Gas turbine combustor with multiple fuel stages and method of operation

Abstract

A combustor for a gas turbine engine, the combustor comprising: a head end section defining a head end plenum and comprising a fuel nozzle assembly; and a liner extending downstream from the head end section to the aft frame and defining a combustion chamber therein. A first injector disposed at a first axial location directs a first fuel / air mixture through the liner. A second injector disposed at a different second axial location directs a second fuel / air mixture through the liner. Each of the head end section, the first injector, and the second injector receives a respective air supply from a compressor exhaust plenum that at least partially surrounds the combustor. The respective air supply is directed to only one of the fuel nozzle assembly, the first injector, and the second injector. The first injector and the second injector receive more than 50% of the air supply from the compressor exhaust plenum.

Description

Technical Field

[0001] This disclosure relates generally to gas turbine combustors, and more specifically to combustors having multiple axial fuel injection stages and methods of operating such combustors. Background Technology

[0002] Gas turbine engines (such as those used for power generation) generally include: a compressor section; a combustion section having one or more burners; and a turbine section. The compressor section progressively increases the pressure of the working fluid to supply compressed working fluid to the combustion section. The compressed working fluid is directed through one or more fuel nozzles that extend axially within the front or head end of the burner. Fuel combines with the flow of the compressed working fluid to form a flammable mixture. This flammable mixture is burned in the combustion chamber to produce combustion gases with high temperature, high pressure, and high velocity. The combustion chamber is defined by one or more bushings or conduits that define a hot gas path through which the combustion gases are delivered to the turbine section. In annular combustion systems, multiple burners (each with its own fuel nozzle and bushing) produce combustion gases that drive the turbine section.

[0003] The combustion gases expand to do work as they flow through the turbine section. For example, the expansion of the combustion gases in the turbine section can cause a shaft connected to a generator to rotate to generate electricity. The turbine can also use a common shaft or rotor to drive a compressor or another mechanical load (e.g., a generator or propulsion unit).

[0004] In recent years, manufacturers of large gas turbine engines have devoted considerable effort to developing combustion systems that produce low emissions (e.g., NOx emissions). These systems often utilize fuel nozzles commonly referred to as “micromixers,” “advanced premixers,” or “bundle-tube fuel nozzles.” Each such fuel nozzle, located at the head end of the combustor, comprises a set of premixing tubes arranged within a housing and extending through a common fuel pressurization chamber defined by that housing. Each premixing tube has one or more fuel injection orifices that are in fluid communication with the fuel pressurization chamber. Air enters from the upstream end of the tube and mixes with fuel from the fuel injection orifices within the tube, causing the fuel / air mixture to exit through the outlet end of the tube and enter the combustion chamber. The flame produced by bundle-tube fuel nozzles is characteristically shorter.

[0005] Designing robust bundled-tube fuel nozzles with dozens of premixing tubes presents challenges. Some designs involve multiple components made of different materials, increasing product cost and complexity. Various methods have been employed to secure the tubes and associated housing components within the bundled-tube fuel nozzle, connect the bundled-tube fuel nozzle to the fuel delivery conduit, ensure sufficient mixing time, adequately cool hot surfaces, and minimize kinetic effects. Consequently, for a single combustor with many (e.g., five or six) bundled-tube fuel nozzles, hundreds of brazed joints and multiple sealing locations are employed. For gas turbine engines with six to eighteen combustors, these numbers increase exponentially.

[0006] Additional efforts to reduce emissions and improve the load-cutting capabilities of gas turbine engines have led to the development of axial fuel staging (“AFS”) systems (sometimes called “distributed combustion systems”). These systems include injectors positioned downstream of the head end, which introduce a fuel / air mixture as a cross-flow into the combustion gases produced by the head end fuel nozzle. The area where the axial fuel staging injector delivers the fuel / air mixture is often referred to as the “secondary combustion zone,” which is downstream of the “primary combustion zone” supplied by the head end fuel nozzle. The ability to control multiple fuel delivery locations (e.g., head and downstream injectors) provides gas turbine operators with greater flexibility to deload (i.e., reduce) the power output of the gas turbine engine and to distribute heat release, thereby reducing kinetic effects.

[0007] In an H-stage combustion system with both bundled fuel nozzles and axial fuel stagers, the air flowing to the bundled fuel nozzles is primarily used to cool the combustion bushing. That is, air from the compressor exhaust housing is guided through impingement holes in a flow sleeve (which surrounds the bushing) and moves through an annulus between the bushing and the flow sleeve, thereby convectively cooling the bushing. Consequently, the air pressure between the compressor exhaust housing and the bundled fuel nozzles drops significantly. A portion of the air is also guided to the axial fuel stagers.

[0008] Applying the aforementioned technologies to smaller combustors and gas turbine engine frames (e.g., F-class engines) would represent an advancement in this technology. In particular, an F-class combustor capable of being retrofitted would offer improved hydrogen combustion capacity and significantly enhanced load shedding capacity; achieve the same pressure ratio (dP / P), better NOx / T3.90 capacity, and control of outlet temperature distribution; and be delivered at a reasonable cost. This combustor would represent a significant advancement in gas turbine combustion technology. Summary of the Invention

[0009] A combustor for a gas turbine engine includes: a head section defining a head boost chamber and including a fuel nozzle assembly; a bushing extending downstream from the head section to a rear frame and defining a combustion chamber; a first plurality of injectors disposed at a first axial position to guide a first fuel / air mixture through the bushing; and a second plurality of injectors disposed downstream of the first plurality of injectors at a second axial position to guide a second fuel / air mixture through the bushing; wherein each of the head section, the first plurality of injectors, and the second plurality of injectors receives a corresponding air supply from a compressor exhaust boost chamber defined by a compressor exhaust housing that at least partially surrounds the combustor, and the corresponding air supply is directed to only one of the fuel nozzle assembly, the first plurality of injectors, and the second plurality of injectors; and wherein the first plurality of injectors and the second plurality of injectors receive more than 50% of the air supply from the compressor exhaust housing.

[0010] According to another aspect, a bundle-tube fuel nozzle assembly for a gas turbine combustor includes: a front plate facing a head-end air booster chamber; a rear plate facing a combustion chamber; a first plurality of premixing tubes extending from the front plate to the rear plate; an inner sidewall extending circumferentially around the plurality of premixing tubes and axially from the front plate to the rear plate; and an outer sidewall extending circumferentially around the inner sidewall and extending from the front plate to the rear plate; wherein the front plate, the rear plate, the inner sidewall, and the outer sidewall define an outer fuel booster chamber; wherein the front plate, the rear plate, and the inner sidewall define an inner fuel booster chamber in fluid communication with the outer fuel booster chamber, and each of the plurality of premixing tubes includes at least one fuel injection orifice passing through it, the at least one fuel injection orifice in fluid communication with the inner fuel booster chamber; and wherein the head-end air booster chamber is in fluid communication with the combustion chamber via an inlet end of the first plurality of premixing tubes.

[0011] On the other hand, a combustor for a gas turbine engine includes: a head section including a fuel nozzle assembly; a bushing extending downstream from the head section to a rear frame and defining a combustion chamber therein; a first plurality of injectors disposed at a first axial position spaced apart from the head section to guide a first fuel / air mixture through the bushing; and a second plurality of injectors disposed at a second axial position downstream of the first plurality of injectors to guide a second fuel / air mixture through the bushing; wherein the head section Each of the first plurality of injectors and the second plurality of injectors receives a corresponding air supply from a compressor exhaust booster chamber defined by a compressor exhaust housing that at least partially surrounds the burner. The corresponding air supply is directed to only one of the fuel nozzle assembly, the first plurality of injectors, and the second plurality of injectors. The second plurality of injectors receives a corresponding second air supply that is greater than each of a corresponding first air supply to the first plurality of injectors and a corresponding third air supply to the head section.

[0012] According to another aspect, a method of operating a gas turbine combustor having a plurality of axially spaced fuel stages includes: selectively directing a fuel and a first air supply through a fuel nozzle assembly in a head section of the gas turbine combustor to generate a first fuel / air mixture, and igniting it within a bushing defining a combustion chamber, the bushing extending downstream from the head section to a rear frame; selectively directing a second fuel / air mixture through the bushing from at least one of a first plurality of injectors located at a first axial position spaced from the head section; and selectively directing a third fuel / air mixture from at least one of a second plurality of injectors. The second plurality of injectors is positioned at a second axial position downstream of the first plurality of injectors, passing through the bushing; wherein each of the fuel nozzle assembly, the first plurality of injectors, and the second plurality of injectors receives a corresponding air supply from a compressor exhaust booster chamber defined by a compressor exhaust housing that at least partially surrounds the burner, and the corresponding air supply is directed to only one of the fuel nozzle assembly, the first plurality of injectors, and the second plurality of injectors; and wherein the second plurality of injectors receives a corresponding air supply that is greater than the respective air supply of each of the corresponding air supplies of the fuel nozzle assembly and the first plurality of injectors.

[0013] Another aspect of this disclosure includes a combustor head section with an integrated cooling system, the combustor head section comprising: a bundle-tube fuel nozzle assembly for a gas turbine combustor, the bundle-tube fuel nozzle assembly comprising: a front plate facing a head air pressurization chamber; a rear plate facing a combustion chamber; a first plurality of premixing tubes extending from the front plate to the rear plate; and a sidewall extending circumferentially around the first plurality of premixing tubes and axially from the front plate to the rear plate; wherein the front plate, the rear plate, and the sidewall define a fuel pressurization chamber, and each of the first plurality of premixing tubes includes at least one fuel injection orifice through which it is in fluid communication with the fuel pressurization chamber; and wherein the head air pressurization chamber is in fluid communication with the combustion chamber via an inlet end of the first plurality of premixing tubes; and wherein the integrated cooling system includes at least one airflow passage integral with the outer surface of a respective premixing tube and extending from the front plate to the rear plate.

[0014] Another aspect of this disclosure provides a combustor head section with an air supply system, the combustor head section including: a bundle-tube fuel nozzle assembly for a gas turbine combustor, the bundle-tube fuel nozzle assembly including: a front plate facing a head air pressurization chamber; a rear plate facing a combustion chamber; a first plurality of premixing tubes extending from the front plate to the rear plate; and a sidewall extending circumferentially around the first plurality of premixing tubes and axially from the front plate to the rear plate; wherein the front plate, the rear plate, and the sidewall define a fuel pressurization chamber, and the first Each of the plurality of premixing tubes includes at least one fuel injection orifice passing through it, the at least one fuel injection orifice being in fluid communication with the fuel boosting chamber; and wherein the air supply system includes: the head-end air boosting chamber; a first inlet flow regulator that partially defines the head-end air boosting chamber; and a second inlet flow regulator, wherein the head-end air boosting chamber is in fluid communication with the combustion chamber via the first plurality of premixing tubes, the first inlet flow regulator surrounding the bundled fuel nozzle assembly, and the second inlet flow regulator surrounding the first inlet flow regulator.

