Combustion section for a turbine engine

Abstract

A combustion section for a turbine engine, the combustion section comprising a wall at least partially forming a combustion chamber and a fuel nozzle extending through a respective portion of the wall, the fuel nozzle having a fuel nozzle body defining a central channel and a fuel nozzle centerline, the central channel opening to the combustion chamber at a fuel nozzle outlet, a swirler provided along the fuel nozzle body and extending into the central channel, the swirler having a helical vane wrapped circumferentially about the fuel nozzle centerline.

Description

TECHNICAL FIELD

[0001] The present subject matter relates generally to a combustion section for a turbine engine.BACKGROUND

[0002] Turbine engines are driven by a flow of combustion gases passing through the engine to rotate a multitude of turbine blades, which, in turn, rotate a compressor to provide compressed air to the combustor for combustion. A combustor can be provided within the turbine engine and is fluidly coupled with a turbine into which the combusted gases flow.

[0003] Historically, hydrocarbon fuels are used in the combustor of a turbine engine. Generally, air and fuel are fed to a combustion chamber, the air and fuel are mixed, and then the fuel is burned in the presence of the air to produce hot gas. The hot gas is then fed to a turbine where it cools and expands to produce power. By-products of the fuel combustion typically include environmentally unwanted byproducts, such as nitrogen oxide and nitrogen dioxide (collectively called NOx), carbon monoxide (CO), unburned hydrocarbons (UHC) (e.g., methane and volatile organic compounds that contribute to the formation of atmospheric ozone), and other oxides, including oxides of sulfur (e.g., SO2 and SO3).

[0004] To reduce the environmentally unwanted byproducts, other fuels, such as hydrogen, are being explored. Hydrogen or hydrogen mixed with another element has a higher flame temperature than traditional hydrocarbon fuels. That is, hydrogen or a hydrogen mixed fuel typically has a wider flammable range and a faster burning velocity than traditional hydrocarbon-based fuels.BRIEF DESCRIPTION OF THE DRAWINGS

[0005] A full and enabling disclosure of the present disclosure, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:

[0006] FIG. 1 is a schematic cross-sectional view of a turbine engine having a compressor section, a combustion section, and a turbine section in accordance with various aspects described herein.

[0007] FIG. 2 is a schematic view of a combustor of the combustion section of FIG. 1 along line II-II in accordance with various aspects described herein.

[0008] FIG. 3 is a schematic cross-sectional view illustrating portions of the combustor of FIG. 2 along line III-III in accordance with various aspects described herein.

[0009] FIG. 4 is a schematic partially cutaway view illustrating portions of a fuel nozzle assembly suitable for use as a fuel nozzle of FIGS. 2-3 with a swirler including a set of helical vanes.

[0010] FIG. 5 is a schematic cross-sectional view illustrating a portion of the fuel nozzle assembly of FIG. 4 along line V-V.

[0011] FIG. 6 is a schematic cross-sectional view illustrating a portion of the fuel nozzle assembly of FIG. 4 along line VI-VI.

[0012] FIG. 7 is a schematic cross-sectional view illustrating a portion of another fuel nozzle assembly suitable for use as the fuel nozzle of FIGS. 2-3, the fuel nozzle assembly including a fuel channel and a fluid channel.

[0013] FIG. 8 is a forward view from aft illustrating a portion of another fuel nozzle assembly suitable for use as the fuel nozzle assembly of FIG. 203, the fuel nozzle assembly including a vane hub.

[0014] FIG. 9 is a schematic side view illustrating another fuel nozzle assembly suitable for use as the fuel nozzle assembly of FIGS. 2-3, the fuel nozzle assembly including a centerbody.

[0015] FIG. 10 is a schematic cross-sectional view illustrating a portion of the fuel nozzle assembly of FIG. 9 along line X-X.DETAILED DESCRIPTION

[0016] Aspects of the disclosure described herein are directed to a swirler located within a fuel nozzle of a combustion section of a turbine engine. The combustion section has a combustor and a fuel nozzle. The combustor has a combustion chamber. The fuel nozzle has a central channel opening to the combustion chamber. The fuel nozzle has a swirler located in the central channel. The swirler includes a set of helical vanes.

[0017] During operation, a compressed air and fuel are fed to the central channel of the fuel nozzle. The compressed air flows through a passage within the set of helical vanes and around outer surfaces of the set of helical vanes. The set of helical vanes is configured to generate bulk swirl and micro swirls within the compressed airflow. The creation of both bulk swirl and micro swirls within the compressed airflow increases the capability of a flow of fuel to be broken up into a consistent, advantageous radial and circumferential phi concentration profile before the mixture is provided to the combustion chamber and flame front. High levels of mixedness (e.g. greater than or equal to 90%), or temporal consistency in the fuel air mixture provided by the mixer is advantageous to reducing unwanted temperature spikes, improving NOx emissions and desired flame behavior.

[0018] The fuel nozzle is especially well adapted for the use of hydrogen-containing fuel (hereinafter, “H2 fuel”). Specifically, the fuel nozzle is especially well adapted to feed a flow of H2 fuel to the combustion chamber. The flow of H2 fuel can include a gaseous H2 fuel, a liquid H2 fuel, or a combination thereof. The flow of H2 fuel can further be mixed with other fuels or fluids such as, but not limited to, natural gas, coke oven gas, diesel, Jet-A, or the like.

[0019] H2 fuels, when compared to traditional fuels (e.g., carbon fuels, petroleum fuels, etc.), have a lower carbon emissions. However, H2 fuels burn hotter than and are relatively more unstable when compared to traditional fuels. For example, H2 fuels have a higher burn rate and velocity than traditional fuels. As such, an improper mixture of H2 fuel and compressed air can result in flashback occurring or a flame generated through auto-ignition of the H2 fuel spreading to unwanted regions of the turbine engine. The improper mixture of H2 fuel and compressed air, for example, creates pockets of H2 fuel that in some instances can ignite within the fuel nozzle (e.g., flashback). The fuel nozzle, as described herein, includes the fuel nozzle having the set of helical vanes is especially suited for combustion sections utilizing H2 fuel through generation of the bulk swirl and micro swirls.

[0020] For purposes of illustration, the present disclosure will be described with respect to a turbine engine. It will be understood, however, that aspects of the disclosure described herein are not so limited and that a combustion section as described herein can be implemented in engines, including but not limited to turbojet, turboprop, turboshaft, and turbofan engines. Aspects of the disclosure discussed herein may have general applicability within non-aircraft engines having a combustor, such as other mobile applications and non-mobile industrial, commercial, and residential applications.

[0021] With the combustors and fuel nozzle assemblies described herein, gaseous hydrogen fuel can be used without the need of diluents. In some embodiments, no diluent is added to the combustion chamber and the fuel is substantially completely diatomic hydrogen without diluent. As used herein, the term “substantially completely,” is used to describe the amount of a particular element or molecule (e.g., diatomic hydrogen), refers to at least 99% by mass of the described portion of the element or molecule, such as at least 97.5%, such as at least 95%, such as at least 92.5%, such as at least 90%, such as at least 85%, or such as at least 75% by mass of the described portion of the element or molecule. In some examples, the fuel is entirely (e.g., 100%) hydrogen by mass.

[0022] As used herein, the term “swirled” fluid flow or iterations thereof refers to an axisymmetric fluid flow having a circumferential rotation, or swirl, about a central axis. The amount of swirl that fluid flow has is quantified by a swirl number. The swirl number is defined as an integral of the tangential momentum to the axial momentum of the flow of fluid with respect to the central axis.

[0023] As used herein, the term “turbulent” fluid flow or iterations thereof refers to a non-laminar, chaotic and localized fluid flow. Turbulence, for example, can be in the form of a localized swirls, vortices or eddies. The turbulence of a turbulent fluid flow is quantified through use of turbulent kinetic energy and the Reynolds number of the fluid.

[0024] In relation to one another, the swirl of a fluid flow refers to a large-scale organized rotational movement of the fluid flow, while the turbulence of a fluid flow refers to a localized chaotic movement of the fluid flow. It will be appreciated that a fluid flow can include both swirl and turbulence.

[0025] The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any implementation described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other implementations. Additionally, unless specifically identified otherwise, all embodiments described herein should be considered exemplary.

[0026] As used herein, the terms “first”, “second”, “third”, etc. may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components.

[0027] The terms “forward” and “aft” refer to relative positions within a turbine engine or vehicle and refer to the normal operational attitude of the turbine engine or vehicle. For example, with regard to a turbine engine, forward refers to a position closer to an engine inlet and aft refers to a position closer to an engine exhaust.

[0028] As used herein, the term “upstream” refers to a direction that is opposite the fluid flow direction, and the term “downstream” refers to a direction that is in the same direction as the fluid flow. The term “fore” or “forward” means in front of something and “aft” or “rearward” means behind something. For example, when used in terms of fluid flow, fore / forward can mean upstream and aft / rearward can mean downstream.

[0029] The term “fluid” may be a gas or a liquid. The term “fluidly coupled” means that a fluid is capable of making the connection between the areas specified.

[0030] The term “nozzle” has been used in various ways in the context of turbine engines. In the instant application, “nozzle” refers to a component having a portion for fluid coupling to a fuel supply and having at least one portion for fluidly coupling with a combustor portion, a combustor liner, a combustion chamber, or combinations thereof.

[0031] Additionally, as used herein, the terms “radial” or “radially” refer to a direction away from a common center. For example, in the overall context of a turbine engine, radial refers to a direction along a ray extending between a center longitudinal axis of the engine and an outer engine circumference.

[0032] All directional references (e.g., radial, axial, proximal, distal, upper, lower, upward, downward, left, right, lateral, front, back, top, bottom, above, below, vertical, horizontal, clockwise, counterclockwise, upstream, downstream, forward, aft, etc.) are only used for identification purposes to aid the reader's understanding of the present disclosure, and do not create limitations, particularly as to the position, orientation, or use of aspects of the disclosure described herein. Connection references (e.g., attached, coupled, connected, and joined) are to be construed broadly and can include intermediate structural elements between a collection of elements and relative movement between elements unless otherwise indicated. As such, connection references do not necessarily infer that two elements are directly connected and in fixed relation to one another. The exemplary drawings are for purposes of illustration only, and the dimensions, positions, order, and relative sizes reflected in the drawings attached hereto can vary.

[0033] The singular forms “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise. Furthermore, as used herein, the term “set” or a “set” of elements can be any number of elements, including only one.

[0034] Uses of “and” and “or” are to be construed broadly. For example, and without limitation, uses of “and” do not necessarily require all elements or features listed, and uses of “or” are inclusive unless such a construction would be illogical.

[0035] Approximating language, as used herein throughout the specification and claims, is applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about”, “approximately”, “generally”, and “substantially”, are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value, or the precision of the methods or machines for constructing or manufacturing the components and systems. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value, or the precision of the methods or machines for constructing or manufacturing the components and systems. For example, the approximating language may refer to being within a 1, 2, 4, 5, 10, 15, or 20 percent margin in either individual values, range(s) of values and endpoints defining range(s) of values. Here and throughout the specification and claims, range limitations are combined and interchanged, such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise. For example, all ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other.

[0036] “Proximate” as used herein is a descriptor for locating parts described herein. Further, the term “proximate” means nearer or closer to the part recited than the following part. For example, a first aperture proximate a wall, the first aperture located upstream from a second aperture means that the first aperture is closer to the wall than the first aperture is to the second aperture.

