Patent Application
20220214043
This application claims priority to Korean Patent Application No. 10-2021-0001525, filed on Jan. 6, 2021, the disclosure of which is incorporated by reference herein in its entirety.
Apparatuses and methods consistent with exemplary embodiments relate to a fuel nozzle, a fuel nozzle module having the same, and a combustor.
A gas turbine is a power engine configured to mix and combust air compressed by a compressor and fuel and rotate a turbine with a high-temperature gas generated by combustion. The gas turbine is used to drive a generator, an aircraft, a ship, a train, or the like.
The gas turbine includes a compressor, a combustor, and a turbine. The compressor sucks and compresses external air and delivers the compressed air to the combustor. The air compressed by the compressor is in a high-pressure and high-temperature state. The combustor mixes the compressed air compressed by the compressor with fuel and combusts the mixture to produce combustion gas which is discharged to the turbine. A turbine blade in the turbine is rotated by the combusted gas to generate power. The generated power is used in various fields such as power generation and driving of a mechanical device.
Aspects of one or more exemplary embodiments provide a fuel nozzle, a fuel nozzle module having the same, and a combustor, which can be applied to a hydrogen turbine using hydrogen as a main raw material while reducing a manufacturing cost.
Additional aspects will be set forth in part in the description which follows and, in part, will become apparent from the description, or may be learned by practice of the exemplary embodiments.
According to an aspect of an exemplary embodiment, there is provided a fuel nozzle including: a nozzle cylinder having a space through which fuel flows and a plurality of fuel holes through which the fuel flows in a surface; a shroud spaced apart from the nozzle cylinder and formed to surround the nozzle cylinder in a longitudinal direction of the nozzle cylinder; and a mixing flow path formed between the nozzle cylinder and the shroud to mix the fuel supplied through the plurality of fuel holes and compressed air supplied from a compressor.
Each of the plurality of fuel holes can be formed to have the same size, and intervals between the plurality of fuel holes can be formed to be the same.
Each of the plurality of fuel holes can be formed to have the same size, and intervals between the plurality of fuel holes can be formed differently.
Each of the plurality of fuel holes can be formed to have a different size, and intervals between the plurality of fuel holes can be formed to be the same.
Each of the plurality of fuel holes can be formed to have a different size, and intervals between the plurality of fuel holes can be formed differently.
According to an aspect of another exemplary embodiment, there is provided a fuel nozzle module including: a plurality of fuel nozzles, each of the plurality of fuel nozzles includes: a nozzle cylinder having a space through which fuel flows and a plurality of fuel holes through which the fuel flows in a surface; a shroud spaced apart from the nozzle cylinder and formed to surround the nozzle cylinder in a longitudinal direction of the nozzle cylinder; and a mixing flow path formed between the nozzle cylinder and the shroud to mix the fuel supplied through the plurality of fuel holes and compressed air supplied from a compressor, wherein a position of the fuel hole included in at least one of the plurality of fuel nozzles is formed at a position different from that of fuel holes included in the other fuel nozzles.
Each of the plurality of fuel holes can be formed to have the same size, and intervals between the fuel holes can be formed to be the same.
Each of the plurality of fuel holes can be formed to have the same size, and intervals between the plurality of fuel holes can be formed differently.
Each of the plurality of fuel holes can be formed to have a different size, and intervals between the plurality of fuel holes can be formed to be the same.
Each of the plurality of fuel holes can be formed to have a different size, and intervals between the plurality of fuel holes can be formed differently.
At least one of the plurality of fuel nozzles can be formed to have a width of the mixing flow path different from each other.
At least one of the plurality of fuel nozzles can be formed to have a width of the mixing flow path different from each other so that a virtual central axis of the shroud and a virtual central axis of the nozzle cylinder do not coincide with each other.
At least one of the plurality of fuel nozzles can include a mixing flow path having a cross-sectional area different from that of mixing flow paths of other fuel nozzles.
According to an aspect of another exemplary embodiment, there is provided a combustor including: a combustion chamber assembly including a combustion chamber in which fuel fluid is combusted; and a fuel nozzle assembly including a fuel nozzle module including a plurality of fuel nozzles that inject the fuel fluid into the combustion chamber, each of the plurality of fuel nozzles includes: a nozzle cylinder having a space through which fuel flows and a plurality of fuel holes through which the fuel flows in a surface; a shroud spaced apart from the nozzle cylinder and formed to surround the nozzle cylinder in a longitudinal direction of the nozzle cylinder; and a mixing flow path formed between the nozzle cylinder and the shroud to mix the fuel supplied through the plurality of fuel holes and compressed air supplied from a compressor.
