Nozzle unit, combustor, and power generation device

Abstract

A nozzle unit according to the present disclosure is included in a combustor, a plurality of ejection port groups including a first ejection port for ejecting fuel gas and a second ejection port for ejecting oxidant gas being formed on a combustion chamber-side surface of the combustor, and the plurality of ejection port groups being disposed at positions such that flames generated by combustion of the fuel gas ejected from all of the ejection port groups interfere with each other.

Description

Nozzle unit, combustor, and power generation device

[0001] The present disclosure relates to a nozzle unit, a combustor, and a power generation device.

[0002] There is a social demand for an electric power supply that meets demand. In gas turbine power generation systems that generate electricity by rotating a turbine with combustion gas obtained by burning fuel gas, there is a demand for accurate combustion control in order to generate electricity that meets demand.

[0003] A combustor capable of precisely controlling the combustion of fuel gas is disclosed, for example, in Patent Document 1. Patent Document 1 discloses a gas turbine in which the injection direction of a portion of the gas fuel is oriented in a direction intersecting the direction of air as an oxidizer, and the injection direction of a portion of the gas fuel is oriented in a direction not intersecting the direction of the air. According to Patent Document 1, a favorable combustion state can be achieved by intentionally creating a region in which the gas fuel and air are mixed immediately after injection and a region in which they are not.

[0004] International Publication No. 2023 / 053605

[0005] One way to generate higher power output is to increase the thermal power of the combustor. One way to increase the thermal power of the combustor is to group multiple burners in the combustor together to form a burner assembly.

[0006] In a combustor equipped with a burner assembly, flames from multiple burners overlap within the combustion chamber, thereby generating a large amount of heat. However, if there are regions where the flames from multiple burners overlap and regions where they do not, the combustion state may vary depending on the region within the combustion chamber. For example, the flame from a burner located at the end of the multiple burners is less likely to overlap with the flames from other burners, and therefore the flame state is thought to be different from that in the region where the flames overlap.

[0007] When the combustion state differs depending on the region within the combustion chamber, uneven temperature distribution occurs within the combustion chamber, which can reduce combustion efficiency.

[0008] An object of the present disclosure is to provide a nozzle unit capable of improving combustion efficiency by homogenizing the combustion state in a combustor equipped with multiple burners, a combustor, and a power generation device including the combustor.

[0009] A nozzle unit according to one aspect of the present disclosure is a nozzle unit included in a combustor, and a plurality of nozzle groups including a first nozzle for ejecting fuel gas and a second nozzle for ejecting oxidizer gas are formed on a surface of the combustor facing the combustion chamber, and the plurality of nozzle groups are arranged in positions where flames generated by combustion of the combustion gas ejected from all of the nozzle groups interfere with each other.

[0010] A combustor according to one aspect of the present disclosure includes the nozzle unit described above, a combustion chamber, a fuel supply mechanism that supplies the fuel gas to the first nozzle, and an oxidizer supply mechanism that supplies the oxidizer gas to the second nozzle.

[0011] A power generation device according to one aspect of the present disclosure includes the above-described combustor, a turbine rotated by combustion gas generated by combustion of the fuel gas in the combustion chamber, and a generator that generates electricity using the rotational force of the turbine.

[0012] According to the present disclosure, it is possible to suppress the occurrence of misfires and backfires and improve the turndown ratio.

[0013] FIG. 1 is a diagram showing an example of the configuration of a power generation device according to an embodiment of the present disclosure; FIG. 2 is a diagram showing an example of the configuration of a combustor; FIG. 3 is a diagram for explaining one nozzle group; FIG. 4 is a block diagram for schematically explaining the structure of a nozzle unit; FIG. 5 is a diagram for explaining a first example of arrangement of multiple nozzle groups on the surface of a nozzle unit according to an embodiment of the present disclosure;

[0014] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. However, more detailed explanation than necessary, such as detailed explanation of already well-known matters and redundant explanation of substantially the same configuration, may be omitted.

[0015] <Power Generation Device 100> Fig. 1 is a diagram illustrating an example of the configuration of a power generation device 100 according to an embodiment of the present disclosure. The power generation device 100 includes a combustor 10, a turbine 20, and a generator 30. Note that, although Fig. 1 illustrates the combustor 10, the turbine 20, and the generator 30 as being independent of one another, in reality, these components may be integrated to form the power generation device 100.