[0037] Additionally, as used herein, a “controller” can include a component configured or adapted to provide instruction, control, operation, or any form of communication for operable components to effect the operation thereof. A controller can include any known processor, microcontroller, or logic device, including, but not limited to: field programmable gate arrays (FPGA), an application specific integrated circuit (ASIC), a full authority digital engine control (FADEC), a proportional controller (P), a proportional integral controller (PI), a proportional derivative controller (PD), a proportional integral derivative controller (PID controller), proportional resonant controller (PR), a hardware-accelerated logic controller (e.g. for encoding, decoding, transcoding, etc.), the like, or a combination thereof. Non-limiting examples of a controller can be configured or adapted to run, operate, or otherwise execute program code to effect operational or functional outcomes, including carrying out various methods, functionality, processing tasks, calculations, comparisons, sensing or measuring of values, or the like, to enable or achieve the technical operations or operations described herein. The operation or functional outcomes can be based on one or more inputs, stored data values, sensed or measured values, true or false indications, or the like. While “program code” is described, non-limiting examples of operable or executable instruction sets can include routines, programs, objects, components, data structures, algorithms, etc., that have the technical effect of performing particular tasks or implement particular abstract data types. In another non-limiting example, a controller can also include a data storage component accessible by the processor, including memory, whether transient, volatile or non-transient, or non-volatile memory.

[0038] Additional non-limiting examples of the memory can include Random Access Memory (RAM), Read-Only Memory (ROM), flash memory, or one or more different types of portable electronic memory, such as discs, DVDs, CD-ROMs, flash drives, universal serial bus (USB) drives, the like, or any suitable combination of these types of memory. In one example, the program code can be stored within the memory in a machine-readable format accessible by the processor. Additionally, the memory can store various data, data types, sensed or measured data values, inputs, generated or processed data, or the like, accessible by the processor in providing instruction, control, or operation to effect a functional or operable outcome, as described herein. In another non-limiting example, a controller can be configured for comparing a first value with a second value and operating and controlling operations of additional components based on the satisfying of that comparison. For example, when a sensed, measured, or provided value is compared with another value, including a stored or predetermined value, the satisfaction of that comparison can result in actions, functions, or operations controllable by the controller.

[0039] “Hydraulic diameter” as used herein is in reference to a characteristic diameter of portions of the fuel nozzle. Hydraulic diameter is a commonly used term when handling flow in non-circular tubes and channels. When the cross-section is uniform along the tube or channel length, it is defined asDH=4⁢ apwhere “a” is the cross-sectional area of the flow and “p” is the wetted perimeter of the cross-section. The hydraulic diameter can further be related to the Reynolds number of the fluid flow. As such, the hydraulic diameter can be used to at least partially quantify the flow of fluid through an area or pipe. It will be appreciated that the specific calculations for the hydraulic diameter are known and referenced herein without direct referenceFIG. 1 is a schematic view of a turbine engine 10. As a non-limiting example, the turbine engine 10 can be used within an aircraft. The turbine engine 10 can include, at least, a compressor section 12, a combustion section 14, and a turbine section 16 in a serial flow arrangement. A drive shaft 18 rotationally couples the compressor section 12 and turbine section 16, such that rotation of one affects the rotation of the other and defines an engine centerline or rotational axis 20 for the turbine engine 10. The turbine engine 10 includes an engine casing 29. The engine casing 29 houses at least a portion of the compressor section 12, the combustion section 14, and the turbine section 16.

[0041] The compressor section 12 can include a low-pressure (LP) compressor 22, and a high-pressure (HP) compressor 24 serially fluidly coupled to one another. The turbine section 16 can include an HP turbine 26, and an LP turbine 28 serially fluidly coupled to one another. The drive shaft 18 can operatively couple the LP compressor 22, the HP compressor 24, the HP turbine 26 and the LP turbine 28 together. Alternatively, the drive shaft 18 can include an LP drive shaft and an HP drive shaft. The LP drive shaft can couple the LP compressor 22 to the LP turbine 28, and the HP drive shaft can couple the HP compressor 24 to the HP turbine 26. An LP spool is defined as the combination of the LP compressor 22, the LP turbine 28, and the LP drive shaft such that the rotation of the LP turbine 28 can apply a driving force to the LP drive shaft, which in turn can rotate the LP compressor 22. An HP spool is defined as the combination of the HP compressor 24, the HP turbine 26, and the HP drive shaft such that the rotation of the HP turbine 26 can apply a driving force to the HP drive shaft which in turn can rotate the HP compressor 24.

[0042] The compressor section 12 includes a plurality of axially spaced stages (not illustrated). Each stage includes a set of circumferentially-spaced rotating blades and a set of circumferentially-spaced stationary vanes. The compressor blades for a stage of the compressor section 12 can be mounted to a disk, which is mounted to the drive shaft 18. Each set of blades for a given stage can have its own disk. The vanes of the compressor section 12 can be mounted to a shroud or casing, which can extend circumferentially about and enshroud one or more sections of the turbine engine 10. It will be appreciated that the representation of the compressor section 12 is merely schematic and that there can be any number of blades, vanes and stages. Further, it is contemplated that there can be any number of other components within the compressor section 12.

[0043] Similar to the compressor section 12, the turbine section 16 includes a plurality of axially spaced stages, with each stage having a set of circumferentially-spaced, rotating blades and a set of circumferentially-spaced, stationary vanes. The turbine blades for a stage of the turbine section 16 can be mounted to a disk which is mounted to the drive shaft 18. Each set of blades for a given stage can have its own disk. The vanes of the turbine section 16 can be mounted to the shroud or casing in a circumferential manner. It is noted that there can be any number of blades, vanes and turbine stages as the illustrated turbine section 16 is merely a schematic representation. Further, it is contemplated that there can be any number of other components within the turbine section 16.

[0044] The combustion section 14 is provided serially between the compressor section 12 and the turbine section 16. The combustion section 14 is fluidly coupled to at least a portion of the compressor section 12 and the turbine section 16 such that the combustion section 14 at least partially fluidly couples the compressor section 12 to the turbine section 16. As a non-limiting example, the combustion section 14 can be fluidly coupled to the HP compressor 24 at an upstream end of the combustion section 14 and to the HP turbine 26 at a downstream end of the combustion section 14. The combustion section 14 includes a combustor 30.

[0045] The turbine engine 10 includes a fuel source 34. The fuel source 34 is any suitable container or vessel adapted to store a volume of fuel. The fuel within the fuel source 34 can have various states. As a non-limiting example, the fuel within the fuel source 34 can be a solid, a liquid, or a gas. The fuel source 34 is provided exterior the engine casing 29. The fuel source 34 can be provided exterior the turbine engine 10. As a non-limiting example, the turbine engine 10 can be coupled to an aircraft having a wing. The wing can include the fuel source 34. The fuel source 34 is configured to feed a flow of the fuel to the combustion section 14, specifically the combustor 30. While only a single fuel source 34 is illustrated, it will be appreciated that the turbine engine 10 can include or otherwise be coupled to any number of one or more fuel sources having any number of one or more types of fuel.

[0046] During operation of the turbine engine 10, ambient or atmospheric air is drawn into the compressor section 12 via a fan section (not illustrated) upstream of the compressor section 12, where the air is compressed defining a pressurized air. At least a portion of the pressurized air then flows into the combustion section 14 where the pressurized air is mixed with fuel from the fuel source 34 and ignited, thereby generating combustion gases. Some work is extracted from these combustion gases by the turbine section 16, which in turn drives the compressor section 12 and the fan section through the drive shaft 18. The combustion gases are ultimately discharged from the turbine engine 10 via an exhaust section (not illustrated) downstream of the turbine section 16. The pressurized airflow and the combustion gases can together define a working airflow that flows through the compressor section 12, the combustion section 14, and the turbine section 16 of the turbine engine 10.

[0047] FIG. 2 depicts a cross-sectional view of the combustion section 14 along line II-II of FIG. 1. The combustor 30 can have a can, can-annular, or annular arrangement depending on the type of engine in which the combustor 30 is located. In a non-limiting example, the combustor 30 can have a combination arrangement located with the engine casing 29. The engine casing 29 can enshroud or cover at least a portion of the combustion section 14. The combustion section 14 includes a combustion section centerline 33. The combustion section 14 can be collinear with the engine centerline or rotational axis 20 such that the combustion section centerline 33 extends along the engine centerline or rotational axis 20. Alternatively, at least a portion of the combustion section centerline 33 can be offset from the engine centerline or rotational axis 20. The combustion section centerline 33 defines a radial direction Rd, an axial direction Ad, and a circumferential direction Cd.

[0048] The combustor 30 includes a combustor liner 40. The combustor liner 40 can include an outer liner 41 and an inner liner 42 concentric with respect to each other and arranged in an annular fashion about the engine centerline or rotational axis 20. The combustor liner 40 can have various configurations. As a non-limiting example, the combustor liner 40 can extend continuously about an entirety of a circumferential extent the combustion section centerline 33 in the circumferential direction Cd. As a non-limiting example, the combustor liner 40 can extend continuously about less than the entirety of the circumferential extent the combustion section centerline 33 in the circumferential direction Cd. As a non-limiting example, the combustor liner 40 can be segmented (e.g., formed of two or more bodies coupled to one another) in the circumferential direction Cd, the axial direction Ad, the radial direction Rd, or a combination thereof. As a non-limiting example, the combustor liner 40 can include two or more circumferential segments, with each segment of the two or more circumferential segments extending circumferentially about less than the entirety of the circumferential extent the combustion section centerline 33 in the circumferential direction Cd. The two or more circumferential segments, when coupled to each other, will collectively extend about the entirety of the circumferential extent the combustion section centerline 33 in the circumferential direction Cd.

[0049] The combustor 30 can include a dome wall 46 interconnecting opposing portions of the combustor liner 40. As a non-limiting example, the dome wall 46 can extend radially between the outer liner 41 and the inner liner 42. The dome wall 46 can be formed substantially perpendicular to the combustion section centerline 33. The dome wall 46, like the combustor liner 40, can extend continuously about an entirety of the circumferential extent of the combustion section centerline 33 in the circumferential direction Cd. Alternatively, the dome wall 46 can be segmented in the circumferential direction Cd, the radial direction Rd, or a combination thereof.

[0050] At least one of the dome wall 46 or the combustor liner 40 includes a set of fuel nozzle openings 72. As illustrated, the dome wall 46 includes the set of fuel nozzle openings 72. It will be appreciated, however, that at least one fuel nozzle opening of the set of fuel nozzle openings 72 can be located along a respective portion of the combustor liner 40.

[0051] It will be appreciated that in some configurations, the dome wall 46 can be excluded from the combustor 30. In such a configuration, the inner liner 42 and the outer liner 41 can meet at a common point. The dome wall 46 and the combustor liner 40 will be collectively referred to as a “wall” that defines the combustion chamber 50.

[0052] The combustor liner 40 and the dome wall 46 (if included) collectively form a combustion chamber 50. The combustion chamber 50 is arranged annularly about the combustion section centerline 33 in the circumferential direction Cd.

[0053] A compressed air passage 32 can be defined at least in part by both the combustor liner 40 and the engine casing 29. As a non-limiting example, the combustor liner 40 is spaced from the engine casing 29 to define the compressed air passage 32 therebetween. The compressed air passage 32 is fluidly coupled to the compressor section 12 (FIG. 1).