Each of the plurality of fuel holes can be formed to have the same size, and intervals between the plurality of fuel holes can be the same or different.
Each of the plurality of fuel holes can be formed to have a different size, and intervals between the plurality of fuel holes can be the same or different.
A position of a fuel hole included in at least one of the plurality of fuel nozzles can be formed at a position different from that of fuel holes included in the other fuel nozzles.
At least one of the plurality of fuel nozzles can be formed to have a width of the mixing flow path different from each other.
At least one of the plurality of fuel nozzles can be formed to have a width of the mixing flow path different from each other so that a virtual central axis of the shroud and a virtual central axis of the nozzle cylinder do not coincide with each other.
At least one of the plurality of fuel nozzles can include a mixing flow path having a cross-sectional area different from that of mixing flow paths of other fuel nozzles.
The above and other aspects will become more apparent from the following description of the exemplary embodiments with reference to the accompanying drawings, in which:
Various modifications and various embodiments will be described below in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the disclosure. It should be understood, however, that the various embodiments are not for limiting the scope of the disclosure to the specific embodiment, but they should be interpreted to include all modifications, equivalents, and alternatives of the embodiments included within the spirit and scope disclosed herein.
The terminology used herein is for the purpose of describing specific embodiments only and is not intended to limit the scope of the disclosure. The singular expressions “a”, “an”, and “the” are intended to include the plural expressions as well unless the context clearly indicates otherwise. In the disclosure, terms such as “comprises”, “includes”, or “have/has” should be construed as designating that there are such features, integers, steps, operations, components, parts, and/or combinations thereof, not to exclude the presence or possibility of adding of one or more of other features, integers, steps, operations, components, parts, and/or combinations thereof.
Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings. It should be noted that like reference numerals refer to like parts throughout the various figures and exemplary embodiments. In certain embodiments, a detailed description of functions and configurations well known in the art may be omitted to avoid obscuring appreciation of the disclosure by a person of ordinary skill in the art. For the same reason, some components may be exaggerated, omitted, or schematically illustrated in the accompanying drawings.
Referring to
A thermodynamic cycle of the gas turbine can ideally comply with the Brayton cycle. The Brayton cycle is composed of four processes including an isentropic compression (i.e., an insulation compression) process, static pressure rapid heat process, isentropic expansion (i.e., an insulation expansion) process, and static pressure heat dissipation process. That is, in the Brayton cycle, thermal energy may be released by combustion of fuel in the static pressure environment after ambient air is sucked and compressed at high pressure, the high-temperature combusted gas is expanded and converted into kinetic energy, and an exhaust gas with remaining energy is emitted to the atmosphere. As such, the Brayton cycle is composed of four processes including compression, heating, expansion, and heat-dissipation.
The gas turbine 1000 employing the Brayton cycle includes the compressor 1100, the combustor 1200, and the turbine 1300. Although the following description will be described with reference to
Referring to
The compressor 1100 may be designed in a form of a centrifugal compressor or an axial compressor, and the centrifugal compressor is applied to a small gas turbine whereas a multistage axial compressor is applied to a large gas turbine illustrated in
The compressor 1100 is driven using a part of the power output from the turbine 1300. To this end, as shown in
The combustor 1200 mixes the compressed air supplied from an outlet of the compressor 110 with fuel to combust the mixture at constant pressure to generate a combustion gas with high energy.
The combustor 1200 is disposed on the downstream of the compressor 1100 and includes a plurality of burner modules 1210 annually disposed around the rotary shaft. Referring to
The gas turbine 1000 may use gas fuel including hydrogen or natural gas, liquid fuel, or a combination thereof. In order to create a combustion environment to reduce the amount of emissions such as carbon monoxide or nitrogen oxides, a gas turbine has a recent tendency to apply a premixed combustion scheme that is advantageous in reducing emissions through lowered combustion temperature and homogeneous combustion even though it is difficult to control the premixed combustion.