[0016] Fuel gas and oxidant gas are supplied to the combustor 10. The combustor 10 mixes and burns the fuel gas and the oxidant gas, and supplies the combustion gas to the turbine 20.

[0017] The turbine 20 is rotated by the combustion gas and supplies rotational power to the generator 30 .

[0018] The generator 30 generates electricity using the rotational power. The electricity generated by the generator 30 is supplied to an external source (for example, a power grid or a device that operates on electricity).

[0019] <Combustor 10> Fig. 2 is a diagram illustrating an example of the configuration of the combustor 10. In the example illustrated in Fig. 2, the combustor 10 includes a nozzle unit 11, a combustor liner 12, and a combustor case 13.

[0020] The nozzle unit 11 is a unit that injects fuel gas and oxidizer gas supplied to the combustor 10 into a combustion chamber C formed by the combustor liner 12. The fuel gas is, for example, hydrogen gas. The oxidizer gas is, for example, oxygen gas. The nozzle unit 11 may also inject a cooling gas into the combustion chamber C along with the fuel gas and the oxidizer gas. The cooling gas is, for example, water vapor. In the following description, the surface of the plate-shaped member (nozzle plate) that constitutes the nozzle unit 11 that faces the combustion chamber C will be referred to as surface 11S.

[0021] The fuel gas is not limited to hydrogen gas, but may be natural gas or synthetic methane gas, for example. The oxidant gas is not limited to oxygen gas, but may be air, for example, although oxygen gas is preferable from the viewpoint of reducing NOx. The cooling gas is not limited to water vapor gas, but may be air.

[0022] The combustor liner 12 is a container that constitutes the combustion chamber C. In the example shown in Fig. 2, the combustor liner 12 has a cylindrical shape. The nozzle unit 11 is disposed on one bottom surface of the combustor liner 12, and the other bottom surface is connected to the turbine 20 (see Fig. 1).

[0023] The combustor case 13 is a container that houses the nozzle unit 11 and the combustor liner 12. In the example shown in Fig. 2, the combustor case 13 has a cylindrical shape.

[0024] A cooling gas (e.g., steam) is supplied to one bottom surface of the combustor case 13 to be supplied to the combustion chamber C of the combustor liner 12. A plurality of inlet holes 14 are formed in the wall surface of the combustor liner 12, and the cooling gas supplied to the combustor case 13 flows into the combustion chamber C through the inlet holes 14.

[0025] In the combustion chamber C, the fuel gas and oxidizer gas ejected from the nozzle unit 11 are mixed and ignited, thereby causing combustion. As the fuel gas and oxidizer gas are ejected from the nozzle unit 11 with great force, a flame is generated at a position some distance from the nozzle unit 11. This prevents the nozzle unit 11 from being burned by the flame. In addition, the nozzle unit 11 is also prevented from being burned by the cooling gas ejected from the surface of the nozzle unit 11 facing the combustion chamber C. In addition, the cooling gas flowing in from the inlet holes 14 prevents the inner surface of the combustor liner 12 from being burned.

[0026] <Nozzle unit 11> The following describes the nozzle unit 11. A surface 11S of the nozzle unit 11 is provided with a plurality of nozzle groups 40, each including a first nozzle 41 for ejecting fuel gas and a second nozzle 42 for ejecting oxidant gas. The nozzle groups 40 correspond to burners in a typical combustor.

[0027] 3 is a diagram for explaining one of the nozzle groups 40. In FIG. 3, one of the nozzle groups 40 arranged on the surface 11S of the nozzle unit 11 is shown in an enlarged view.

[0028] The nozzle group 40 is configured by arranging one first nozzle 41 and two second nozzles 42 along the arrangement direction Da. The first nozzle 41 is located in the center of the two second nozzles 42.

[0029] The first nozzle 41 is a nozzle for ejecting fuel gas, and the second nozzle 42 is a nozzle for ejecting oxidant gas.

[0030] A specific example of the arrangement of the plurality of nozzle groups 40 on the surface 11S of the nozzle unit 11 will be described in detail later.

[0031] Fig. 4 is a block diagram that schematically illustrates the structure of the nozzle unit 11. As shown in Fig. 4, the nozzle unit 11 includes a fuel gas storage section 51, an oxidizing gas storage section 52, a fuel gas supply mechanism 53, and an oxidizing gas supply mechanism 54.

