrogen into the air which has flowed through the air passage 21, flashback can also be suppressed.

In the embodiment, the burner rings 11 to 16 that discharge the fuel-air mixture may be selected in accordance with an operating state of the gas turbine engine including the combustor 101, i.e., in accordance with the amount of fuel-air mixture discharged from the entire burner module 100. For example, at the start of the gas turbine engine, the fuel-air mixture may be discharged from the first burner ring 11 and the second burner ring 12, and the fuel-air mixture may not be discharged from the other burner rings 11 to 14. On the other hand, under high load of the gas turbine engine, the fuel-air mixture may be discharged from all of the burner rings 11 to 16.

Irregular Burner Ring

Next, an irregular burner ring will be described. When the micro burners 20 are located in an annular shape as in the embodiment, combustion oscillations may occur by the movement of a large flame portion in the circumferential direction. In the embodiment, to suppress the combustion oscillations, at least one of the burner rings 11 to 16 is the irregular burner ring.

Herein, the “irregular burner ring” denotes a burner ring in which regular regions 31 and irregular regions 32 are alternately lined up in the circumferential direction. As shown in FIG. 2, in the embodiment, the first burner ring 11, the second burner ring 12, the third burner ring 13, and the fourth burner ring 14 include the irregular regions 32, and therefore correspond to the irregular burner rings. Moreover, the irregular region 32 denotes a region where the amount of fuel-air mixture discharged per unit area (hereinafter referred to as a “discharge density”) is smaller than that of the regular region 31.

In the embodiment, the micro burners 20 are located in the regular region 31 at regular intervals in the circumferential direction, but the micro burners 20 are not located in the irregular region 32. To be specific, a region where the micro burner 20 is located is the regular region 31, and a region where the micro burner 20 is not located is the irregular region 32. Therefore, the discharge density in the irregular region 32 can be made lower than the discharge density in the regular region 31. However, the micro burners 20 may be located in both of the irregular region 32 and the regular region 31, and the amount of fuel-air mixture discharged from the micro burners 20 located in the irregular region 32 may be made smaller than the amount of fuel-air mixture discharged from the micro burners 20 located in the regular region 31. Even in this case, the discharge density in the irregular region 32 can be made lower than the discharge density in the regular region 31.

As described above, the irregular burner ring includes the irregular region 32 whose discharge density is low. Therefore, even if the large flame portion is generated in the burner module 100, the large flame portion cannot cross the irregular region 32 or move in the circumferential direction. As a result, the combustion oscillations of the burner module 100 can be suppressed. As described above, in the embodiment, at least one of the burner rings 11 to 16 included in the burner module 100 is the irregular burner ring. However, all of the burner rings 11 to 16 may be the irregular burner rings. Moreover, only one of the burner rings 11 to 16 included in the burner module 100 may be the irregular burner ring.

Furthermore, as shown in FIG. 3, an irregular distance X is longer than a regular distance Y. The irregular distance X is a center-to-center distance between the adjacent micro burners 20 sandwiching the irregular region 32. The regular distance Y is a center-to-center distance between the micro burners 20 adjacent to each other in the regular region 31. For example, the irregular distance X in each irregular burner ring may be at least twice and at most ten times as long as the regular distance Y. When the irregular distance X is set to at least twice as long as the regular distance Y, the movement of the large flame portion can be effectively prevented. Moreover, when the irregular distance X in each irregular burner ring is set to at most ten times as long as the regular distance Y, the required amount of fuel-air mixture to be discharged can be secured.

Furthermore, as shown in FIG. 2, the first burner ring 11 includes the irregular regions 32, and some of the circumferential positions of the irregular regions 32 of the first burner ring 11 overlap the circumferential positions of the irregular regions 32 of the third burner ring 13. Similarly, the second burner ring 12 includes the irregular regions 32, and some of the circumferential positions of the irregular regions 32 of the second burner ring 12 overlap the circumferential positions of the irregular regions 32 of the fourth burner ring 14. As above, when the circumferential positions of the irregular regions 32 of the large-diameter burner rings 11 and 12 and the circumferential positions of the irregular regions 32 of the small-diameter burner rings 13 and 14 overlap each other, the movement of the large flame portion can be effectively prevented.