For the premix combustion, the compressed air introduced from the compressor 1100 is mixed with fuel in advance in the fuel nozzle assembly 1230, and then enters the combustion chamber 1240. When a premix gas is initially ignited by an igniter and then combustion state is stabilized, the combustion state is maintained by supplying fuel and air.
The fuel nozzle assembly 1230 includes a plurality of fuel nozzles 2000 for injecting fuel fluid, and the fuel nozzle 2000 mixes fuel with air in an appropriate ratio to form a fuel-air mixture having conditions suitable for combustion. The plurality of fuel nozzles 2000 may include a plurality of external fuel nozzles radially disposed around the inner fuel nozzle.
The combustion chamber assembly 1220 includes the combustion chamber 1240 in which combustion occurs, a liner 1250 and a transition piece 1260.
The liner 1250 disposed on a downstream side of the fuel nozzle assembly 1230 may have a dual structure of an inner liner 1251 and an outer liner 1252 in which the inner liner 1251 is surrounded by the outer liner 1252. In this case, the inner liner 1251 is a hollow tubular member, and an internal space of the inner liner 1251 forms the combustion chamber 1240. The inner liner 1251 is cooled by the compressed air introduced into an annular space inside the outer liner 1252.
The transition piece 1260 is disposed on a downstream side of the liner 1250 to guide the combustion gas generated in the combustion chamber 1240 to the turbine 1300. The transition piece 1260 may have a dual structure of an inner transition piece 1261 and an outer transition piece 1262 in which the inner transition piece 1261 is surrounded by the outer transition piece 1262. The inner transition piece 1261 is also formed of a hollow tubular member such that a diameter gradually decreases from the liner 1250 toward the turbine 1300. In this case, the inner liner 1251 and the inner transition piece 1261 can be coupled to each other by a plate spring seal. Because respective ends of the inner liner 1251 and the inner transition piece 1261 are fixed to the combustor 1200 and the turbine 1300, respectively, the plate spring seal may have a structure capable of accommodating expansion of length and diameter by thermal expansion to support the inner liner 1251 and the inner transition piece 1261.
As such, the inner liner 1251 and the inner transition piece 1261 have a structure surrounded by the outer liner 1252 and the outer transition piece 1262, respectively, so that the compressed air may flow into the annular space between the inner liner 1251 and the outer liner 1252 and into the annular space between the inner transition piece 1261 and the outer transition piece 1262. The compressed air introduced into the annular space can cool the inner liner 1251 and the inner transition piece 1261.
The high-temperature and high-pressure combustion gas produced by the combustor 1200 is supplied to the turbine 1300 through the liner 1250 and the transition piece 1260. As the insulation expansion of the combustion gas is made in the turbine 1300, the combustion gas collides with a plurality of blades radially disposed on the rotary shaft of the turbine 1300 so that the thermal energy of the combustion gas is converted into mechanical energy that rotates the rotary shaft. A part of the mechanical energy obtained from the turbine 1300 is supplied as energy necessary for compressing the air in the compressor 1100, and the remaining energy is used as available energy to drive a generator to produce power.
Meanwhile, recently, a fuel nozzle that lowers the ratio of natural gas and increases the ratio of hydrogen has been studied. A gas turbine that uses fuel with an increased hydrogen rate is referred to as a ‘hydrogen turbine’. As a fuel nozzle used in the hydrogen turbine, a micro-mixer as shown in
Referring to
The nozzle cylinder 2100 formed to extend in one direction may supply fuel. The nozzle cylinder 2100 can be formed in a cylindrical shape, but is not limited thereto. The fuel (F) can be hydrogen, natural gas, or a mixed combustion in which hydrogen and natural gas are mixed.
A space through which the fuel (F) flows is formed in the nozzle cylinder 2100, and a plurality of fuel holes 2110 through which the fuel flows are formed in a surface of the nozzle cylinder 2100. The plurality of fuel holes 2110 can be formed from a portion surrounded by the shroud 2300.
Referring to
The fuel can be supplied to a mixing flow path (S) formed between the nozzle cylinder 2100 and the shroud 2300 through the plurality of fuel holes 2110 while flowing in a longitudinal direction of the nozzle cylinder 2100.
