Engine fuel nozzle and swirler

Abstract

Turbine engines can utilize a combustor to combust fuel to drive a turbine that drives the engine. A fuel nozzle assembly can supply fuel to the combustor for combustion or ignition of the fuel. The fuel nozzle assembly can include a swirler and a fuel nozzle to supply a mixture of fuel and air for combustion. Increased efficiency and carbon-containing emissions requirements benefit from the use of alternative fuels that combust at higher temperatures than traditional fuels, requiring improved fuel introduction without flame holding or backfiring.

Description

[0001] This application is a divisional application of the invention patent application filed on August 31, 2022, with application number 202211055026.7 and invention title "Engine Fuel Nozzle and Swirler". Cross-references to related applications

[0002] This application claims priority and benefit to U.S. Provisional Patent Application No. 63 / 294,593, filed December 29, 2021, and U.S. Patent Application No. 17 / 691,781, filed March 10, 2022, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This topic generally relates to engine components having one or both of a fuel nozzle and a swirler located within the engine. Background Technology

[0004] Engines, such as turbine engines, include a turbine that is driven by the combustion of combustible fuel within the engine's combustor. Engines utilize fuel nozzles to inject combustible fuel into the combustor. Swirlers provide a mixture of fuel and air for efficient combustion. Attached Figure Description

[0005] In the description with reference to the accompanying drawings, a complete and implementable disclosure, including its best mode, is set forth for those skilled in the art, wherein:

[0006] Figure 1 This is a schematic cross-sectional view of an engine according to an exemplary embodiment of the present disclosure.

[0007] Figure 2 It is an exemplary embodiment of the present disclosure and Figure 1 A cross-sectional view of the fuel nozzle and cyclone separator used in the engine.

[0008] Figure 3 It includes a set of openings according to an exemplary embodiment of the present disclosure. Figure 2 An enlarged perspective view of the cross-section of the fuel nozzle.

[0009] Figure 4 This is based on exemplary embodiments of the present disclosure. Figure 2 and 3 An enlarged cross-sectional view of the fuel nozzle outlet.

[0010] Figure 5 It is an exemplary embodiment of the present disclosure for use Figure 1 The cross-section of the engine's alternative fuel nozzle and cyclone separator.

[0011] Figure 6 It is a cross-section of an alternative outlet for a fuel nozzle according to an exemplary embodiment of the present disclosure.

[0012] Figure 7 It is a cross-section of an alternative outlet for a fuel nozzle according to an exemplary embodiment of the present disclosure.

[0013] Figure 8 This is a cross-section of another alternative outlet for a fuel nozzle according to an exemplary embodiment of the present disclosure.

[0014] Figure 9 It is a cross-section of an alternative convex shape for a fuel nozzle according to an exemplary embodiment of the present disclosure.

[0015] Figure 10 It is a cross-section of an alternative concave shape for a fuel nozzle according to an exemplary embodiment of the present disclosure.

[0016] Figure 11-23 A graph illustrating a non-limiting exemplary embodiment of an embodiment of the present disclosure, showing the amount or rate of change of the swirl provided by the fuel nozzle assembly. Detailed Implementation

[0017] The aspects disclosed herein relate to fuel nozzle and swirler structures located within engine components, and more specifically, to fuel nozzle structures configured for use with elevated combustion engine temperatures, such as those using hydrogen fuel. Hydrogen fuel eliminates carbon emissions, but presents challenges related to flame retention due to its higher flame velocity. Current combustors using this fuel or other high-temperature fuels involve durability risks due to flame retention on combustor components caused by flashback. For illustrative purposes, this disclosure is described in relation to turbine engines for aircraft with combustors that drive turbines. However, it will be understood that the aspects disclosed herein are not limited to this and can have general applicability within engines, including but not limited to turbojet engines, turboprop engines, turboshaft engines, and turbofan engines. The aspects of the disclosure discussed herein can also have general applicability within non-aircraft engines with combustors, such as other mobile applications and non-mobile industrial, commercial, and residential applications.

[0018] Reference will now be made in detail to fuel nozzle and swirler architectures, one or more examples of which are shown in the accompanying drawings. Detailed descriptions use numbers and letters to refer to features in the drawings. Similar or analogous reference numerals in the drawings and description have been used to refer to similar or analogous portions of this disclosure.

[0019] The term "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 superior or better than other implementations. Furthermore, unless explicitly stated otherwise, all embodiments described herein should be considered exemplary.

[0020] The terms "front" and "rear" refer to relative positions within a turbine engine or carrier, and to the normal operating posture of the turbine engine or carrier. For example, in the context of a turbine engine, "front" refers to the position closer to the engine inlet, and "rear" refers to the position closer to the engine nozzle or exhaust port.

[0021] As used herein, the term "upstream" refers to the direction opposite to the direction of fluid flow, while the term "downstream" refers to the direction in the same direction as the fluid flow. The terms "forward" or "front" indicate what is in front of something, and "backward" or "rear" indicate what is behind something. For example, when used in relation to fluid flow, forward / front can indicate upstream, and backward / rear can indicate downstream.

[0022] The term "fluid" can refer to either a gas or a liquid. The term "fluid connectivity" means that fluids can establish connections between specified areas.

[0023] The terms "front" and "rear" refer to relative positions within a turbine engine or carrier, and to the normal operating posture of the turbine engine or carrier. For example, in the context of a turbine engine, "front" refers to the position closer to the engine inlet, and "rear" refers to the position closer to the engine nozzle or exhaust port.

[0024] The term “flame sustaining” refers to a state of continuous combustion of fuel such that the flame is sustained along or near the component, and typically along or near a portion of the fuel nozzle assembly as described herein, and the term “backfire” refers to the retreat of the combustion flame in the upstream direction.

