US20160061452A1

US20160061452A1 - Corrugated cyclone mixer assembly to facilitate reduced nox emissions and improve operability in a combustor system

Info

Publication number: US20160061452A1
Application number: US14/469,029
Authority: US
Inventors: David James Walker; Joel Meier Haynes; Narendra Digamber Joshi; Junwoo Lim; Krishna Kumar Venkatesan; Sarah Marie Monahan
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 2014-08-26
Filing date: 2014-08-26
Publication date: 2016-03-03

Abstract

A corrugated cyclone mixer for use in a fuel injection assembly of a turbine engine. The corrugated cyclone mixer generally includes an annular housing including a flange portion and a lip portion configured downstream of the flange portion. The mixer further including a swirler disposed therein the annular housing for inducing a cyclonic motion in the corrugated cyclone mixer. The swirler is configured upstream of the flange portion and including a plurality of swirler vanes to produce a swirling air flow. The lip portion forming an outlet downstream of the swirler and including a plurality of corrugations at an aft end. The plurality of corrugations are configured to mix the swirling air flow and an injected fuel stream flowing therethrough the corrugated cyclone mixer. Additionally disclosed is a fuel injection assembly and a turbine assembly including the corrugated cyclone mixer.

Description

BACKGROUND

The embodiments described herein relate generally to combustion systems, and more specifically, to systems that facilitate optimal mixing of liquid and gaseous fuels with oxidizer in a turbine combustor, such as gas turbine engine or liquid fuel aero-engine.
Combustors are commonly used in industrial, power generation and aero operations to ignite fuel to produce combustion gases having a high temperature and pressure. For example, turbo-machines such as gas turbine engines or aero-engines, may include one or more combustors to generate power or thrust. A typical turbine system includes an inlet section, a compressor section, a combustion section, a turbine section, and an exhaust section. The inlet section cleans and conditions a working fluid (e.g., air) and supplies the working fluid to the compressor section. The compressor section increases the pressure of the working fluid and supplies a compressed working fluid to the combustion section. The combustion section mixes fuel with the compressed working fluid and ignites the mixture to generate combustion gases having a high temperature and pressure. The combustion gases flow to the turbine section where they expand to produce work. For example, expansion of the combustion gases in the turbine section may rotate a shaft connected to a generator to produce electricity.
The combustion section may include one or more combustors annularly arranged between the compressor section and the turbine section, and the temperature of the combustion gases directly influences the thermodynamic efficiency, design margins, and resulting emissions of the combustor. For example, higher combustion temperatures generally improve the thermodynamic efficiency of the combustor. However, higher combustion temperatures also promote flame holding conditions in which the combustion flame migrates towards the fuel being supplied by nozzles, possibly causing accelerated damage to the nozzles in a relatively short amount of time. In addition, higher combustion temperatures generally increase the disassociation rate of diatomic nitrogen, increasing the production of nitrogen oxides (NOx) for the same residence time in the combustor. Conversely, a lower combustion temperature associated with reduced fuel flow and/or part load operation (turndown) generally reduces the chemical reaction rates of the combustion gases, increasing the production of carbon monoxide and unburned hydrocarbons for the same residence time in the combustor.
In a particular combustor design, the combustor may include a cap assembly that extends radially across at least a portion of the combustor, and one or more fuel nozzles may be radially arranged across the cap assembly to supply fuel to the combustor. The combustor may also include at least one annular liner that extends downstream from the cap assembly. The liner at least partially defines a combustion chamber within the combustor. The liner further defines a hot gas path that extends between the combustion chamber and an inlet to the turbine. The fuel nozzles may include swirler vanes and/or other flow guides to enhance mixing between the fuel and the compressed working fluid to produce a lean fuel-air mixture for combustion. The swirling fuel-air mixture flows into the combustion chamber where it ignites to generate the hot combustion gases. The hot combustion gases are routed through the hot gas path to the inlet of the turbine.
Although generally effective at enabling higher operating temperatures, the overall effectiveness of the engine is at least partially dependent upon how well the fuel-air combination that flows from the injector mixes with the swirling fuel-air mixture in the combustion chamber and/or with the hot combustion gases flowing through the liner generally downstream from the combustion chamber. In general, increased levels of premixing tend to increase autoignition risk and increase dynamics. In addition, mixing of fuel and air in a high temperature environment is very challenging because the fuel/air mixture can preignite/autoignite in the fuel nozzle and damage the hardware.
Attempts at increasing fuel air mixing in the fuel nozzle have come in various forms including number of fuel orifices, orifice diameter, mixer geometry, and axial placement of fuel orifices.
As a result, an improved mixing apparatus for supplying fuel to a combustor that enhances mixing of the fuel-air combination that flows from the fuel injectors would be useful.