[0054] The combustion section 14 can include an annular arrangement of combustor portions 31 disposed around the engine centerline or rotational axis 20 of the turbine engine 10 in the circumferential direction Cd. It will be appreciated that one or more combustor portion of the annular arrangement of combustor portions 31 can be radially or axially offset in the radial direction Rd or axial direction Ad, respectively. The combustor portions 31 can, in some configurations, include or be configured as combustor cups, fuel cups, or nozzle cups.

[0055] Each combustor portion of the annular arrangement of combustor portions 31 includes a fuel nozzle assembly 48. For purposes of illustration, only a singular fuel nozzle assembly 48 is shown, however, it will be appreciated that each combustor portion of the annular arrangement of combustor portions 31 can include a respective fuel nozzle assembly 48. Each fuel nozzle assembly 48 that extends through a respective one fuel nozzle opening of the set of fuel nozzle openings 72.

[0056] The fuel nozzle assembly 48 is defined by a bluff area and a flow area. The bluff area is defined as a total surface area of the physical structure of the fuel nozzle assembly 48 and a wall through which the fuel nozzle assembly 48 extends (e.g., the dome wall 46, the inner liner 42, or the outer liner 41) confronting the combustion chamber 50. The flow area is defined as a volume of a fuel nozzle outlet 74 of a single fuel nozzle assembly 48. A ratio between the bluff area through which a respective fuel nozzle assembly 48 extends and the flow area of the respective fuel nozzle assembly 48 is greater than or equal to 0.01 and less than or equal to 10.

[0057] During operation, a fuel F is fed from the fuel source 34 and to the combustion chamber 50 through the annular array of combustor portions 31. Specifically, the fuel F is fed to the combustion chamber 50 through the fuel nozzle assembly 48 of at least one combustor portion of the annular array of combustor portions 31. The fuel F includes any suitable fuel, including gaseous fuel, such as H2 fuel. As a non-limiting example, the fuel F can include 100% H2 (e.g., without diluents). As another non-limiting example, the fuel F can include methane, such as in the form of natural gas. In some examples, the fuel F can be a combination of fuels using other fuels with H2 fuels. For example, the fuel F can comprise H2 fuel and methane. A controller 60 can be connected to and at least partially control operation of the fuel source 34, the fuel nozzle assembly 48, or both. The controller 60 can include a processor 62 and a memory 64.

[0058] FIG. 3 depicts a cross-section view of the fuel nozzle assembly 48 and a combustor portion 31 of the combustor 30 along line III-III in FIG. 2. The fuel nozzle assembly 48 is fluidly coupled with the fuel source 34, and an air source. The fuel source 34 is configured to hold a fuel F that is supplied to the combustor 30 during operation of the turbine engine 10 (FIG. 1). The air source is any suitable structure of the turbine engine 10 (FIG. 1) including a compressed air A such as, but not limited to, the compressor section 12. The compressed air A is fed to the compressed air passage 32. The fuel F and the compressed air A are each fed to the fuel nozzle assembly 48 and mixed to define a fuel air mixture M.

[0059] The fuel nozzle assembly 48 terminates at the fuel nozzle outlet 74. The fuel nozzle outlet 74 is fluidly coupled to the combustion chamber 50. The fuel nozzle outlet 74 is configured to exhaust the fuel air mixture M including fuel and air into the combustion chamber 50.

[0060] FIG. 4 is a schematic side view depicting a fuel nozzle assembly 100 suitable for use as the fuel nozzle assembly 48 of FIGS. 2-3. The fuel nozzle assembly 100 includes a fuel nozzle body 102. For purposes of illustration, the fuel nozzle body 102 is shown in phantom lines. The fuel nozzle assembly 100 includes a swirler 110 having a set of helical vanes 112.

[0061] The fuel nozzle body 102 is an annular shape and defines a fuel nozzle centerline 104. The fuel nozzle centerline 104 can be parallel with at least one of the engine centerline or rotational axis 20 (FIGS. 1-2), the combustion section centerline 33 (FIG. 2), or a combination thereof. Alternatively, the fuel nozzle centerline 104 can be non-parallel to the engine centerline or rotational axis 20 (FIG. 1), the combustion section centerline 33 (FIG. 2), or a combination thereof. A radially inner fuel nozzle body surface 106 with respect to the fuel nozzle centerline 104 defines a perimeter of a central channel 108. The central channel 108 is disposed upstream of the fuel nozzle outlet 74 and opens to the combustion chamber 50 (FIG. 3).

[0062] The fuel nozzle body 102 includes a fuel supply passage 117 extending therethrough. The fuel supply passage 117 is fluidly connected to a fuel source (e.g., the fuel source 34 of FIGS. 2-3). The fuel supply passage 117 terminates at an aperture 118 on the inner fuel nozzle body surface 106. One fuel supply passage 117 and one corresponding aperture 118 is illustrated in FIG. 4, but it is contemplated that the fuel nozzle body 102 can include any number of fuel supply passages 117 and corresponding apertures 118. The fuel supply passage 117 opens to the central channel 108 at the aperture 118. The aperture 118 can have various cross-sectional areas such as, but not limited to, a circle, an oval, a slot or rectangle, or any other polygonal shape.

[0063] Each helical vane of the set of helical vanes 112 extends between a first end 114 and a second end 116 axially opposing the first end 114 with respect to the fuel nozzle centerline 104. Each helical vane of the set of helical vanes 112 wraps circumferentially about at least a portion of the fuel nozzle centerline 104. The second end 116 of each helical vane of the set of helical vanes 112 is displaced greater than or equal to π / 4 radians and less than or equal to 10π radians from the first end 114 with the first end 114 coinciding to 0. Put another way, the second end 116 of each helical vane of the set of helical vanes 112 is circumferentially displaced greater than or equal to an eighth revolution from and less than or equal to 5 revolutions from the first end 114.

[0064] The set of helical vanes 112 includes any number of one or more helical vanes. As a non-limiting example, the set of helical vanes 112 includes a first helical vane 112a and a second helical vane 112b. The first helical vane 112a and the second helical vane 112b both wrap around the fuel nozzle centerline 104 collectively forming a double helix shape. The first helical vane 112a and the second helical vane 112b are radially separated from each other along the fuel nozzle centerline 104. That is, along the fuel nozzle centerline 104, the central channel 108 is unobstructed.

[0065] In the illustrated non-limiting example, the first end 114 of the first helical vane 112a is axially aligned with the first end 114 of the second helical vane 112b. Alternatively, the first end 114 of the first helical vane 112a can be axially unaligned with the first end 114 of the second helical vane 112b. In the illustrated non-limiting example, the second end 116 of the first helical vane 112a is axially aligned with the second end 116 of the second helical vane 112b. Alternatively, the second end 116 of the first helical vane 112a can be axially unaligned with the second end 116 of the second helical vane 112b.

[0066] Each helical vane of the set of helical vanes 112 includes an outer wall 122. The outer wall 122 defines an interior 124. A fuel channel 120 is formed within at least one interior 124 of the set of helical vanes 112. As a non-limiting example, the set of helical vanes 112 includes two helical vanes with each including a respective fuel channel 120 formed within their respective interior 124.

[0067] The swirler 110 includes a set of protrusions 126. Each protrusion of the set of protrusions 126 is a localized raised surface of the outer wall 122 extending from any suitable portion of the swirler 110. Optionally, some or all of the protrusions of the set of protrusions 126 can be hollow. In a non-limiting example, a first protrusion 126a of the set of protrusions 126 is located along the second end 116 of the first helical vane 112a protruding towards the combustion chamber 50 (FIG. 3) and another protrusion of the set of protrusions 126 is located along the second helical vane 112b protruding towards the combustion chamber 50 (FIG. 3). In another non-limiting example, two or more protrusions of the set of protrusions 126 can be located along a singular helical vane of the set of helical vanes 112. In yet another non-limiting example, a protrusion of the set of protrusions 126 is located on only a subset of the set of helical vanes 112. That is, not every helical vane of the set of helical vanes 112 needs to include a protrusion of the set of protrusions 126 thereon. While the set of protrusions 126 is illustrated as including two protrusions, the set of protrusions 126 can include any number of protrusions, including one.

[0068] The swirler 110 includes a fuel channel 120. The fuel channel 120 extends through a helical vane of the set of helical vanes 112. The fuel channel 120 extends through a respective portion of the interior 124, which can include extending through a protrusion of the set of protrusions 126. The fuel channel 120 is fluidly coupled to the aperture 118. The fuel channel 120 opens to the central channel 108 at a fuel jet of a set of fuel jets 128. Each fuel jet of the set of fuel jets 128 is provided on a respective portion of the swirler 110. For example, each fuel jet of the set of fuel jets 128 is located at a distal end 129 of a respective protrusion of the set of protrusions 126.

[0069] The swirler 110 is located in the central channel 108. At least a portion of the swirler 110 extends radially inward from the inner fuel nozzle body surface 106. Specifically, the set of helical vanes 112 extends radially inward from inner fuel nozzle body surface 106 toward the fuel nozzle centerline 104. At least a portion of the swirler 110 can be integrally formed with the fuel nozzle body 102. As a non-limiting example, the set of helical vanes 112 can be integrally formed with the fuel nozzle body 102.

[0070] The fuel nozzle assembly 100 includes a mixing length 131. The mixing length 131 is an axial distance, with respect to the fuel nozzle centerline 104, measured between a fuel jet of the set of fuel jets 128 axially nearest the fuel nozzle outlet 74 (e.g. an axially forwardmost fuel jet of the set of fuel jets 128 with respect to the fuel nozzle centerline 104) and the fuel nozzle outlet 74. The fuel nozzle assembly 100 includes a hydraulic exit diameter 135. The hydraulic exit diameter 135 is a radial distance with respect to the fuel nozzle centerline 104 that extends radially across the inner fuel nozzle body surface 106 through the fuel nozzle centerline 104. The hydraulic exit diameter135 is used to calculate a flow volume of the fuel nozzle assembly 100. A ratio of the mixing length 131 to the hydraulic exit diameter 135 is greater than or equal to 0 and less than or equal to 200. A benefit of sizing the fuel nozzle assembly 100 to have the aforementioned ratio is preventing flashback which will be described in further detail below.

[0071] During operation, a compressed air C is supplied to the fuel nozzle assembly 100. Specifically, the compressed air C is fed axially with respect to the fuel nozzle centerline 104 to the central channel 108 from an upstream portion of the turbine engine (e.g. the turbine engine 10 of FIG. 1) such as from a compressor section (e.g. the compressor section 12 of FIG. 1). At least a portion of the compressed air C within the central channel 108 flows over the outer wall 122 of each helical vane of the set of helical vanes 112. The set of helical vanes 112 imparts a swirl onto the compressed air C to define a swirled air flow S downstream of the set of helical vanes 112. The set of helical vanes 112 are sized such that the first helical vane 112a terminates radially prior to the second helical vane 112b. At least a portion of the compressed air C can flow along the fuel nozzle centerline 104 and not be swirled like the swirled air S.

[0072] During operation, a fuel F is also supplied to the fuel nozzle assembly 100. Specifically, the fuel F is supplied to the interior 124 of at least one helical vane of the set of helical vanes 112 of the swirler 110 from a fuel source exterior to the fuel nozzle assembly 100 (e.g. the fuel source 34 of FIGS. 2-3). In a non-limiting example, the fuel F flows radially with respect to the fuel nozzle centerline 104 through the fuel supply passage 117 and the aperture 118. The fuel F is then supplied to the fuel channel 120 and is emitted axially with respect to the fuel nozzle centerline 104 into the central channel 108 through the set of fuel jets 128. For purposes of illustration, the fuel F is illustrated emitting from one fuel jet of the set of fuel jets 128 located on one protrusion of the set of protrusions 126. However, it will be appreciated that the fuel F can be exhausted from more than one fuel jet of the set of fuel jets 128, each fuel jet of the set of fuel jets 128 being located on a respective protrusion of the set of protrusion 126.