[0025] Furthermore, as used herein, the term "radial" or "radially" refers to a direction away from a common center. For example, in the overall context of a turbine engine, radial refers to the direction along a ray extending between the engine's central longitudinal axis and the engine's outer perimeter.

[0026] All directional references (e.g., radial, axial, proximal, distal, up, down, upward, downward, left, right, lateral, front, back, top, bottom, above, below, vertical, horizontal, clockwise, counterclockwise, upstream, downstream, front, rear, etc.) are used for identification purposes only to aid the reader in understanding this disclosure and do not create limitation, particularly regarding the location, orientation, or use of aspects of the disclosure described herein. Connecting references (e.g., attachment, connection, joint, and engagement) are to be interpreted broadly and may include intermediate structural elements between sets of elements and relative movement between elements, unless otherwise indicated. Therefore, a connecting reference does not necessarily mean that two elements are directly connected and fixed relative to each other. Exemplary figures are for illustrative purposes only, and the dimensions, positions, order, and relative sizes reflected in the accompanying figures may vary.

[0027] The singular forms “a,” “an,” and “the” include plural references unless the context clearly indicates otherwise. Furthermore, as used herein, the term “group” or “set” of elements can be any number of elements, including only one.

[0028] As used herein and throughout the specification and claims, approximate language is applied to modify any quantitative representation that may allow for variation without altering its associated essential function. Therefore, values ​​modified by one or more terms such as “about,” “approximately,” “substantially,” and “basically” are not limited to specified precise values. In at least some cases, approximate language may correspond to the precision of the instrument used to measure the value, or the precision of the method or machine used to construct or manufacture the component and / or system. For example, approximate language may refer to a margin of 1%, 2%, 4%, 5%, 10%, 15%, or 20% of the endpoints of a single value, a range of values, and / or a range of defined values. Scope limitations are combined and interchanged herein and throughout the specification and claims; such scope is identified and includes all subscopes contained herein, unless otherwise indicated by context or language. For example, all scopes disclosed herein include endpoints, and endpoints can be combined independently of each other.

[0029] In some exemplary embodiments of this disclosure, a turbine engine is provided that defines a centerline and a circumferential direction. The turbine engine generally includes a turbine and a rotor assembly. The rotor assembly may be driven by the turbine. The turbine, rotor assembly, or both may define a substantially annular flow path relative to the centerline of the turbine engine. The turbine engine includes a combustor located upstream of the turbine, the combustor being configured to drive the turbine.

[0030] The burner introduces fuel from a fuel nozzle, mixes it with air supplied by a cyclone separator, and then burns it within the burner to drive the turbine. Increased efficiency and reduced emissions have driven the demand for using fuels that burn more cleanly or at higher temperatures, such as hydrogen. There is a need to improve burner durability under these operating parameters, such as improving flame control to prevent the flame from remaining on the fuel nozzle and cyclone separator components.

[0031] Figure 1 This is a schematic diagram of a turbine engine 10. As a non-limiting example, the turbine engine 10 can be used within an aircraft. The turbine engine 10 may include at least a compressor section 12, a combustion section 14, and a turbine section 16. A drive shaft 18 rotatably connects the compressor section 12 and the turbine section 16 such that rotation of one affects rotation of the other, and defines the rotation axis 20 of the turbine engine 10.

[0032] Compressor section 12 may include a low-pressure (LP) compressor 22 and a high-pressure (HP) compressor 24 fluidly connected in series with each other. Turbine section 16 may include an LP turbine 28 and an HP turbine 26 fluidly connected in series with each other. Drive shaft 18 may operatively connect the LP compressor 22, HP compressor 24, LP turbine 28, and HP turbine 26 together. Alternatively, drive shaft 18 may include an LP drive shaft (not shown) and an HP drive shaft (not shown). The LP drive shaft may connect the LP compressor 22 to the LP turbine 28, and the HP drive shaft may connect the HP compressor 24 to the HP turbine 26. The LP spool may be defined as a combination of the LP compressor 22, LP turbine 28, and LP drive shaft, such that rotation of the LP turbine 28 may apply a driving force to the LP drive shaft, which in turn may rotate the LP compressor 22. The HP spool can be defined as a combination of an HP compressor 24, an HP turbine 26, and an HP drive shaft, such that the rotation of the HP turbine 26 can apply driving force to the HP drive shaft, which in turn can rotate the HP compressor 24.

[0033] Compressor section 12 may include multiple axially spaced stages. Each stage includes a set of circumferentially spaced rotating blades and a set of circumferentially spaced stationary blades. The compressor blades for a stage of compressor section 12 may be mounted to a disc, which is mounted to drive shaft 18. Each set of blades for a given stage may have its own disc. The blades of compressor section 12 may be mounted to a housing that may extend circumferentially around turbine engine 10. It should be understood that the representation of compressor section 12 is merely illustrative and any number of stages may be possible. Furthermore, it is contemplated that any other number of components may be present within compressor section 12.

[0034] Similar to compressor section 12, turbine section 16 may include multiple axially spaced stages, each stage having a set of circumferentially spaced rotating blades and a set of circumferentially spaced stationary blades. Turbine blades for one stage of turbine section 16 may be mounted to a disc, which is mounted to drive shaft 18. Each set of blades for a given stage may have its own disc. The blades of the turbine section may be circumferentially mounted to the housing. It should be noted that any number of blades, blades, and turbine stages can be present, as the illustrated turbine section is merely schematic. Furthermore, it is contemplated that any other number of components may be present within turbine section 16.