BRIEF DESCRIPTION OF THE DISCLOSURE

Aspects and advantages of the disclosure are set forth below in the following description, or may be obvious from the description, or may be learned through practice of the disclosure.
In one aspect, corrugated cyclone mixer assembly for use in a fuel injection assembly of a turbine engine is provided. The corrugated cyclone mixer assembly includes an annular housing, a swirler. The annular housing comprises a flange portion and a lip portion configured downstream of the flange portion. The swirler is disposed therein the annular housing for inducing a cyclonic motion in the corrugated cyclone mixer assembly. The swirler is configured upstream of the flange portion and includes a plurality of swirler vanes to produce a swirling air flow. The lip portion forms an outlet downstream of the swirler and includes a plurality of corrugations at an aft end. The plurality of corrugations are configured to mix the swirling air flow and an injected fuel.
In another aspect, a fuel injection assembly for use in a combustion chamber of a turbine engine assembly is provided. The fuel injection assembly including a fuel nozzle including a main housing and defining an annular cavity and a corrugated cyclone mixer disposed about the fuel nozzle. The fuel nozzle including a fuel manifold and a plurality of fuel injection ports. The fuel manifold is in fluid communication with a source of fuel. Each of the plurality of fuel injection ports is configured to introduce a fuel column into the annular cavity. The corrugated cyclone mixer assembly includes an annular housing and a swirler disposed therein the annular housing for inducing a cyclonic motion in the corrugated cyclone mixer assembly. The annular housing comprising a flange portion and a lip portion configured downstream of the flange portion. The swirler is configured upstream of the flange portion and includes a plurality of swirler vanes to produce a swirling air flow. The lip portion forms an outlet downstream of the swirler and includes a plurality of corrugations at an aft end. The plurality of corrugations are configured to mix the swirling air flow and an injected fuel stream flowing therethrough the corrugated cyclone mixer assembly.
In yet another aspect, a turbine engine assembly is provided. The turbine engine assembly including a compressor section, a combustor section and a turbine section configured in a downstream axial flow relationship. The combustor section including a combustion chamber and a fuel injection assembly disposed in the combustion chamber. The fuel injection assembly including a fuel nozzle including a main housing and defining an annular cavity and a corrugated cyclone mixer assembly disposed about the fuel nozzle. The fuel nozzle including a fuel manifold in fluid communication with a source of fuel and a plurality of fuel injection ports. Each fuel injection port is configured to introduce a fuel column into the annular cavity. The corrugated cyclone mixer assembly including an annular housing and a swirler disposed therein the annular housing for inducing a cyclonic motion in the corrugated cyclone mixer assembly. The annular housing comprising a flange portion and a lip portion configured downstream of the flange portion. The swirler is configured upstream of the flange portion and including a plurality of swirler vanes to produce a swirling air flow. The lip portion forms an outlet downstream of the swirler and includes a plurality of corrugations at an aft end. The plurality of corrugations are configured to mix the swirling air flow and an injected fuel stream flowing therethrough the corrugated cyclone mixer assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present disclosure, including the best mode thereof to one skilled in the art, is set forth more particularly in the remainder of the specification, including reference to the accompanying figures, in which:

FIG. 1 is schematic diagram of an exemplary turbine engine assembly including a combustion section, according to one or more embodiments disclosed herein;

FIG. 2 is a simplified side cross-section view of a portion of an exemplary combustor, according to one or more embodiments disclosed herein;

FIG. 3 is a simplified side cross-section view of a fuel injection assembly including a corrugated cyclone mixer assembly, according to one or more embodiments disclosed herein;

FIG. 4 is an enlarged simplified diagram illustrating a portion of the corrugated cyclone mixer assembly for use in the fuel injection assembly of FIG. 3, according to one or more embodiments disclosed herein;

FIG. 5 is an enlarged simplified isometric view illustrating a portion of the corrugated cyclone mixer assembly of FIG. 3, according to one or more embodiments disclosed herein;

FIG. 6 is an enlarged simplified isometric view of an alternate embodiment of a portion of a corrugated cyclone mixer assembly for use in the fuel injection assembly of FIG. 3, according to one or more embodiments disclosed herein;

FIG. 7 is an enlarged simplified side view of an alternate embodiment of a portion of a corrugated cyclone mixer assembly for use in the fuel injection assembly of FIG. 3, according to one or more embodiments disclosed herein;

FIG. 8 is an enlarged simplified side view of an alternate embodiment of a portion of a corrugated cyclone mixer assembly for use in the fuel injection assembly of FIG. 3, according to one or more embodiments disclosed herein;

FIG. 9 is an enlarged simplified isometric view of an alternate embodiment of a portion of a corrugated cyclone mixer assembly for use in the fuel injection assembly of FIG. 3, according to one or more embodiments disclosed herein; and

FIG. 10 is an enlarged simplified isometric view of an alternate embodiment of a portion of a corrugated cyclone mixer assembly for use in the fuel injection assembly of FIG. 3, according to one or more embodiments disclosed herein.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION OF THE DISCLOSURE

