MULTITUBE PILOT INJECTOR HAVING A FLAME ANCHOR FOR A GAS TUBINE ENGINE
An injector for a combustor of a gas turbine engine is provided with a plurality of air/fuel mixing tubes divided into radially outer and radially inner subsets of air/fuel mixing tubes with a first fuel manifold in fluid communication with the radially outer subset of air/fuel mixing tubes and a second fuel manifold in fluid communication with the radially inner subset of air/fuel mixing tubes. A blocker is provided at an outlet portion of each of the air/fuel mixing tubes of the radially outer subset of air/fuel mixing tubes and/or the radially inner subset of air/fuel mixing tubes to form a flame anchoring surface.
The present disclosure relates generally to gas turbine engines and, more particularly, to injectors used to inject a mixture of compressed air and fuel into a combustor in the gas turbine engines.
Gas turbine engines are used to generate mechanical energy by combusting a fuel/air mixture within a combustor. Fuel and compressed air are delivered to the combustor through one or more fuel injectors. In one type of gas turbine engine disclosed in U.S. Pat. No. 9,752,781, main fuel injectors are located radially outward of a combustion liner in a combustor and are spread in an annular array about the combustion liner. A hemispheric combustor dome assembly is positioned at an inlet end of the combustion liner and reverses the direction of flow of a fuel/air mixture from the main fuel injectors. The hemispheric combustor dome assembly then directs the fuel/air mixture flow into an inlet end of the combustion liner through a series of passageways. A pilot fuel nozzle is positioned along a center axis of the combustion liner is used to ignite, support and maintain one or more stages of the fuel/air mixture from the main fuel injectors within the combustion liner. While the gas turbine engine disclosed in U.S. Pat. No. 9,752,781 is advantageous in that it allows for greater control of the velocity of the fuel/air mixture entering the combustion liner, which can lead to greater control over the power generated and reductions in the production of undesired oxides of nitrogen and carbon monoxide, further improvements in the control of the flue/air mixture would be desirable.
BRIEF DESCRIPTIONThis brief description is provided to introduce a selection of concepts in a simplified form that are further described in the detailed description below. This brief description is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Other aspects and advantages of the present disclosure will be apparent from the following detailed description of the embodiments and the accompanying figures.
Aspects of the disclosure relate to a gas turbine engine including a combustor having one or more fuel injectors. More particularly, aspects are directed to a multitube pilot injector that reduces thermal stresses and combustor emissions while improving combustor performance and efficiency.
In another aspect, the disclosure is directed to an injector for a combustor of a gas turbine engine comprising: a plurality of air/fuel mixing tubes including a radially outer subset of air/fuel mixing tubes and a radially inner subset of air/fuel mixing tubes; a first fuel manifold in fluid communication with the radially outer subset of air/fuel mixing tubes; a second fuel manifold in fluid communication with the radially inner subset of air/fuel mixing tubes; and a blocker at an outlet portion of each of the air/fuel mixing tubes of the radially outer subset of air/fuel mixing tubes and/or the radially inner subset of air/fuel mixing tubes.
In another aspect, the disclosure is directed to a combustor for a gas turbine engine and comprising: a generally cylindrical flow sleeve; a generally cylindrical combustion liner positioned radially inward from the flow sleeve and defining a combustion zone; a first injector that is generally annularly shaped and surrounds the combustion liner and is positioned at a downstream end of the flow sleeve, and a second injector that is positioned radially inward of the combustion liner at an inlet end of the combustion zone to receive the compressed air from the radially outward openings in the first injector following the radially outward path. The first injector comprises: radially outward openings to allow passage of compressed air following a radially outward path; and radially inward openings to allow passage of compressed air following a radially inward path. The second injector comprises: a plurality of air/fuel mixing tubes including a radially outer subset of air/fuel mixing tubes and a radially inner subset of air/fuel mixing tubes; a first fuel manifold in fluid communication with the radially outer subset of air/fuel mixing tubes; a second fuel manifold in fluid communication with the radially inner subset of air/fuel mixing tubes; and a blocker at an outlet portion of each of the air/fuel mixing tubes of the radially outer subset of air/fuel mixing tubes and/or the radially inner subset of air/fuel mixing tubes.