[0032] The fuel gas storage unit 51 is a type of tank that stores fuel gas supplied from outside the combustor 10, and is provided inside the nozzle unit 11. The fuel gas supply mechanism 53 supplies the fuel gas stored in the fuel gas storage unit 51 to the first nozzle 41 through the fuel gas flow path. However, the present disclosure is not limited to this, and the fuel gas storage unit may be provided outside the nozzle unit. The shape of the fuel gas flow path may be configured as a straight line or a curved line.

[0033] The oxidant gas storage unit 52 is a type of tank that stores oxidant gas supplied from outside the combustor 10, and is provided inside the nozzle unit 11. The oxidant gas supply mechanism 54 supplies the oxidant gas stored in the oxidant gas storage unit 52 to the second nozzle 42 through the oxidant gas flow path. However, the present disclosure is not limited to this, and the oxidant gas storage unit may be provided outside the nozzle unit. The shape of the oxidant gas flow path may be configured as a straight line or a curved line.

[0034] It is desirable that the fuel gas storage section 51 that stores the fuel gas and the oxygen-containing gas storage section 52 that stores the oxygen-containing gas have different depths, i.e., different distances from the surface 11S. With this configuration, even if the distance d1 between the nozzle groups 40 in the arrangement direction Da is reduced, the fuel gas storage section 51 and the oxygen-containing gas storage section 52 can be arranged so as not to overlap each other. This allows the nozzle unit 11, and therefore the combustor 10, to be made smaller.

[0035] In order to equalize the flow rate and velocity of the fuel gas ejected from the two second ejection ports 42 included in one ejection port group 40 and to equalize the pressure loss, it is desirable that the dimensions and shape of the oxidant gas flow paths connecting the oxidant gas storage section 52 and the two second ejection ports 42 be the same. Furthermore, if the flow paths are close to each other, the flows may interfere with each other, so it is desirable to arrange the flow paths at a certain distance from each other, for example by configuring the flow paths in a curve.

[0036] 5 is a diagram schematically illustrating the shape of a flame F generated by combustion of gas ejected from one nozzle group 40. FIG. 5 shows the surface 11S of the nozzle unit 11 and the flame F as viewed from the combustion chamber C. In this embodiment, as shown in FIG. 5, the flame F generated by combustion of fuel gas ejected from one nozzle group 40 spreads more widely along a direction Db perpendicular to the arrangement direction Da than along the arrangement direction Da. For example, a flame of this shape can be generated by adjusting at least one of the positions of the first nozzles 41 and the second nozzles 42 in the nozzle group 40, the ejection speed or ejection direction of the gas ejected from each nozzle, etc.

[0037] In the following description, for the sake of simplicity, a flame generated by the combustion of fuel gas ejected from one of the nozzle groups 40 may be referred to as a flame generated by the nozzle group 40.

[0038] Next, the arrangement of the plurality of nozzle groups 40 on the surface 11S of the nozzle unit 11 will be described.

[0039] <First Arrangement Example> Fig. 6 is a diagram for explaining a first arrangement example of the plurality of ejection port groups 40 on the surface 11S of the nozzle unit 11 according to the embodiment of the present disclosure. Fig. 6 shows the surface 11S as viewed from the front.

[0040] 6 , a plurality of nozzle groups 40 are arranged side by side in a spiral shape. More specifically, among the nozzles included in one nozzle group 40, a first nozzle 41 that ejects fuel gas is arranged on a curve Cs of the spiral shape, and two second nozzles 42 are arranged at positions symmetrical to each other with respect to the curve Cs. As a result, a given nozzle group 40 is arranged such that the arrangement direction of the first nozzles 41 and the second nozzles 42 included in that nozzle group 40 is approximately perpendicular to the curve Cs of the spiral shape.

[0041] 6, the spiral curve Cs is shown as a shaded area, and the first jet nozzle 41 is located within that area. Note that the area corresponding to the curve Cs in FIG. 6 is shown for the purpose of explaining the spiral shape, and is not a shape that is actually formed on the surface 11S of the nozzle unit 11.

[0042] In Fig. 6, one nozzle group 40 is shown surrounded by an oval dashed line. The number of nozzle groups 40 provided on the surface 11S of one nozzle unit 11 is not limited to the example shown in Fig. 6, and may be more or less.