[0073] The fuel F contains any suitable fuel. As a non-limiting example, the fuel F includes a gaseous fuel. Additionally or alternatively, the fuel F can include a flow of H2 fuel (e.g., 100% gaseous H2 fuel, 100% liquid H2 fuel, or H2 fuel mixed with another fuel or fluid), natural gas, ammonia. It is contemplated that the fuel F can include multiple fuels. For example, the set of fuel jets 128 can include multiple fuel jets. A first subset of the multiple fuel jets can emit a first fuel composition, and a second subset of the multiple fuel jets can emit a second fuel composition that is different from the first fuel composition. Further, the size and particular placement of the set of fuel jets 128 can be varied based on the fuel composition.

[0074] Due to the swirled air flow S downstream of the swirler 110, the fuel F and the swirled air flow S mix to form a fuel air mixture M. The fuel air mixture M is then supplied to the combustion chamber 50 (FIG. 3). In a non-limiting example, the fuel air mixture M has a fuel to air ratio of greater than or equal to 0.005 and less than or equal to 0.060. The fuel air mixture M can be a temporally uniform mixture of fuel and air. As used herein, a temporally uniform mixture can refer to a homogenous or near-homogeneous mixture of fuel and air where the fuel is evenly or nearly-evenly spread throughout the flow of air. “Nearly-evenly” refers to instances where small sections of the homogenous mixture of fuel and air includes larger concentrations of fuel or air. It will be appreciated that these small sections are negligible and defined as regions where, once the fuel air mixture M is ignited, will not cause flashback to occur or for a significant difference in temperature distribution to occur. A temporally uniform mixture of fuel and air can also refer to a mixture that at a particular location (e.g. at the fuel nozzle outlet 74) has local regions of leaner or richer fuel that are consistent over time. For example, the mixture M can consistently have a higher concentration of fuel at the fuel nozzle centerline 104 compared to at the inner fuel nozzle body surface 106, which improves stability. Alternatively, the mixture M can consistently have a high concentration of fuel at the inner fuel nozzle body surface 106 compared to at the fuel nozzle centerline 104, which reduces the risks of flashback and flame holding.

[0075] The fuel nozzle assembly 100 is especially well suited for use where the fuel F contains H2 fuel. As discussed herein, the swirled air flow S ensures a homogenous mixture of fuel and air of the fuel air mixture M, thus reducing the likelihood of pockets or concentrations of fuel to be formed within the fuel air mixture M. As discussed herein, H2 fuels have a higher burn velocity and greater chance for flashback. The elimination of or reduction of the large concentrations of fuel within the fuel air mixture M reduces the likelihood of flashback occurring by reducing the locations where the flame can spread.

[0076] Further, the use of the swirled air flow S allows for a lean-fuel mixture of the fuel air mixture M. As used herein, the term “lean mixture” refers to a fuel air mixture M with a relatively low concentration or volume of fuel. Conversely, a “rich mixture” refers to a fuel air mixture M with relatively high concentration of volume of fuel. A lean mixture of fuel and air reduces the overall NOx emissions from the turbine engine; however, a lean mixture of fuel and air can be more difficult to control within the combustion chamber 50 (FIG. 3) in comparison with the rich mixture of fuel and air. Specifically, it is more difficult to create a homogenous mixture of fuel and air when using a lean mixture. The use of the swirled air flow S ensures that the fuel and the compressed air C are uniformly or nearly uniformly mixed.

[0077] FIG. 5 is a cross-sectional view of the fuel nozzle assembly 100 taken along the line V-V in FIG. 4. The set of helical vanes 112 extends radially inward from the inner fuel nozzle body surface 106 towards the fuel nozzle centerline 104. Particularly, the set of helical vanes 112 can terminate radially prior to the fuel nozzle centerline 104 to form a gap 133 between radially opposing portions of the set of helical vanes 112. In a non-limiting example, a hydraulic diameter of the gap 133 is in a range from greater than or equal to 5% of a diameter of the swirler 110 measured perpendicular to the fuel nozzle centerline 104 and less than or equal to 20% of the diameter of the swirler 110 measured perpendicular to the fuel nozzle centerline 104.

[0078] During operation, the swirler 110 generates a first flow of swirled air 134 and a second flow of swirled air 136 from the compressed air C. The first flow of swirled air 134 and the second flow of swirled air 136 collectively form a cumulative swirled air flow S (FIG. 4). The first flow of swirled air 134 is created by the compressed air C flowing over the outer wall 122 of the set of helical vanes 112. The second flow of swirled air 136 is created by the compressed air C flowing around the set of protrusions 126.

[0079] The first flow of swirled air 134 and the second flow of swirled air 136 are each defined by a respective mass flow rate. The first flow of swirled air 134 has a larger mass flow rate than the second flow of swirled air 136. Put another way, the first flow of swirled air 134 makes up a larger proportion of a total mass flow rate of the swirled air flow S (FIG. 4) than the second flow of swirled air 136. As such, the first flow of swirled air 134 is defined as a bulk swirl while the second flow of swirled air 136 is defined as a micro swirl. The first flow of swirled air 134 and the second flow of swirled air 136 are each defined by a respective swirl number. The swirl number of the first flow of swirled air 134 is different from the swirl number of the second flow of swirled air 136. For example, the swirl number of the first flow of swirled air 134 is greater than the swirl number of the second flow of swirled air 136.

[0080] The fuel F (FIG. 4) is emitted by the fuel jet 128 into the second flow of swirled air 136. Thus, the second flow of swirled air 136 breaks up the axially flowing fuel F. The second flow of swirled air 136 then mixes and breaks up into the first flow of swirled air 134, which facilitates high mixedness (e.g. greater than or equal to 90%) of the fuel F and compressed air A ultimately forming the fuel air mixture M (FIG. 4).

[0081] The set of protrusions 126 being located within the central channel 108 away from the inner fuel nozzle body surface 106 minimizes flame holding within the fuel nozzle body 102. As the first flow of swirled air 134 and the second flow of swirled air 136 intersect with each other, the swirled air flow S (FIG. 4) is formed.

[0082] Because the central channel 108 is unobstructed along the gap 133 extending axially along the fuel nozzle centerline 104, a portion of the compressed air C flows axially along the fuel nozzle centerline 104. The portion of the compressed air C flowing axially along the fuel nozzle centerline 104 has a relatively low mixedness with the fuel F compared to the swirled airflow S, but the portion of the compressed air C flowing axially along the fuel nozzle centerline 104 can prevent a flame bubble in a combustion chamber (e.g. the combustion chamber 50 of FIG. 3) from traveling into the fuel nozzle assembly 100 and damaging the swirler 110.

[0083] FIG. 6 is a cross-sectional view of a first protrusion 126a of the set of protrusions 126 viewed along line VI-VI in FIG. 4. Although the first protrusion 126a is located on the first helical vane 112a, it will be appreciated that any of the set of helical vanes 112 can include the first protrusion 126a. It should also be understood that description of the first protrusion 126a can apply to all protrusions of the set of protrusions 126. The first protrusion 126a defines a protrusion centerline 130. The first protrusion 126a includes a tapered portion 132 which tapers towards the protrusion centerline 130. The first protrusion 126a is formed in the outer wall 122 of the first helical vane 112a, defining a portion of the interior 124 of the first helical vane 112a.

[0084] The fuel channel 120 extends through the first protrusion 126a. A first fuel jet 128a of the set of fuel jets 128 is located at the distal end 129 of the first protrusion 126a. The first fuel jet 128a opens to the central channel 108. That is, the first fuel jet 128a is located on the swirler 110 downstream of the second end 116 of the first helical vane 112a.

[0085] FIG. 7 is a cross-sectional view of a portion of an exemplary fuel nozzle assembly 200 suitable for use as the fuel nozzle assembly 48 of FIGS. 2-3. The fuel nozzle assembly 200 is similar to the fuel nozzle assembly 100 (FIGS. 4-6); therefore, like parts will be identified with like numerals increased to the 200 series with it being understood that the description of the fuel nozzle assembly 100 applies to the fuel nozzle assembly 200 unless noted otherwise.

[0086] The fuel nozzle assembly 200 includes a swirler 210 located in a central channel 208. The swirler 210 includes a helical vane 212. The helical vane 212 includes an outer wall 222 defining an interior 224.

[0087] The swirler 210 includes a protrusion 226. The protrusion 226 defines a protrusion centerline 230. The protrusion 226 includes a tapered portion 232 which tapers towards the protrusion centerline 230.

[0088] The swirler 210 includes a splitter 238. The splitter 238 is located within the interior 224 of the helical vane 212. The splitter 238 extends through and is circumscribed by the interior 224. A radially outer surface of the splitter 238 with respect to the protrusion centerline 230 can include a tapered portion 244. The tapered portion 244 can be parallel with the tapered portion 232. The splitter 238 divides the interior 224 into two channels, a fuel channel 220 and a fluid channel 240.

[0089] The swirler 210 includes a fluid channel 240. The fluid channel 240 is formed within the splitter 238. That is, the fluid channel extends through a respective portion of the splitter 238, which includes extending through a portion of the splitter 238 located within the protrusion 226. Particularly, the splitter 238 circumscribes the fluid channel 240. The fluid channel opens to the central channel 208 at a fluid jet 242. The fluid jet 242 is located at a distal end 239 of the splitter 238.

[0090] The swirler 210 includes a fuel channel 220. The fuel channel 220 extends through a respective portion of the interior 224 of the helical vane 212, which includes extending through the protrusion 226. Particularly, the fuel channel 220 is radially spaced from the fluid channel 240 with respect to the protrusion centerline 230. That is, the fuel channel 220 circumscribes the splitter 238 and the fluid channel 240 throughout the interior 224 including within the protrusion 226. The fuel channel 220 opens to the central channel 208 at a fuel jet 228. The fuel jet 228 is provided at a distal end 229 of the protrusion 226. The fuel jet 228 can be located at the same axial position as the fluid jet 242 along the protrusion centerline 230 such that the fluid jet 242 is circumscribed by the fuel jet 228 as illustrated, or the splitter 238 can axially extend beyond the fuel jet 228 with respect to the protrusion centerline 230. That is, the fluid jet 242 can be located on the protrusion 226.

[0091] During operation, a fluid L is supplied to the fluid channel 240 and a fuel, particularly the fuel F, is supplied to the fuel channel 220. The fuel jet 228 emits a flow of the fuel F and the fluid jet 242 emits a flow of the fluid L. The fluid L is at least one of compressed air, steam, atomized liquid fuel, and gaseous fuel including H2 fuel, natural gas, ammonia, or a combination thereof. The fluid L emitted by the fluid jet 242 and the fuel F emitted by the fuel jet 228 are injected into a micro swirl of compressed air (e.g. the second flow of swirled air 136 of FIG. 5) downstream of the protrusion 226. The fluid L meeting the micro swirl of compressed air allows for maximal mixing and droplet dispersion. Further, the fuel F being injected circumferentially around the fluid L does not create a flame holding region, which ultimately allows for lower NOx emissions.