The present technology is described in detail below with reference to the attached drawing figures, in which like numerals represent the same components, and wherein:
Turning now to the drawings in greater detail, and initially to
As best understood with reference to
The second injector 104 generally includes an inlet portion 116 configured to receive compressed air flowing in the radially outer path 112, an outlet portion 118 configured to supply a fuel/air mixture to the combustion zone 110 where it is ignited and supports a flame near the central axis of the combustor 100, and an air/fuel mixing portion 120 generally extending between the inlet portion 116 and the outlet portion 118.
As best seen in
The second injector 104 also includes a first fuel manifold 130 and a second fuel manifold 132, each in fluid communication with one or more of the plurality of air/fuel mixing tubes 122 via a corresponding one or more fuel feed tubes 134 and 136. For example, in the depicted embodiment the first fuel manifold 130 is in fluid communication with a radially outwardly located subset of the plurality of air/fuel mixing tubes 122 (i.e., the “outer diameter” or “OD” subset of the air/fuel mixing tubes 122) via the fuel feed tube(s) 134, while the second fuel manifold 132 is in fluid communication with a radially inwardly located subset of the plurality of air/fuel mixing tubes 122 (i.e., the “inner diameter” or “ID” subset of the air/fuel mixing tubes 122) via the fuel feed tube(s) 136. In this regard, the combustor 100 can be staged by selectively injecting fuel into the OD or ID subset of the air/fuel mixing tubes 122 via the first and second fuel manifolds 130, 132, respectively, which in turn will be ignited in the combustion chamber 110 forming two separately supported and localized flames (i.e., an annular outer flame surrounding a centrally located inner flame).
The second injector 104 may be manufactured by any desired means such as, in one non-limiting example, by additive manufacturing. In this regard, the second injector 104 would be built up layer by layer in the substantially vertical direction as it appears in
As best shown in
Among other benefits, the first and second static air plenums 140, 142 may beneficially serve as a buffer between the hot compressed air flowing through the air/fuel mixing tubes 122 and the cool fuel provided in the first and second fuel manifolds 130, 132. That is, the first and second static air plenums 140, 142 insulate the air/fuel mixing tubes 122 from the cold fuel, thereby improving the strength and stress resistance of the tubes near the cold first and second fuel manifolds 130, 132.
In the embodiment shown in
As shown in
In some embodiments, the plurality of air/fuel mixing tubes used to mix and deliver fuel and air may be structured and configured differently than that shown in
More particularly,
In the
Although the embodiments described thus far have included air/fuel mixing tubes 122, 222 having a substantially circular cross-sectional area, embodiments are not so limited and in other embodiments the air-fuel mixture tubes may have other cross-sectional area configurations without departing from the scope of the disclosure. For example,
In some embodiments, one or more flow modifiers may be included along the length of the air/fuel mixture mixing tubes 122, such as in the upstream portion 124 prior to the 45-degree bend, in order to, e.g., create turbulence and improve air and fuel mixing within the respective tube. This may be more readily understood with respect to
In this embodiment the flow modifier 354 includes a substantially saw-tooth type pattern, with a main wedge portion 356 and a serrated end portion 358. As compressed air passes over the wedge portion 356, it speeds up and is directed toward a central portion of the respective air/fuel mixing tube 322a. As it travels over the serrated end portion 356, the sawtooth pattern results in the airflow creating trapped vortices near the serrated end portion 358, as illustrated by the airflow diagram 360 in
Although the sawtooth pattern is illustrated in
In some embodiments, particularly embodiments in which the second injector includes air/fuel mixing tubes having substantially quadrilateral cross-sectional areas, an exit profile of the air/fuel mixing tube may be modified to include one or more surfaces to encourage flame anchoring at the exit face of the injector. This will be more readily understood with reference to
In
In
In
In
Although embodiments of the second injector discussed and shown herein include air/fuel mixing tubes that each include two fuel feed tubes in fluid communication with a respective fuel manifold, embodiments are not so limited. In other embodiments, each air/fuel mixing tube can include one fuel feed tube or else more than one fuel feed tube. For example,
From the foregoing, it will be seen that this disclosure is one well adapted to attain all the ends and objects set forth above, together with other advantages which are obvious and inherent to the system and method. It will be understood that certain features and sub-combinations are of utility and may be employed without reference to other features and sub-combinations.