The exemplary methods and systems described herein overcome the structural disadvantages of known fuel injectors by providing optimal mixing of liquid and gaseous fuels with oxidizer in the combustor. It should also be appreciated that the term “first end” is used throughout this application to refer to directions and orientations located upstream in an overall axial flow direction of fluids with respect to a center longitudinal axis of a combustion chamber. It should be appreciated that the terms “axial” and “axially” are used throughout this application to refer to directions and orientations extending substantially parallel to a center longitudinal axis of a combustion chamber. It should also be appreciated that the terms “radial” and “radially” are used throughout this application to refer to directions and orientations extending substantially perpendicular to a center longitudinal axis of the combustion chamber. It should also be appreciated that the terms “upstream” and “downstream” are used throughout this application to refer to directions and orientations located in an overall axial flow direction with respect to the center longitudinal axis of the combustion chamber.
Each example is provided by way of explanation of the disclosure, not limitation of the disclosure. In fact, it will be apparent to those skilled in the art that modifications and variations can be made in the present disclosure without departing from the scope or spirit thereof. For instance, features illustrated or described as part of one embodiment may be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present disclosure covers such modifications and variations as come within the scope of the appended claims and their equivalents. Although exemplary embodiments of the present disclosure will be described generally in the context of a mixer assembly for a combustor incorporated into a gas turbine for purposes of illustration, one of ordinary skill in the art will readily appreciate that embodiments of the present disclosure may be applied to any combustor assembly incorporated into any turbomachine, and not limited to gas turbine engines.
Referring now to the drawings, wherein identical numerals indicate the same elements throughout the figures, FIG. 1 provides a diagram of an exemplary turbine engine assembly 10 that may incorporate various embodiments of the present disclosure. As described in detail below, the disclosed turbine engine assembly 10 (e.g., a gas turbine engine, a liquid fueled aero-engine, etc.) may employ one or more fuel nozzles (e.g., turbine fuel nozzles) and one or more corrugated cyclone mixer assemblies (described presently), with an improved design to enhance premixing of the fuel, and control over the fuel-air profile, while reducing emissions (e.g., NOx) in the turbine engine assembly 10.
FIG. 1 depicts in diagrammatic form an exemplary turbine engine assembly 10 (high bypass type engine) utilized with aircraft having a longitudinal or axial centerline axis 11 therethrough for reference purposes. Assembly 10 preferably includes a core turbine engine, generally identified by numeral 12, and a fan section 14 positioned upstream thereof. Core engine 12 typically includes a generally tubular outer casing 16 that defines an annular inlet 18. Outer casing 16 further encloses and supports a booster compressor 20 for raising the pressure of the air that enters core engine 12 to a first pressure level. A high pressure, multi-stage, axial-flow high pressure compressor 21 receives pressurized air from booster 20 and further increases the pressure of the air. The pressurized air flows to a combustor 22, generally defined by a combustion liner 23, and including a fuel injection assembly 24, where fuel is injected into the pressurized air stream, via one or more fuel nozzles and corrugated cyclone mixer assemblies, to raise the temperature and energy level of the pressurized air. The high energy combustion products flow from combustor 22 to a first (high pressure) turbine 26 for driving high pressure compressor 21 through a first (high pressure) drive shaft 27, and then to a second (low pressure) turbine 28 for driving booster compressor 20 and fan section 14 through a second (low pressure) drive shaft 29 that is coaxial with first drive shaft 27. After driving each of turbines 26 and 28, the combustion products leave core engine 12 through an exhaust nozzle 30 to provide propulsive jet thrust.
Fan section 14 includes a rotatable, axial-flow fan rotor 32 that is surrounded by an annular fan casing 34. It will be appreciated that fan casing 34 is supported from core engine 12 by a plurality of substantially radially-extending, circumferentially-spaced outlet guide vanes 36. In this way, fan casing 34 encloses the fan rotor 32 and a plurality of fan rotor blades 38. A downstream section 40 of fan casing 34 extends over an outer portion of core engine 12 to define a secondary, or bypass, airflow conduit 42 that provides additional propulsive jet thrust.
From a flow standpoint, it will be appreciated that an initial air flow, represented by arrow 43, enters the turbine engine assembly 10 through an inlet 44 to fan casing 34. Air flow 43 passes through fan blades 38 and splits into a first compressed air flow (represented by arrow 45) and a second compressed air flow (represented by arrow 46) which enters booster compressor 20. The pressure of the second compressed air flow 46 is increased and enters high pressure compressor 21, as represented by arrow 47. After mixing with fuel and being combusted in combustor 22 combustion products 48 exit combustor 22 and flow through the first turbine 26. Combustion products 48 then flow through the second turbine 28 and exit the exhaust nozzle 30 to provide thrust for the turbine engine assembly 10.
During operation, the one or more fuel injection assemblies 24, intake the fuel from a fuel supply (e.g., liquid and/or gas fuel), mix the fuel with air, and distribute the air-fuel mixture into the one or more combustors 22 in a suitable ratio for optimal combustion, emissions, fuel consumption, and power output. As disclosed herein, the turbine engine assembly 10, and more particularly the fuel injection assembly 24, includes a mixer assembly having a corrugated cyclone mixer geometry (described presently).