[0015] According to another aspect of this disclosure, a combustor head section having an air supply system includes: a bundle-tube fuel nozzle assembly for a gas turbine combustor, the bundle-tube fuel nozzle assembly including: a front plate facing the head air pressurization chamber; a rear plate facing the combustion chamber; a first plurality of premixing tubes extending from the front plate to the rear plate; a sidewall extending circumferentially around the first plurality of premixing tubes and axially extending from the front plate to the rear plate; and an outer sidewall extending from the front plate to the rear plate and surrounding the sidewall; wherein the front plate, the rear plate, and the sidewall define the fuel pressurization chamber. And each of the first plurality of premixing tubes includes at least one fuel injection orifice passing through it, the at least one fuel injection orifice being in fluid communication with the fuel boosting chamber; wherein the air supply system includes: the head-end air boosting chamber; an annular air boosting chamber defined between the outer sidewall and the sidewall; and a circumferential opening array defined to pass through the front plate around the periphery of the bundle-tube fuel nozzle assembly; wherein the head-end air boosting chamber is in fluid communication with the annular air boosting chamber via the circumferential opening array and with the combustion chamber via the first plurality of premixing tubes.

[0016] According to another aspect, a combustor for a gas turbine engine includes: a head section including a fuel nozzle assembly and defining a head air booster chamber; a bushing extending downstream from the head section toward a rear frame and defining a combustion chamber therein; a first plurality of injectors disposed at first axial locations spaced apart from the head section to guide a first fuel / air mixture through the bushing; and a dynamic mitigation system including a plurality of cold-side resonators disposed entirely within the head air booster chamber, each of the plurality of cold-side resonators having a resonator body having a closed end and an open neck opposite the closed end extending from the resonator body, wherein the resonator body defines a corresponding volume and the open neck is in fluid communication with the head air booster chamber.

[0017] Two or more aspects described in this disclosure (including those described in this overview section) may be combined to form specific embodiments not specifically described herein. That is, all embodiments described herein may be combined with each other.

[0018] Details of one or more exemplary embodiments are set forth in the following drawings and detailed description. Other features, objects, and advantages will be apparent from the drawings, description, and claims. Attached Figure Description

[0019] The specification with reference to the accompanying drawings sets forth a full and practiceable disclosure of the products and methods of the present invention for those skilled in the art, including their best mode, wherein:

[0020] Figure 1 This is a schematic diagram of a gas turbine assembly with a combustion system as described in this article;

[0021] Figure 2 It is based on this disclosure Figure 1 A perspective view of a combustor with multiple axial fuel stages used in a gas turbine assembly;

[0022] Figure 3A and Figure 3B They are Figure 2 Detailed and schematic cross-sectional views of the burner;

[0023] Figure 4 This is a side perspective view of the burner head section according to various aspects of this disclosure;

[0024] Figure 5 This is a perspective view of the front side of the bundle-tube fuel nozzle assembly and associated damper according to various aspects of this disclosure;

[0025] Figure 6 Based on all aspects of this disclosure Figure 5 A perspective view of the rear side of the bundle-tube fuel nozzle assembly, including an enlarged view of the cooling features associated with the bundle-tube fuel nozzle assembly;

[0026] Figure 7 This is a partial cross-sectional view of the bundle-tube fuel nozzle assembly disclosed herein;

[0027] Figure 8 This is an internal plan view of a portion of the bundle-tube fuel nozzle assembly disclosed herein;

[0028] Figure 9 This is an enlarged sectional view of the head section of the burner according to this disclosure;

[0029] Figure 10 This is a perspective view of a bundle-tube fuel nozzle assembly and associated fuel conduit according to various aspects of this disclosure;

[0030] Figure 11 This is a schematic diagram of the rear of the bundle-tube fuel nozzle assembly disclosed herein;

[0031] Figure 12 This is an enlarged cross-sectional view of multiple premixing tubes of a bundle-tube fuel nozzle assembly according to various aspects of this disclosure;

[0032] Figure 13This is an enlarged cross-sectional view of multiple premixing tubes and cooling features of a bundle-tube fuel nozzle assembly according to various aspects of this disclosure.

[0033] Figure 14 This is a side perspective view of the rear of the burner of the present invention, showing the relative positions of the first plurality of fuel injectors and the second plurality of fuel injectors;

[0034] Figure 15 This is a schematic diagram depicting a fuel circuit associated with the burner of the present invention according to various aspects provided herein;

[0035] Figure 16 These are a series of images illustrating various operating modes of the burner of the present invention according to various aspects of this disclosure, from ignition to full load; and

[0036] Figure 17 These are a series of images illustrating various operating modes of the burner of the present invention, from full load to flameout, according to various aspects of this disclosure. Detailed Implementation

[0037] The following detailed description illustrates, by way of example and not limitation, a gas turbine combustor having multiple axially spaced fuel stages and a method of operating such a gas turbine combustor. This specification enables those skilled in the art to manufacture and use the combustion system. This specification provides several embodiments of combustor assemblies and their various components, and includes what is currently considered the best mode for manufacturing and using the combustion system of the present invention. Exemplary combustion systems are described herein as part of heavy-duty gas turbine assemblies for power generation. However, the combustion systems described herein are contemplated for general applications in a wide range of fields beyond power generation.

[0038] As used herein, the terms “first,” “second,” and “third” are used interchangeably to distinguish one component from another and are not intended to indicate the location or importance of individual components. The terms “upstream” and “downstream” refer to the relative direction of fluid flow within a fluid passage. For example, “upstream” refers to the direction from which fluid flows, and “downstream” refers to the direction towards which fluid flows. Without any further specificity, the terms “front” and “rear” refer to directions, where “front” refers to the front end or compressor end of a gas turbine engine, and “rear” refers to the rear end or turbine end of a gas turbine engine.

[0039] The term "radially" refers to a relative direction that is substantially perpendicular to the axial centerline of a particular component, and the term "axially" refers to a relative direction that is substantially parallel to the axial centerline of a particular component. As used herein, the term "radius" (or any variation thereof) refers to a dimension extending outward from the center of any suitable shape (e.g., a square, rectangle, triangle, etc.), and is not limited to a dimension extending outward from the center of a circular shape. Similarly, as used herein, the term "circumference" (or any variation thereof) refers to a dimension extending around the center of any suitable shape (e.g., a square, rectangle, triangle, etc.), and is not limited to a dimension extending around the center of a circular shape. If a first component resides closer to the axis (i.e., the axial centerline) than a second component, it may be stated herein as the first component being "radially inward" or "inner" of the second component. On the other hand, if a first component resides further away from the axis than a second component, it may be stated herein as the first component being "radially outward" or "outer" of the second component. As shown above, and depending on the context, such terms may be applied relative to the axis of a combustor or the axis of a gas turbine engine.

[0040] When an element or layer is referred to as “on another element or layer,” “joined to another element or layer,” “connected to another element or layer,” “coupled to another element or layer,” or “mounted to another element or layer,” it may be directly on, joined to, connected to, coupled to, or mounted to another element or layer, or an intermediary element or layer may be present. In contrast, when an element is referred to as “directly on another element or layer,” “directly joined to another element or layer,” “directly connected to another element or layer,” or “directly coupled to another element or layer,” no intermediary element or layer is present. Other terms used to describe the relationship between elements should be interpreted in a similar manner (e.g., “between” vs. “directly between,” “adjacent” vs. “directly adjacent,” etc.). As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. The verb forms “couple” and “mount” are used interchangeably herein.

[0041] Each example is provided by way of explanation, not limitation, of the invention. Indeed, it will be apparent to those skilled in the art that modifications and variations may be made to the combustion systems and components thereof without departing from the scope or spirit of this disclosure. For example, features illustrated or described as part of one embodiment may be used in another embodiment to produce yet another embodiment. Therefore, this disclosure is intended to cover such modifications and variations that fall within the scope of the appended claims and their equivalents. While exemplary embodiments of the combustion systems and methods of the present invention will be generally described for illustrative purposes in the context of heavy-duty, power-generating gas turbine engines, those skilled in the art will readily understand that embodiments of this disclosure can be applied to any combustor incorporated into a turbine, and are not limited to gas turbine combustors, unless expressly stated in the claims.

[0042] Reference will now be made specifically to various embodiments of the combustion system and method of the present invention, one or more examples of which are illustrated in the accompanying drawings. In the detailed description, numbers and letters are used to refer to features in the drawings. Similar or related names in the drawings and description have been used to refer to similar or related components.

[0043] Figure 1 A functional block diagram of an exemplary gas turbine engine 10 that can be incorporated into various embodiments of the present disclosure is provided. As shown, the gas turbine engine 10 generally includes an inlet section 12, which may include a series of filters, cooling coils, moisture separators and / or other devices to purify and otherwise regulate the working fluid (e.g., air) 14 entering the gas turbine engine 10. The working fluid 14 flows to a compressor section, wherein a compressor 16 gradually imparts kinetic energy to the working fluid 14 to produce compressed working fluid 18.

[0044] The compressed working fluid 18 is mixed with (gaseous or liquid) fuel 20 to form a flammable mixture within one or more burners 100 of the combustion section or system 24. This flammable mixture (whether gaseous or liquid fuel) is burned to produce combustion gases 26 with high temperature, high pressure, and high velocity. The combustion gases 26 flow through an expansion turbine 28 in the turbine section to perform work. For example, the expansion turbine 28 may be connected to a shaft 30 such that rotation of the expansion turbine 28 drives a compressor 16 to produce the compressed working fluid 18. Alternatively or otherwise, the shaft 30 may connect the expansion turbine 28 to a load (such as a generator 32) for generating electricity.

[0045] Exhaust gas 34 from the expansion turbine 28 flows through an exhaust section (not shown) that connects the expansion turbine 28 to an exhaust pipe downstream of the gas turbine engine 10. The exhaust section may include, for example, a heat recovery steam generator (not shown) for cleaning the exhaust gas 34 before it is released into the environment and for extracting additional heat from the exhaust gas.

