Patent Description:
Gas turbine engines are driven by a flow of combustion gases passing through the engine to rotate a multitude of turbine blades. A combustor can be provided within the gas turbine engine and is fluidly coupled with a turbine into which the combusted gases flow.

Hydrocarbon fuels are commonly used in the combustor of a gas turbine engine. Generally, air and fuel are fed separately to the combustor, until they are mixed, and the mixture is combusted to produce hot combustion gas. The combustion gas is then fed to a turbine where it rotates the turbine to produce power. By-products of the hydrocarbon fuel combustion typically include nitrogen oxide and nitrogen dioxide (collectively called NOx), carbon monoxide (CO), unburned hydrocarbon (UHC) (e.g., methane and volatile organic compounds that contribute to the formation of atmospheric ozone), and other oxides, including oxides of sulfur (e.g., SO<NUM> and SO<NUM>).

<CIT> relates to a flame tube for a gas turbine engine, including a plurality of primary combustion air inlets, a plurality of secondary combustion air inlets and a plurality of dilution air inlets and variable flow restricting means associated with at least some of the inlets for varying the ration of primary combustion air to secondary combustion air to dilution air.

Aspects of the disclosure described herein are directed to a combustor. The combustor includes a combustion chamber at least partially defined by a dome wall, a casing, an inner liner and an outer liner. A compressed air passageway is formed between the casing, the inner liner and the outer liner. A set of dilution passages extend through at least one of the inner liner or the outer liner fluidly coupling the compressed air passageway to the combustion chamber. A baffle is provided in a portion of the compressed air passage. The baffle is movable to occlude a compressed air within the compressed air passageway to at least a portion of the set of dilution passages. As used herein, the term occlude is defined as to stop, limit, or otherwise constrict a flow of air from a first passage from entering a second passage.

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

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

The term "fluid" may be a gas or a liquid. The term "fluid communication" means that a fluid is capable of making the connection between the areas specified.

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

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

Furthermore, as used herein, the term "set" or a "set" of elements can be any number of elements, including only one.

Accordingly, a value modified by a term or terms, such as "about", "approximately", "generally", and "substantially", are not to be limited to the precise value specified. For example, the approximating language may refer to being within a <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> percent margin in either individual values, range(s) of values and/or endpoints defining range(s) of values.

<FIG> is a schematic view of a gas turbine engine <NUM>. As a non-limiting example, the gas turbine engine <NUM> can be used within an aircraft. The gas turbine engine <NUM> can include, at least, a compressor section <NUM>, a combustion section <NUM>, and a turbine section <NUM> in serial flow arrangement. A drive shaft <NUM> rotationally couples the compressor and turbine sections <NUM>, <NUM>, such that rotation of one affects the rotation of the other, and defines a rotational axis or engine centerline <NUM> for the gas turbine engine <NUM>.

The compressor section <NUM> can include a low-pressure (LP) compressor <NUM>, and a high-pressure (HP) compressor <NUM> serially fluidly coupled to one another. The turbine section <NUM> can include an LP turbine <NUM>, and an HP turbine <NUM> serially fluidly coupled to one another. The drive shaft <NUM> can operatively couple the LP compressor <NUM>, the HP compressor <NUM>, the LP turbine <NUM> and the HP turbine <NUM> together. Alternatively, the drive shaft <NUM> can include an LP drive shaft (not illustrated) and an HP drive shaft (not illustrated). The LP drive shaft can couple the LP compressor <NUM> to the LP turbine <NUM>, and the HP drive shaft can couple the HP compressor <NUM> to the HP turbine <NUM>. An LP spool can be defined as the combination of the LP compressor <NUM>, the LP turbine <NUM>, and the LP drive shaft such that the rotation of the LP turbine <NUM> can apply a driving force to the LP drive shaft, which in turn can rotate the LP compressor <NUM>. An HP spool can be defined as the combination of the HP compressor <NUM>, the HP turbine <NUM>, and the HP drive shaft such that the rotation of the HP turbine <NUM> can apply a driving force to the HP drive shaft which in turn can rotate the HP compressor <NUM>.

The compressor section <NUM> can include a plurality of axially spaced stages. Each stage includes a set of circumferentially-spaced rotating blades and a set of circumferentially-spaced stationary vanes. The compressor blades for a stage of the compressor section <NUM> can be mounted to a disk, which is mounted to the drive shaft <NUM>. Each set of blades for a given stage can have its own disk. The vanes of the compressor section <NUM> can be mounted to a casing which can extend circumferentially about the gas turbine engine <NUM>. It will be appreciated that the representation of the compressor section <NUM> is merely schematic and that there can be any number of stages. Further, it is contemplated, that there can be any other number of components within the compressor section <NUM>.