Referring to the drawings and in particular to FIG. 2, illustrated is an exemplary combustor 50, generally similar to combustors 22 of FIG. 1. The combustor 50 includes a combustion chamber 52 in which combustor air is mixed with fuel and burned. The combustor 50 includes an outer liner 54 and an inner liner 56. The outer liner 54 defines an outer boundary of the combustion chamber 52, and the inner liner 56 defines an inner boundary of the combustion chamber 52. An annular dome, generally designated by 58, mounted upstream from the outer liner 54 and the inner liner 56 defines an upstream end of the combustion chamber 52. One or more fuel injector assemblies of the present disclosure, generally designated by 60, and generally similar to fuel injection assembly 24 of FIG. 1, are positioned on the dome 58. According to this disclosure, each of the fuel injector assemblies 60 includes a fuel nozzle assembly and a corrugated cyclone mixer assembly (described presently), disposed thereabout the fuel nozzle assembly. The corrugated cyclone mixer assembly 62 includes a corrugated geometry (described presently) for delivery of a mixture of fuel and air to the combustion chamber 52. Other features of the combustion chamber 52 are conventional and will not be discussed in further detail.
Illustrated in FIG. 3 is a first embodiment of a fuel injector assembly according to the disclosure. According to this disclosure, the fuel injector assembly 60 generally comprises a fuel nozzle assembly 61 and a corrugated cyclone mixer assembly 62 (generally shown as a shaded portion), disposed thereabout the fuel nozzle assembly 61. As illustrated, each fuel nozzle assembly 61 comprises a pilot mixer, generally designated by 63, and a main mixer, generally designated by 64, surrounding the pilot mixer 63. The pilot mixer 63 includes an annular pilot housing 66 having a hollow interior 68. A pilot fuel nozzle, generally designated by 70, is mounted in the annular pilot housing 66 along an axial centerline axis 71 of the fuel injector assembly 60. The fuel injector assembly 60 is axisymmetric about the axial centerline axis 71. The pilot fuel nozzle 70 includes a fuel injector 72 adapted for dispensing droplets of fuel into the hollow interior 68 of the pilot housing 66. It is envisioned that the fuel injector 72 may include an injector such as described in U.S. Pat. No. 5,435,884, which is hereby incorporated by reference.
In the illustrated embodiment, the pilot mixer 63 also includes a pair of concentrically mounted axial swirlers, generally designated by 76, 78, having a plurality of vanes 80, 82, respectively positioned upstream from the pilot fuel nozzle 70. The swirlers 76, 78 may have the same or different numbers of vanes 80, 82 without departing from the scope of the disclosure. Each of the vanes 80, 82 is skewed relative to the centerline 71 of the fuel injector assembly 60 for swirling air traveling through the pilot swirlers 76, 78 so it mixes with the droplets of fuel dispensed by the pilot fuel nozzle 70 to form a fuel-air mixture selected for optimal burning during ignition and low power settings of the engine. Although the pilot mixer 63 of the disclosed embodiment has two axial swirlers 76, 78, those skilled in the art will appreciate that the pilot mixer 63 may include more or less swirlers without departing from the scope of the present disclosure. As will further be appreciated by those skilled in the art, when more than one swirler is included in the pilot mixer, such as the illustrated swirlers 76, 78, the swirlers 76, 78 may be configured to swirl air in the same direction or in opposite directions. Further, the pilot interior 68 may be sized and the pilot inner and outer swirlers 76, 78 airflows and swirl angles may be selected to provide good ignition characteristics, lean stability and low CO and HC emissions at low power conditions.
A cylindrical barrier 84 is positioned between the swirlers 76, 78 for separating airflow traveling through the inner swirler 76 from that flowing through the outer swirler 78. The barrier 84 has a converging-diverging inner surface 86 which provides a fuel filming surface to aid in low power performance. Further, the housing 66 includes a generally diverging inner surface 88 adapted to provide controlled diffusion for mixing the pilot air with the main mixer airflow. The diffusion also reduces the axial velocities of air passing through the pilot mixer 63 and allows recirculation of hot gasses to stabilize the pilot flame.
The main mixer 64 includes a fuel injection assembly 60, including a fuel manifold 96, mounted in a fuel injection housing 98 between the pilot housing 66 and the corrugated cyclone mixer assembly 62. The fuel manifold 96 has a plurality of fuel injection ports 100 for introducing a fuel column 102, comprised of droplets of fuel, into a cavity 92 of the main mixer 64 defined between the fuel injection housing 98 and the corrugated cyclone mixer assembly 62. The fuel manifold 96 may have any number of fuel injection ports 100 without departing from the scope of the present disclosure. In one embodiment the fuel manifold 96 has a single circumferential row consisting of 10 evenly spaced ports. Although the ports 100 are arranged in a single circumferential row in the embodiment shown in FIG. 3, those skilled in the art will appreciate that they may be arranged in other configurations without departing from the scope of the present disclosure.
In an embodiment, by positioning the fuel injection housing 98 of the fuel manifold 96 between the pilot mixer 63 and the main mixer 64, the mixers are physically separated. As will also be appreciated by those skilled in the art, the distance between the pilot mixer 63 and the main mixer 64 may be selected to improve ignition characteristics, combustion stability at high and lower power and low CO and HC emissions at low power conditions.