[0046] In an F-class engine (e.g., a 9-frame F-class engine from GE Vernova in Greenville, South Carolina), the compressor exhaust housing partially defines a compressor exhaust boost chamber that surrounds a portion of each burner within the combustor (sometimes referred to as a "burner housing"). An expansion turbine housing or outer casing forms the final outer boundary of the boost chamber, and an inner housing defines the innermost boundary. Each burner is mounted through an opening in an array of circumferential openings in the compressor exhaust housing and positioned between struts supporting the compressor exhaust housing. For F-class engines, the openings in the compressor exhaust housing have a diameter of approximately 20 inches. The burner also engages at its rear end with hot gas path hardware (e.g., the first-stage hardware of the expansion turbine). Therefore, the main burner 100 is configured to be retrofitted into the existing environment of an F-class engine by virtue of its defined opening dimensions, strut locations, and expansion turbine hardware locations. A conventional Class F burner has a head section with swirling (swirling nozzle) fuel nozzles, a large head diameter, and a length-to-diameter ratio of approximately 3.4, where the length is measured from the head section to the rear frame.

[0047] Figure 2 yes Figure 1 A perspective view of the burner 100 in combustion section 24, schematically shown in the figure. Figure 3A , Figure 3B and Figure 4 This is a cross-sectional view of burner 100.

[0048] The burner 100 includes an end cap 102 to which a bundle-tube fuel nozzle assembly 200 is coupled. The end cap 102 defines the front boundary of a burner head section 104. The bundle-tube fuel nozzle assembly 200 defines the rear boundary of the burner head section 104 and the front boundary of the combustion chamber. The head section 104 further includes a flanged front housing 103 that extends circumferentially around an inner support cylinder 105 and extends axially between the end cap 102 and a burner mounting flange 107. The burner mounting flange 107 mounts the burner 100 to a compressor exhaust housing 17 that surrounds the entire portion of the burner 100 of the gas turbine engine 10 and defines a compressor exhaust boost chamber 19 that receives compressed working fluid (e.g., air) 18 from a compressor 16.

[0049] An internal or first inlet flow regulator (IFC) 109 extends between a mounting flange 107 and a bundled fuel nozzle assembly 200, which defines the downstream boundary of a head section 104 and separates the head section 104 from the primary combustion zone 120. An end cap 102, an inner support cylinder 105, and the internal inlet flow regulator 109 collectively define a head air boost chamber 111 that supplies air to the bundled fuel nozzle assembly 200. The bundled fuel nozzle assembly 200 has a diameter appropriately sized for retrofitting into existing F-Class engines (e.g., between 12 and 14 inches, or between approximately 30.5 and approximately 35.5 centimeters, compared to the 18- to 20-inch, or approximately 45.7 to approximately 50.8 centimeters, diameter of an H-Class engine). In other words, the bundled fuel nozzle assembly 200 spans the entire diameter of the front end of the bushing 106, whereas in a conventional combustion system, multiple fuel nozzles are mounted in a cover assembly that spans the diameter and defines the upstream boundary of the combustion chamber.

[0050] The inner inlet flow regulator 109 is surrounded by an outer inlet flow regulator or a second inlet flow regulator 113, providing an annular gap between the inner IFC 109 and the outer IFC 113. Both the inner IFC 109 and the outer IFC 113 are cylindrical ducts with multiple perforations to allow airflow from the compressor exhaust housing 17 surrounding the burner 100 into the head-end air booster chamber 111. The two sets of perforations (in terms of size, number, and alignment) in the outer inlet flow regulator 113 and the inner inlet flow regulator 109 are configured to achieve a desired pressure drop of the compressed air 18 entering the bundle-tube fuel nozzle assembly 200. In particular, the perforations in the outer IFC 113 are larger than those in the inner IFC 109, and the perforations in the outer IFC 113 are aligned with those in the inner IFC 109. This dimensional setting and alignment are important because the perforations in the inner inlet flow regulator 109 have been found to have the greatest impact on the pressure drop of the airflow.

[0051] Figure 4A perspective view of the internal components of the head section 104 of burner 100 is provided, which sequentially includes, from the front end, a plurality of fuel conduits 402 (specifically, fuel connection conduit 412), an end cap 102, an inner support cylinder 105, an inner support cylinder flange 121, an inner IFC mounting flange 115, an inner IFC 109, a bundle-tube fuel nozzle assembly 200, and an inner hula-hoop seal 219 surrounding the bundle-tube fuel nozzle assembly 200. In an exemplary embodiment, the inner IFC 109 is welded to the bundle-tube fuel nozzle assembly 200 at its rear end and to the inner IFC mounting flange 115 at its front end. The inner support cylinder flange 121 may be formed of two circumferential segments that together define an annular ring. The inner support cylinder 105 is formed of two circumferential halves that are bolted together or otherwise secured together to together define a complete cylindrical shape. The inner support cylinder 105 may include one or more windows 119 to facilitate engagement of the inner support cylinder 105 to the inner IFC 109. Two circumferential sections or halves of the inner support cylinder 105 are welded to the circumferential sections of the inner support cylinder flange 121, and sections of the inner support mounting flange 121 are bolted to the inner IFC mounting flange 115. The front ends of the inner support cylinder 105 (i.e., each circumferential half) are welded to the corresponding semi-circular panels of the end cap 102. The two semi-circumferential panels of the end cap 102 are bolted together or otherwise removably secured together to collectively define the front boundary of the head-end air booster chamber 111.

[0052] It should be noted that the above-described assembly of the internal components of the head section 104 is exemplary and should not be considered a limitation of the subject matter. The head section 104 (including its internal components discussed above) is configured to achieve various technical and practical objectives, such as providing airflow to the bundled fuel nozzle assembly 200 at a desired pressure, aiding in the assembly and maintenance of the head section 104, and meeting mechanical and aerodynamic requirements for operation and durability. Utilizing the described coupling of the components of the head section 104, the head section 104 (e.g., including the bundled fuel nozzle assembly 200 and the inner IFC 109) can be removed together from the bushing 106 of the burner 100. Additionally, an igniter, flame detector, kinetic pressure sensor, and / or other sensors may be disposed within or immediately adjacent to the head section 104 (e.g., slightly downstream of the bundled fuel nozzle 200).

[0053] like Figure 2 , Figure 3A and Figure 3BAs shown, the burner includes a bushing 106 and an outer sleeve 116. The bushing 106 defines a combustion chamber having a length “L” from a head section 104 (e.g., from the rear surface of the bundled fuel nozzle assembly 200) to a rear frame 112, wherein the length is approximately 2.7 times the head diameter. The bushing 106 has a generally cylindrical upstream portion 108 and a tapered downstream portion 110 extending between the upstream portion 108 and the rear frame 112. The upstream portion 108 and the downstream portion 110 of the bushing 106 may be continuous along the length of the burner 100, or may be formed as a first (e.g., upper or radially outward) flap member and a second (e.g., lower or radially inward) flap member joined by welding. Unlike many conventional F-series burners (which have separate cylindrical and conical portions coupled at a sealing joint), the bushing 106 of this invention can be considered a “monolithic” unit, in which the cylindrical portion 108 and the conical portion 110 are integral with each other. Therefore, eliminating the seal prevents airflow loss between portions 108 and 110.

[0054] Unlike the bushing 106, which extends axially between the head section 104 and the rear frame 112, the outer sleeve 116 includes a front (first) impact sleeve 122 and a rear (second) impact sleeve 124 spanning the length L of the burner 100. The front impact sleeve 122 circumferentially surrounds a first plurality of injectors 510 and extends axially from the head section 104 to the rear impact sleeve 124. The rear impact sleeve 124 circumferentially surrounds a second plurality of injectors 550 and extends axially from the front impact sleeve 122 to the rear frame 112. The front impact sleeve 122 includes a plurality of orifices configured (sized and shaped) to deliver airflow from the compressor exhaust booster chamber 19 at a predetermined first pressure drop for the first plurality of injectors.

[0055] The rear impact sleeve 124 includes a plurality of orifices configured (sized and shaped) to deliver airflow from the compressor exhaust boost chamber 19 at a predetermined second pressure drop for a second plurality of injectors, wherein a first pressure drop differs from the second pressure drop. In one embodiment, the first pressure drop is less than the second pressure drop. A first annulus is defined between the first impact sleeve 122 and the bushing 106, and a second annulus is defined between the second impact sleeve 124 and the bushing 106. The first and second annulus are fluidly isolated such that airflow through each impact sleeve 122, 124 is dedicated to the corresponding plurality of injectors. As described herein, airflow flows to the head section 104 (e.g., bundled fuel nozzle assembly 200), where the first plurality of injectors 510 and the second plurality of injectors 550 are discrete from each other.

[0056] To help guide air from the compressor exhaust booster chamber to the corresponding first or second annulus, the impact sleeves 122 and 124 may be provided with one or more aerodynamic guide vanes 126. Figure 2 One or more aerodynamic deflectors protrude from the outer surface of the respective impact sleeves 122, 124 into the high-speed airflow flowing through them. The aerodynamic deflector 126 acts as a flow trap, capturing and redirecting air that would otherwise have flowed through the impact orifices due to a lack of static pressure differential through a combination of stagnation and redirection, thus driving airflow through these orifices. The deflector 126 directs the airflow inward onto the hot surface of the bushing 106, thereby reducing the metal temperature to an acceptable level and enhancing the cooling capacity of the impact sleeves 122, 124. Furthermore, the deflector 126 helps ensure that sufficient airflow is directed to the respective plurality of AFS injectors 510, 550.

[0057] A guide vane 126 is mounted or formed on the surface of the respective impact sleeves 122, 124, along the side panels of the impact sleeves 122, 124 near the impact sleeve orifice. The guide vane 126 may at least partially surround one of the impact sleeve orifices and may include a first portion and an edge mounted or formed on the surface, the first portion defining an open side of the guide vane 126. This edge may be oriented in a plane substantially orthogonal to the surfaces of the impact sleeves 122, 124, or at some other angle toward the direction of airflow. When the impact sleeves 122, 124 are manufactured by additive manufacturing, the guide vane 126 may be integrally formed with the respective impact sleeves 122, 124. Alternatively, the guide vane 126 may be welded to the respective impact sleeves 122, 124. The number and position of the guide vanes 126 are determined by the shape of the impact sleeves 122, 124, the flow within the compressor exhaust housing 17, and the thermal load of the burner 100 on the bushing 106.