[0035] Combustion section 14 may be arranged in series between compressor section 12 and turbine section 16. Combustion section 14 may be fluidly coupled to at least a portion of compressor section 12 and turbine section 16, such that combustion section 14 at least partially fluidly couples compressor section 12 to turbine section 16. As a non-limiting example, combustion section 14 may be fluidly coupled to HP compressor 24 at its upstream end and to HP turbine 26 at its downstream end.

[0036] During operation of the turbine engine 10, ambient air or atmospheric air is drawn into the compressor section 12 via a fan (not shown) upstream of the compressor section 12, where it is compressed to define pressurized air. This pressurized air can then flow into the combustion section 14, where it mixes with fuel and is ignited to generate combustion gases. The HP turbine 26 extracts some work from these combustion gases, driving the HP compressor 24. The combustion gases are discharged into the LP turbine 28, which extracts additional work to drive the LP compressor 22, and the exhaust gas is ultimately discharged from the turbine engine 10 via an exhaust section (not shown) downstream of the turbine section 16. The drive of the LP turbine 28 drives the LP spool to rotate the fan (not shown) and the LP compressor 22. The pressurized airflow and combustion gases together define the working airflow flowing through the fan, compressor section 12, combustion section 14, and turbine section 16 of the turbine engine 10.

[0037] Figure 2A fuel nozzle assembly 100 is shown, comprising a fuel nozzle 102 and a swirler 104 arranged annularly around the fuel nozzle 102. A dome (not shown) may be disposed in front of and adjacent to the swirler 104. The fuel nozzle 102 includes a nozzle supply passage 106, a fuel nozzle cap 108, and a nozzle outlet 110. The nozzle cap 108 may include a set of openings 140 allowing fuel to be discharged from the nozzle supply passage 106. The swirler 104 includes a swirler supply passage 120 that at least partially surrounds the fuel nozzle 102 and discharges to a flared cone 122. A set of swirler blades 124 are disposed within the swirler supply passage 120 to impart tangential or helical swirls to the air supplied by the swirler 104. Separator 126 extends from cyclone impeller 124 to split the airflow within cyclone supply passage 120 into two swirling airflows contained within an outer diameter passage 128 and an inner diameter passage 130 defined by separator 126. Separator 126 extends axially to a downstream end 132, such that the downstream end 132 connects to fuel nozzle supply passage 106 or Figure 1 The rotation axis 20 is coaxial, and it is anticipated that the downstream end 132 will have an angular deviation relative to the fuel nozzle supply channel 106, or relative to the longitudinal axis 112 defined by the fuel nozzle 102, the swirler 104, or the longitudinal axis defined by the combustion section 14 containing the fuel nozzle assembly 100. This deviation can be used to impart directionality to the burning fuel relative to the longitudinal range of the fuel nozzle 102. Additionally, the fuel nozzle 102 may be cylindrical, such that the radial axis 114 can be defined perpendicular to the longitudinal axis 112.

[0038] Go to Figure 3A portion of a fuel nozzle 102 is shown, including a set of openings 140 disposed in a fuel nozzle cover 108. For example, the openings 140 may be arranged in multiple circumferential rows of openings 142a-e, which are circumferentially defined relative to the axial extent or longitudinal axis 112 of the fuel nozzle supply passage 106, while suitable alternative arrangements are contemplated. Each opening 140 may include a tangential component having a centerline 138 arranged at a tangential angle 150, such that a swirling or helical component is applied to the fuel supplied through the fuel nozzle cover 108. The tangential angle 150 may be defined relative to the longitudinal axis 112, an axis parallel to the longitudinal axis 112, or a radius extending from the longitudinal axis 112. Furthermore, the tangential angle 150 of each opening 140 or each row of openings 142a-e may be specified. More specifically, the tangential component of the opening 140 or a row of openings 142e near the outer diameter of the fuel nozzle cap 108 can provide increased swirling relative to the opening 140 or the multiple rows of openings 142a-d within the outer diameter row of openings 140e, but by utilizing an increased tangential angle 150. For example, the tangential angle 150 of the opening 140 can be increased in a direction extending radially outward from the longitudinal axis 112. More specifically, the tangential angle 150 of each row of openings 142a-d can be increased as the multiple rows of openings 142a-d are positioned away from the longitudinal axis 112. In another non-limiting example, there may also be no tangential component relative to the center of the fuel nozzle cap 108 or the central opening 142a, such as coaxial with the fuel nozzle supply channel 106, which can further push the central recirculation from the swirler rearward, which can further reduce or eliminate flame retention or backfire. In an example where the openings are not arranged in a row, the tangential angle of each opening can be increased in a direction extending radially outward from the center of the fuel nozzle cap 108, such that openings farther from the longitudinal axis 112 have a larger tangential angle 150 than openings closer to the longitudinal axis 112. In another non-limiting example, the opening 140 closer to the center of the fuel nozzle cap 108 can be smaller than the opening 140 closer to the outer diameter of the fuel nozzle cap 108, such as having a smaller cross-sectional area, which can provide a reduction or elimination of jet flapping. In a non-limiting example, different cross-sectional profiles of the opening 140 are further contemplated, such as circular, slotted, oval, elliptical, or racetrack-shaped. It is further contemplated that the shape can vary based on its radial relationship with the center of the fuel nozzle cap 108, such that the shape varies based on radial position.