As best illustrated in FIG. 3, and as previously described, the corrugated cyclone mixer assembly 62 is disposed about the fuel nozzle assembly 61. The corrugated cyclone mixer assembly 62 generally includes an annular housing 90 having disposed therein a swirler 110 positioned upstream from the plurality of fuel injection ports 100, a flange portion 91 and a corrugated lip portion 93 forming an outlet 94 downstream of the swirler 110. Although the swirler 110 may have other configurations without departing from the scope of the present disclosure, in one embodiment the swirler 110 is a radial swirler 111 having a plurality of radially skewed vanes 112 for swirling air traveling through the swirler 110 and mixing the swirled air passing therethrough with the droplets of fuel dispensed by the fuel ports 100 in the fuel injection housing 98 to form a fuel-air mixture selected for optimal burning during high power settings of the engine. Although the swirler 110 may have a different number of vanes 112 without departing from the scope of the present disclosure, in one embodiment the swirler has 40 vanes. The main mixer 64 is primarily designed to achieve low NO_xunder high power conditions by operating with a lean air-fuel mixture and by maximizing the fuel and air pre-mixing. The swirler 110 provides swirling of the incoming air through the radial vanes 112 to produce an upstream swirling air stream 114, as illustrated by directional arrow, and establishes the basic flow field of the combustor 50 (FIG. 2). During operation, fuel droplets are injected radially outward via fuel injection ports 100 into the swirling air stream 114 downstream from the swirler 110 as a fuel injection column 102, to produce a fuel/air stream 116.
As previously indicated, in contrast to known fuel injection assemblies, the novel fuel injection assembly 60 described herein includes the corrugated cyclone mixer assembly 62, disposed about the fuel nozzle assembly 61, and including lip portion 93 including a plurality of corrugations disposed at an aft end 95. The lip portion 93 is configured to include corrugations (described presently) that provide a multi-dimensional physical surface capable of introducing three dimensional vorticity to the fuel/air stream 116 passing therethrough the fuel injection assembly 60. The introduced three dimensional vorticity enhances the mixing process and can lead to lower NO_xemissions. The corrugated lip portion 93 may also provide an improvement in operability and reduce combustion dynamics by shifting the frequencies at which unsteady pressure waves exit the fuel nozzle assembly 61. This shifting of frequencies, in turn, may prevent the unsteady pressure fluctuations from coupling to heat release oscillations.
Referring now to FIGS. 4-10, illustrated in schematic illustrations, are various embodiments for the corrugated cyclone mixer assembly 62, and more particularly the lip portion 93 of the corrugated cyclone mixer assembly 62 according to various embodiments disclosed herein. In an embodiment, the corrugated cyclone mixer assembly 62 is constructed of a carbon steel. In an alternate embodiment, the corrugated cyclone mixer assembly 62 may be constructed of any sufficiently durable material capable of withstanding the high temperatures, pressures and abrasions encountered during the mixing process. Alternate materials may include, but are not limited to plastics such as polycarbonates and urethanes, metals such as aluminum, steel, stainless steel and ferro-nickel alloys and ceramics. In an embodiment, the cyclone mixer assembly 92 is fabricated using additive manufacturing techniques.
Referring more specifically to FIGS. 4 and 5, illustrated are embodiments of a portion of a corrugated cyclone mixer assembly 120 and 122, respectively, generally similar to corrugated cyclone mixer assembly 62 of FIG. 3. In this particular embodiment, the corrugated cyclone mixer assemblies 120, 122 are configured as purely radial extending corrugated cyclone mixers 121. More specifically, each of the corrugated cyclone mixer assemblies 120, 122 includes a lip portion 124, 126, respectively.
Referring more specifically to FIG. 4, in the illustrated embodiment, the lip portion 124 includes a plurality of sinusoidal radial extending corrugations 128. In this particular embodiment, the corrugations 128 are generally uniformly spaced, circumferentially about the lip portion 124 as indicated at “A”. In an alternate embodiment, the corrugations 128 are not uniformly spaced, circumferentially about the lip portion 124. In addition, as illustrated, the corrugations 128 are configured to extend radially, as indicated at “B”. In this particular embodiment, the corrugations 128 are illustrated as extending a uniformly radial amount “B”, circumferentially and radially about the lip portion 124. In an alternate embodiment, the corrugations 128 do not extend a uniformly a radially amount, circumferentially about the lip portion 124, and may extend various radial dimensions. As previously indicated, the corrugations 128 are configured as sinusoidal configured elements. In an alternate embodiment, described presently, the corrugations 128 may be configured to include sharp peaks and valley, and described as “shark teeth”, circumferentially about the lip portion 124. In yet another embodiment, the radial corrugations 128 may include a mix of sinusoidal corrugations and shark teeth corrugations.
Referring more particularly to FIG. 5, as illustrated, in this particular embodiment, the corrugated cyclone mixer assembly 122 is configured as including a plurality of sinusoidal, radial extending corrugations 128, similar to the embodiment of FIG. 4. In this particular embodiment, the radial corrugations 128 are configured uniformly circumferentially about only a portion of the lip portion 126 as a means for enhancing the turbulent air/fuel mixing. As illustrated the corrugated cyclone mixer assembly 122 is configured axisymmetric about an axial centerline axis 125.