[0058] Each fuel injection system in the fuel injection system (bundle tube fuel nozzle assembly and axial fuel stager) will be discussed in detail below, starting with bundle tube fuel nozzle assembly 200 and referring to Figures 5 to 13 Although the head section 104 is illustrated as including the bundled fuel nozzle assembly 200 described herein, it should be understood that the head section 104 may include other types of fuel nozzle assemblies, such as those mounted in a cover plate that defines the front boundary of the combustion chamber. In other words, the rear plate 204 of the bundled fuel nozzle assembly 200 may be replaced by a conventional cover plate that itself benefits from the cooling system disclosed herein.

[0059] The bundled-tube fuel nozzle assembly 200 includes: a front plate 202 facing a head-end air booster chamber 111; a rear plate 204 facing a combustion chamber (e.g., primary combustion zone 120); a plurality of premixing tubes 210 extending from the front plate 202 to the rear plate 204; and a sidewall 206 extending circumferentially around the plurality of premixing tubes 210 and axially extending from the front plate 202 to the rear plate 204. The front plate 202, rear plate 204, and sidewall 206 collectively define a fuel booster chamber 220 (e.g., an internal fuel booster chamber) surrounding the plurality of premixing tubes 210. The head-end air booster chamber 111 is in fluid communication with the combustion chamber 120 via inlets of the premixing tubes 210. Each premixing tube 210 includes at least one fuel injection orifice 216 passing through it (in... Figure 13 As can be seen most clearly in the image, at least one fuel injection orifice is in fluid communication with the fuel pressurization chamber 220. The bundled fuel nozzle assembly 200 spans the entire diameter of the head section 104.

[0060] More specifically, each premixing tube 210 defines a premixing channel and extends from an inlet 212 defined in the front plate 202 through the fuel boosting chamber 220 to an outlet 214 defined in the rear plate 204. At least one fuel injection orifice 216 may be defined to pass through each of the plurality of premixing tubes 210 to provide fluid communication between the fuel boosting chamber 220 and the internal premixing channel. In operation, each premixing channel 210 may receive air at the inlet 212 and fuel at the fuel injection orifice 216, the air and fuel being mixed together and discharged at the outlet 214 as a fuel / air mixture for combustion in the primary combustion zone 120. It should be understood that the bundled tube fuel 200 may include any number of premixing tubes 210, and this disclosure should not be limited to any particular number of tubes 210 unless expressly stated in the claims.

[0061] The bundle-tube fuel nozzle assembly 200 has a sidewall 206 defining an inner sidewall, and a fuel pressurization chamber 220 is an inner fuel pressurization chamber. The inner sidewall (i.e., sidewall 206) is surrounded by an outer sidewall 226 having an axial length 208 suitable for facilitating additive manufacturing. As an example, the axial length 208 may be approximately 4 inches (approximately 10 cm). An outer fuel pressurization chamber 230 is defined between the inner sidewall 206 and the outer sidewall 226 (specifically, between the inner sidewall 206 and the pressurization chamber wall 224) and extends circumferentially around a first plurality of premixing tubes 210. At least one fuel conduit 402 ( Figure 4It is coupled to the front panel 202 and is in fluid communication with the external fuel booster chamber 230. It is noteworthy that the external fuel booster chamber 230 lacks a premixing pipe 210 (i.e., no premixing pipe 210 extends through or is in direct fluid communication with the external fuel booster chamber 230). For example... Figure 6 As shown, the periphery of the bundled fuel nozzle assembly 200 includes only cooling features (discussed below) and does not contain a premixing tube 210.

[0062] More specifically, such as Figure 7 As illustrated, multiple slotted fuel inlets 232 extend outward (i.e., upstream) from the front plate 202 to fluidly couple the external fuel pressurization chamber 230 to the corresponding fuel conduit 402. The slotted fuel inlets 232, integrally constructed with the bundled fuel nozzle assembly 200, are circumferentially spaced around the periphery of the bundled fuel nozzle assembly 200. Any number of slotted fuel inlets 232 can be used, with two slotted fuel inlets located at... Figure 7 The figure shows a partial cross-sectional view of an embodiment with three slotted fuel inlets 232. Thus, as shown, each of the plurality of circumferentially spaced coupling conduits 242 is in fluid communication with the external fuel pressurization chamber 230.

[0063] Fuel is supplied via fuel coupling conduit 242 ( Figure 3A , Figure 9 , Figure 10 The fuel coupling conduit is welded to a slotted fuel inlet 232 and flows into an annular external fuel pressurization chamber 230. In one embodiment, fuel flows through multiple sets of fuel delivery chutes 260 arranged in groups around the periphery of the bundled fuel nozzle assembly 200. Figure 8 The fuel enters the inner fuel pressurization chamber 220 from the outer fuel pressurization chamber 230. The spur 260 is tangentially arranged relative to the radius of the bundle-tube fuel nozzle assembly 200 and oriented to guide fuel between adjacent premixing tubes 210, as indicated by the arrows. This orientation facilitates fuel distribution from the periphery to the center of the bundle-tube fuel nozzle assembly 200. Because the air 18 flowing through the premixing tubes 210 is significantly hotter than the fuel, the fuel absorbs heat from the premixing tubes 210 as it traverses the inner fuel pressurization chamber 220. The fuel passes through one or more fuel injection holes 216 (… Figure 13 The mixture is mixed in the premixing tube 210 before being conveyed to the combustion chamber (e.g., primary combustion zone 120).

[0064] Figure 9An alternative view is provided of a sloping channel 260 arranged around the periphery of the bundle-tube fuel nozzle assembly 200. The opening 260 extends inward from the outer fuel pressurization chamber 230 relative to the radius of the bundle-tube fuel nozzle assembly 200 to fluidly connect the outer fuel pressurization chamber 230 to the inner fuel pressurization chamber 220. Because the air 18 flowing through the premixing tube 210 is significantly hotter than the fuel, the fuel absorbs heat from the premixing tube 210 as it traverses the inner fuel pressurization chamber 220. The fuel passes through one or more fuel injection orifices 216 and is mixed within the premixing tube 210 before being delivered to the combustion chamber (e.g., the primary combustion zone 120).

[0065] In an exemplary implementation, such as Figure 9 As shown, and as described in both co-pending U.S. Patent Application Serial Nos. 18 / 081,924 and 18 / 081,949, filed December 15, 2022, the booster chamber wall 224 defining the external fuel booster chamber 230 has a corrugated bellows shape, and the inner sidewall 206 extending axially between the front plate 202 and the rear plate 204 may include a self-fracture portion 264. The bellows-shaped booster chamber wall 224 intersects the inner sidewall 206 behind the self-fracture portion 264. The self-fracture portion 264 of the bellows-shaped booster chamber wall 224 and the inner sidewall 206 may surround the axial centerline C of the bundle-tube fuel nozzle assembly 200. L It extends in a ring shape to help manage thermal stress caused by the temperature difference between the fuel and compressed air.

[0066] The inner sidewall 206 and the outer sidewall 226 are radially spaced apart, such that the annular pressurization chamber 225 is defined therebetween, and more specifically, between the bellows-shaped pressurization chamber wall 224 and the outer sidewall 226. The annular pressurization chamber 225 is an air pressurization chamber, which is formed by multiple openings 223 ( Figure 7 The air supply is introduced through multiple openings defined around the periphery of the bundle-tube fuel nozzle assembly 200. Air is supplied from the head-end air pressurization chamber 111 through the air inlet opening 223. Figure 6 As shown, air from the annular booster chamber 225 is guided through the peripheral cooling passage 294 defined in the rear plate 204 and exits via the swirling funnel 298 into the combustion chamber, as discussed below.

[0067] Figure 10 The image illustrates a fuel delivery system 270 for a bundle-tube fuel nozzle assembly 200. In an exemplary embodiment, three fuel conduits 402 and a central fuel conduit 404 are illustrated. As discussed above, multiple (e.g., three) fuel coupling conduits 242 ( Figure 3AA slotted fuel inlet 232 is welded to the bundled fuel nozzle assembly 200. Each fuel coupling conduit 242 has a front end with a circular cross-section and a rear end with a slotted cross-section. The front end of each fuel coupling conduit 242 is welded to a straight pipe section 252 that extends between the fuel coupling conduit 242 and a fuel line bellows 262 (e.g., a single or dual fuel bellows assembly). The fuel line bellows 262 reduces the possibility of fuel leakage outside the head section 104 of the burner 100. The fuel line bellows 262 is attached to a mounting flange 272 for attaching a corresponding fuel conduit 402 to an end cap 102. A fuel connection conduit 412 extends in front of the end cap 102 for connection to a fuel supply line (not shown) outside the burner 100. As fuel conduit 402 extends from fuel conduit 242 through end cap 102, fuel conduit 402 is straight (without bends), and there are no fuel seals or fittings (e.g., compression fittings) within end cap 102 that could potentially deteriorate or fail and cause leakage. The absence of fuel seals and fittings is especially important when operating with highly reactive fuels (such as hydrogen).

[0068] like Figure 5 , Figure 7 , Figure 9 and Figure 10 As shown, the bundled fuel nozzle assembly 200 is provided with a central fuel inlet 234, which is integrally formed with the bundled fuel nozzle assembly 200 and extends axially outward from the front plate 202. A coupling conduit 244 is attached to the central fuel inlet 234, and a fuel conduit 254 engages with the coupling conduit 244. In this case, the coupling conduit 244 is straight, and the fuel conduit 254 may be provided with a bend. As illustrated, the central fuel inlet 234, the coupling conduit 244, and the fuel conduit 254 may each have a circular cross-section, but other cross-sectional shapes may be used alternatively. Like the fuel conduit 402, a fuel line bellows 262 is used to reduce the possibility of fuel leakage from the central fuel conduit 404. The central fuel conduit 404 also includes a mounting flange 272 for coupling to the end cap 102 and a fuel connection conduit 412 for coupling to an external fuel supply line (not shown).

[0069] The central fuel conduit 404 supplies fuel to the central fuel pressurization chamber 222, which in turn... Figure 11 The illustration is shown below. For simplicity, Figure 11This represents only a portion of the premixing pipe 210. The central fuel boosting chamber 222 is defined by a separator 280 comprising a plurality of boundary premixing pipes 282 and boundary airflow channels 284 disposed between each pair of adjacent boundary premixing pipes 282. The separator 280 extends axially from the front plate 202 to the rear plate 204, and the boundary airflow channels 284 are in fluid communication with the head-end air boosting chamber 111. Each of the plurality of boundary airflow channels 284 has a uniform cross-sectional shape from its inlet at the front plate 202 to its outlet defined in the rear plate 204. As will be discussed further below, the outlet is fluidly coupled to one or more cooling channels 294 defined in the rear plate 204.