A head end plate 1231 is coupled to a nozzle casing 1232 at an end of the nozzle casing 1232 constituting an outer wall of the fuel nozzle assembly 1230 to seal the nozzle casing 1232, and can be coupled to a manifold configured to supply fuel to the nozzle cylinder 2100 and associated valves. In addition, the head end plate 1231 supports the fuel nozzle 2000 arranged in the nozzle casing 1232. The fuel nozzle 2000 is fixed to the head end plate 1231 by the nozzle flange 2200 disposed at one end of the nozzle cylinder 2100.
The fuel (F) passes through the head end plate 1231 through a fuel injector to move in a longitudinal direction of the nozzle cylinder 2100 and flows into the mixing flow path (S) through the plurality of fuel holes 2110, is mixed with a compressed air (A), and is injected into the combustion chamber 1240.
The shroud 2300 is spaced apart from the nozzle cylinder 2100 and formed to surround the nozzle cylinder 2100 in the longitudinal direction to form the mixing flow path (S) in which fuel and air can be mixed while flowing. The shroud 2300 can be formed to extend in an extending direction of the nozzle cylinder 2100, and can be formed to be spaced apart from the nozzle cylinder 2100 by a predetermined distance to surround the nozzle cylinder 2100. The cylindrical shroud 2300 is illustrated in the exemplary embodiment. In this case, a cross section of the mixing flow path (S) formed by the nozzle cylinder 2100 and the shroud 2300 can be formed in an annular shape.
The fuel nozzle 2000 according to the exemplary embodiment has a simple structure and can be applied to a hydrogen turbine using hydrogen as a main raw material, thereby significantly reducing manufacturing cost.
Referring to
In each of the fuel nozzles 2001, 2002, and 2003, the positions of the fuel holes 2111, 2112, and 2113 are formed differently, and the number of high-frequency vibrations in each of the fuel nozzles 2001, 2002, and 2003 generated by the fuel containing hydrogen can be different. Therefore, it is possible to solve the problem of combustion instability caused by high-frequency resonance generated by the fuel containing hydrogen.
Referring to
That is, as the fuel hole 2110 is formed, a large amount of fuel (F) and compressed air (A) can be mixed in an upstream of the mixing flow path (S), and a small amount thereof can be mixed in a downstream of the mixing flow path (S), thereby improving mixing efficiency. In other words, when the same amount of fuel is supplied, a large amount of fuel (F) and compressed air (A) can be mixed in the upstream of the mixing flow path (S) and then continue to be mixed while flowing to the downstream of the mixing flow path (S), thereby improving mixing efficiency.
In addition, each of the plurality of fuel holes 2110 is formed to have the same size, but the intervals between the fuel holes 2110 are formed differently, and as shown in
Referring to
That is, as the fuel hole 2110 is formed, a large amount of fuel (F) and compressed air (A) can be mixed in the upstream of the mixing flow path (S), and a small amount thereof can be mixed in the downstream of the mixing flow path (S), thereby improving mixing efficiency. In other words, when the same amount of fuel is supplied, a large amount of fuel (F) and compressed air (A) is mixed in the upstream of the mixing flow path (S), and then continue to be mixed while flowing to the downstream of the mixing flow path (S), thereby improving mixing efficiency.
In addition, each of the plurality of fuel holes 2110 can be formed to have different size, but the intervals between the fuel holes 2110 are equally formed, and as shown in
Alternatively, the plurality of fuel holes 2110 can be formed to have different size, and the distance between the fuel holes 2110 can be formed differently. In this case, as shown in
Referring to
That is, at least one fuel nozzle among the plurality of fuel nozzles has different widths (L1 to L6) of the mixing flow path (S) between the nozzle cylinder 2100 and the shroud 2300, so that the number of high-frequency vibrations in each of the fuel nozzles 2001, 2002, and 2003 generated by the fuel containing hydrogen can be different. Therefore, it is possible to solve the problem of combustion instability caused by high-frequency resonance generated by the fuel containing hydrogen.
Referring to
Referring to
Referring to
It is understood that the shapes of the nozzle cylinder 2100 and the shroud 2300 are not limited to those shown in
As shown in
While one or more exemplary embodiments have been described with reference to the accompanying drawings, it will be apparent to those skilled in the art that various modifications and variations can be made through addition, change, deletion, or substitution of components without departing from the spirit and scope of the disclosure described in the appended claims, and these modifications and changes fall within the spirit and scope of the disclosure as defined in the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2021-0001525 | Jan 2021 | KR | national |