[0039] Go to Figure 4A fuel nozzle lip 144 is disposed at the nozzle outlet 110, downstream of the fuel nozzle cap 108. The fuel nozzle lip 144 includes an axial portion 146 and a tapering portion 148 extending from the axial portion 146. The axial portion 146 defines a constant cross-sectional area downstream of the fuel nozzle cap 108 and may be coaxial with the fuel nozzle 102. The tapering portion 148 defines an increasing or expanding cross-sectional area. In an alternative example, the nozzle outlet 110 may be formed as tapering, expanding, constant, or any combination thereof, which may be defined by a linear, curved, or discrete wall geometry or a combination thereof defining the nozzle outlet 110. The rounded tips of the fuel nozzle lip 144 provide reduced flow recirculation at the end of the nozzle outlet 110, which can eliminate stagnation points and flame retention.

[0040] refer to Figure 2-4 In operation, air is supplied via cyclone separator 104, and fuel is supplied via fuel nozzle supply passage 106. The air supply supplied via cyclone separator 104 is given a tangential, swirling, or helical component by cyclone separator blades 124 and is split into two streams by separator 126. These streams are formed as an inner diameter stream and an outer diameter stream relative to the radius extending from the longitudinal axis 112 of fuel nozzle supply passage 106. The two streams separated by separator 126 can swirl in the same direction to minimize any shear force between the inner and outer diameter streams, while anticipating countercurrents, where increased mixing or turbulence can be advantageous.

[0041] Similarly, fuel supplied from fuel nozzle 102 is provided with a tangential or swirling component via a set of openings 140 in fuel nozzle cap 108. The direction of the swirling flow provided by fuel nozzle 102 can be the same as the direction of the air supplied by swirler 104 to reduce or avoid any shear forces confined between fuel and air, while anti-flow is anticipated to increase the fuel-air mixture. In one example, the tangential component of opening 140 can be related to the tangential component provided by swirler 104. For example, the tangential angles of the two can be complementary to further reduce shear forces in the different flows. Alternatively, anti-flow is anticipated, where increased mixing between air and fuel can be expected. Axial portion 146 provides improved consistency for the velocity profile to maintain high axial velocities, which can prevent flame persistence at fuel nozzle outlet 110. As fuel is discharged from nozzle outlet 110, the expanding portion 148 at fuel nozzle lip 144 allows the fuel flow to expand, which reduces or eliminates the low-velocity region on nozzle lip 144, which reduces or eliminates flame retention on fuel nozzle 102 or swirler 104 hardware.

[0042] The co-swirling flow between the fuel and air streams reduces or eliminates high shear forces between the streams. This reduction in shear forces reduces the shear layer deficiency between the airflow and fuel stream. This reduction in deficiency allows for an improved distribution of the radial velocity profile, which in turn provides the ability to maintain high axial velocities for both fuel and airflow. High axial velocities reduce or eliminate flame retention and flashback at the fuel nozzle assembly 100, allowing the use of higher-temperature fuels, such as hydrogen, which can reduce or eliminate carbon emissions. Furthermore, the co-swirling flow of air and fuel prevents mixing, providing better mixing control and further reducing or eliminating flashback and flame retention during high-temperature operation.

[0043] Before the airflow is introduced into the fuel flow, the separator 126 provides an improved velocity distribution and its control. This improved velocity distribution helps prevent flame hold-up on the fuel nozzle 102, swirler 104, or flare cone 122. The constant area of ​​the separator 126, coaxial with the fuel nozzle supply passage 106, provides improved flow development for the swirling airflow, reducing or eliminating the occurrence of low-velocity regions generated by the separator 126. Fuel is introduced downstream of the swirler 104 to prevent flame hold-up on the swirler 104. Similarly, the swirling flow generated by the tangential opening 140 on the fuel nozzle cap 108 can reduce or avoid low velocities on the outer diameter of the fuel nozzle, which can reduce the chance of flame hold-up or backfire on the fuel nozzle 102.

[0044] Fuel nozzle lip 144 is positioned downstream of fuel nozzle cap 108 to reduce air-fuel mixing prior to fuel nozzle lip 144 and further reduce the formation of a recirculation zone in the area where the air and fuel flow mixes. Fuel nozzle cap 108 provides tangential swirl for fuel supply, while axial portion 146 and diffuser portion 148 provide a well-defined velocity profile for fuel supply before fuel is introduced from the air from swirler 104, while reducing or eliminating the recirculation zone.

[0045] The features described herein provide improved fuel supply to turbine engine combustors, which reduces or eliminates flame retention or backfire at the fuel nozzle assembly 100. This reduction or elimination allows for the use of higher-temperature fuels, such as hydrogen fuel, which provides improved or maintained efficiency while reducing or eliminating emissions.

[0046] Go to Figure 5An alternative fuel nozzle assembly 200 is provided. For example, the fuel nozzle assembly 200 includes a central channel 202 disposed within a fuel supply passage 204 and may be coaxial with each other. Thus, the fuel nozzle assembly 200 includes three supply lines: an external supply 206 provided by a cyclone separator 208, a fuel supply 210 provided by the fuel supply passage 204, and a central supply 212 provided by the central channel 202. In one example, air may be supplied within the central channel 202, while other fluids or materials, such as fuel, fuel mixtures, or diluents, are anticipated. In another non-limiting example, the fluid within the central channel 202 may have a swirling or helical component, such as that provided by a cyclone separator or impeller, or may be configured as non-swirling or laminar flow.