In the embodiment, some of the irregular regions 32 of the first burner ring 11 and all of the irregular regions 32 of the third burner ring 13 overlap each other in the circumferential direction. However, some of the irregular regions 32 of the first burner ring 11 and some of the irregular regions 32 of the third burner ring 13 may overlap each other in the circumferential direction, or all of the irregular regions 32 of the first burner ring 11 and all of the irregular regions 32 of the third burner ring 13 may overlap each other in the circumferential direction. The same applies to the second burner ring 12 and the fourth burner ring 14. Moreover, the irregular regions 32 of all the burner rings 11 to 14 that are the irregular burner rings may overlap each other in the circumferential direction, i.e., may be located at the same circumferential positions.

Furthermore, a ratio of the irregular regions 32 to an entire circumferential region in each of the burner rings 11 to 14 that are the irregular burner rings may be 10% or more and 50% or less. In the embodiment, the ratio of the irregular regions 32 to the entire circumferential region in each of the first burner ring 11 and the second burner ring 12 is 50%, and the ratio of the irregular regions 32 to the entire circumferential region in each of the third burner ring 13 and the fourth burner ring 14 is 10%.

When the ratio of the irregular regions 32 to the entire circumferential region in the irregular burner ring is set to 10% or more, the movement of the large flame portion can be effectively prevented. Moreover, when the ratio of the irregular regions 32 to the entire circumferential region in the irregular burner ring is set to 50%, the required amount of fuel-air mixture to be discharged can be secured.

Furthermore, as described above, the ratio of the irregular regions 32 to the entire circumferential region in each of the first burner ring 11 and the second burner ring 12 that are the large-diameter burner rings is 50% and is higher than 10% that is the ratio of the irregular regions 32 to the entire circumferential region in each of the third burner ring 13 and the fourth burner ring 14 that are the small-diameter burner rings. According to this configuration, since the outer circumference of the large-diameter burner ring is long, the ratio of the irregular regions 32 to the entire circumferential region in the burner ring can be finely adjusted.

Conclusion

A first aspect disclosed in the present specification is a burner module including burner rings that share the same center but have different diameters, wherein: each of the burner rings includes micro burners that are lined up in an annular shape and discharge a fuel-air mixture including hydrogen and air; each of the micro burners includes an air passage through which the air flows and a hydrogen injection hole that injects the hydrogen into the air which has flowed through the air passage or the air which has not yet flowed through the air passage, in a direction intersecting with a flow direction of the air; at least one of the burner rings is an irregular burner ring; the irregular burner ring includes regular regions and irregular regions which are alternately lined up in a circumferential direction; and the amount of fuel-air mixture discharged per unit area in the irregular region is smaller than the amount of fuel-air mixture discharged per unit area in the regular region.

According to this configuration, the hydrogen is injected into the air which has flowed through the air passage, in the direction intersecting with the flow direction of the air. Therefore, the flashback can be prevented while suppressing the generation of NOx. Moreover, since at least one of the burner rings is the irregular burner ring, the movement of the large flame portion in the circumferential direction can be prevented, and therefore, the combustion oscillations can be suppressed.

A second aspect disclosed in the present specification is the burner module according to the first aspect, wherein: the micro burners are located in the regular regions; and the micro burners are not located in the irregular regions.

According to this configuration, the irregular region can be easily formed.

A third aspect disclosed in the present specification is the burner module according to the second aspect, wherein an irregular distance that is a center-to-center distance between the adjacent micro burners sandwiching the irregular region is longer than a regular distance that is a center-to-center distance between the micro burners adjacent to each other in the regular region ..

According to this configuration, the movement of the large flame portion in the circumferential direction can be effectively prevented, and therefore, the combustion oscillations can be effectively suppressed.

