Patent Application
20180112875
The present disclosure generally relates to a combustor for a gas turbine engine. More particularly, the present disclosure relates to combustor assembly including an air shield for a radial or axially offset fuel injector.
A gas turbine engine generally includes a compressor section, a combustion section, and a turbine section. The compressor section progressively increases the pressure of the air entering the gas turbine engine and supplies this compressed air to the combustion section. The compressed air and a fuel (e.g., natural gas) mix within the combustion section before burning in one or more combustion chambers to generate high pressure and high temperature combustion gases. The combustion gases flow from the combustion section into the turbine section where they expand to produce mechanical rotational energy. For example, expansion of the combustion gases in the turbine section may rotate a rotor shaft connected, e.g., to a generator to produce electricity.
The combustion section typically includes a plurality of annularly arranged combustors, each of which receives compressed air from the compressor section. Each combustor may include a liner positioned within a combustor casing. The liner at least partially defines a combustor chamber having a primary combustion zone and a secondary combustion zone positioned downstream from the primary combustion zone. One or more fuel nozzles may supply the fuel to each of the primary combustion zone. Furthermore, one or more radial fuel injectors, axially offset or axially staged from the one or more fuel nozzle(s) and positioned downstream from the one or more fuel nozzles may supply the a secondary fuel and air mixture to the secondary combustion zone.
A tube or conduit may be used to supply fuel to a respective radial fuel injector. A first or upstream end of the tube may be rigidly connected to a casing structure, a fuel supply or to a flow sleeve which at least partially surrounds the liner. A second end of the tube may be rigidly connected to the fuel injector which is connected to an impingement sleeve which also partially surrounds the a portion of the liner. An expansion joint is defined between the flow sleeve and the impingement sleeve. As the combustor transitions through various thermal conditions, there may be relative axial and/or radial movement between the flow sleeve and the impingement sleeve at the expansion joint, thereby placing a mechanical load on the tube.
Aspects and advantages are set forth below in the following description, or may be obvious from the description, or may be learned through practice.
One embodiment of the present disclosure is a combustor assembly. The combustor assembly includes a combustion liner that is at least partially surrounded by a flow sleeve and an impingement sleeve. An axial expansion joint is defined between an aft end of the flow sleeve and a forward end of the impingement sleeve. A radial fuel injector extends radially through the impingement sleeve and at least partially through the combustion liner. The radial fuel injector is fluidly coupled to a fuel conduit that extends across the expansion joint. The combustor assembly further includes an air shield assembly. The air shield assembly includes a forward end that is slideably connected to the flow sleeve, an aft end that is rigidly connected to at least one of the combustion liner, the radial fuel injector and the impingement sleeve, and a bridge member that connects the forward end of the air shield assembly to the aft end of the air shield assembly. The bridge member extends across the expansion gap and the fuel conduit is at least partially disposed within the bridge member.
Another embodiment of the present disclosure is a combustor air shield assembly. The combustor air shield assembly includes a base including a forward bracket, an aft bracket and a base bridge member structurally linking the forward bracket to the aft bracket and a cap that includes a forward sleeve, an injector cover and a cap bridge member structurally linking the forward sleeve to the injector cover. The base bridge member, the cap bridge member, the air shield and the injector cover define an air flow passage therein.
Those of ordinary skill in the art will better appreciate the features and aspects of such embodiments, and others, upon review of the specification.
A full and enabling disclosure of the of various embodiments, 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:
Reference will now be made in detail to present embodiments of the disclosure, one or more examples of which are illustrated in the accompanying drawings. The detailed description uses numerical and letter designations to refer to features in the drawings. Like or similar designations in the drawings and description have been used to refer to like or similar parts of the disclosure.
As used herein, the terms “first,” “second,” and “third” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components. The terms “upstream” and “downstream” refer to the relative direction with respect to fluid flow in a fluid pathway. For example, “upstream” refers to the direction from which the fluid flows, and “downstream” refers to the direction to which the fluid flows. The term “radially” refers to the relative direction that is substantially perpendicular to an axial centerline of a particular component, the term “axially” refers to the relative direction that is substantially parallel and/or coaxially aligned to an axial centerline of a particular component, and the term “circumferentially” refers to the relative direction that extends around the axial centerline of a particular component.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
Each example is provided by way of explanation, not limitation. In fact, it will be apparent to those skilled in the art that modifications and variations can be made 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 combustor for a land based power generating 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 style or type of combustor for a turbomachine and are not limited to combustors or combustion systems for land based power generating gas turbines unless specifically recited in the claims.
Referring now to the drawings,
During operation, air 20 flows into the compressor 12 where the air 20 is progressively compressed, thus providing compressed or pressurized air 22 to the combustor 14. At least a portion of the compressed air 22 is mixed with a fuel 24 within the combustor 14 and burned to produce combustion gases 26. The combustion gases 26 flow from the combustor 14 into the turbine 16, wherein energy (kinetic and/or thermal) is transferred from the combustion gases 26 to rotor blades (not shown), thus causing shaft 18 to rotate. The mechanical rotational energy may then be used for various purposes such as to power the compressor 12 and/or to generate electricity. The combustion gases 26 may then be exhausted from the gas turbine 10.
In particular embodiments, the combustion liner 36 is at last partially circumferentially surrounded by an outer sleeve 42. The outer sleeve 42 may be formed as a single component or formed by multiple sleeve segments such as by a flow sleeve 44 and an impingement sleeve 46 which is slideably engaged with the flow sleeve 44 to allow for axial relative movement therebetween. The flow sleeve 44 and the impingement sleeve 46 are radially spaced from the combustion liner 36 so as to define a cooling flow passage 48 therebetween. The impingement sleeve 46 and/or the flow sleeve 44 may define a plurality of inlets or holes (not shown) which provide for fluid communication between the cooling flow passage 48 and the high pressure plenum 30.
In various embodiments, as shown in
Each radial fuel injector 50 extends radially through the impingement sleeve 46, the cooling flow passage 48 and at least partially through the combustion liner 36. In one embodiment, at least one radial fuel injector 50 is rigidly connected to at least one of the impingement sleeve 46 and the combustion liner 36. The radial fuel injector(s) 50 provides a secondary fuel and air mixture to the secondary combustion zone 40 defined within the combustion liner 36 downstream from the fuel nozzle(s) 34 and/or the primary combustion zone 38.
In particular embodiments, as shown in
In various embodiments, as shown in
As shown in
In particular embodiments, as shown in
In particular embodiments, as shown in
In particular embodiments, the injector cover 128 includes one or more apertures 136. In operation, the aperture(s) 136 may provide for fluid communication between the high pressure plenum 30 (
In various embodiments, the first end 102 of the air shield assembly 100 may be slideably attached to the flow sleeve 44.
In particular embodiments, as shown in
In particular embodiments, a the stud 142 extends radially through a first washer or collar 146 which is disposed along an outer surface 148 of the flange 132 of the forward sleeve 126. A spring or bushing 150 such as a wave or compression spring is disposed radially between a nut 152 and the first washer 146. In particular embodiments, a second washer 154 may be disposed between the spring 150 and the nut 152.
When assembled, the nut 152 may be tightened such that the spring 150 exerts a compressive force against the first washer 146 which is transferred to the outer surface 148 of the flange 132 of the forward sleeve 126 to restrict or prevent radial movement of the first end 102 of the air shield assembly 100 but still allow for axial or sliding movement of the air shield assembly 100 across the outer surface 66 of the flow sleeve 44 when there is relative movement, for example due to thermal expansion and contraction, between the flow sleeve 44 and the impingement sleeve 46 and/or the combustion liner 44.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention 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.