Additional Considerations
In this description, references to “one embodiment,” “an embodiment,” or “embodiments” mean that the feature or features being referred to are included in at least one embodiment of the technology. Separate references to “one embodiment,” “an embodiment,” or “embodiments” in this description do not necessarily refer to the same embodiment and are also not mutually exclusive unless so stated and/or except as will be readily apparent to those skilled in the art from the description. For example, a feature, structure, act, etc. described in one embodiment may also be included in other embodiments but is not necessarily included. Thus, the current technology can include a variety of combinations and/or integrations of the embodiments described herein.
In the specification and claims, reference will be made to several terms, which shall be defined to have the following meanings. The singular forms “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise. “Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event occurs and instances where it does not.
Approximating language, as used herein throughout the specification and the claim, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about,” “approximately,” and “substantially” are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Range limitations may be combined and/or interchanged. Such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise.
As used herein, the terms “axial” and “axially” refer to directions and orientations extending substantially parallel to a center longitudinal axis of the combustor. The terms “radial” and “radially” refer to directions and orientations extending substantially perpendicular to the central axis. Moreover, directional references, such as, “top,” “bottom,” “front,” “back,” “side,” and similar terms are used herein solely for convenience and should be understood only in relation to each other. For example, a component might in practice be oriented such that faces referred to herein as “top” and “bottom” are in practice sideways, angled, inverted, etc. relative to the chosen frame of reference.
The terms “coupled,” “fixed,” “attached to,” and the like refer to both direct coupling, fixing, or attaching, as well as indirect coupling, fixing, or attaching through one or more intermediate components or features, unless otherwise specified herein.
Although the present application sets forth a detailed description of numerous different embodiments, it should be understood that the legal scope of the description is defined by the words of the claims and equivalent language. The detailed description is to be construed as exemplary only and does not describe every possible embodiment because describing every possible embodiment would be impractical. Numerous alternative embodiments may be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims.
Throughout this specification, plural instances may implement components, operations, or structures described as a single instance. Although individual operations of one or more methods are illustrated and described as separate operations, one or more of the individual operations may be performed concurrently, and nothing requires that the operations be performed in the order recited or illustrated. Structures and functionality presented as separate components in example configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements fall within the scope of the subject matter herein. The foregoing statements in this paragraph shall apply unless so stated in the description and/or except as will be readily apparent to those skilled in the art from the description.
As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Although the disclosure has been described with reference to the embodiments illustrated in the attached figures, it is noted that equivalents may be employed, and substitutions made herein, without departing from the scope of the disclosure as recited in the claims.
Claims
1. An injector for a combustor of a gas turbine engine comprising:
- a plurality of air/fuel mixing tubes including a radially outer subset of air/fuel mixing tubes and a radially inner subset of air/fuel mixing tubes;
- a first fuel manifold in fluid communication with the radially outer subset of air/fuel mixing tubes;
- a second fuel manifold in fluid communication with the radially inner subset of air/fuel mixing tubes; and
- a blocker at an outlet portion of each of the air/fuel mixing tubes of the radially outer subset of air/fuel mixing tubes and/or the radially inner subset of air/fuel mixing tubes.
2. The injector of claim 1, wherein four neighboring blockers are provided proximate one another to form a flame anchoring surface.
3. The injector of claim 2, wherein the flame anchoring surface is a substantially circular flame anchoring surface.
4. The injector of claim 2, wherein the blocker is an arcuate, a triangular or a rectangular surface.
5. The injector of claim 2, wherein each of the air/fuel mixing tubes of the radially outer subset of air/fuel mixing tubes have a substantially quadrilateral cross-sectional area and the blockers are at the outlet portion of each of the air/fuel mixing tubes of the radially outer subset of air/fuel mixing tubes.
6. The injector of claim 5, wherein each of the air/fuel mixing tubes of the radially inner subset of air/fuel mixing tubes have a substantially circular cross-sectional area.
7. The injector of claim 2, including a plurality of static air plenums, each static air plenum surrounding a corresponding one of the plurality of air/fuel mixing tubes such that each air/fuel mixing tube is thermally isolated from the respective fuel manifold via the corresponding static air plenum.
8. The injector of claim 2, further comprising a plurality of substantially L-shaped fuel feed tubes, wherein each of the fuel feed tubes comprises an upstream portion, a downstream portion, and an elbow portion that connects the upstream portion to the downstream portion at an oblique angle, each of the fuel feed tubes provides fluid communication between a downstream edge of one of the first manifold or the second manifold and one of the plurality of air/fuel mixing tubes, and each of the fuel feed tubes does not extend through any of the plurality of the static air plenums.