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

The combustion section <NUM> can be provided serially between the compressor section <NUM> and the turbine section <NUM>. The combustion section <NUM> can be fluidly coupled to at least a portion of the compressor section <NUM> and the turbine section <NUM> such that the combustion section <NUM> at least partially fluidly couples the compressor section <NUM> to the turbine section <NUM>. As a non-limiting example, the combustion section <NUM> can be fluidly coupled to the HP compressor <NUM> at an upstream end of the combustion section <NUM> and to the HP turbine <NUM> at a downstream end of the combustion section <NUM>.

During operation of the gas turbine engine <NUM>, ambient or atmospheric air is drawn into the compressor section <NUM> via a fan (not illustrated) upstream of the compressor section <NUM>, where the air is compressed defining a pressurized air. The pressurized air can then flow into the combustion section <NUM> where the pressurized air is mixed with fuel and ignited, thereby generating combustion gases. Some work is extracted from these combustion gases by the HP turbine <NUM>, which drives the HP compressor <NUM>. The combustion gases are discharged into the LP turbine <NUM>, which extracts additional work to drive the LP compressor <NUM>, and the exhaust gas is ultimately discharged from the gas turbine engine <NUM> via an exhaust section (not illustrated) downstream of the turbine section <NUM>. The driving of the LP turbine <NUM> drives the LP spool to rotate the fan (not illustrated) and the LP compressor <NUM>. The pressurized airflow and the combustion gases can together define a working airflow that flows through the fan, compressor section <NUM>, combustion section <NUM>, and turbine section <NUM> of the gas turbine engine <NUM>.

<FIG> depicts a cross-section view of the combustion section <NUM> taken along line II-II of <FIG>. The combustion section <NUM> includes a combustor <NUM> having a set of fuel cups <NUM> disposed around a combustor centerline <NUM>. The combustor centerline <NUM> can be in-line with, offset from, parallel to, or non-parallel to the engine centerline <NUM> of the gas turbine engine <NUM> (<FIG>). The combustor centerline <NUM> can be a centerline for an entirety of the combustion section <NUM>, a single combustor, or a set of combustors that are arranged about the combustor centerline <NUM>.

The combustor <NUM> can have a can, can-annular, or annular arrangement depending on the type of engine in which the combustor <NUM> is located. In a non-limiting example, an annular arrangement is illustrated and disposed within a casing <NUM>. The combustor <NUM> is defined by a liner <NUM> including an outer liner 82a and an inner liner 82b concentric with respect to each other and annular about the combustor centerline <NUM>. The combustor <NUM> includes a dome assembly <NUM> including a dome wall <NUM>. The dome wall <NUM>, the outer liner 82a and the inner liner 82b, together, at least partially define a combustion chamber <NUM>. The combustion chamber <NUM> is annular about the combustor centerline <NUM>.

At least one fuel cup <NUM>, illustrated as multiple fuel injectors annularly arranged about the combustor centerline <NUM>, is fluidly coupled to the combustion chamber <NUM>. A compressed air passageway <NUM> can be defined at least in part by both the liner <NUM> and the casing <NUM>.

The at least one fuel cup <NUM> is included within a plurality of fuel cups <NUM>. Each fuel cup <NUM> can include a fuel cup centerline <NUM> that extends into the page. Each fuel cup centerline <NUM> can be arranged along a circumferential line <NUM>. Alternatively, one or more fuel cups <NUM> can be offset from the circumferential line <NUM>. Additionally, the fuel cups <NUM> can be arranged such that the fuel cup centerlines <NUM> form a pattern relative to, but not necessarily on, the circumferential line <NUM>.

<FIG> depicts a cross-section view taken along line III-III of <FIG> illustrating the combustion section <NUM>. The fuel cup <NUM> can be coupled to and disposed within the dome assembly <NUM>. The fuel cup <NUM> can include a flare cone <NUM> and a swirler <NUM>. The flare cone <NUM> includes an outlet <NUM> of the fuel cup <NUM> directly fluidly coupled to the combustion chamber <NUM>. The fuel cup <NUM> is fluidly coupled to a fuel inlet <NUM> via a linear passageway <NUM>.