[0092] In another non-limiting example, the fluid L is liquid fuel and is supplied to the fluid channel 240 while a flow of fuel F to the fuel channel 220 is turned off. The fuel channel 220 without fuel F therein acts as a thermal barrier to fluid L within the fluid channel 240, which helps prevent coking of the liquid fuel.

[0093] In another non-limiting example, the fluid L is at least one of compressed air or steam and is supplied to the fluid channel 240. The injection of compressed air or steam allows for additional mass flow and NOx quenching.

[0094] It is contemplated that the fuel channel 220 and the fluid channel 240 can be reversed from what is pictured in FIG. 7. That is, the fluid channel 240 can circumscribe the fuel channel 220 such that the fuel F is injected surrounding the fluid L.

[0095] FIG. 8 is a forward view from aft of a portion of a fuel nozzle assembly 300 suitable for use as the fuel nozzle assembly 48 of FIGS. 2-3. The fuel nozzle assembly 300 is similar to the fuel nozzle assembly 100 (FIGS. 4-6), 200 (FIG. 7); therefore, like parts will be identified with like numerals increased to the 300 series with it being understood that the description of the fuel nozzle assemblies 100, 200 applies to the fuel nozzle assembly 300 unless noted otherwise.

[0096] The fuel nozzle assembly 300 includes a fuel nozzle body 302. For purposes of illustration, the fuel nozzle body 302 is shown in phantom lines. The fuel nozzle body 302 is an annular shape and defines a fuel nozzle centerline 304. A radially inner fuel nozzle body surface 306 with respect to the fuel nozzle centerline 304 defines a perimeter of a central channel 308. The central channel 308 is disposed upstream of the fuel nozzle outlet 74 (FIG. 3) and ultimately opens to the combustion chamber 50 (FIG. 3).

[0097] The fuel nozzle assembly 300 includes a swirler 310. The swirler 310 includes a set of helical vanes 312. Each helical vane of the set of helical vanes 312 wraps circumferentially about at least a portion of the fuel nozzle centerline 304. The set of helical vanes 312 includes any number of one or more helical vanes. As a non-limiting example, the set of helical vanes 312 includes a first helical vane 312a and a second helical vane 312b. The first helical vane 312a extends axially from a second end 316a, with respect to the fuel nozzle centerline 304, and the second helical vane 312b extends axially from a second end 316b, with respect to the fuel nozzle centerline 304. In the illustrated non-limiting example, the second end 316a of the first helical vane 312a is axially aligned with the second end 316b of the second helical vane 312b. Alternatively, the second end 316a of the first helical vane 312a can be axially unaligned with the second end 316b of the second helical vane 312b.

[0098] The swirler 310 includes a vane hub 346. The vane hub 346 extends axially along the fuel nozzle centerline 304. The first helical vane 312a and the second helical vane 312b are radially separated from each other along the fuel nozzle centerline 304 by the vane hub 346. That is, each helical vane of the set of helical vanes 312 extends radially between the vane hub 346 and a respective portion of the inner fuel nozzle body surface 306 of the fuel nozzle body 302. Along the fuel nozzle centerline 304, the central channel 308 is obstructed by the vane hub 346.

[0099] During operation a compressed air C is supplied to the swirler 310 axially with respect to the fuel nozzle centerline 304. The vane hub 346 prevents the compressed air C from flowing axially straight along the fuel nozzle centerline 304 and forces the compressed air C to flow in a coil shape between adjacent surfaces of the first helical vane 312a and the second helical vane 312b around the vane hub 346. By preventing the compressed air C from flowing axially along the fuel nozzle centerline 304, greater mixedness occurs between the compressed air C and a fuel (e.g. the fuel F of FIGS. 4-7), a fluid (e.g. the fluid L of FIG. 7), or a combination thereof compared to a swirler that has an unobstructed fuel nozzle centerline (e.g. the swirler 110 of FIGS. 4-5), which results in correspondingly lower emissions. Particularly, in configurations where a flame bubble can be contained within a combustion chamber (e.g. the combustion chamber 50 of FIG. 3) without an axial flow with respect to the fuel nozzle centerline 304 of a portion of the compressed air C or in configurations where a swirl number of the swirled air flow S is sufficiently low that no flame bubble if formed, all of the compressed air C becomes swirled as it flows over the set of helical vanes 312.

[0100] FIG. 9 is a schematic side view depicting a fuel nozzle assembly 400 suitable for use as the fuel nozzle assembly 48 of FIGS. 2-3. The fuel nozzle assembly 400 is similar to the fuel nozzle assembly 100 (FIGS. 4-6), 200 (FIG. 7), 300 (FIG. 8); therefore, like parts will be identified with like numerals increased to the 400 series with it being understood that the description of the fuel nozzle assemblies 100, 200, 300 applies to the fuel nozzle assembly 400 unless noted otherwise.

[0101] The fuel nozzle assembly 400 includes a fuel nozzle body 402. The fuel nozzle body 402 is an annular shape and defines a fuel nozzle centerline 404. A radially inner fuel nozzle body surface 406 with respect to the fuel nozzle centerline 404 defines a central channel 408. The central channel 408 extends from an air inlet 448. The air inlet 448 can be a single continuous aperture extending through the fuel nozzle body 402, or it can be a plurality of apertures spaced about the fuel nozzle body 402. The central channel 408 is disposed upstream of the fuel nozzle outlet 74 and opens to the combustion chamber 50 (FIG. 3).

[0102] The central channel 408 is split into at least two sections: a supply passage 450 and a mixing tube 452. The supply passage 450 extends axially with respect to the fuel nozzle centerline 404 from the air inlet 448 to the mixing tube 452. The mixing tube 452 extends axially with respect to the fuel nozzle centerline 404 from the supply passage 450 downstream. Further delineation between the supply passage 450 and the mixing tube 452 with respect to flows of fluids within the supply passage 450 and the mixing tube 452 will be described in further detail below

[0103] The fuel nozzle assembly 400 includes a centerbody 454. The centerbody 454 extends axially through the supply passage 450 of the central channel 408 along the fuel nozzle centerline 404. That is, at least a portion of the centerbody 454 is spaced radially inwardly from the inner fuel nozzle body surface 406 with respect to the fuel nozzle centerline 404. The centerbody 454 is one of coupled to or integrally formed with a respective portion of the fuel nozzle body 402. The centerbody 454 includes a radially outer centerbody surface 456 and a radially inner centerbody surface 458 with respect to the fuel nozzle centerline 404.

[0104] The centerbody 454 includes a centerbody channel 460. The centerbody channel 460 extends through the centerbody 454 and is circumscribed by the inner centerbody surface 458. The centerbody channel 460 originates at a centerbody inlet 462 and terminates at a set of centerbody fluid jets 464 opening into a portion of the central channel 408 downstream of the swirler 410 (e.g. into the mixing tube 452). The number of centerbody fluid jets included in the set of centerbody fluid jets 464 is not limited.

[0105] The fuel nozzle assembly 400 includes a swirler 410. The swirler 410 includes a set of helical vanes 412. The number of helical vanes included in the set of helical vanes 412 is not limited. Each helical vane of the set of helical vanes 412 extends axially between a first end 414 and a second end 416, with respect to the fuel nozzle centerline 404. Some or all of the helical vanes of the set of helical vanes 412 are at least partially hollow such that a fuel F can flow therethrough.

[0106] The set of helical vanes 412 can include a subset of first helical vanes 412a. The number of first helical vanes included in the subset of first helical vanes 412a is not limited. The subset of first helical vanes 412a protrudes radially outwardly with respect to the fuel nozzle centerline 404 from the outer centerbody surface 456 away from the fuel nozzle centerline 404. Each first helical vane of the subset of first helical vanes wraps circumferentially around the centerbody 454. In a non-limiting example, the set of helical vanes includes only the subset of first helical vanes 412a.

[0107] The set of helical vanes 412 can include a subset of second helical vanes 412b. The number of second helical vanes included in the subset of second helical vanes 412b is not limited. The subset of second helical vanes 412b protrudes radially inward with respect to the fuel nozzle centerline 404 from the inner fuel nozzle body surface 406 towards the fuel nozzle centerline 404. In a non-limiting example, the set of helical vanes 412 includes only the subset of second helical vanes 412b. In another non-limiting example, the set of helical vanes 412 includes both the subset of first helical vanes 412a and the subset of second helical vanes 412b.

[0108] Each helical vane of the subset of first helical vanes 412a extends a respective first axial length 423 with respect to the fuel nozzle centerline 404 between the respective first end 414 and the respective second end 416. Each helical vane of the subset of second helical vanes 412b extends a respective second axial length 425 with respect to the fuel nozzle centerline 404 between the respective first end 414 and the respective second end 416 of the second helical vane 412b. In the illustrated non-limiting example, the first axial length 423 of each helical vane of the subset of first helical vanes 412a is equal to the second axial length 425 of each helical vane of the subset of second helical vanes 412b. Alternatively, the first axial length 423 of each helical vane of the subset of first helical vanes 412a need not be the same. Alternatively still, the second axial length 425 of each helical vane of the subset of second helical vanes 412b need not be the same. Additionally or alternatively, the first axial length 423 of a helical vane of the subset of first helical vanes 412a can be different from the second axial length 425 of a helical vane of the subset of second helical vanes 412b. It should be appreciated that the fuel nozzle assembly 100 of FIGS. 4-6 is similar to the fuel nozzle assembly 400 of FIG. 9 in that the first helical vane 112a extends a first axial length between the first end 114 and the second end 116 of the first helical vane 112a, the second helical vane 112b extends a second axial length between the first end 114 and the second end 116 of the second helical vane 112b, and in the illustrated non-limiting example of FIGS. 4-6, the first axial length is equal to the second axial length. Alternatively, the first axial length of the first helical vane 112a can be different from the second axial length of the second helical vane 112b.

[0109] The swirler 410 includes at least one protrusion 426. The protrusion 426 is a hollow protrusion extending from any suitable portion of the swirler 410. In a non-limiting example, the protrusion 426 is located on a surface of a helical vane of the set of helical vanes 412 and extends axially forward (e.g. towards the combustion chamber 50, FIG. 3).

[0110] During operation, a compressed air C, a fuel F, and a fluid L are supplied to the fuel nozzle assembly 400. The fuel F is, for example, H2, natural gas, or a combination thereof. The fluid L is at least one of compressed air, steam, atomized liquid fuel, and gaseous fuel.

[0111] The compressed air C is supplied to the swirler 410 axially with respect to the fuel nozzle centerline 404. The compressed air C flows through the supply passage 450 and over exposed surfaces of the set of helical vanes that are not attached to at least one of the inner fuel nozzle body surface 406 and the outer centerbody surface 456. Mounting the set of helical vanes 412 within the supply passage 450 such that some surfaces of the set of helical vanes 412 are exposed ensures a high velocity of the compressed air C flowing through the supply passage 450, which prevents flame holding. The compressed air C is then emitted to the mixing tube 452. High turbulence is generated as the compressed air C flows over the exposed surfaces of the set of helical vanes 412, creating a high turbulence region in the mixing tube 452.

[0112] In the non-limiting embodiment where the set of helical vanes 412 includes only the subset of first helical vanes 412a, the compressed air C with axial velocity relative to the fuel nozzle centerline 404 flows along the inner fuel nozzle body surface 406 to maintain a high axial velocity of the compressed air C when entering the mixing tube 452, which prevents flashback and flame holding.