[0043] The distance d4 between adjacent first nozzles 41 on the curve Cs is set to a distance that causes interference between flames generated by combustion of fuel gas ejected from the respective first nozzles 41. When the surface 11S of the nozzle unit 11 has a circular shape with a diameter of 40 mm, d4 is set to, for example, 3 mm, preferably in the range of 2 mm to 15 mm. Note that the distances between all of the nozzle groups 40 arranged on the surface 11S do not have to be the same.

[0044] Fig. 7 is a schematic diagram showing a state in which flames are generated from all of the nozzle groups 40 in the first arrangement example of the nozzle groups 40. In Fig. 7, the flame F generated by the first nozzles 41 is shown by a schematic elliptical solid line.

[0045] As shown in Fig. 5, the flame F generated by one nozzle group 40 extends in a direction perpendicular to the arrangement direction of the nozzles in the nozzle group 40. As shown in Fig. 6, in the first arrangement example, the multiple nozzle groups 40 are arranged so that the arrangement direction of the included nozzles is approximately perpendicular to the spiral curve Cs. As a result, as shown in Fig. 7, in the first arrangement example, the flames generated by adjacent nozzle groups 40 interfere with each other, and ultimately the flames F generated by all the nozzle groups 40 interfere with each other. In this specification, the term "interference between flames" means that the flames mutually influence each other through heat or gas flow, thereby strengthening the flames, and corresponds to a state in which portions of the flames appear to be in contact with each other.

[0046] As described above, in the first arrangement example of the nozzle groups 40 provided on the surface 11S of the nozzle unit 11, the flames F generated by all of the nozzle groups 40 interfere with each other, thereby stabilizing the combustion state in the combustion chamber C of the combustor 10. This eliminates temperature variations in the combustion chamber C and improves combustion efficiency.

[0047] Furthermore, even if there are individual differences among the multiple nozzle groups 40 and differences in the size of the flame generated by each nozzle group 40, the flames F generated by all the nozzle groups 40 interfere with each other, so that the individual differences can be absorbed in the overall flame generated within the combustion chamber C.

[0048] Furthermore, in the first arrangement example, the nozzle group 40 is arranged in a spiral shape, which allows for easy scaling up of the nozzle unit 11 if desired. When the nozzle groups are arranged in a row, flames interfere with each other except at both ends of the row, but flames do not interfere with each other at both ends of the row. If a nozzle unit having a nozzle row in which nozzle groups are arranged in a row is scaled up, for example, by arranging the nozzle rows perpendicular to the row direction and arranging the nozzle groups in a matrix format, many nozzle groups will be located at the ends, which will increase the frequency of temperature variation and reduce combustion efficiency. When scaling up the first arrangement example, by arranging new nozzle groups 40 on an extension of the spiral shape, a scaled-up nozzle unit 11 can be easily designed without increasing the number of nozzle groups at both ends. This allows for the provision of a nozzle unit 11 with reduced temperature variation and improved combustion efficiency.

[0049] Furthermore, when it becomes necessary to change the distance between the nozzle groups 40, the nozzle unit 11 can be easily designed with a changed distance between the nozzle groups 40 by enlarging or reducing the entire collection of the nozzle groups 40 arranged in a spiral shape. By patterning the design so that the arrangement of the multiple nozzle groups 40 is in a spiral shape, it becomes easy to newly design the surface 11S of the nozzle unit 11.

[0050] <Second Arrangement Example> Fig. 8 is a diagram for explaining a second example of the arrangement of the plurality of ejection port groups 40 on the surface 11S of the nozzle unit 11 according to the embodiment of the present disclosure. Fig. 8 shows the surface 11S as viewed from the front.

[0051] 8 , in the second arrangement example, the multiple nozzle groups 40 are arranged so that they are located on different sides of multiple equilateral triangles. That is, the nozzle groups 40 are arranged so that their arrangement direction is parallel to the sides of the equilateral triangles. Note that the first nozzles 41 included in one nozzle group 40 are located at the midpoints of the sides of the equilateral triangles.

[0052] In Figure 8, an equilateral triangle with multiple nozzle groups 40 arranged on each side is shown by dashed lines, but these dashed lines are shown to explain the arrangement positions of the nozzle groups 40 and are not the shape formed on the actual surface 11S of the nozzle unit 11.

[0053] The number of nozzle groups 40 provided on the surface 11S of one nozzle unit 11 is not limited to the example shown in FIG. 8, and may be greater or less.