[0047] Additionally, each of the central supply 212 and the external supply 206 can be either swirling or non-swirling. In one example, all three supplies 206, 210, and 212 can be supplied with swirling components in the same direction to reduce shear forces between the different flows. Alternatively, only the central channel 202 can be non-swirling, which can provide a way to move any recirculation zone behind or downstream of the end of the fuel supply channel 204, which can reduce or eliminate flame hold-up and backfire. In another example, fuel supplied from fuel supply 210 can be positioned between the external swirling air in the external supply 206 and the internal non-swirling air in the central channel 202, providing improved fuel and air mixing downstream of the fuel supply channel 204. In yet another example, the central channel 202 can be used as a pilot or for introducing other materials, such as a diluent for suppressing nitrogen oxides, in a non-limiting example. It should be understood that the different use of swirling or non-swirling airflows can be used to define the velocity profile of the fuel and air supplied, which can be used to reduce or eliminate flame hold-up or backfire at the fuel nozzle assembly 200, allowing the use of higher temperature fuels, such as hydrogen.

[0048] In another non-limiting example, the outlet of the center channel 202 may be cut off at the fuel nozzle cap 108, at the fuel nozzle lip 144, or between the fuel nozzle cap 108 and the lip 144. It is also possible that the center channel 202 may extend behind the fuel nozzle lip 144. The channel of the center channel 202 may be tapered, of constant area, or tapered to control the velocity profile at the outlet of the center channel 202. If the center channel 202 is used as a pilot or diluent injection, the flow through the circuit can be controlled independently for different operating cycles. The outlet of the fuel nozzle lip 144 may also feature a constant area section followed by a tapered section. It is contemplated that the center channel 202 may have a nozzle cap with axial or tangential orifices, after which the fuel nozzle lip is positioned. For example, instead of an orifice, the central channel 202 may have a cyclone separator, such as a cyclone impeller, with a low swirl number ranging from 0 to 0.5.

[0049] The radial placement of separator 216 controls the flow area and velocity at the cyclone channel outlet before the airflow interacts with the fuel flow. The radial position of separator 216 can range from 20% to 80% of the channel height H, which can be defined as the radial distance between the fuel nozzle 218 and the outer wall 214 of the cyclone. In one example, separator 216 can be positioned from 0.2H to 5H, while other or larger ranges are anticipated. Sufficient length is provided between the rear end of separator 216 and the rear tip 220 of the fuel nozzle such that the wake generated by separator 216 is reduced or eliminated before the airflow interacts with the fuel flow. The rear end of separator 216 can have sharp vertical or radial cuts, slots, or grooves to minimize the separator wake, or it can include rounded corners to minimize the wake from separator 216.

[0050] Go to Figure 6 An alternative nozzle tip 252 for the fuel nozzle 250 is disposed downstream of the nozzle cap 254 and has a tapering geometry. The nozzle tip 252 may include a lip length L defined along the fuel nozzle 250 from the nozzle cap 254 to the distal end of the nozzle tip 252. The diameter D may be defined as the diameter of the fuel nozzle 250, increasing as the nozzle tip 252 tapers at the tapering portion 260. While the diameter D... Figure 6The view shown is cut off, but it should be understood that the fuel nozzle 250 can be annular or cylindrical, defining a diameter D. The opening diameter d can be defined as the diameter of the opening 256 disposed in the nozzle cap 254. In a non-limiting example, the ratio of the lip length L to the opening diameter d can be between zero and fifty (0-50), and the ratio of the lip length L to the nozzle diameter D can be between zero and five (0-5), while a wider range is anticipated. The outer surface 258 of the nozzle tip 252 can have a constant diameter to maintain high speeds on the outside of the fuel nozzle 250. In one example, for hydrogen fuel or a hydrogen fuel mixture, the fuel pressure ratio across the opening 256 can be from 1.0 to 1.4, while other pressure ratios are anticipated based on the specific fuel.

[0051] Go to Figure 7 An alternative nozzle tip 272 for the fuel nozzle 270 is disposed downstream of a separator 274, which is located within an outer vortex 276. The outer surface 278 of the nozzle tip 272 may be curved, defining a reduced thickness 280 of the rearwardly extending nozzle tip 272, defining a diverging portion 282 for a radially outer vortex passage 284. The diverging portion 282 may begin behind the separator 274 to create a velocity profile with a high axial velocity component for the air from the vortex 276 prior to the diverging portion 282. The diverging portion 282 can provide a reduction or elimination of recirculation zones or flame hold-up at the nozzle tip 272, as the inward curvature accelerates the airflow at the nozzle tip 272 to reduce or avoid flame hold-up at the nozzle tip 272.

[0052] Go to Figure 8 An alternative nozzle tip 292 for the fuel nozzle 290 is disposed downstream of the separator 294 and the nozzle cap 296 contained within the fuel nozzle 290. The nozzle tip 292 includes an inner surface 298 and an outer surface 300. The inner surface 298 and the outer surface 300 may be curved such that a diverging channel 302 is defined for the vortex generator 304, and a contracting channel 306 is defined for the fuel nozzle 290. The fuel nozzle 290 may include a circumferentially shaped tip portion 308 having a constant cross-sectional area, and it is contemplated that this portion is removed such that the fuel nozzle 290 terminates at a curved end of the inner surface 298. The tip portion 308 can provide improved velocity to eliminate flame hold-up, while eliminating the tip portion 308 can help reduce the recirculation zone at the nozzle tip 292.

[0053] Now go to Figure 9The alternative fuel nozzle 330 includes a nozzle cap 332 that protrudes relative to the fuel flow through the fuel nozzle 330. For example, the curvature of the nozzle cap 332 can be defined by a circular or elliptical profile, which can define a hemispherical or elliptical shape for the nozzle cap 332, while other geometries are contemplated. An opening 334 is disposed in the nozzle cap 332 and can be similar to the opening 140 described herein, having an increased swirling component closer to the outer diameter of the fuel nozzle 330. Furthermore, in addition to utilizing the tangential orientation of the opening 334 to impart swirling flow to the fuel passing through the nozzle cap 332, or in the absence of utilizing the tangential orientation of the opening 334 to impart swirling flow to the fuel passing through the nozzle cap 332, the centerline 336 of the opening 334 can be oriented toward the center of the hemisphere or ellipsoid, or can be axially aligned relative to the fuel nozzle 330. Thus, it should be understood that the opening 334 can be arranged axially, radially, tangentially, or in a combination of these angular arrangements.