Both the outer and inner liners 82a, 82b have an outer surface <NUM> and an inner surface <NUM>. The inner surface <NUM> at least partially defining the combustion chamber <NUM>. The liner <NUM> can be made of one continuous monolithic portion or be multiple monolithic portions assembled together to define the outer and inner liners 82a, 82b. By way of non-limiting example, the outer surface <NUM> can define a first piece of the liner <NUM> while the inner surface <NUM> can define a second piece of the liner <NUM> that when assembled together form the liner <NUM>. It is further contemplated that the liner <NUM> can be any type of liner <NUM>, including but not limited to a single wall or a double walled liner or a tile liner. An ignitor <NUM> can be provided at the liner <NUM> and fluidly coupled to the combustion chamber <NUM>, at any location.

When viewed from an axial plane extending from the combustor centerline <NUM> (<FIG>) and passing through a center point of the fuel cup <NUM>, a mean centerline <NUM>, lying in the axial plane, extends through the combustion chamber <NUM> equidistant between the inner liner 82b and the outer liner 82a. The mean centerline <NUM> can begin at or be radially offset from the fuel cup centerline <NUM> (<FIG>) at the outlet <NUM>.

The compressed air passageway <NUM> is formed between the outer surface <NUM> of the outer liner 82a and the inner liner 82b, and opposing portions of the casing <NUM>. A first set of dilution passages <NUM> can extend through the dome wall <NUM> and exhaust to the combustion chamber <NUM>. A second set of dilution passages <NUM> can extend through at least one of the inner liner 82b and the outer liner 82a. Each dilution passage of the second set of dilution passages <NUM> includes an inlet <NUM> provided on the outer surface <NUM> and a dilution hole <NUM> provided on the inner surface <NUM>. The second set of dilution passages <NUM> fluidly couple the compressed air passageway <NUM> to the combustion chamber <NUM>.

A set of baffles <NUM> is provided within a portion of the compressed air passageway <NUM> axially aligned with at least a portion of the second set of dilution passages <NUM>. Each baffle of the set of baffles <NUM> are operably coupled to an arm <NUM>. The arm <NUM> is operably coupled to an actuator <NUM>. As used herein, the actuator <NUM> can be any suitable device used to translate the arm in at least one direction. As a non-limiting example, the actuator <NUM> can be an AC or DC motor, a DC motor, a pneumatic pump, an engine, a hydraulic pump, an electromagnetic actuator, a piezoelectric motor, or an electromechanical motor. While two baffles are illustrated, it will be appreciated that the set of baffles <NUM> can include any number of one or more baffles. Further, while illustrated as being provided radially outward from both of the inner liner 82b and the outer liner 82a, with respect to the mean centerline <NUM>, it will be appreciated that the set of baffles <NUM> can be provided radially outward from a single liner of the inner liner 82b or the outer liner 82a.

During operation, a compressed airflow (C) can flow from the compressor section <NUM> (<FIG>) to the combustor <NUM> through the dome assembly <NUM>. The compressed airflow (C) is fed to the fuel cup <NUM> via the swirler <NUM> as a swirler airflow (S). A flow of fuel (F) is fed to the fuel cup <NUM> via the fuel inlet <NUM> and the linear passageway <NUM>. The swirler airflow (S) and the flow of fuel (F) are mixed at the flare cone <NUM> and fed to the combustion chamber <NUM> as a fuel/air mixture. The ignitor <NUM> can ignite the fuel/air mixture to define a flame within the combustion chamber <NUM>, which generates a combustion gas (G). While shown as starting axially downstream of the outlet <NUM>, it will be appreciated that the fuel/air mixture can be ignited at or near the outlet <NUM>.

The compressed airflow (C) is further fed to the first set of dilution passages <NUM> as a first dilution airflow (D1) and through the compressed air passageway <NUM> to the second set of dilution passages <NUM> as a second dilution airflow (D2). The first dilution airflow (D1) is used to direct and shape a flame, while the second dilution airflow (D2) is used to further shape and direct the combustion gas (G) or the flame. It is contemplated that the compressed airflow (C) fed through the second set of dilution passages <NUM> can make up greater than or equal to <NUM>% and less than or equal to <NUM>% of the total compressed airflow (C) that is fed to the combustor <NUM>. As a non-limiting example, the compressed airflow (C) fed through the second set of dilution passages <NUM> can make up greater than or equal to <NUM>% and less than or equal to <NUM>% of the total compressed airflow (C) that is fed to the combustor <NUM>.

At least a portion of the compressed airflow (C) in the compressed air passageway <NUM> can continue past the second set of dilution passages <NUM> and to downstream portions of the gas turbine engine <NUM> (<FIG>) to define a bypass compressed airflow (Cb). The bypass compressed airflow (Cb) can be used for any suitable purpose such as, but not limited to, cooling.