[0113] The fuel F can be supplied radially with respect to the fuel nozzle centerline 404 and flow within at least one helical vane of the set of helical vanes 412 before being emitted to the mixing tube 452. The fuel F then meets the compressed air C in the high turbulence region of the mixing tube 452, which facilitates mixing of the compressed air C and the fuel F. Additionally or alternatively, the fuel F can be supplied axially through the centerbody channel 460 before being emitted by the set of centerbody fluid jets 464 to the mixing tube 452.

[0114] The fluid L can be supplied axially with respect to the fuel nozzle centerline 404 through the centerbody channel 460 before being emitted by the set of centerbody fluid jets 464 to the mixing tube 452. Additionally or alternatively, the fluid L can flow within at least one helical vane of the set of helical vanes 412. In a non-limiting example, the fuel F flows within some of the helical vanes of the set of helical vanes 412 and the fluid L flows within some of the helical vanes of the set of helical vanes 412 in an alternating arrangement.

[0115] It is contemplated that the supply of the fuel F and the fluid L can be reversed from what is pictured in FIG. 9. That is, the fuel F supplied axially through the centerbody channel 460 and the fluid L can be supplied radially with respect to the fuel nozzle centerline 404 and flow within at least one helical vane of the set of helical vanes 412.

[0116] In the mixing tube 452, the fuel F, the compressed air C, and the fluid L come together and mix to form a fuel air mixture M. The fuel air mixture M is then supplied to the combustion chamber 50 (FIG. 3).

[0117] FIG. 10 is a cross-sectional view of the fuel nozzle assembly 400 taken along the line X-X in FIG. 9 illustrating the effects of the swirler 410. Particularly, the result of the compressed air C (FIG. 9) flowing over exposed surfaces of the set of helical vanes 412 is a set of swirled air flows 466 downstream of the swirler 410.

[0118] The Subset of First Helical Vanes 412a and the subset of second helical vanes 412b can be oriented such that the compressed air C flowing over exposed surfaces of the set of helical vanes 412 swirls in the same direction. Alternatively, the subset of first helical vanes 412a and the subset of second helical vanes 412b can be oriented such that the compressed air C flowing over the subset of first helical vanes 412a swirls in a direction opposite to the compressed air C flowing over the subset of the second helical vanes 412b. Such a configuration can further improve mixing of the fuel F and the compressed air C in the mixing tube 452 (FIG. 9).

[0119] To the extent not already described, the different features and structures of the various embodiments can be used in combination, or in substitution with each other as desired. That one feature is not illustrated in all the embodiments is not meant to be construed that it cannot be so illustrated but is done for brevity of description. Thus, the various features of the different embodiments can be mixed and matched as desired to form new embodiments, whether or not the new embodiments are expressly described. All combinations or permutations of features described herein are covered by this disclosure. In a non-limiting example, a swirler can include a plurality of helical vanes, where a helical vane includes a splitter within it as depicted in FIG. 7 and another helical vane does not include a splitter within it as depicted in FIG. 6. Such a configuration would be advantageous in an environment where multiple different fuels can utilized. For example, a flow of gaseous fuel would be best suited for a fuel passage without a splitter, while a flow of liquid fuel would be best suited for a helical vane including a splitter such that the liquid fuel can be surrounded by air. By including a combination of helical vanes with and without a splitter, a gaseous fuel and a liquid fuel can be used separately or in combination.

[0120] This written description uses examples to describe aspects of the disclosure described herein, including the best mode, and also to enable any person skilled in the art to practice aspects of the disclosure, including making and using any devices or systems and performing any incorporated methods. The patentable scope of aspects of the disclosure is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

[0121] Further aspects are provided by the subject matter of the following clauses:

[0122] A combustion section for a turbine engine, the combustion section comprising a wall at least partially forming a combustion chamber, and a fuel nozzle extending through a respective portion of the wall, the fuel nozzle having a fuel nozzle body defining a central channel and a fuel nozzle centerline, the central channel opening to the combustion chamber at a fuel nozzle outlet, and a swirler provided along the fuel nozzle body and extending into the central channel, the swirler having a helical vane wrapped circumferentially about the fuel nozzle centerline greater than or equal to π / 2 radians between a first end and a second end, axially opposing the first end.

[0123] The combustion section of any preceding clause, wherein the fuel nozzle comprises a fuel channel extending through the helical vane and having a fuel jet opening to a portion of the central channel downstream of the second end.

[0124] The combustion section of any preceding clause, wherein the fuel jet is located on the swirler.

[0125] The combustion section of any preceding clause, wherein the swirler comprises a protrusion that is a localized raised surface of an outer wall of the helical vane, with the fuel jet being located along a distal end of the protrusion.

[0126] The combustion section of any preceding clause, wherein the fuel nozzle comprises a fluid channel having a fluid jet located on the protrusion and opening to a portion of the central channel downstream of the swirler.

[0127] The combustion section of any preceding clause, wherein the fuel channel circumscribes the fluid channel within the protrusion.

[0128] The combustion section of any preceding clause, wherein the fuel channel emits a flow of gaseous fuel through the fuel jet, and the fluid channel emits one of a flow of liquid fuel, or a flow of steam through the fluid jet.

[0129] The combustion section of any preceding clause, wherein the helical vane is a plurality of helical vanes, each of the plurality of helical vanes terminating radially prior to the fuel nozzle centerline to form a gap between radially opposing portions of the plurality of helical vanes.

[0130] The combustion section of any preceding clause, wherein a hydraulic diameter of the gap is in a range from greater than or equal to 5% of a diameter of the swirler measured perpendicular to the fuel nozzle centerline and less than or equal to 20% of the diameter of the swirler measured perpendicular to the fuel nozzle centerline.

[0131] The combustion section of any preceding clause, wherein the swirler generates a first flow of swirled air downstream of the second end, the swirler comprises a protrusion that is a localized raised surface of an outer wall of the helical vane, with the protrusion generating a second flow of swirled air downstream of the second end, and the first flow of swirled air and the second flow of swirled air collectively form a cumulative flow of swirled air within the central channel, with the first flow of swirled air having a larger mass flow rate than the second flow of swirled air.

[0132] The combustion section of any preceding clause, wherein the helical vane is included in a plurality of helical vanes, with each helical vane of the plurality of helical vanes extending from a respective portion of the fuel nozzle body.

[0133] The combustion section of any preceding clause, wherein the swirler comprises a vane hub located within the central channel, with each helical vane of the plurality of helical vanes extending radially between the vane hub and the respective portion of the fuel nozzle body.

[0134] The combustion section of any preceding clause, wherein the fuel nozzle body comprises an inner surface defining a perimeter of the central channel, and the fuel nozzle further comprises a centerbody spaced radially inwardly from the inner surface and extending through a respective portion of the central channel.

[0135] The combustion section of any preceding clause, wherein the helical vane extends outwardly from the centerbody.

[0136] The combustion section of any preceding clause, wherein the helical vane is included in a plurality of helical vanes, the plurality of helical vanes having a set of first helical vanes extending outwardly from the centerbody, and a set of second helical vanes extending inwardly from the inner surface.

[0137] The combustion section of any preceding clause, wherein the centerbody further comprises a set of centerbody fluid jets opening to a portion of the central channel downstream of the swirler.

[0138] The combustion section of any preceding clause, wherein the wall includes a bluff area defined as a surface area of the wall confronting the combustion chamber, the fuel nozzle having a flow area defined as a surface area of the fuel nozzle outlet, and a ratio between the bluff area and the flow area is greater than or equal to 0.01 and less than or equal to 10.

[0139] The combustion section of any preceding clause, wherein the fuel nozzle is configured to feed a fuel air mixture to the combustion chamber, the fuel air mixture having a fuel to air ratio of greater than or equal to 0.005 and less than or equal to 0.060.

[0140] The combustion section of any preceding clause, wherein the fuel nozzle comprises an axially forwardmost fuel jet configured to inject a flow of fuel into the central channel, a mixing length is defined as an axial distance with respect to the fuel nozzle centerline between the axially forwardmost fuel jet and the fuel nozzle outlet, the fuel nozzle outlet defines a hydraulic exit diameter, and a ratio of the mixing length to the hydraulic exit diameter is greater than or equal to 0 and less than or equal to 200.

[0141] The combustion section of any preceding clause, wherein the fuel nozzle comprises a fuel channel opening to the central channel at a fuel jet, and the fuel channel is configured to feed a flow of hydrogen-containing fuel to the central channel.

[0142] A combustion section for a turbine engine, the combustion section comprising a wall at least partially forming a combustion chamber, a fuel nozzle that opens to the combustion chamber through the wall, the fuel nozzle comprising a fuel nozzle body defining a central channel exhausting into the combustion chamber at a fuel nozzle outlet, and a swirler provided within the central channel, the swirler having a body centerline and a helical vane extending from the body centerline, the helical vane wrapped circumferentially about the body centerline greater than or equal to π / 2 radians between a first end and a second end, axially opposing the first end, of the helical vane.

[0143] A combustion section for a turbine engine, the combustion section comprising a wall at least partially forming a combustion chamber, and a fuel nozzle that opens to the combustion chamber through the wall, the fuel nozzle comprising a fuel nozzle body including a central channel exhausting into the combustion chamber at a fuel nozzle outlet, the central channel having a centerline, a first swirler provided within the central channel, and a second swirler provided within the second channel axially forward of the first swirler.

[0144] A combustion section for a turbine engine, the combustion section comprising a wall at least partially forming a combustion chamber, and a fuel nozzle that opens to the combustion chamber through the wall, the fuel nozzle comprising a fuel nozzle body including a central channel exhausting into the combustion chamber at a fuel nozzle outlet, and a swirler provide within the central channel, the swirler including a body centerline, an upstream portion and a downstream portion provided axially aft of the upstream portion, the swirler converging radially inward from the upstream portion and to the downstream portion.

[0145] A combustion section for a turbine engine, the combustion section comprising a wall at least partially forming a combustion chamber, and a fuel nozzle that opens to the combustion chamber through the wall, the fuel nozzle comprising a fuel nozzle body including a central channel exhausting into the combustion chamber at a fuel nozzle outlet, the central channel having a centerline, and a swirler provide within the central channel, the swirler including a body centerline, the body centerline intersecting the centerline at a non-zero acute angle.

[0146] A turbine engine comprising a compression section, a combustion section, and a turbine section in serial flow arrangement, the combustion section comprising a wall at least partially forming a combustion chamber, and a fuel nozzle that opens to the combustion chamber through the wall, the fuel nozzle comprising a fuel nozzle body including a central channel exhausting into the combustion chamber at a fuel nozzle outlet, the central channel having a centerline, a first swirler provided within the central channel, the first swirler having a first body centerline and a first helical vane extending circumferentially in a first circumferential direction about the first body centerline, and a second swirler provided within the central channel, the second swirler having a second body centerline and a second helical vane extending circumferentially in a second circumferential direction about the second body centerline, the second circumferential direction being opposite the first circumferential direction.

[0147] A combustion section for a turbine engine, the combustion section comprising a wall at least partially forming a combustion chamber, and a fuel nozzle that opens to the combustion chamber through the wall, the fuel nozzle comprising a fuel nozzle body including a central channel exhausting into the combustion chamber at a fuel nozzle outlet, and a swirler provided within the central channel, the swirler having a fuel channel opening at a fuel orifice provided along the swirler.