[0054] Figure 10 Another alternative fuel nozzle 350 is shown, which includes a nozzle cap 352 recessed relative to the fuel flow through the fuel nozzle 350. Figure 9 Similarly, the curvature of the nozzle cap 352 can be hemispherical or elliptical, while other geometries are also anticipated. Additionally, the opening 354 can be oriented relative to the nozzle cap 352, such as being aligned with the center of a hemisphere or ellipse defined by the curvature of the nozzle cap 352, or being axially arranged relative to the fuel nozzle 350. Furthermore, the opening 354 can provide swirling flow to the fuel flow through the fuel nozzle 350, while it is contemplated that the opening 354 does not provide swirling flow. Figure 9 Similarly, it should be understood that the opening 354 can be arranged axially, radially, tangentially, or in combination of these angular arrangements.

[0055] Figure 11-23 A graphical representation of the swirl rate of the airflow supplied by the swirler on the x-axis is shown relative to the radial position on the y-axis. The centrally located dashed line demarcates the boundary between the fuel supply from the fuel nozzle and the air supply from the swirler radially outside the fuel nozzle. More specifically, the supplied swirl volume or swirl rate can be controlled based on the radial position, which can be defined by tangential openings in the swirler and fuel nozzle cap as described herein.

[0056] Figure 11 A graph 400 is shown, including an x-axis 402 representing the increasing rate of tangential swirl and a y-axis 404 representing the radial position, defined radially outward from the center of the fuel nozzle. The dashed line 406 indicates the radial transition from the fuel nozzle to the radially outer swirler.

[0057] As can be understood from graph 408, indicated at 410, the swirl volume in approximately 50% of the radial range from the center of the fuel nozzle to the fuel nozzle includes zero swirl. Indicated at 412, the swirl defined in the outer 50% radial range of the fuel nozzle can be increased at a rate sufficiently similar to the swirl rate at the radial interior of the swirler. Then, indicated at 412, the swirl rate of the swirler can be further increased at a higher rate than the swirl at the fuel nozzle at 410, extending radially outward. Although the 50% transition between the axial and tangential directions of the fuel is mentioned above, this transition can occur at any radial location at the tip of the fuel nozzle.

[0058] The absence of swirl within the radial center of the fuel nozzle provides for the positioning of recirculated foam in the rearward direction, which can be due to the recirculated fuel flow caused by the fuel-generated wake, thus reducing flame hold at the fuel nozzle. Increasing the fuel swirl rate from no swirl to matching the swirl within the radial interior of the swirler reduces shear forces between the two flows and eliminates flame hold. Finally, increasing tangential swirl in the radially outward direction within the swirler reduces flame hold at the flared cone.

[0059] It should be understood that the numbering, size, orientation, and placement of the openings in the fuel nozzle can be varied to achieve a desired velocity distribution at the fuel nozzle exit. Furthermore, the size of the openings can be varied to alter the fuel momentum profile at the nozzle exit. This velocity distribution and momentum profile can be tailored for a specific fuel nozzle assembly or engine to reduce recirculation, flame hold-up, or backfire.

[0060] refer to Figure 12 Another graph, 420, shows the constant increase in the swirl rate of the fuel supply, indicated at 422, where the rate is zero at the center. The swirl rate at the point where the fuel meets the air from the swirler, indicated at 424, can be similar to reduce the shear force between the two flows.

[0061] Figure 13 Another graph, 430, shows zero swirl at the fuel nozzle, indicated at 432. The swirl rate at the radially inward vortex can be zero, matching the swirl rate at the fuel nozzle, and then, as indicated at 434, increases with a constant rate extending radially outward. The absence of swirl at the fuel nozzle and radially inward provides reduced shear between the two flows while increasing the fuel velocity component. Additionally, the higher swirling part at the radially outward vortex prevents flame retention at the flare cone.

[0062] Figure 14 Showing Figure 13An alternative arrangement of curve 430 is depicted as curve 440, in which zero swirl extends into the hydrocyclone such that the hydrocyclone includes no swirl in the radially inner portion indicated at 442, and a swirl profile in the radially outer portion indicated at 444, which can be allowed by a separator as described herein to split the hydrocyclone into two streams.

[0063] Figure 15 Another alternative curve 450 is shown, where, as indicated at 452, the center of the fuel nozzle includes zero swirl. As indicated at 454, the swirl in the radially outer portion of the fuel nozzle can be increased, extending radially outward. As indicated at 456, the swirl in the radially inner portion of the swirler can be the same as the radially outer swirl from the fuel nozzle to reduce shear between the two flows. Then, as indicated at 458, the swirl can be reduced to zero. The zero flow at the fuel center pushes back the recirculating foam, while the zero swirl in the radially outer portion can increase the velocity profile along the flared cone, which can reduce flame hold-up. This type of distribution is for geometries with lower flared cone angles or no cylindrical flare.

[0064] Figure 16 Another alternative curve, 462, shows a non-zero swirling flow at the center of the fuel nozzle, indicated at 460, which decreases radially outward to zero and remains zero for a portion before reaching the radially outer portion of the fuel nozzle. Then, indicated at 464, the swirler can include zero swirling flow in the radially inner portion to reduce shear between the two flows; the radially inner portion of the swirler includes zero swirling flow, while the increased swirling flow extends radially outward in the radially outer portion of the swirler. The increased swirling flow at the radially outer portion can provide reduced flame retention along the flare cone.