<FIG> is a schematic side cross-sectional view of the baffle <NUM> taken along line IV-IV of <FIG>. The baffle <NUM>, as described herein, is provided within the compressed air passageway <NUM> confronting the liner <NUM>. It will be appreciated that the liner <NUM> can be any one of the outer liner 82a (<FIG>) or the inner liner 82b (<FIG>). Further, the second set of dilution passages <NUM> will hereinafter be referred to as the set of dilution passages <NUM>.

The baffle <NUM> axially overlies at least a portion of the dilution passage <NUM>. As a non-limiting example, the baffle <NUM> axially overlies the inlet <NUM> of the dilution passage <NUM>. The baffle <NUM> is movable, via the arm <NUM>. The baffle <NUM> has a range of movement that has a degree of freedom in at least one of the radial direction or an axial direction. As a non-limiting example, the degree of freedom of the baffle <NUM> is along a radial plane of movement <NUM>.

The baffle <NUM>, as illustrated, is in a first position where the second dilution airflow (D2) is free to flow into the dilution passage <NUM> through the inlet <NUM>. The baffle <NUM> can be moved along the radial plane of movement <NUM> a maximum radial distance from the outer surface <NUM> of the liner <NUM>. As a non-limiting example, the maximum radial distance can be an instance where the baffle <NUM> confronts and contacts a respective portion of the casing <NUM> (<FIG>). The baffle <NUM> can further be sized such that it sits flush against a respective portion the liner <NUM> or the casing <NUM>.

<FIG> is a schematic side cross-sectional view of the baffle <NUM> of <FIG> in a second position. The baffle <NUM>, as illustrated, is in the second position where the second dilution airflow (D2) is impeded or otherwise stopped from flowing into the dilution passage <NUM>. The baffle <NUM> is moveable between the first position (<FIG>) and the second position to effectively occlude the compressed airflow (C) from the inlet <NUM> of the dilution passage <NUM>. It will be appreciated that in the first position, the compressed airflow (C) is fully occluded and when the baffle <NUM> is in the second position, the compressed airflow |(C) can be less than <NUM>% and greater than or equal to <NUM>% occluded. When the baffle <NUM> partially or fully occludes the compressed airflow (C) from the dilution passage <NUM>, the compressed airflow (C) that would flow into the dilution passage <NUM> if the dilution passage <NUM> were not occluded can instead flow to a downstream portion of the gas turbine engine (<FIG>) as the bypass compressed airflow (Cb). In other words, the positioning of the baffle <NUM> can be used to tailor the amount of the second dilution airflow (D2) and the bypass compressed airflow (Cb) that flows through the combustor <NUM> (<FIG>).

It is contemplated that the positioning of the baffle <NUM> can further be used to tailor at least one flow characteristic of the second dilution airflow (D2). As a non-limiting example, the baffle <NUM> can be positioned with respect to the inlet <NUM> such that the baffle <NUM> acts as a nozzle for the second dilution airflow (D2) being fed to the inlet <NUM>. When acting as a nozzle, the baffle <NUM> can accelerate and pressurize the second dilution airflow (D2).

The control of the amount and the flow characteristics of the second dilution airflow (D2) flowing through the dilution passage <NUM> by the baffle <NUM> can be used for flame-shaping purposes. During operation of the combustor <NUM>, an ignited mixture of fuel (F) and the first dilution airflow (D1) can generate a flame or otherwise the combustion gases (G). The second dilution airflow (D2) is used to affect how the flame or the combustion gases flow through the combustion chamber <NUM>. As a non-limiting example, a faster and larger volume of the second dilution airflow (D2) can be used to penetrate into the combustion chamber <NUM> and effectively reduce the footprint of the flame or the combustion gases (G) within the combustion chamber <NUM>. Conversely, if the baffle <NUM> is moved to close off the inlet <NUM> such that no second dilution airflow (D2) flows into the combustion chamber <NUM>, the flame or the combustion gases (G) will have more room to expand and thus have a larger footprint.

The shaping of the flame or the combustion gases (G) is hereinafter referred to as flame shaping. It is contemplated that flame shaping through the presence or non-presence of the second dilution airflow (D2) by the selective movement of the baffle <NUM> can be used to tailor the footprint or profile of the flame within the combustion chamber <NUM>. The flame shaping can further be used to tailor a temperature distribution at the outlet of the combustion chamber <NUM>. As a non-limiting example, a uniform temperature distribution at the outlet can ensure that the gas turbine engine <NUM> is uniformly thermally loaded downstream of the combustion section <NUM>, thus increasing the efficiency and lifespan of the gas turbine engine <NUM> (<FIG>).