[0148] A combustion section for a turbine engine, the combustion section comprising a wall at least partially forming a combustion chamber, and a fuel nozzle that opens to the combustion chamber through the wall, the fuel nozzle comprising a fuel nozzle body including a central channel exhausting into the combustion chamber at a fuel nozzle outlet, and a swirler provide within the central channel, the swirler including a body centerline, an upstream end, a downstream end provided axially aft of the upstream end, and a fuel channel, the fuel channel exhausting into the central channel at a fuel orifice provided along the swirler axially between the upstream end and the downstream end of the swirler.

[0149] A combustion section for a turbine engine, the combustion section comprising a wall at least partially forming a combustion chamber, and a fuel nozzle that opens to the combustion chamber through the wall, the fuel nozzle comprising a fuel nozzle body including a central channel exhausting into the combustion chamber at a fuel nozzle outlet, and a swirler provide within the central channel, the swirler including a body centerline, and a vortex generator provided along the swirler, the vortex generator configured to create a pair of opposing vortices on along circumferentially opposing sides of the vortex generator.

[0150] A combustion section for a turbine engine, the combustion section comprising a wall at least partially forming a combustion chamber, and a fuel nozzle that opens to the combustion chamber through the wall, the fuel nozzle comprising a fuel nozzle body including a central channel exhausting into the combustion chamber at a fuel nozzle outlet, the central channel having a centerline, a swirler provide within the central channel, and a fuel supply channel exhausting into the central channel at a fuel outlet, the fuel supply channel being oriented such that a flow of fuel exhausted into the central channel through the fuel supply channel is directed towards the swirler. A combustion section for a turbine engine, the combustion section comprising a wall at least partially forming a combustion chamber, and a fuel nozzle that opens to the combustion chamber through the wall, the fuel nozzle comprising a fuel nozzle body defining a central channel exhausting into the combustion chamber at a fuel nozzle outlet, the central channel having a centerline, the fuel nozzle body including an interior wall extending through a respective portion of the central channel to define a swirler channel between eth interior wall and a confronting portion of the fuel nozzle body, and a swirler provided within the swirler channel.

[0151] A combustion section for a turbine engine, the combustion section comprising a wall at least partially forming a combustion chamber, and a fuel nozzle that opens to the combustion chamber through the wall, the fuel nozzle comprising a fuel nozzle body defining a central channel exhausting into the combustion chamber at a fuel nozzle outlet, and a swirler provided within the central channel, the swirler having a body centerline, the swirler being moveable within the central channel about a plane of movement.

[0152] A combustion section for a turbine engine, the combustion section comprising a wall at least partially forming a combustion chamber, and a fuel nozzle that opens to the combustion chamber through the wall, the fuel nozzle comprising a fuel nozzle body including a central channel exhausting into the combustion chamber at a fuel nozzle outlet, and a swirler provide within the central channel, the swirler including a body centerline, a first vane and a second vane, the first vane and the second vane each extending axially between a first end and a second end with the second edge of the first vane being axially offset from the second edge of the second vane.

[0153] A combustion section for a turbine engine, the combustion section comprising a wall at least partially forming a combustion chamber, and a fuel nozzle that opens to the combustion chamber through the wall, the fuel nozzle comprising a fuel nozzle body inkling a central channel exhausting into the combustion chamber at a fuel nozzle outlet, and a swirler provide within the central channel, the swirler including a body centerline, and a vane extending axially between a first end and a second end, with the first end axially coinciding with a portion of the dome wall.

[0154] The combustion section of any preceding clause, wherein the swirler includes at least two helical vanes forming at least a double helix.

[0155] The combustion section of any preceding clause, wherein the second end of a first vane of the at least two helical vanes is axially spaced an axial distance, with respect to the body centerline, from the second end of a second vane of the at least two helical vanes.

[0156] The combustion section of any preceding clause, wherein the first end of the first helical vane axially corresponds to the first end of the second helical vane.

[0157] The combustion section of any preceding clause, wherein the first helical vane is defined by a circumferential thickness, with respect to the body centerline, and the second end of the first helical vane is axially offset a length from the second end of the second helical vane, the length being greater than 0 times and less than or equal to 20 times the circumferential thickness.

[0158] The combustion section of any preceding clause, wherein the at least two helical vanes includes more than two helical vanes.

[0159] The combustion section of any preceding clause, wherein the swirler includes two helical vanes.

[0160] The combustion section of any preceding clause, wherein the swirler includes four helical vanes.

[0161] The combustion section of any preceding clause, wherein the swirler extends a total axial distance along the body centerline, with the axial distance being greater than or equal to 0% and less than or equal to 50% of the total axial distance.

[0162] The combustion section of any preceding clause, wherein the first end and the second end of a first helical vane of the at least two helical vanes axially corresponds to the first end and the second end of a second helical vane of the at least two helical vanes.

[0163] The combustion section of any preceding clause, wherein the fuel nozzle includes a fuel channel extending through a portion of the swirler, the fuel channel including a fuel orifice opening into the central channel and being provided along the swirler.

[0164] The combustion section of any preceding clause, wherein the fuel channel extends along the body centerline.

[0165] The combustion section of any preceding clause, wherein the fuel orifice is included within a set of fuel orifices, the fuel channel includes a main channel and a set of branches branching from respective portions of the main channel and opening to the central channel at a respective fuel orifice for the set of fuel orifices.

[0166] The combustion section of any preceding clause, wherein the helical vane is included within at least two helical vanes, with each helical vane of the set of helical vanes including a respective portion of the set of branches.

[0167] The combustion section of any preceding clause, wherein the fuel orifice is included in a plurality of fuel orifices opening into the central channel along the swirler.

[0168] The combustion section of any preceding clause, wherein the plurality of fuel orifices are provided axially between a first end and a second end of the swirler, the second end being downstream of the first end.

[0169] The combustion section of any preceding clause, wherein the fuel orifice is provided along the second end of the helical vane.

[0170] The combustion section of any preceding clause, wherein the fuel orifice is provided along a portion of the helical vane axially between the first end and the second end.

[0171] The combustion section of any preceding clause, wherein the fuel orifice is provided along the body centerline.

[0172] The combustion section of any preceding clause, wherein the helical vane includes at least two helical vanes, and the fuel orifice includes a plurality of fuel orifices, with each second end of the at least two helical vanes having at least one fuel orifice of the plurality of fuel orifices.

[0173] The combustion section of any preceding clause, wherein the swirler is a first swirler included in a set of swirlers, the first swirler including the helical vane wrapped in a first circumferential direction, with respect to the body centerline of the first swirler, and a second swirler includes the helical vane wrapped in a second circumferential direction, opposite the first circumferential direction, with respect to the body centerline of the second swirler.

[0174] The combustion section of any preceding clause, wherein the first swirler is provided downstream the second swirler.

[0175] The combustion section of any preceding clause, wherein an upstream end of the first swirler touches a downstream end of the second swirler.

[0176] The combustion section of any preceding clause, wherein the body centerline of the first swirler is aligned with the body centerline of the second swirler.

[0177] The combustion section of any preceding clause, wherein the first swirler is provided radially adjacent to the second swirler, with respect to the body centerline of the first swirler.

[0178] The combustion section of any preceding clause, wherein the fuel nozzle includes an interior wall extending through the central channel and splitting the central channel into a first swirler channel and a second swirler channel.

[0179] The combustion section of any preceding clause, wherein the first swirler is provided within the first swirler channel and the second swirler is provided within the second swirler channel.

[0180] The combustion section of any preceding clause, wherein the first swirler is provide within a plurality of first swirlers provided within the first swirler channel.

[0181] The combustion section of any preceding clause, wherein each swirler of the first plurality of swirlers is oriented to direct a flow of compressed air in a first circumferential direction.

[0182] The combustion section of any preceding clause, wherein at least one swirler of the first plurality of swirlers is oriented to direct a flow of compressed air in a first circumferential direction, and at least one swirler of the of the first plurality of swirlers is oriented to direct a flow of compressed air in a second circumferential direction, opposite the first circumferential direction.

[0183] The combustion section of any preceding clause, wherein the first plurality of swirler alternately direct the flow of compressed air in the first circumferential direction and the second circumferential direction.

[0184] The combustion section of any preceding clause wherein the first plurality of swirlers non-alternately direct the flow of compressed air in the first circumferential direction and the second circumferential direction.

[0185] The combustion section of any preceding clause, wherein the set of swirlers include a first plurality of swirlers provided within the first swirler channel, with each swirler in the first plurality of swirlers including the helical vane wrapped in the first circumferential direction, and a second plurality of swirlers provided within the second swirler channel, with each swirler in the second plurality of swirlers including the helical vane wrapped in the second circumferential direction.

[0186] The combustion section of any preceding clause, wherein the first swirler channel and the second swirler channel are rectangular.

[0187] The combustion section of any preceding clause, wherein the first swirler channel and the second swirler channel are circular.

[0188] The combustion section of any preceding clause, wherein the fuel nozzle includes an interior wall extending through the central channel and splitting the central channel into a first swirler channel and a second swirler channel, the first swirler being provided within the first swirler channel and the second swirler being provided within the second swirler channel.

[0189] The combustion section of any preceding clause, wherein the interior wall extends into the central channel to the fuel nozzle outlet.

[0190] The combustion section of any preceding clause, wherein the fuel nozzle includes a fuel channel orifice opening to the central channel at a fuel orifice, the fuel channel being at least partially formed within the interior wall.

[0191] The combustion section of any preceding clause, wherein the fuel channel directs a flow of fluid radially inward, with respect to the body centerline of the swirler.

[0192] The combustion section of any preceding clause, wherein at least a portion of the fuel channel is provided within the fuel nozzle body.

[0193] The combustion section of any preceding clause, wherein the swirler includes a vortex generator provided along the helical vane.

[0194] The combustion section of any preceding clause, wherein the vortex generator is one of a counter-rotating vortex generator, a double-sided wedge, wheeler, wing, winglet, Kuethe, wishbone, hairpin, lobed, wave-type, or any combination thereof.

[0195] The combustion section of any preceding clause, wherein the vortex generator is included within a plurality of vortex generators spaced along the swirler.

[0196] The combustion section of any preceding clause, wherein a first vortex generator of the plurality of vortex generators is axially offset from a second vortex generator of the plurality of vortex generators.

[0197] The combustion section of any preceding clause, wherein the swirler converges radially inward, with respect to the body centerline, from an upstream portion and to a downstream portion of the swirler.

[0198] The combustion section of any preceding clause, wherein the upstream portion is an upstream end and the downstream portion is a downstream end.

[0199] The combustion section of any preceding clause, wherein the swirler constantly converges from the upstream portion and to the downstream portion.

[0200] The combustion section of any preceding clause, wherein the swirler non-constantly converges from the upstream portion and to the downstream portion.

[0201] The combustion section of any preceding clause, wherein the swirler is included within a set of swirlers including a first swirler and a second swirler.

[0202] The combustion section of any preceding clause, wherein the swirler is included in a plurality of swirlers, with at least one swirler of the plurality of swirlers configured to direct a flow of compressed air in a first circumferential direction, and a second swirler of the plurality of swirlers configured to direct a flow of compressed air in a second circumferential direction, opposite the first circumferential direction.

[0203] The combustion section of any preceding clause, wherein the fuel nozzle body includes a nozzle centerline, and the swirler is axially offset from or coincides with the fuel nozzle outlet.

[0204] The combustion section of any preceding clause, wherein swirler terminates at the fuel nozzle outlet.

[0205] The combustion section of any preceding clause, wherein the swirler is included in a plurality of swirlers, with each swirler terminating at a respective portion of the fuel nozzle outlet.