Referring now to FIG. 6, illustrated is an alternate embodiment of a corrugated cyclone mixer assembly 130, generally similar to the corrugated cyclone mixer assembly 62 of FIG. 3, configured axisymmetric about an axial centerline axis 136. In this particular embodiment, and in contrast to the embodiments of FIGS. 4 and 5, the corrugated cyclone mixer assembly 130 is configured as a radial/tangential corrugated cyclone mixer, and described as including both radial and tangential directional components to the corrugations. More specifically, as illustrated the corrugated cyclone mixer assembly 130 includes a lip portion 132 including a plurality of sinusoidal radially/tangentially extending corrugations 134, and more specifically including a radial and tangential component as indicated by the directional arrows 137 and 138, respectively. In this particular embodiment, the corrugations 134 are generally uniformly spaced, circumferentially about the lip portion 132, but may be non-uniformly spaced as previously indicated with regard to FIGS. 4 and 5. Similarly, the corrugations 134 may be configured circumferentially about only a portion of the lip portion 132 as indicated in FIG. 5. The corrugations 134 of FIG. 6 may be described as radial/tangential corrugations.
Referring now to FIGS. 7 and 8, illustrated are side schematic views of alternate embodiments of a corrugated cyclone mixer assembly, designated 140 and 150, generally similar to the corrugated cyclone mixer assembly 62 of FIG. 3. In this particular embodiment, and in contrast to the embodiments of FIGS. 4-6, the corrugated cyclone mixer assemblies 140 and 150 are configured as purely axial corrugated cyclone mixers. More specifically, as best illustrated in FIG. 7, the corrugated cyclone mixer assembly 140 includes a lip portion 142 including a plurality of sinusoidal axially extending corrugations 144 configured extending axially relative to a longitudinal axis 146. In this particular embodiment, the corrugations 144 are configured in an alternating pattern, extending axially upstream and including a downstream cooperating corrugation and generally uniformly spaced, circumferentially about the lip portion 142, but may be non-uniformly spaced as previously indicated with regard to FIGS. 4-6. Similarly, the plurality of sinusoidal purely axially extending corrugations 144 may be non-uniformly configured about the lip portion 142 as described in FIG. 5. The corrugations 144 of FIG. 7 may be described as purely axial corrugations. As illustrated, the plurality of sinusoidal axially extending corrugations 144 are integrally disposed at an aft end of the lip portion 142. In an embodiment, each sinusoidal axially extending corrugation 144 includes an apex 141, and a pair of circumferentially or laterally opposite trailing edges or sides 145 converging from a base 143 to the respective apex 141 in one of the downstream, aft direction or as a cutout in an upstream, forward direction. Each sinusoidal axially downstream extending corrugation 144 also includes a radially outer or first substantially semi-circular surface 147, and a radially opposite inner or substantially semi-circular surface 148 bounded by the trailing edges 145 and base 143. The adjacent corrugations 144 are spaced circumferentially or laterally about at least a portion of the lip portion 142, and disposed in flow communication with the inside of the corrugated cyclone mixer assembly 140 for channeling flow radially therethrough. In an embodiment, each sinusoidal axially downstream extending corrugation 144 may not be formed as “purely axial” and include a concave contour axially between the respective bases 143 and apexes 141 and/or a concave contour circumferentially or laterally between the trailing edges 145. In another embodiment not formed as “purely axial”, each of the sinusoidal axially downstream extending corrugation 144 may include a compound, three-dimensional flow surface contour defining a shallow concave depression or bowl for promoting mixing effectiveness. Each sinusoidal axially extending corrugation 144 has an axial length “C” measured perpendicularly from its base 143 to its apex 141, and a lateral width “D” varying from a maximum value at the base to a minimum value at the apex.
In contrast to the sinusoidal purely axial corrugations of FIG. 7, in FIG. 8, illustrated is the corrugated cyclone mixer assembly 150 including a plurality of non-sinusoidal or shark teeth configured, axial corrugations 154, being substantially triangular in configuration. More specifically, as best illustrated in FIG. 8, the corrugated cyclone mixer assembly 150 includes a lip portion 152 including the plurality of shark teeth configured, axial corrugations 154 configured extending axially relative to a longitudinal axis 156. As illustrated, the plurality of axial corrugations 154 are integrally disposed at an aft end of the lip portion 152, that in combination define the shark-tooth configuration. In an embodiment, each axial corrugation 154 includes an apex 151, and a pair of circumferentially or laterally opposite trailing edges or sides 155 converging from a base 153 to the respective apex 151 in the downstream, aft direction. Each axial corrugation 154 also includes a radially outer or first triangular surface 157, and a radially opposite inner or second triangular surface 158 bounded by the trailing edges 155 and base 153. The trailing edges 155 of adjacent corrugations 154 are spaced circumferentially or laterally apart from the bases 153 to apexes 151 to define respective slots or cut-outs 159 diverging laterally and axially, and disposed in flow communication with the inside of the corrugated cyclone mixer assembly 150 for channeling flow radially therethrough. In the exemplary embodiment illustrated in FIG. 8, the slots 159 are also triangular and complementary with the triangular axial corrugations 154 and diverge axially aft from a slot base, which is circumferentially coextensive with the bases 153, to the corrugation apexes 151. In an embodiment, each corrugation 154 may not be formed as “purely axial” and include a concave contour axially between the respective bases 153 and apexes 151 and/or a concave contour circumferentially or laterally between the trailing edges 155. In another embodiment not formed as “purely axial”, each of the axial corrugations 154 may include a compound, three-dimensional flow surface contour defining a shallow concave depression or bowl for promoting mixing effectiveness. Each axial corrugations 154 has an axial length “E” measured perpendicularly from its base 153 to its apex 151, and a lateral width “F” varying from a maximum value at the base to a minimum value at the apex.