9. The injector of claim 8, wherein the downstream portion of at least some of the plurality of air/fuel mixing tubes includes a swirled profile defining a substantially helical air/fuel flow path.
10. The injector of claim 8, wherein a distal portion of each of fuel feed tubes is oriented approximately normal to the one of the plurality of air/fuel mixing tubes so that fuel is injected cross-stream into a flow of compressed air within the one of the plurality of air/fuel mixing tubes.
11. The injector of claim 2, including a series of spaced-apart ribs positioned at an inlet of each of the static air plenums and connecting each of the air/fuel mixing tubes with a body of the injector surrounding the static air plenum.
12. The injector of claim 2, including internal baffle plates positioned within the first fuel manifold and the second fuel manifold and having a plurality of through-holes for fluid flow through the baffle plates.
13. The injector of claim 2, wherein the plurality of air/fuel mixing tubes includes a radially outer subset of air/fuel mixing tubes in fluid communication with first fuel manifold and having a substantially quadrilateral cross-sectional profile and a radially inner subset of air/fuel mixing tubes in fluid communication with the second fuel manifold and having a substantially circular cross-sectional profile.
14. The injector of claim 13 wherein each of the air/fuel mixing tubes of the radially outer subset of air/fuel mixing tubes includes at least one flow modifier at an inlet of the air/fuel mixing tube for inducing turbulence in compressed air passing through the air/fuel mixing tube upstream of a portion where fuel is injected into the air/fuel mixing tube.
15. The injector of claim 2, wherein the first fuel manifold and the second fuel manifold are annular in configuration and nested together with the second fuel manifold positioned radially inwardly from the first fuel manifold.
16. The injector of claim 1, including a third fuel manifold and a radially intermediate subset of the air/fuel mixing tubes, wherein the first fuel manifold is in fluid communication with each of the radially outer, radially intermediate, and radially inner subsets of air/fuel mixing tubes, the second fuel manifold is in fluid communication with only the radially inner subset of air/fuel mixing tubes, and the third fuel manifold is in fluid communication with only the radially inner and the radially intermediate subsets of air/fuel mixing tubes.
17. A combustor for a gas turbine engine and comprising:
- a generally cylindrical flow sleeve;
- a generally cylindrical combustion liner positioned radially inward from the flow sleeve and defining a combustion zone;
- a first injector that is generally annularly shaped and surrounds the combustion liner and is positioned at a downstream end of the flow sleeve, the first injector comprising: radially outward openings to allow passage of compressed air following a radially outward path; radially inward openings to allow passage of compressed air following a radially inward path; and
- a second injector that is positioned radially inward of the combustion liner at an inlet end of the combustion zone to receive the compressed air from the radially outward openings in the first injector following the radially outward path, the second injector comprising: a plurality of air/fuel mixing tubes including a radially outer subset of air/fuel mixing tubes and a radially inner subset of air/fuel mixing tubes; a first fuel manifold in fluid communication with the radially outer subset of air/fuel mixing tubes; and a second fuel manifold in fluid communication with the radially inner subset of air/fuel mixing tubes; and a blocker at an outlet portion of each of the air/fuel mixing tubes of the radially outer subset of air/fuel mixing tubes and/or the radially inner subset of air/fuel mixing tubes.
18. The combustor of claim 17, wherein four neighboring blockers are provided proximate one another to form a flame anchoring surface.
19. The combustor of claim 18, wherein the flame anchoring surface is a substantially circular flame anchoring surface.
20. The combustor of claim 18, wherein the blocker is an arcuate, a triangular or a rectangular surface.
Type: Application
Filed: Nov 3, 2022
Publication Date: Dec 21, 2023
Inventors: Bryan KALB (Jupiter, FL), Matthew YAQUINTO (Jupiter, FL), Gene CHONG (Jupiter, FL), David PARADES (Jupiter, FL), James BRACKETT (Palm Beach, FL), Gregory VOGEL (Palm Beach Gardens, FL), Hany RIZKALLA (Stuart, FL), Bernard Tam Yen SAM (Jupiter, FL), Ramesh KESHAVA-BHATTU (Jupiter, FL), Fred HERNANDEZ (Jupiter, FL), Joshua R. MCNALLY (Jupiter, FL)
Application Number: 17/980,263