[0206] The combustion section of any preceding clause, wherein the swirler is moveable.

[0207] The combustion section of any preceding clause, wherein the swirler is axially moveable with respect to the body centerline.

[0208] The combustion section of any preceding clause, wherein the swirler is circumferentially moveable about the body centerline.

[0209] The combustion section of any preceding clause, wherein the swirler is moveable through a flow of compressed air flowing over the swirler.

[0210] The combustion section of any preceding clause, wherein the swirler is moveable through an actuator.

[0211] The combustion section of any preceding clause, wherein the actuator includes a linkage system and a motor, the linkage system coupling the motor and the swirler.

[0212] The combustion section of any preceding clause, wherein the swirler is included within a plurality of swirlers, with the linkage system being coupled to two or more swirlers of the plurality of swirlers.

[0213] The combustion section of any preceding clause, wherein the swirler is a first swirler included within a set of swirlers, the set of swirlers including at least one static swirler.

[0214] The combustion section of any preceding clause, wherein the swirler includes at least two vanes forming a double helix.

[0215] The combustion section of any preceding clause, wherein the swirler is axially and circumferentially moveable with respect to the body centerline.

[0216] The combustion section of any preceding clause, wherein the swirler is included in a plurality of swirlers including a first set of swirlers and a second set of swirlers.

[0217] The combustion section of any preceding clause, wherein the first set of swirlers are independently moveable with respect to the second set of swirlers.

[0218] The combustion section of any preceding clause, wherein the first set of swirlers is moveable via a first actuator, and the second set of swirlers is moveable via a second actuator.

[0219] The combustion section of any preceding clause, wherein the first set of swirlers are moveable and the second set of swirlers are static.

[0220] The combustion section of any preceding clause, wherein the first set of swirlers are moveable in a first circumferential direction and the second set of swirlers are moveable in a second circumferential direction, opposite the first circumferential direction.

[0221] The combustion section of any preceding clause, wherein the swirler is moveable at varying speeds based on a load condition of the combustion section.

[0222] The combustion section of any preceding clause, wherein the swirler is radially moveable.

[0223] The combustion section of any preceding clause, wherein the swirler is moveable about two or more planes of movement.

[0224] The combustion section of any preceding clause, wherein the fuel nozzle further comprises a fuel channel.

[0225] The combustion section of any preceding clause, wherein the fuel channel is oriented such that a flow of fuel exiting the fuel channel contacts the swirler and causes the swirler to move.

[0226] The combustion section of any preceding clause, wherein the swirler is circumferentially moveable about the body axis.

[0227] The combustion section of any preceding clause, wherein a variation of a momentum of the flow of fuel causes the swirler to move at varying speeds, with a higher momentum causing the swirler to move faster than a lower momentum.

[0228] The combustion section of any preceding clause, wherein the swirler comprises a fuel channel opening along the swirler at a fuel orifice.

[0229] The combustion section of any preceding clause, wherein the fuel orifice is oriented to cause the swirler to move.

[0230] The combustion section of any preceding clause, wherein the swirler includes at least one of a vortex generator, a wall, or an airfoil configured to cause the swirler to move.

[0231] The combustion section of any preceding clause, wherein the swirler is axially moveable to vary a mixing length of the fuel nozzle.

[0232] The combustion section of any preceding clause, wherein the mixing length is maximized during a high-load condition of the combustion section.

[0233] The combustion section of any preceding clause, wherein the mixing length is minimized during a low-load condition of the combustion section.

[0234] The combustion section of any preceding clause, wherein the swirler is included in a plurality of swirlers, with a projection of the body centerline of at least two swirlers of the plurality of swirlers intersecting at an intersection point.

[0235] The combustion section of any preceding clause, wherein the intersection point is provided within the central channel.

[0236] The combustion section of any preceding clause, wherein the central channel includes a nozzle centerline, and a projection of the body centerline from a downstream end of the swirler intersects the nozzle centerline at a swirler angle.

[0237] The combustion section of any preceding clause, wherein the swirler angle has an absolute value of greater than or equal to 120 degrees and less than or equal to 180 degrees.

[0238] The combustion section of any preceding clause, wherein the fuel nozzle comprises a fuel channel orifice opening to the central channel at a fuel orifice.

[0239] The combustion section of any preceding clause, wherein the fuel orifice is provided downstream of the swirler.

[0240] The combustion section of any preceding clause, wherein the fuel channel receives a flow of hydrogen fuel.

[0241] The combustion section of any preceding clause, wherein the central channel includes a nozzle centerline, and the fuel nozzle body includes a conic section defined by a region of the fuel nozzle body that converges radially inward towards the nozzle centerline.

[0242] The combustion section of any preceding clause, wherein the fuel channel orifice is provided along the conic surface.

[0243] The combustion section of any preceding clause, wherein the fuel nozzle orifice exhausts a flow of fluid axially towards the swirler, with respect to the centerline.

[0244] The combustion section of any preceding clause, wherein the wall is a dome wall.

[0245] The turbine engine of any preceding clause, wherein the second swirler is provided axially forward of the first swirler with respect to the centerline.

[0246] The combustion section of any preceding clause, wherein the swirler has a body centerline with at least a portion of the fuel channel extending along the body centerline.

[0247] The combustion section of any preceding clause, wherein the swirler includes a helical vane wrapping circumferentially about the body axis.

[0248] The combustion section of any preceding clause, wherein the fuel orifice is spaced radially outward from the body centerline.

[0249] The combustion section of any preceding clause, wherein the swirler extends between a first end and a second end downstream of the first end, with the fuel orifice being located along the second end.

[0250] The combustion section of any preceding clause, wherein the swirler extends between a first end and a second end downstream of the first end, with the fuel orifice being located between the first end and the second end.

[0251] The combustion section of any preceding clause, wherein the swirler is circumferentially moveable about the body axis.

[0252] The combustion section of any preceding clause, wherein the fuel orifice is oriented to cause the swirler to move circumferentially about the body axis when a flow of fuel is emitted from the fuel orifice.

[0253] The combustion section of any preceding clause, wherein the fuel outlet is provided axially aft of the swirler.

[0254] The combustion section of any preceding clause, wherein the fuel outlet is axially aligned with a respective portion of the swirler.

[0255] The combustion section of any preceding clause, wherein the fuel nozzle comprises a fuel supply channel extending through the interior wall.

[0256] The combustion section of any preceding clause, wherein the swirler channel is an annular channel.

[0257] The combustion section of any preceding clause, wherein the plane of movement is axially with respect to the body centerline.

[0258] The combustion section of any preceding clause, wherein the plane of movement is circumferentially with respect to the body centerline.

[0259] The combustion section of any preceding clause, wherein the swirler is moveable through an actuator.

[0260] The combustion section of any preceding clause, wherein the swirler is a first swirler included within a set of swirlers, the set of swirlers including ga second swirler that is stationary.

Claims

1. A combustion section for a turbine engine, the combustion section comprising:a wall at least partially forming a combustion chamber; anda fuel nozzle extending through a respective portion of the wall, the fuel nozzle having:a fuel nozzle body defining a central channel and a fuel nozzle centerline, the central channel opening to the combustion chamber at a fuel nozzle outlet; anda swirler provided along the fuel nozzle body and extending into the central channel, the swirler having a helical vane wrapped circumferentially about the fuel nozzle centerline greater than or equal to π / 2 radians between a first end and a second end, axially opposing the first end.

2. The combustion section of claim 1, wherein the fuel nozzle comprises a fuel channel extending through the helical vane and having a fuel jet opening to a portion of the central channel downstream of the second end.

3. The combustion section of claim 2, wherein the fuel jet is located on the swirler.

4. The combustion section of claim 3, wherein the swirler comprises a protrusion that is a localized raised surface of an outer wall of the helical vane, with the fuel jet being located along a distal end of the protrusion.

5. The combustion section of claim 4, wherein the fuel nozzle comprises a fluid channel having a fluid jet located on the protrusion and opening to a portion of the central channel downstream of the swirler.

6. The combustion section of claim 5, wherein the fuel channel circumscribes the fluid channel within the protrusion.

7. The combustion section of claim 5, wherein the fuel channel emits a flow of gaseous fuel through the fuel jet, and the fluid channel emits one of a flow of liquid fuel, or a flow of steam through the fluid jet.

8. The combustion section of claim 1, wherein the helical vane is a plurality of helical vanes, each of the plurality of helical vanes terminating radially prior to the fuel nozzle centerline to form a gap between radially opposing portions of the plurality of helical vanes.

9. The combustion section of claim 8, wherein a hydraulic diameter of the gap is in a range from greater than or equal to 5% of a diameter of the swirler measured perpendicular to the fuel nozzle centerline and less than or equal to 20% of the diameter of the swirler measured perpendicular to the fuel nozzle centerline.

10. The combustion section of claim 1, wherein:the swirler generates a first flow of swirled air downstream of the second end;the swirler comprises a protrusion that is a localized raised surface of an outer wall of the helical vane, with the protrusion generating a second flow of swirled air downstream of the second end; andthe first flow of swirled air and the second flow of swirled air collectively form a cumulative flow of swirled air within the central channel, with the first flow of swirled air having a larger mass flow rate than the second flow of swirled air.

11. The combustion section of claim 1, wherein the helical vane is included in a plurality of helical vanes, with each helical vane of the plurality of helical vanes extending from a respective portion of the fuel nozzle body.

12. The combustion section of claim 11, wherein the swirler comprises a vane hub located within the central channel, with each helical vane of the plurality of helical vanes extending radially between the vane hub and the respective portion of the fuel nozzle body.

13. The combustion section of claim 1, wherein the fuel nozzle body comprises an inner surface defining a perimeter of the central channel; andthe fuel nozzle further comprises a centerbody spaced radially inwardly from the inner surface and extending through a respective portion of the central channel.

14. The combustion section of claim 13, wherein the helical vane extends outwardly from the centerbody.

15. The combustion section of claim 14, wherein the helical vane is included in a plurality of helical vanes, the plurality of helical vanes having a set of first helical vanes extending outwardly from the centerbody, and a set of second helical vanes extending inwardly from the inner surface.

16. The combustion section of claim 13, wherein the centerbody further comprises a set of centerbody fluid jets opening to a portion of the central channel downstream of the swirler.

17. The combustion section of claim 1, wherein:the wall includes a bluff area defined as a surface area of the wall confronting the combustion chamber;the fuel nozzle having a flow area defined as a surface area of the fuel nozzle outlet; anda ratio between the bluff area and the flow area is greater than or equal to 0.01 and less than or equal to 10.

18. The combustion section of claim 1, wherein the fuel nozzle is configured to feed a fuel air mixture to the combustion chamber, the fuel air mixture having a fuel to air ratio of greater than or equal to 0.005 and less than or equal to 0.060.

19. The combustion section of claim 1, wherein:the fuel nozzle comprises an axially forwardmost fuel jet configured to inject a flow of fuel into the central channel;a mixing length is defined as an axial distance with respect to the fuel nozzle centerline between the axially forwardmost fuel jet and the fuel nozzle outlet;the fuel nozzle outlet defines a hydraulic exit diameter; anda ratio of the mixing length to the hydraulic exit diameter is greater than or equal to 0 and less than or equal to 200.

20. The combustion section of claim 1, wherein:the fuel nozzle comprises a fuel channel opening to the central channel at a fuel jet; andthe fuel channel is configured to feed a flow of hydrogen-containing fuel to the central channel.

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