[0065] Now for reference Figure 17 This shows another alternative curve, 470, illustrating the non-zero swirl at the center of the fuel nozzle, indicated at 472, which decreases radially outward to zero swirl at the radially outer part of the fuel nozzle. Then, as indicated at 474, the swirler can include zero swirl at the radially inner part to reduce shear between the two flows, with the increased swirl extending radially outward. The increased swirl at the radially outer part can provide reduced flame retention along the flare cone.

[0066] Now for reference Figure 18 Another graph 480 indicates the common distribution profile between the fuel nozzle and the swirler, where at 482 and 486 it is indicated that each includes a radially inner portion with zero swirling. At 484 and 488 it is indicated that the radially outer portion of each of the fuel nozzle and the swirler may include increased swirling extending radially outward from zero.

[0067] Figure 19Another graph 490 is shown, with another common distribution profile between the fuel nozzle and the swirler, indicated at 492 and 494 respectively, each increasing radially outward from zero swirling.

[0068] Figure 20 Another graph 500 is shown. As indicated at 502, the fuel nozzle can have an increasing swirl radially outward from zero swirl at the center. The swirl in the cyclone separator can be constant and non-zero, which can be the same as the swirl at the radially outer part of the fuel nozzle to reduce shear force between the two flows.

[0069] Figure 21 Another graph 510 is shown, where, as indicated at 512, the fuel nozzle swirling flow increases from zero at a constant rate, extending radially outward. The swirling flow at the radially inner part of the swirler can be the same as the swirling flow at the radially outer part of the fuel nozzle, thus reducing the shear force between the two flows. Then, as indicated at 514, the swirling flow in the swirler can decrease to zero, extending radially outward.

[0070] Figure 22 Another graph 520 is shown, featuring a common profile of the fuel nozzle and the swirler. Indicated at 522 and 524 are non-zero swirlers, each included radially inward or at the center of the fuel nozzle, reduced to zero swirling. Then, indicated at 526 and 528 are portions that increase from zero to match the swirling at the radially inward location. This reduces the shear force between the fuel nozzle and the swirler while defining a variable profile to reduce or eliminate flame retention.

[0071] Figure 23 Another graph 540 is shown, where at 542 and 544 it is indicated that both the fuel nozzle and the swirler include constant non-zero swirling flow, which can reduce the shear force between the two flows.

[0072] It should be understood that, although Figure 11-23 The various contours are displayed as linear or constant. The non-constant rate of change of the swirling flow in the radial direction can be non-constant, causing the curve to bend, but combinations of constant and non-constant are also expected.

[0073] It should be further understood that altering the swirl rate of the fuel flow from the fuel nozzle and the air flow from the swirler can be used to develop complex velocity profiles that can be customized to reduce or eliminate flame holding, backfire, and recirculation at various radial locations of the fuel nozzle assembly. This can enable the use of fuels that burn faster or at higher temperatures, such as hydrogen or hydrogen mixtures.

[0074] Furthermore, it should be understood that the tangential angle of the fuel swirl or orifice should gradually increase to reduce or avoid flame on the fuel nozzle lip. The average swirl at the nozzle tip from the fuel circuit can range from 0 to 1.5, and the average swirl from the outlet of the swirler air circuit can also range from 0 to 1.5 before interacting with the fuel. Reducing the shear force between the swirler air circuit and the fuel nozzle provides a consistent velocity profile, which reduces flame retention on downstream hardware.

[0075] Furthermore, it is desirable that the tangential velocity of the fuel nozzle can be gradually increased to reduce sudden deficiencies in velocity, pressure, or flow conditions that lead to high shear layers downstream of the fuel nozzle in the fuel passage. Similarly, the airflow velocity must be well controlled to reduce flame retention on cyclone components such as separators, cyclone outer walls, cyclone inner walls, and flare cones.

[0076] It should be understood that the aspects and embodiments provided herein are not limited to those shown. More specifically, one or more aspects of an embodiment may be combined with, interchanged with, or removed from one or more other embodiments, such that those skilled in the art will anticipate further embodiments within the scope of this disclosure, although not explicitly shown.

[0077] This written description uses examples to disclose this disclosure, including best practices, and also enables any person skilled in the art to practice this disclosure, including making and using any apparatus or system and performing any incorporated methods. The patentable scope of this disclosure is defined by the claims, but may include other examples that would occur to a person skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that are not indistinguishable from the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims.

[0078] Further aspects are provided by the subject matter of the following clause: a turbine engine comprising: a compressor section, a combustor section, and a turbine section arranged in a series flow configuration, the combustor section including a fuel nozzle assembly comprising: a fuel nozzle defining a longitudinal axis and a radial axis orthogonal to the longitudinal axis, and the fuel nozzle including a fuel passage terminating at an outlet, the fuel nozzle including a nozzle tip; and a nozzle cap including a set of openings and disposed within the fuel passage; wherein at least one of the openings has a centerline oriented at a tangential angle relative to the radial axis.

[0079] The turbine engine according to any one of the foregoing clauses, wherein the set of openings is arranged in multiple rows circumferentially defined relative to the longitudinal axis.

[0080] In any of the preceding clauses, the tangential angle of the multiple rows of openings increases with increasing radial distance from the longitudinal axis in the turbine engine.

[0081] In any of the preceding clauses, the tangential angle of the opening at the center of the nozzle cover in the set of openings of the turbine engine is zero.

[0082] The turbine engine according to any one of the foregoing clauses further includes a nozzle lip portion defined between the nozzle cover and the nozzle tip.