[0070] Due to the separator 280, the premixing tube 210 defines a set of radially outer premixing tubes 210, 278, which are in fluid communication with the inner fuel pressurization chamber 220; a set of radially inner premixing tubes 210, 286, which are in fluid communication with the central fuel pressurization chamber 222; and the aforementioned boundary premixing tubes 210, 282, which are positioned along the separator 280 and form part of the separator 280. Figure 13 As shown in the optimal configuration, the boundary premixing tubes 210 and 282 have multiple fuel injection holes 216, at least one fuel injection hole 290 is in fluid communication with the internal fuel pressurization chamber 220, and at least one fuel injection hole 292 is in fluid communication with the central fuel pressurization chamber 222. The presence of the boundary premixing tube 282 between the internal fuel pressurization chamber 220 and the central fuel pressurization chamber 222 reduces thermal stress and ensures that even if the fuel pressurization chambers 220 and 222 are supplied individually or at different flow rates, there are no voids in the flame leading edge that would otherwise be caused by the solid boundary walls between the fuel pressurization chambers 220 and 222.

[0071] like Figure 12 and Figure 13As shown, at least one of the plurality of premixing tubes 210, 278, 286 includes at least one airflow passage 296 integral with the outer surface of the respective premixing tube 210, 278, 286 and extending from the front plate 202 of the bundled fuel nozzle assembly 200 to the rear plate 204. Each respective airflow passage 296 (which is part of the integrated cooling system of the head section 104) is in fluid communication with the head air boost chamber 211 and the combustion chamber (e.g., the primary combustion zone 120). More specifically, each of the respective airflow passages 296 has an inlet defined in the front plate 202 and an outlet defined in the rear plate 204, and the outlet is fluidly coupled to at least one cooling passage 294 defined in the rear plate 204 and extending between the respective outlets of adjacent premixing tubes 210, 278, 286 to provide convective cooling to the rear plate 204. To optimize the amount of cooling flow provided by cooling channel 294, a flow limiter (not shown) may be provided at the inlet. In various embodiments, the integrated cooling system includes one or two airflow channels 296 integral with the outer surface of the respective premixing tubes 210, 278, 286.

[0072] Each cooling channel in cooling channel 294 terminates in a swirl funnel 298, a conical structure in fluid communication with the combustion zone for conveying swirling air to the combustion zone. Specifically, each cooling channel in cooling channel 294 intersects the swirl funnel 298 tangentially, thereby promoting swirl as air exits from the swirl funnel 298. In some embodiments, the swirl funnel 298 may include a lip that reduces the diameter of the opening of the swirl funnel 298, which accelerates the outward flow from the swirl funnel 298. The introduction of small swirl streams between the non-swirling streams generated by premixing tubes 210, 278, 282, 286 promotes combustion within the primary combustion zone 120. The swirl funnel 298 is included in the integrated cooling system of the head section 104.

[0073] As described above, the bundle-tube fuel nozzle assembly 200 is formed from an additively manufactured body in which premixing tubes 210, 278, 282, and 286 are integrally connected to a front plate 202 and a rear plate 204. Each of the premixing tubes 210, 278, 282, and 286 has a wall thickness that is relatively thin compared to the thickness of the front plate 202. Other features, including an inner sidewall 206, an outer sidewall 226, a booster chamber wall 224 (e.g., a corrugated booster chamber wall), fuel inlets 232 and 234, a separator 280, and cooling features of the head-end section integrated cooling system (e.g., boundary airflow channels 284, airflow channels 296, convection cooling channels 294, and swirling funnels 298), are all incorporated into the additively manufactured body.

[0074] It has been found that thermal stress may occur in additively manufactured parts with components of varying thicknesses. To bridge the transition between the thickness of the front plate 202 and the wall thickness of the corresponding premixed tube 210, the front plate 202 includes a ridge 213. Figure 5 and Figure 7 The ridge protrudes radially outward from the front plate 202 in a honeycomb pattern between the premixing tubes 210 (e.g., between premixing tubes 278 in the first plurality of premixing tubes). The inlet ends of the premixing tubes 210, 278, 282, 286 are concentric with and recessed relative to the ridge 213, defining a recess. This configuration (i.e., the ridge, the recess, and the concentric arrangement) also helps to prevent the formation of steps in the inner surface of the premixing tubes 210, which could lead to flame dwell problems.

[0075] By additively manufacturing all components together into a single monolithic body, the need for multiple welded or brazed joints between the various small parts is eliminated, and the possibility of leakage from the fuel booster chambers 220, 222, and 230 is reduced. Furthermore, this type of assembly eliminates the need for seals between fuel nozzles in the head section, providing greater engineering flexibility related to premixing tube placement and avoiding additional hardware for completing the assembly.

[0076] Other features of the additively manufactured bundled tube fuel nozzle assembly are one or more quarter-wavelength tube dampers 300 (in... Figure 5 , Figure 9 and Figure 10 The installation body 302 (visible in the middle) Figure 7 The mounting body 302 is integrally coupled to the rear panel 204, extends through the fuel booster chambers 220, 222, and terminates at the upstream end of the front panel 202, wherein the term "upstream" is relative to the airflow through the premixing pipe 210 and / or the fluid through the combustion chamber. Figure 5 Most clearly visible is the extended damper body 306, which is welded to the damper mounting body 302 to create a quarter-wavelength tube damper of the desired length to mitigate dynamic effects at specific frequencies. The damper end 308 (of the extended damper body 306) has one or more orifices 310 to allow airflow through the damper 300. The damper end 308 is located distal to the front plate 202.

[0077] The damper mounting body 302 of each of the one or more quarter-wavelength tube dampers 300 is thermally decoupled from the inner sidewall 206 to prevent deformation that might otherwise be caused by the temperature difference between cold fuel and hot air flowing through the damper mounting body 302. Figure 7As shown, the damper mounting body 302 is surrounded by a bellows mounting body 304, which protrudes from the front plate 202 into the head-end air pressurization chamber 111. The bellows mounting body 304 extends a shorter distance from the front plate 202 compared to the damper mounting body 302. The annular gap between the damper mounting body 302 and the bellows mounting body 304 can be used for powder removal after additive manufacturing of the bundle-tube fuel nozzle assembly 200.

[0078] Bellows assembly 312 ( Figure 5 (As shown) A bellows mounting body 304 is coupled to each of one or more quarter-wavelength tube dampers 300 to prevent fuel leakage from fuel pressurization chambers 220, 222 into head-end pressurization chamber 111. A bellows assembly 312 includes a bellows with multiple swirls and a thin shield protecting the bellows. The bellows assembly 312 can be coupled to the bellows mounting body 304 by welding. The segmented construction of the quarter-wavelength tube dampers 300 (e.g., with the bellows assembly 312) allows for a significant reduction in stress caused by thermal growth in the quarter-wavelength tube dampers 300 distributed at different locations within the bundled-tube fuel nozzle assembly 200. This minimizes the likelihood of breakage at these locations and improves component life and durability.

[0079] like Figure 5 As shown, for example, one or more quarter-wavelength tube dampers 300 include a plurality of quarter-wavelength tube dampers, and the plurality of quarter-wavelength tube dampers 300 have at least two extended damper bodies 306 of different lengths to mitigate combustion dynamics effects at different frequencies. In the illustrated embodiment, seven quarter-wavelength tube dampers 300 are provided with four different lengths of damper bodies 306. More or fewer dampers 300 may be used as part of a combustion dynamics mitigation system for the burner 100. Alternatively, the damper bodies 306 may have a uniform length, and inserts of different lengths (not shown) may be installed therein to achieve desired damping characteristics.

[0080] It is further anticipated that the damper mounting body 302, bellows mounting body 304, and bellows assembly 312 can be used with one or more liquid fuel cartridges (not shown). In such cases, the liquid fuel cartridges will replace one or more of the extended damper bodies 306. For example, three extended damper bodies 306 (every other) surrounding the periphery of the bundled fuel nozzle assembly 200 can be replaced with liquid fuel cartridges, which may be designed with an injection pattern extending over approximately one-third of the rear plate 206 of the head section 104. Additionally or alternatively, the center damper mounting body 302 may be coupled to an ignition fuel nozzle that provides ignition fuel for starting highly reactive fuels such as hydrogen.

[0081] By using examples rather than limitations, and as Figure 3A and Figure 3B As shown, the dynamic mitigation system may further include a resonator 320 and / or a damper 340. The resonator 320 may be disposed within the head-end pressurization chamber 111 (i.e., as a "cold-side" damper), and the damper 340 may be disposed through the bushing 106 and the outer sleeve 122 and / or 124 (i.e., as a "hot-side" damper). Specifically, a plurality of resonators 320 may be disposed individually or in groups within the head-end pressurization chamber 111. Each resonator 320 has a resonator body with a defined volume. The resonator body is closed at one end and has an open neck extending from the resonator body opposite the closed end. This neck (having a smaller diameter than the closed end) is in fluid communication with the head-end air pressurization chamber 111. In an exemplary embodiment, the plurality of resonators 320 includes one or more groups of at least one resonator 320 (e.g., three groups of three resonators, each with a different volume). Each set of resonators is coupled to an upstream inner cylinder 105, which partially surrounds a fuel conduit 402, which is coupled to a bundled fuel nozzle assembly 200.

[0082] One or more (“hot-side”) dampers 340 may extend through corresponding outer sleeves 122, 124 and through bushing 106, such that the damper volume is in fluid communication with the combustion chamber. Such dampers 340 can be used to mitigate modal dynamic effects experienced during different operating conditions of the combustor 100. In an exemplary embodiment, a first damper 340 is disposed in front of a first plurality of injectors 510, a second damper 340 is disposed between the first plurality of injectors 510 and a second plurality of injectors 550, and a third damper 340 is disposed behind the second plurality of injectors 550. More or fewer dampers 340 may be used, and the dampers may be positioned at various locations in fluid communication with the combustion chamber. The first damper 340, second damper 340, and third damper 340 may have two or more different damper volumes to suppress different combustion dynamic frequencies. Therefore, the number and arrangement of the illustrated dampers 340 should not be considered as a limitation of the subject matter.