Referring now to FIGS. 9 and 10, illustrated are yet additional embodiments of a corrugated cyclone mixer assembly including a plurality of corrugations about an aft end of the lip portion, generally referenced 160 and 170, respectively. In the embodiment of FIG. 9, the corrugated cyclone mixer assembly 160 includes a plurality of non-sinusoidal or shark teeth configured, radially outward extending corrugations 164. More specifically, as best illustrated in FIG. 9, the corrugated cyclone mixer assembly 160 includes a lip portion 162 including the plurality of shark teeth configured, radially outward corrugations 164 configured extending radially outward relative to a longitudinal axis 166. As illustrated, the plurality of axial corrugations 164 include a plurality of apexes 168 and a plurality of bases 169, such as those previously described with regard to FIG. 8, that in combination define the shark-tooth configuration. In an alternate embodiment, the corrugations 164 may be configured having a sinusoidal geometry as previously described.
In contrast to the radially outward corrugations of FIG. 9, in FIG. 10, illustrated is the corrugated cyclone mixer assembly 170 including a plurality of non-sinusoidal or shark teeth configured, radially inward extending corrugations 174. More specifically, as best illustrated in FIG. 10, the corrugated cyclone mixer assembly 170 includes a lip portion 172 including the plurality of shark teeth configured, radially inward extending corrugations 174 configured extending radially inward relative to a longitudinal axis 176. As illustrated, the plurality of radially inward corrugations 174 include a plurality of apexes 178 and a plurality of bases 179 that in combination define the shark-tooth configuration. In an alternate embodiment, the corrugations 174 may be configured having a sinusoidal geometry as previously described.
As emissions regulations tighten, hardware known for lower emissions will become increasingly important. Accordingly, as disclosed herein and as illustrated in FIGS. 1-10 provided are various technological advantages and/or improvements over existing fuel injection assemblies, and in particular mixer assemblies and fuel/air mixing. The disclosure provides an improved corrugated cyclone mixer assembly to enhance the mixing of the fuel flowing from a fuel injector with air supplied via a swirler to the combustion chamber and thus reduces production of undesirable emissions such as oxides of nitrogen or NO_x. In addition, the improved corrugated cyclone mixer provides increased premixing that is downstream of the corrugated cyclone mixer without increasing the risk of autoignition that may lead to improved durability of the hardware, and thereby a reduction in the need for maintenance or replacement.
A further benefit of the disclosure lies in the many variable corrugation configurations of the corrugated cyclone mixer, including, but not limited to, purely radial corrugations, purely axial corrugations, axial and tangential corrugations, sinusoidal corrugations, sharp “shark teeth” like corrugations, radial inward extending corrugations, radially outward extending corrugations, uniform and non-uniform corrugations configurations, flat or contoured corrugations, or combinations of any of the above listed corrugation geometries, etc. In addition, the corrugations as disclosed herein may be configured having a substantially uniform thickness which may also be equal to the thickness of the flange portion 91 of the annular housing 90 from which they extend, and may be formed of one or more thin walled members or plates. Alternatively, the corrugations may vary in thickness to allow for structural rigidity and flow surface blending. Although the individual corrugations, for example, could be flat components, as previously mentioned, the corrugations may include a compound curvature for cooperating with the fluid flow for promoting mixing effectiveness while at the same time providing an aerodynamically smooth and non-disruptive profile for minimizing losses in aerodynamic efficiency and performance. In the disclosed embodiment, each corrugation has an axial length measured perpendicularly from its base to its apex or outermost point and a lateral width varying from a maximum value at the base to a minimum value at the apex or outermost point. Additionally, the corrugations preferably have equal axial lengths from the bases to the apexes, however, the corrugation lengths may be unequal and vary as desired.
The many varied configurations provide that the NO_xperformance can be optimized. As a result of the above, various embodiments of the present disclosure may allow extended combustor operating conditions, extend the life and/or maintenance intervals for various combustor components, maintain adequate design margins of flame holding, and/or reduce undesirable emissions. In addition, improved fuel-air mixing is also expected to yield better efficiency at a cruise condition.
This written description uses examples to disclose the disclosure, including the best mode, and also to enable any person skilled in the art to practice the disclosure, including making and using any devices or systems and performing any incorporated methods. The patentable scope 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 include 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 language of the claims.
Exemplary embodiments of a corrugated cyclone mixer are described in detail above. The corrugated cyclone mixers are not limited to use with the specified turbine containing systems described herein, but rather, the corrugated cyclone mixers can be utilized independently and separately from other turbine containing system components described herein. Moreover, the present disclosure is not limited to the embodiments of the corrugated cyclone mixers described in detail above. Rather, other variations of corrugated cyclone mixers embodiments may be utilized within the spirit and scope of the claims.
While the disclosure has been described in terms of various specific embodiments, those skilled in the art will recognize that the disclosure can be practiced with modification within the spirit and scope of the claims.