A fourth aspect disclosed in the present specification is the burner module according to the third aspect, wherein the irregular distance is at least twice and at most ten times as long as the regular distance.

According to this configuration, the required amount of fuel-air mixture to be discharged can be secured while preventing the movement of the large flame portion.

A fifth aspect disclosed in the present specification is the burner module according to any one of the first to fourth aspects, wherein a ratio of the irregular regions to an entire circumferential region in the irregular burner ring is 10% or more and 50% or less.

According to this configuration, the required amount of fuel-air mixture to be discharged can be secured while preventing the movement of the large flame portion.

A sixth aspect disclosed in the present specification is the burner module according to any one of the first to fifth aspects, wherein: the burner rings include a large-diameter burner ring that is an irregular burner ring and a small-diameter burner ring that is the irregular burner ring and smaller in diameter than the large-diameter burner ring; and a circumferential position of at least one of the irregular regions of the large-diameter burner ring overlaps a circumferential position of at least one of the irregular regions of the small-diameter burner ring.

According to this configuration, the movement of the large flame portion can be effectively prevented.

A seventh aspect disclosed in the present specification is the burner module according to any one of the first to sixth aspects, wherein: the burner rings include a large-diameter burner ring that is an irregular burner ring and a small-diameter burner ring that is the irregular burner ring and smaller in diameter than the large-diameter burner ring; and a ratio of the irregular regions to an entire circumferential region in the large-diameter burner ring is higher than a ratio of the irregular regions to an entire circumferential region in the small-diameter burner ring.

According to this configuration, the ratio of the irregular regions to the entire circumferential region in the burner ring can be finely adjusted.

Reference Signs List

• • 11 first burner ring
  • 12 second burner ring
  • 13 third burner ring
  • 14 fourth burner ring
  • 15 fifth burner ring
  • 16 sixth burner ring
  • 20 micro burner
  • 21 air passage
  • 22 hydrogen injection hole
  • 31 regular region
  • 32 irregular region
  • 100 burner module

Claims

1. A burner module comprising burner rings that share the same center but have different diameters, wherein:

each of the burner rings includes micro burners that are lined up in an annular shape and discharge a fuel-air mixture including hydrogen and air;

each of the micro burners includes an air passage through which the air flows and a hydrogen injection hole that injects the hydrogen into the air which has flowed through the air passage or the air which has not yet flowed through the air passage, in a direction intersecting with a flow direction of the air;

at least one of the burner rings is an irregular burner ring;

the irregular burner ring includes regular regions and irregular regions which are alternately lined up in a circumferential direction; and

the amount of fuel-air mixture discharged per unit area in the irregular region is smaller than the amount of fuel-air mixture discharged per unit area in the regular region.

2. The burner module according to claim 1, wherein:

the micro burners are located in the regular regions; and

the micro burners are not located in the irregular regions.

3. The burner module according to claim 2, wherein an irregular distance that is a center-to-center distance between the adjacent micro burners sandwiching the irregular region is longer than a regular distance that is a center-to-center distance between the micro burners adjacent to each other in the regular region.

4. The burner module according to claim 3, wherein the irregular distance is at least twice and at most ten times as long as the regular distance.

5. The burner module according to claim 1, wherein a ratio of the irregular regions to an entire circumferential region in the irregular burner ring is 10% or more and 50% or less.

6. The burner module according to claim 1, wherein:

the burner rings include a large-diameter burner ring that is an irregular burner ring and a small-diameter burner ring that is the irregular burner ring and smaller in diameter than the large-diameter burner ring; and

a circumferential position of at least one of the irregular regions of the large-diameter burner ring overlaps a circumferential position of at least one of the irregular regions of the small-diameter burner ring.

7. The burner module according to claim 1, wherein:

the burner rings include a large-diameter burner ring that is an irregular burner ring and a small-diameter burner ring that is the irregular burner ring and smaller in diameter than the large-diameter burner ring; and

a ratio of the irregular regions to an entire circumferential region in the large-diameter burner ring is higher than a ratio of the irregular regions to an entire circumferential region in the small-diameter burner ring.