[0083] The dimensions of the burner 100, its head section 104, and its axial fuel staging system 500 are configured to be adapted to fit into existing openings in the exhaust housing 17 of a conventional 9F-class compressor. The head section 104, featuring a bundled fuel nozzle assembly 200, has been discussed above. (As...) Figure 2 , Figure 3A and Figure 3B As shown, the axial fuel staging system 500 includes: a first plurality of injectors 510 disposed at a first axial position to guide a first fuel / air mixture through a bushing 106 to a secondary combustion zone 512; and a second plurality of injectors 550 disposed at a second axial position downstream of the first plurality of injectors to guide a second fuel / air mixture through the bushing 106 to a tertiary combustion zone 514. Each of the head section 104 (e.g., a bundled fuel nozzle assembly 200), the first plurality of injectors 510, and the second plurality of injectors 550 receives a corresponding discrete air supply from a compressor exhaust booster chamber 19 defined by a compressor exhaust housing 17 that at least partially surrounds the combustor 100. A corresponding air supply is directed to only one of the head section 104 (e.g., the bundled fuel nozzle assembly 200), the first plurality of injectors 510, and the second plurality of injectors 550.

[0084] The first plurality of injectors 510 and the second plurality of injectors 550 together receive more than 50% of the air supply from the compressor exhaust housing 17. The first air supply to the first plurality of injectors 510 is volumetrically different from the second air supply to the second plurality of injectors 550 and the third air supply to the head section 104. The second plurality of injectors 550 receives a corresponding (second) air supply that is larger than the corresponding (third) air supply to the head section 104 (e.g., the bundled fuel nozzle assembly 200) and larger than the corresponding (first) air supply to the first plurality of injectors 510. Furthermore, in various preferred embodiments, the second air supply to the second plurality of injectors 550 is less than the sum of the first air supply to the first plurality of injectors 510 and the third air supply to the head section 104.

[0085] The axial fuel grading system 500 includes a first plurality of injectors 510 and a second plurality of injectors 550. The first plurality of injectors 510 are disposed on the front (upstream) portion of the bushing 106, and the second plurality of injectors 550 are disposed on the rear (downstream) portion of the bushing 106, which extends between the upstream portion and the rear frame 112. More specifically, as Figure 3A As shown, the upstream portion of bushing 106 is defined behind the bundle-tube fuel nozzle assembly 200 (or cover plate, if a different fuel nozzle is used) and between the first plurality of injectors 510 (i.e., immediately downstream of the first plurality of injectors 510), while the downstream portion of bushing 106 is defined between the upstream portion and the rear frame 112. In an exemplary embodiment, the first plurality of injectors 510 includes at least two injectors, and the second plurality of injectors 550 includes more than two injectors. In an illustrated embodiment, the first plurality of injectors 510 includes three injectors, and the second plurality of injectors 550 includes six injectors. In one exemplary embodiment, injectors 510, 550 are identical to each other. In other embodiments, different injectors may be used between the first injection stage and the second injection stage or within each injection stage.

[0086] In one implementation scheme, such as Figure 14 As shown, one of the first plurality of injectors 510 is disposed on the lower front section (e.g., half) 106A of the bushing 106, and two of the first plurality of injectors 510 are disposed on the upper front section (e.g., half) 106B of the bushing 106, wherein the lower front section 106A of the bushing 106 is located in the gas turbine engine 10 ( Figure 1 ) axial centerline GT C L Proximal to the side, and the upper front section 106B of bushing 106 in the gas turbine engine 10 ( Figure 1 ) axial centerline GT C LDistal side. In the illustrated embodiment, four of the second plurality of injectors 550 are disposed on the upper rear section (e.g., half) 106C of the bushing 106, and two of the second plurality of injectors 550 are disposed on the lower rear section (e.g., half) 106D of the bushing 106, wherein the upper rear section 106C of the bushing 106 is located in the gas turbine engine 10 ( Figure 1 ) axial centerline GT C L On the far side, and the rear lower section 106D of bushing 106 in gas turbine engine 10 ( Figure 1 ) axial centerline GT C L The proximal side. In other words, the injectors 510 and 550 on the upper sections of bushings 106A and 106B are located on the radially outer section of bushing 106, while the injectors 510 and 550 on the lower sections of bushings 106A and 106B are located on the radially inner section of bushing 106.

[0087] Injectors 510 may be fueled together via an “AFS-1” circuit. Alternatively, a first subset of injectors 510 may be coupled to a first fuel circuit (e.g., “AFS-1A”), and the remainder of injectors 510 (a second subset) may be coupled to a second fuel circuit (e.g., “AFS-1B”). Each of the first and second subsets of injectors 510 may include one or more injectors.

[0088] Similarly, injector 550 may be fueled via the “AFS-2” fuel circuit. Alternatively, a third subset of injectors 550 may be coupled to a third fuel circuit (“AFS-2A”), and the remainder of injectors 550 (a fourth subset) may be coupled to a fourth fuel circuit (“AFS-2B”). Each of the third and fourth subsets of injectors 550 may include one or more injectors.

[0089] exist Figure 14 In one illustrated non-limiting embodiment, the injector 510 on the lower front section 106A of bushing 106 is considered an "AFS-1A" circuit, and the injector 510 on the upper front section 106B of bushing 106 is considered an "AFS-1B" circuit. The injector 550 on the lower rear section 106C of bushing 106 is considered an "AFS-2A" circuit, and the injector 550 on the upper rear section 106D of bushing 106 is considered an "AFS-2B" circuit.

[0090] In operation, a first plurality of ejectors 510 and a second plurality of ejectors 550 receive more than 50% of the airflow from the compressor exhaust housing 17. The first plurality of ejectors 510 are surrounded by a first impact sleeve 122 having a first plurality of impact openings. A first air supply from the compressor exhaust booster chamber 17 is in fluid communication with the first plurality of ejectors 510 via the first plurality of impact openings, such that the corresponding first air supply experiences a first pressure drop due to flow through the first plurality of impact openings. Similarly, the second plurality of ejectors 550 are surrounded by a second impact sleeve 124 having a second plurality of impact openings. A second air supply from the compressor exhaust booster chamber 17 is in fluid communication with the second plurality of ejectors 550 via the second plurality of impact openings, such that the second air supply experiences a second pressure drop due to flow through the second plurality of impact openings. The second pressure drop differs from the first pressure drop.

[0091] like Figure 2 , Figure 3A and Figure 3B As shown, each of the first plurality of injectors 510 and the second plurality of injectors 550 includes an injector body 515 and an injector fuel conduit 520. The injector body has an elongated shape (e.g., a geometric stadium shape) that is longer in the axial direction than in the transverse direction. The injector fuel conduit extends from the injector body 515 along the outer surface of the outer sleeve 116 and through the mounting flange 107. Each injector fuel conduit 520 includes a straight portion 522 adjacent to the mounting flange 107 and may include a bend 524 between the straight portion and the corresponding injector body 515. An arched conduit shield or cover 526 is removably mounted above the straight portion 522 by bolting to an outer inlet flow regulator 113, which is part of the head section 104 of the burner 100.

[0092] In various embodiments, at least one injector of the first plurality of injectors 510 is oriented at a first angle relative to the burner centerline, and at least one injector of the second plurality of injectors 550 is oriented at a second angle relative to the burner centerline, wherein the first angle and the second angle are different from each other. For example, the first angle may be about 10 degrees (±5 degrees), and the second angle may be about 30 degrees (±5 degrees). In some embodiments, at least two injectors of the first plurality of injectors 510 are oriented at one or more first angles relative to the burner centerline, which one or more first angles are different from one or more second angles of the at least two injectors of the second plurality of injectors 550. In some embodiments, at least two injectors of the second plurality of injectors 550 are oriented at different angles relative to the burner centerline. For example, the rear ends of adjacent injector pairs in the second plurality of injectors may be oriented toward each other, such as... Figure 3A and Figure 14As shown. One or more first angles of at least two injectors in the first plurality of injectors 510 and one or more second angles of at least two injectors in the second plurality of injectors 550 are configured to promote complete combustion and optimize outlet temperature distribution, emission distribution, or both.

[0093] Figure 15 This is a schematic diagram of the control for fuel delivery to burner 100 as described herein. Fuel from the fuel supply is guided through a series of gas control valves (GCV1-GCV4) and optional discrete valves 602, 604 associated with the fuel circuit for a given burner component or region. Control valves GCV1-GCV4 and discrete valves 602, 604 communicate electronically with controller 600, as shown by dashed lines.

[0094] More specifically, controller 600 controls GCV1 to regulate fuel flow to the central pressurization chamber 222 of the bundle-tube fuel nozzle assembly (“BTFN”) 200 (or, for example, to the central fuel nozzle of the head section 104). Controller 600 controls GCV2 to regulate fuel flow to the internal pressurization chamber 220 of the bundle-tube fuel nozzle assembly 200 (or, for example, to an external fuel nozzle positioned around the central nozzle of the head section 104). Controller 600 controls GCV3 to regulate fuel flow to a first plurality of injectors 510 located at a first axial distance from the head section 104. In an embodiment where the first plurality of injectors 510 includes a first subset and a second subset of injectors, the first subset of injectors may be fueled via an “AFS-1A” circuit, while the second subset of injectors may be fueled via an “AFS-1B” circuit. A discrete (on / off) valve 602 may be used to direct (or stop) flow to the “AFS-1B” circuit. Similarly, in an embodiment where the second plurality of injectors 550 includes a first subset and a second subset of injectors, the first subset of injectors can be fueled via an "AFS-2A" circuit, while the second subset of injectors can be fueled via an "AFS-2B" circuit. A discrete (on / off) valve 604 can be used to direct (or stop) flow to the "AFS-2B" circuit.

[0095] Figure 16 A diagram illustrating the gradual increase in gas turbine load from ignition to full speed and full load is provided. Figure 17 A diagram illustrating the unloading process of a gas turbine engine from full speed and full load to shutdown (combustion system shutdown) is provided. Figure 16 and Figure 17 In this context, the letter "H" represents "hot" to indicate the subset supplied with fuel, while the letter "C" represents "cold" to indicate the subset not supplied with fuel. Figure 16 and Figure 17The load percentage mentioned in the discussion is representative of the operating temperature of the gas turbine combustor 100. Therefore, such a load percentage should not be considered limiting.