Claims

What is claimed is:

1. A corrugated cyclone mixer assembly for use in a fuel injection assembly of a turbine engine, the assembly comprising:

an annular housing comprising a flange portion and a lip portion configured downstream of the flange portion; and

a swirler disposed therein the annular housing for inducing a cyclonic motion in the corrugated cyclone mixer assembly, the swirler configured upstream of the flange portion and including a plurality of swirler vanes to produce a swirling air flow,

the lip portion forming an outlet downstream of the swirler and including a plurality of corrugations at an aft end, the plurality of corrugations configured to mix the swirling air flow and an injected fuel stream flowing therethrough the corrugated cyclone mixer assembly.

2. The corrugated cyclone mixer assembly as claimed in claim 1, wherein the plurality of corrugations comprise a plurality of purely radially extending corrugations.

3. The corrugated cyclone mixer assembly as claimed in claim 1, wherein the plurality of corrugations comprise a plurality of purely axially extending corrugations.

4. The corrugated cyclone mixer assembly as claimed in claim 1, wherein the plurality of corrugations comprise a plurality of radially and tangentially extending corrugations.

5. The corrugated cyclone mixer assembly as claimed in claim 1, wherein the plurality of corrugations comprise a plurality of radially outwardly extending corrugations.

6. The corrugated cyclone mixer assembly as claimed in claim 1, wherein the plurality of corrugations comprise a plurality of radially inwardly extending corrugations.

7. The corrugated cyclone mixer assembly as claimed in claim 1, wherein the plurality of corrugations are configured substantially uniformly spaced circumferentially about the lip portion.

8. The corrugated cyclone mixer assembly as claimed in claim 1, wherein the plurality of corrugations are configured having a uniform length, extending from an apex to a base, in at least one of a radial or axial direction.

9. The corrugated cyclone mixer assembly as claimed in claim 1, wherein the plurality of corrugations are configured as at least one of sinusoidal corrugations or substantially triangular corrugations.

10. A fuel injection assembly for use in a combustor of a turbine engine, the fuel injection assembly comprising:

a fuel nozzle assembly including a main housing and defining an annular cavity, the fuel nozzle assembly comprising;

a fuel manifold in fluid communication with a source of fuel; and

a plurality of fuel injection ports, each fuel injection port configured to introduce a fuel column into the annular cavity; and

a corrugated cyclone mixer assembly disposed about the fuel nozzle, the corrugated cyclone mixer assembly comprising;

11. The fuel injection assembly as claimed in claim 10, wherein the plurality of corrugations comprise at least one of a plurality of purely radially extending corrugations or a plurality of purely axially extending corrugations.

12. The fuel injection assembly as claimed in claim 10, wherein the plurality of corrugations include a plurality of radially and tangentially extending corrugations.

13. The fuel injection assembly as claimed in claim 10, wherein the plurality of corrugations comprise at least one of a plurality of radially outwardly extending corrugations or a plurality of radially inwardly extending corrugations.

14. The fuel injection assembly as claimed in claim 10, wherein the plurality of corrugations are configured substantially uniformly spaced circumferentially about the lip portion.

15. The fuel injection assembly as claimed in claim 10, wherein the plurality of corrugations are configured having a uniform length, extending from an apex to a base, in at least one of a radial or axial direction.

16. The fuel injection assembly as claimed in claim 10, wherein the plurality of corrugations are configured as at least one of sinusoidal corrugations or substantially triangular corrugations.

17. A turbine engine assembly comprising:

a compressor section;

a combustor section; and

a turbine section, wherein the compressor section, the combustor section and the turbine section are configured in a downstream axial flow relationship, the combustor section comprising:

a combustion chamber; and

a fuel injection assembly disposed in the combustion chamber, the fuel injection assembly comprising:

a fuel manifold in fluid communication with a source of fuel; and

18. The turbine engine assembly as claimed in claim 17, wherein the plurality of corrugations comprise at least one of a plurality of purely radially extending corrugations, a plurality of purely axially extending corrugations, a plurality of radially and tangentially extending corrugations, a plurality of radially outwardly extending corrugations or a plurality of radially inwardly extending corrugations.

19. The turbine engine assembly as claimed in claim 18, wherein the plurality of corrugations are configured as at least one of sinusoidal corrugations or substantially triangular corrugations.

20. The turbine engine assembly as claimed in claim 17, wherein the assembly comprises a gas turbine engine.