[0083] The turbine engine according to any one of the foregoing clauses, wherein the nozzle lip includes an axial portion and a diffuser portion.

[0084] The turbine engine according to any one of the foregoing clauses, wherein the nozzle tip defines the lip length and the fuel nozzle defines the diameter, and the ratio of the lip length to the diameter is between zero and five.

[0085] The turbine engine according to any one of the foregoing clauses, wherein the nozzle tip defines a lip length and each of the set of openings defines an opening diameter, and the ratio of the lip length to the opening diameter is between zero and fifty.

[0086] The turbine engine according to any one of the foregoing clauses, wherein the injector lip includes a gradually expanding portion defined on the outer surface of the fuel nozzle.

[0087] The turbine engine according to any one of the foregoing clauses, wherein the injector lip further includes a tapered portion defined on the inner surface of the fuel nozzle.

[0088] In any of the preceding clauses, the turbine engine wherein the nozzle cover is bent into a concave or convex shape relative to the flow direction through the fuel passage.

[0089] The turbine engine according to any one of the foregoing clauses further includes a central channel that extends within the fuel passage and through the nozzle cover.

[0090] A fuel nozzle and swirler assembly for an engine, the fuel nozzle and swirler assembly comprising: a fuel nozzle defining a longitudinal axis and a radial axis orthogonal to the longitudinal axis; a swirler surrounding the fuel nozzle, the swirler including a set of blades to impart a tangential component tangential to the radial axis to fluid passing through the swirler; and a separator extending rearward from the set of blades to divide the swirler into a radially outer channel and a radially inner channel.

[0091] The fuel nozzle and cyclone assembly according to any one of the foregoing clauses, wherein the separator is arranged parallel to the fuel nozzle.

[0092] The fuel nozzle and swirler assembly according to any one of the foregoing clauses, wherein the radial outer channel and the radial inner channel are coaxial with the fuel nozzle.

[0093] The fuel nozzle and cyclone assembly according to any one of the foregoing clauses, wherein the fuel nozzle further includes a nozzle cap, a set of openings extending through the nozzle cap, at least some of the openings being arranged at a tangential angle relative to a radius defined relative to the longitudinal direction.

[0094] A method for supplying fuel and air to a combustor of a turbine engine, the method providing fuel supply via a fuel nozzle defining a longitudinal axis and air supply via a vortex surrounding the fuel nozzle, the method comprising: providing a tangential component tangential to the fuel supply with respect to a radius extending from the longitudinal axis, wherein a set of openings disposed in a nozzle cap are arranged at a tangential angle.

[0095] The method according to any one of the foregoing clauses, wherein the tangential component of the fuel supply is complementary to the swirling air supply provided by the swirler.

[0096] According to any one of the preceding clauses, the cyclone includes a separator that divides the air supply into an inward radial supply and an outward radial supply, and the tangential component of the fuel supply is complementary to the cyclone of the inward radial supply.

[0097] The method according to any one of the foregoing clauses, wherein the tangential component of the fuel supply is rotated in the opposite direction to the air supply provided by the cyclone.

Claims

1. A fuel nozzle and swirler assembly for an engine, characterized in that, The fuel nozzle and cyclone assembly includes: A fuel nozzle that defines a longitudinal axis and a radial axis orthogonal to the longitudinal axis; A cyclone separator surrounding the fuel nozzle to define a cyclone passage having a radial height H extending along the radial axis between the fuel nozzle and the cyclone separator, the cyclone separator including a set of blades to impart a tangential component tangential to the radial axis to the fluid passing through the cyclone separator; and A separator, extending rearward from the set of impellers, divides the cyclone into an outer diameter channel and an inner diameter channel. The outer diameter channel defines an outer portion extending from the separator to a radial height H of the cyclone, and the inner diameter channel defines an inner portion extending from the fuel nozzle to a radial height H of the separator. The radial position of the separator is 20% to 80% of the radial height H.

2. The fuel nozzle and cyclone assembly according to claim 1, characterized in that, The separator is arranged parallel to the fuel nozzle.

3. The fuel nozzle and cyclone assembly according to claim 1, characterized in that, The outer diameter channel and the inner diameter channel are coaxial with the fuel supply channel of the fuel nozzle.

4. The fuel nozzle and cyclone assembly according to claim 1, characterized in that, in, The fuel injector further includes an injector cap, the injector cap including a set of openings extending through the injector cap, at least some of the openings being arranged at a tangential angle relative to a radius defined relative to the longitudinal direction.

5. The fuel nozzle and swirler assembly according to claim 1, characterized in that, The fuel nozzle defines a fuel supply passage and a central passage coaxial with each other within the fuel supply passage.

6. The fuel nozzle and swirler assembly according to claim 5, characterized in that, The fuel nozzle is configured such that fluid flowing through the central channel swirls, and fluid flowing through the fuel supply channel also swirls.

7. The fuel nozzle and swirler assembly according to claim 5, characterized in that, The fuel nozzle is configured such that fluid passing through the central channel does not swirl, while fluid passing through the fuel supply channel does swirl.

8. The fuel nozzle and swirler assembly according to claim 1, characterized in that, The fuel nozzle includes a nozzle cap that defines a first set of openings and a second set of openings; the first set of openings and the second set of openings are arranged circumferentially relative to the longitudinal axis.

9. The fuel nozzle and swirler assembly according to claim 8, characterized in that, The first set of openings and the second set of openings are configured such that fluid flowing through the openings of the first set of openings swirls, while fluid flowing through the openings of the second set of openings does not swirl.

10. The fuel nozzle and swirler assembly according to claim 1, characterized in that, The cyclone separator includes a flared cone extending rearward from the set of blades.

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