[0096] As described herein, this disclosure provides a method of operating a gas turbine combustor 100 having a plurality of axially spaced fuel stages. The method includes: selectively directing a fuel and a first air supply through a fuel nozzle assembly (e.g., a bundle-tube fuel nozzle assembly 200) in a head section 104 of the gas turbine combustor 100 to generate a first fuel / air mixture; and igniting the mixture within a bushing 106 to generate combustion gases, the bushing defining a combustion chamber, the bushing 106 extending downstream from the head section 104 to a rear frame 112. The method further includes: selectively directing a second fuel / air mixture from at least one of a first plurality of injectors 210 disposed at a first axial position spaced apart from the head section 104; and selectively directing a third fuel / air mixture from at least one of a second plurality of injectors 550 disposed at a second axial position downstream of the first plurality of injectors 510. Each of the bundled fuel nozzle assembly 220, the first plurality of injectors 510, and the second plurality of injectors 550 receives a corresponding discrete air supply from a compressor exhaust pressurization chamber 19, defined by a compressor exhaust housing 17, which at least partially surrounds the burner 100. The corresponding air supply is directed to only one of the bundled fuel nozzle assembly 220, the first plurality of injectors 510, and the second plurality of injectors 550. The second plurality of injectors 550 receives a corresponding air supply that is greater than the corresponding air supply of the bundled fuel nozzle assembly 220 and greater than the corresponding air supply of the first plurality of injectors 510.

[0097] The method steps of selectively directing fuel and initial air supply through the head section 104, including the bundle-tube fuel nozzle assembly 200, occur in all combustion modes present from ignition to full-speed, full-load operation, such as... Figure 16 The image in the text represents this.

[0098] As described herein, the bundled fuel nozzle assembly 200 defines a central fuel pressurization chamber 222 and an inner fuel pressurization chamber 220 surrounding the central fuel pressurization chamber 222. A method of selectively directing fuel and a first air supply through a head section 104 including the bundled fuel nozzle assembly 200 includes the steps of directing fuel through both the central fuel pressurization chamber 222 and the inner fuel pressurization chamber 220. In some embodiments, the central fuel pressurization chamber 222 and the inner fuel pressurization chamber 220 are supplied with fuel in a manner that creates a different fuel / air ratio between the central fuel pressurization chamber 222 and the inner fuel pressurization chamber 220.

[0099] As described above, the first plurality of injectors 510 includes one or more injectors in a first subset (e.g., AFS-1A) and the remaining number of injectors in a second subset (e.g., AFS-1B). Figure 16 As shown in Figure 2, the method steps of selectively guiding a second fuel / air mixture from at least one of the first plurality of injectors 510 through bushing 106 from about 93% of full speed up to about 7% load include: supplying fuel to a first subset (e.g., AFS-1A) of one or more of the first plurality of injectors 510, and not supplying fuel to a second subset (e.g., AFS-1B) of the remaining number of injectors in the first plurality of injectors 510.

[0100] In some implementation schemes, such as Figure 14 As shown, a first subset of the first plurality of injectors 510 (e.g., AFS-1A) includes one or more injectors located on the front lower section 106A of the bushing 106, and the remaining number of injectors in the second subset (e.g., AFS-1B) of the first plurality of injectors 510 includes one or more injectors located on the front upper section 106B of the bushing 106.

[0101] When the load is increased from approximately 8% to approximately 17%, such as Figure 16 As shown in Figure 3, the method steps for selectively guiding a second fuel / air mixture from at least one of the first plurality of injectors 510 through the bushing 106 include: supplying fuel to all injectors in one or more of the first plurality of injectors 510.

[0102] As described above, the second plurality of injectors 550 includes one or more injectors from the third subset (e.g., AFS-2A) and the remaining number of injectors from the fourth subset (e.g., AFS-2B). From ignition to approximately 18% load, as Figure 16As shown in Images 1 through 3, the method of selectively directing a third fuel / air mixture from at least one of the second plurality of injectors 550 through the bushing 106 includes the step of not supplying fuel to the second plurality of injectors 550. Thus, as shown in Image 3, the first plurality of injectors 510 are supplied with fuel (represented by the letter "H"), and the second plurality of injectors 550 are not supplied with fuel (represented by the letter "C").

[0103] like Figure 16 As shown in Figure 4, the method steps of selectively directing a third fuel / air mixture from at least one of the second plurality of injectors 550 through bushing 106 from about 18% load to about 35% load include: supplying fuel to a third subset (e.g., AFS-2A) of one or more injectors and not supplying fuel to a fourth subset (e.g., AFS-2B) of the remaining one or more injectors of the second plurality of injectors 550.

[0104] In some implementation schemes, such as Figure 14 As shown, a third subset of the second plurality of injectors 550 (e.g., AFS-2A) includes one or more injectors located on the rear lower section 106C of bushing 106, and the remaining number of injectors in the fourth subset of the second plurality of injectors 550 (e.g., AFS-2B) includes one or more injectors located on the rear upper section 106D of bushing 106.

[0105] From approximately 36% load to full load, such as Figure 16 As shown in Figure 5, the method of selectively guiding a second fuel / air mixture from at least one of the first plurality of injectors 510 through the bushing 106 includes: supplying fuel to each of the first plurality of injectors 510, and selectively guiding a third fuel / air mixture from at least one of the second plurality of injectors 550 through the bushing 106 includes: supplying fuel to each of the second plurality of injectors 550.

[0106] Turn now Figure 17 The method of operating burner 100 further includes: preferably reducing the pressure on the gas turbine burner in a manner that maintains emissions compliance. For example... Figure 17 As shown in Figure 1, all circuits of the burner 100 are supplied with fuel from 100% load to approximately 36% load. The fuel supply to the respective circuits can be reduced to relieve the load on the gas turbine until the gas turbine reaches approximately 36% load.

[0107] The method steps of initiating mode switching at approximately 35% load and selectively directing a third fuel / air mixture from at least one of the second plurality of injectors 550 through bushing 106 include: stopping fuel supply to a fourth subset (e.g., AFS-2B) of one or more injectors. As discussed above, the second plurality of injectors 550 includes: the third subset of one or more injectors and the remaining number of injectors in the fourth subset of the second plurality of injectors. Figure 17 As shown in Figure 2, the gas turbine combustor 100 can continue to unload from about 35% load to about 18% load while fuel is redistributed among the remaining active circuits (i.e., the circuits supplying the bundled fuel nozzle assembly, AFS-1A injector, AFS-1B injector, and AFS-2A injector).

[0108] As described, a third subset of the second plurality of injectors 550 (e.g., AFS-2A) includes one or more injectors located on the rear lower section 106C of bushing 106, and the remaining number of injectors in the fourth subset of the second plurality of injectors 550 (e.g., AFS-2B) includes one or more injectors located on the rear upper section 106D of bushing 106.

[0109] Another mode transition begins at approximately 17% load and involves the method step of selectively directing a third fuel / air mixture from at least one of the second plurality of injectors 550 through bushing 106, comprising: stopping fuel supply to each of the second plurality of injectors 550 by stopping fuel supply to a third subset (e.g., AFS-2A) of the second plurality of injectors 550, as... Figure 17 As shown in Figure 3. Figure 17 As shown in Figure 3, the gas turbine combustor 100 can continue to unload from about 17% load to about 8% load while fuel is redistributed among the remaining active circuits (i.e., the circuits supplying the bundled fuel nozzle assembly, the AFS-1A injector, and the AFS-1B injector).

[0110] As discussed above, the first plurality of injectors 510 may include: a first subset of one or more injectors (e.g., AFS-1A) and the remaining number of injectors in a second subset (e.g., AFS-1B) of the first plurality of injectors 510. In some embodiments, the first subset of the first plurality of injectors 510 (e.g., AFS-1A) includes one or more injectors located on the lower front section 106A of the bushing 106, and the remaining number of injectors in the second subset (e.g., AFS-1B) of the first plurality of injectors 510 includes one or more injectors located on the upper front section 106B of the bushing 106.

[0111] Another mode conversion begins at approximately 7% load, and the method steps of selectively directing a second fuel / air mixture from at least one of the first plurality of injectors 510 through bushing 106 include: stopping fuel supply to a second subset (e.g., AFS-1B) of one or more injectors. Figure 17 As shown in Figure 4, the gas turbine combustor 100 can continue to unload from about 7% load to about 93% speed while fuel is redistributed between the remaining effective circuits (i.e., the circuits supplying the bundled fuel nozzle assembly and the AFS-1A injector).

[0112] Another mode transition begins at approximately 92% speed, and the method steps of selectively guiding a second fuel / air mixture from at least one of the first plurality of injectors 510 through the bushing 106 include: stopping fuel supply to each of the first plurality of injectors 510. Thus, as shown in Figure 5, only the bundle-tube fuel nozzle assembly 200 remains fuel-supplying, and two subsets of each group of plurality of injectors 510, 550 are not fuel-supplying.

[0113] The method further includes shutting off the gas turbine combustor. When the gas turbine combustor is shut off, the method steps of selectively directing fuel and a first air supply through a bundled fuel nozzle assembly 200 in the head section 104 of the gas turbine combustor 100 to generate a first fuel / air mixture include: reducing the fuel supply to the bundled fuel nozzle assembly 200 until flameout occurs.

[0114] To facilitate the implementation of the methods described herein, the gas turbine combustor 100 further includes a controller 600. Figure 15 The controller is configured to selectively direct fuel to the bundled fuel nozzle assembly 200, the first plurality of injectors 510, and the second plurality of injectors 550.

[0115] Exemplary embodiments of combustion systems, their various components, and methods of operation have been described in detail above. The methods, systems, and components described herein are not limited to the specific embodiments described herein, but rather the components of the methods and systems can be used independently and separately from other components described herein. For example, as described herein, the methods and systems described herein may have other applications not limited to the practice of using turbine components. Conversely, the methods and systems described herein can be implemented and used in conjunction with a variety of other industries.

[0116] Although the claimed subject matter has been described according to various specific embodiments, those skilled in the art will recognize that the technology can be practiced with modifications within the spirit and scope of the claims.

[0117] Exemplary terms that may be used to describe the burner of the present invention and its bundle-tube fuel nozzle assembly are as follows. Any feature in any term may be combined in any practical manner to present further embodiments.