[0054] 9 is a schematic diagram showing a state in which flames are generated from all of the nozzle groups 40 in the second arrangement example of the nozzle groups 40. In FIG. 9, the flames F generated by the first nozzles 41 are shown by a schematic elliptical solid line.

[0055] As shown in Fig. 5, the flame F generated by one nozzle group 40 extends in a direction perpendicular to the arrangement direction of the nozzles in the nozzle group 40. Then, as shown in Fig. 8, in the second arrangement example, the multiple nozzle groups 40 are arranged so that the arrangement directions of the included nozzles are parallel to the sides of an equilateral triangle and the first nozzle 41 is located at the midpoint of the side. As a result, as shown in Fig. 9, in the second arrangement example, the flames generated by adjacent nozzle groups 40 interfere with each other, and ultimately the flames F generated by all of the nozzle groups 40 interfere with each other.

[0056] As described above, in the second arrangement example of the nozzle port groups 40 provided on the surface 11S of the nozzle unit 11, the flames F generated by all of the nozzle port groups 40 interfere with each other, thereby stabilizing the combustion state in the combustion chamber C of the combustor 10. This eliminates temperature variations in the combustion chamber C and improves combustion efficiency.

[0057] Furthermore, even if there are individual differences, such as differences in the size of the flames generated, among the multiple nozzle groups 40, the flames F generated by all of the nozzle groups 40 interfere with each other, so that the individual differences can be absorbed in the overall flame generated within the combustion chamber C.

[0058] Furthermore, for example, if it becomes necessary to scale up the nozzle unit 11, new nozzle groups 40 can be arranged on the sides of an equilateral triangle adjacent to the equilateral triangle corresponding to the arrangement of the nozzle groups 40 already arranged. This makes it easy to design a scaled-up nozzle unit 11 without increasing the number of ends where flames do not interfere with each other. If it becomes necessary to change the distance between the nozzle groups 40, the nozzle unit 11 can be easily designed with a changed distance between the nozzle groups 40 by enlarging or reducing the size of the equilateral triangle on each side of which the nozzle groups 40 are arranged. By patterning the design so that multiple nozzle groups 40 are arranged on the sides of an equilateral triangle, it becomes easy to newly design the surface 11S of the nozzle unit 11.

[0059] The disclosures of the specification, drawings and abstract contained in Japanese Patent Application No. 2024-051820, filed on March 27, 2024, are incorporated herein by reference in their entirety.

[0060] The present disclosure is useful for nozzle units used in combustors of turbine power generation devices.

[0061] REFERENCE SIGNS LIST 100 Power generation device 10 Combustor 11 Nozzle unit 11S Surface 12 Combustor liner 13 Combustor case 14 Inlet hole 20 Turbine 30 Generator 40 Group of nozzles 41 First nozzle 42 Second nozzle 51 Fuel gas storage section 52 Oxidant gas storage section 53 Fuel gas supply mechanism 54 Oxidant gas supply mechanism

Claims

1. A nozzle unit included in a combustor, wherein a plurality of nozzle groups including a first nozzle for ejecting fuel gas and a second nozzle for ejecting oxidizer gas are formed on a surface of the combustor facing the combustion chamber, and the plurality of nozzle groups are arranged in positions where flames generated by combustion of the fuel gas ejected from all of the nozzle groups interfere with each other.

2. The nozzle unit according to claim 1, wherein the group of nozzles has two second nozzles arranged at positions that are point symmetrical with respect to the center of one first nozzle.

3. The nozzle unit according to claim 2, wherein the first nozzles of the group of multiple nozzles are arranged on a spiral curve when the surface is viewed from the front.

4. The nozzle unit according to claim 2, wherein the plurality of nozzle groups are arranged so as to be located on different sides of one or more equilateral triangles when the surface is viewed from the front.

5. The nozzle unit according to claim 4, wherein the first nozzle is formed so as to be positioned at the midpoint of the side.

6. A combustor comprising: the nozzle unit according to claim 1; a combustion chamber; a fuel supply mechanism that supplies the fuel gas to the first nozzle; and an oxidizer supply mechanism that supplies the oxidizer gas to the second nozzle.

7. A power generation device comprising: the combustor according to claim 6; a turbine rotated by combustion gas generated by combustion of the fuel gas in the combustion chamber; and a generator that generates electricity by the rotational force of the turbine.

Images