[0118] According to a first aspect, a combustor for a gas turbine engine includes: a head section defining a head boost chamber and including a fuel nozzle assembly; a bushing extending downstream from the head section to a rear frame and defining a combustion chamber therein; a first plurality of injectors disposed at a first axial position spaced apart from the head section to guide a first fuel / air mixture through the bushing; and a second plurality of injectors disposed at a second axial position different from the first plurality of injectors to guide a second fuel / air mixture through the bushing; wherein each of the head section, the first plurality of injectors, and the second plurality of injectors receives a corresponding air supply from a compressor exhaust boost chamber defined by a compressor exhaust housing that at least partially surrounds the combustor, and the corresponding air supply is directed to only one of the fuel nozzle assembly, the first plurality of injectors, and the second plurality of injectors; and wherein the first plurality of injectors and the second plurality of injectors receive more than 50% of the air supply from the compressor exhaust housing.

[0119] Another aspect of this disclosure includes any of the foregoing aspects, and wherein the first air supply to the first plurality of injectors is volumetrically different from both the second air supply to the second plurality of injectors and the third air supply to the head section.

[0120] Another aspect of this disclosure includes any of the foregoing aspects, wherein an upstream portion of the bushing is defined between a head section and a first plurality of injectors, and a downstream portion of the bushing is defined between the first plurality of injectors and a rear frame; and wherein the second plurality of injectors are disposed on the downstream portion of the bushing.

[0121] Another aspect of this disclosure includes any of the foregoing aspects, and wherein the second air supply to the second plurality of injectors is greater than each of the first air supply to the first plurality of injectors and the third air supply to the head section.

[0122] Another aspect of this disclosure includes any of the foregoing aspects, and wherein the second air supply to the second plurality of injectors is less than the sum of the first air supply to the first plurality of injectors and the third air supply to the head section.

[0123] Another aspect of this disclosure includes any of the foregoing aspects, and wherein the first plurality of injectors is surrounded by a first impact sleeve having a first plurality of impact openings; and wherein a first air supply from the compressor exhaust booster chamber is in fluid communication with the first plurality of injectors via the first plurality of impact openings, such that the respective first air supply experiences a first pressure drop due to flow through the first plurality of impact openings.

[0124] Another aspect of this disclosure includes any of the foregoing aspects, and wherein the second plurality of injectors is surrounded by a second impact sleeve having a second plurality of impact openings; and wherein a second air supply from the compressor exhaust booster chamber is in fluid communication with the second plurality of injectors via the second plurality of impact openings, such that the second air supply experiences a second pressure drop due to flow through the second plurality of impact openings, the second pressure drop being different from the first pressure drop.

[0125] Another aspect of this disclosure includes any of the foregoing aspects, and wherein the first plurality of injectors includes at least two injectors; and wherein the second plurality of injectors includes more than two injectors.

[0126] Another aspect of this disclosure includes any of the foregoing aspects, and wherein at least one of the first plurality of injectors is disposed on a radially outer section of the bushing, and at least one of the first plurality of injectors is disposed on a radially inner section of the bushing; wherein the radially outer section of the bushing is distal to the axial centerline of the gas turbine engine, and the radially inner section of the bushing is proximal to the axial centerline of the gas turbine engine.

[0127] Another aspect of this disclosure includes any of the foregoing aspects, and wherein at least one of the second plurality of injectors is disposed on a radially outer section of the bushing, and at least one of the second plurality of injectors is disposed on a radially inner section of the bushing; wherein the radially outer section of the bushing is distal to the axial centerline of the gas turbine engine, and the radially inner section of the bushing is proximal to the axial centerline of the gas turbine engine.

[0128] Another aspect of this disclosure includes any of the foregoing aspects, and wherein the first plurality of injectors are divided into a first subset and a second subset, the first subset being coupled to a first fuel circuit and the second subset being coupled to a second fuel circuit.

[0129] Another aspect of this disclosure includes any of the foregoing aspects, and wherein the second plurality of injectors is divided into a third subset and a fourth subset, the third subset being coupled to a third fuel circuit and the fourth subset being coupled to a fourth fuel circuit.

[0130] Another aspect of this disclosure includes any of the foregoing aspects, and wherein the fuel nozzle assembly is a bundle-tube fuel nozzle assembly comprising: a front plate facing a head-end air booster chamber; a rear plate facing the combustion chamber; a plurality of premixing tubes extending from the front plate to the rear plate; and a sidewall extending circumferentially around the plurality of premixing tubes and axially from the front plate to the rear plate, such that the front plate, the rear plate, and the sidewall define a fuel booster chamber; wherein the head-end air booster chamber is in fluid communication with the combustion chamber via the plurality of premixing tubes; wherein each of the plurality of premixing tubes includes at least one fuel injection orifice passing through it, the at least one fuel injection orifice being in fluid communication with the fuel booster chamber; and wherein the bundle-tube fuel nozzle assembly spans the entire diameter of the head-end section.

[0131] Another aspect of this disclosure includes any of the foregoing aspects, and at least one resonator is configured to pass through the fuel pressurization chamber of the bundled fuel nozzle assembly and extend into the head end pressurization chamber.

[0132] Another aspect of this disclosure includes any of the foregoing aspects, and at least one resonator is disposed entirely within the head section, separate from the bundle-tube nozzle assembly, the at least one resonator having a body and a neck extending therefrom, the neck being in fluid communication with a head air pressurization chamber partially defined by an inlet flow regulator surrounding the head section.

[0133] Another aspect of this disclosure includes any of the foregoing aspects, and includes the head section of the bundled fuel nozzle assembly and the inlet flow regulator surrounding the bundled fuel nozzle assembly being removable together from the bushing.

Claims

1. A combustor for a gas turbine engine, the combustor comprising: A head section, the head section defining a head pressurization chamber and including a fuel nozzle assembly; A bushing that extends downstream from the head section to the rear frame and defines a combustion chamber therein; A first plurality of injectors are disposed at a first axial position spaced apart from the head section to guide a first fuel / air mixture through the bushing; A second plurality of injectors, disposed at a second axial position different from the first plurality of injectors, to guide a second fuel / air mixture through the bushing; Each of the head section, the first plurality of injectors, and the second plurality of injectors receives a corresponding air supply from a compressor exhaust pressurization chamber defined by a compressor exhaust housing that at least partially surrounds the burner, and the corresponding air supply is directed to only one of the fuel nozzle assembly, the first plurality of injectors, and the second plurality of injectors. and The first plurality of injectors and the second plurality of injectors receive more than 50% of the air supply from the compressor exhaust housing.

2. The burner of claim 1, wherein the first air supply to the first plurality of injectors is volumetrically different from both the second air supply to the second plurality of injectors and the third air supply to the head section.

3. The burner of claim 1, wherein an upstream portion of the bushing is defined between the head section and the first plurality of injectors, and a downstream portion of the bushing is defined between the first plurality of injectors and the rear frame; and wherein the second plurality of injectors are disposed on the downstream portion of the bushing.

4. The burner of claim 3, wherein the second air supply to the second plurality of injectors is greater than each of the first air supply to the first plurality of injectors and the third air supply to the head section.

5. The burner of claim 3, wherein the second air supply to the second plurality of injectors is less than the sum of the first air supply to the first plurality of injectors and the third air supply to the head section.

6. The burner of claim 1, wherein the first plurality of injectors are surrounded by a first impact sleeve having a first plurality of impact openings; and wherein a first air supply from the compressor exhaust booster chamber is in fluid communication with the first plurality of injectors via the first plurality of impact openings, such that the respective first air supply experiences a first pressure drop due to flow through the first plurality of impact openings.

7. The burner of claim 6, wherein the second plurality of injectors is surrounded by a second impact sleeve having a second plurality of impact openings; and wherein a second air supply from the compressor exhaust booster chamber is in fluid communication with the second plurality of injectors via the second plurality of impact openings, such that the second air supply experiences a second pressure drop due to flow through the second plurality of impact openings, the second pressure drop being different from the first pressure drop.

8. The burner of claim 1, wherein the first plurality of injectors comprises at least two injectors; and wherein the second plurality of injectors comprises more than two injectors.

9. The burner of claim 8, wherein at least one of the first plurality of injectors is disposed on a radially outer section of the bushing, and at least one of the first plurality of injectors is disposed on a radially inner section of the bushing; wherein The outer radial section of the bushing is located far from the axial centerline of the gas turbine engine, and the inner radial section of the bushing is located near the axial centerline of the gas turbine engine.

10. The burner of claim 8, wherein at least one of the second plurality of injectors is disposed on a radially outer section of the bushing, and at least one of the second plurality of injectors is disposed on a radially inner section of the bushing; wherein The outer radial section of the bushing is located far from the axial centerline of the gas turbine engine, and the inner radial section of the bushing is located near the axial centerline of the gas turbine engine.

11. The burner of claim 8, wherein the first plurality of injectors are divided into a first subset and a second subset, the first subset being coupled to a first fuel circuit and the second subset being coupled to a second fuel circuit.

12. The burner of claim 8, wherein the second plurality of injectors are divided into a third subset and a fourth subset, the third subset being coupled to a third fuel circuit and the fourth subset being coupled to a fourth fuel circuit.

13. The burner of claim 1, wherein the fuel nozzle assembly is a bundle-tube fuel nozzle assembly, the bundle-tube fuel nozzle assembly comprising: Front panel, the front panel facing the head end air pressurization chamber; Rear panel, the rear panel facing the combustion chamber; Multiple premixing tubes extending from the front plate to the rear plate; The front end air pressure chamber is defined by a front end air pressure chamber and a sidewall extending circumferentially around the plurality of premixing tubes and axially from the front plate to the rear plate. The front plate, the rear plate, and the sidewall define a fuel pressure chamber. The front end air pressure chamber is in fluid communication with the combustion chamber via the plurality of premixing tubes. Each of the plurality of premixing tubes includes at least one fuel injection orifice passing through it, the at least one fuel injection orifice being in fluid communication with the fuel pressure chamber. The bundled tube fuel nozzle assembly spans the entire diameter of the front end section.

14. The burner of claim 13, wherein at least one resonator is configured to pass through the fuel pressurization chamber of the bundled fuel nozzle assembly and extend into the head end pressurization chamber.

15. The burner of claim 13, wherein at least one resonator is disposed entirely within the head section, separate from the bundle-tube nozzle assembly, the at least one resonator having a body and a neck extending therefrom, the neck being in fluid communication with a head air pressurization chamber, the head air pressurization chamber being partially defined by an inlet flow regulator surrounding the head section.

16. The burner of claim 13, wherein the head section of the bundled fuel nozzle assembly and the inlet flow regulator surrounding the bundled fuel nozzle assembly are removable together from the bushing.

Images