The positioning of the baffle <NUM> can further be dependent on the operational state of the gas turbine engine <NUM> (<FIG>). For example, it has been found that during a relight condition (e.g., during initial ignition or restart ignition of the fuel/air mixture exiting the fuel cup <NUM> of <FIG>), the baffle <NUM> can fully or partially cover the set of dilution passages <NUM> such that a maximum amount of compressed air (C) (<FIG>) flows into the combustion chamber <NUM> as the first dilution airflow (D1), into the swirler <NUM> as the swirler airflow (S) or otherwise to a downstream portion of the gas turbine engine <NUM> as the bypass compressed airflow (Cb). It has been found that maximizing, for example, the swirler airflow (S) and the first dilution airflow (D1) can help with initial flame propagation and shaping to ensure proper ignition of the gas turbine engine <NUM>. Further, maximizing the amount of compressed air (C) being fed to the swirler <NUM> by closing the baffle <NUM>, increases the flow through the swirler <NUM> which increases the pressure drop across the swirler <NUM> and a velocity of the flow exiting the swirler <NUM> at the outlet <NUM>. Once ignited, it may be desirable to have further flame shaping through use of the set of dilution passages <NUM>. As such, the baffle <NUM> can be moved to partially uncover or fully uncover the inlets <NUM>, thus allowing the second dilution airflow (D2) to flow into the combustion chamber <NUM>.

The combustor <NUM> shown of <FIG> is well suited for the use of a hydrogen-containing gas as the fuel because it helps contain the faster moving flame front associated with hydrogen fuel, as compared to traditional hydrocarbon fuels. However, the combustor <NUM> can be used with traditional hydrocarbon fuels.

It has been found that use of the baffle <NUM> is especially advantageous in instances where the fuel used in the combustion section <NUM> is a hydrogen-containing fuel. Hydrogen-containing fuel has a higher calorific value than conventional fuels (e.g., fuels using carbons), thus the flame or combustion gases (G) generated with hydrogen-containing fuels is hotter than a flame or combustion gases that are generated with conventional fuels. As such, directing the flame away from various portions of the combustion section <NUM> (e.g., the inner liner 82b and the outer liner 82a) through the second dilution airflow (D2) ensures that the heat from the flame does not damage portions of the combustion section <NUM> that cannot withstand the heat of the flame. Further, the flame generated by the hydrogen-containing fuel has a higher velocity than a flame generated by a conventional fuel. The higher velocity, in turn, means that the flame tends to want to keep its shape, which can result in a non-uniform flame and temperature distribution at the outlet of the combustor <NUM>. The baffle <NUM> is used to ensure that the flames or combustion gases (G) have a uniform temperature and flame distribution at the outlet of the combustion chamber <NUM>.

With reference to the relight condition (e.g., closing the baffle <NUM>), increasing the velocity of the flow exiting the outlet <NUM> of the fuel cup <NUM> is especially advantageous when using hydrogen as a fuel. It has been found that the increase in the velocity of the hydrogen fuel and air mixture at the outlet <NUM>, in turn, reduces chances of flashback and flame holding on the fuel cup <NUM> and the dome wall <NUM>.

<FIG> is a schematic transverse cross-sectional view of the combustor <NUM> taken along line VI-VI of <FIG>. The set of baffles <NUM> can extend circumferentially continuously about or be circumferentially segmented about the mean centerline <NUM> (<FIG>) or the combustor centerline <NUM>.

The set of baffles <NUM> can include two or more circumferentially adjacent baffles <NUM>. Each baffle of the two or more circumferentially adjacent baffles <NUM> can be independently movable via a respective arm <NUM> and further overlay a respective portion of the set of dilution passages <NUM>. Each arm <NUM> can be coupled to a respective actuator <NUM> (<FIG>) or to a single common actuator <NUM>.

Each baffle of the two or more circumferentially adjacent baffles <NUM> can further correspond to any number of one or more fuel cups <NUM>. As a non-limiting example, each baffle of the two or more circumferentially adjacent baffles <NUM> can extend circumferentially across two respective fuel cups <NUM>.

The independent movement of the baffles of the two or more circumferentially adjacent baffles <NUM> allows for further flame shaping by controlling the location where the second dilution airflow (D2) (<FIG>) flows into the combustion chamber <NUM>.

<FIG> is a schematic side cross-sectional view of an exemplary baffle <NUM> provided within a combustor <NUM> suitable for use within the combustor <NUM> of <FIG>. The combustor <NUM> is similar to the combustor <NUM>, therefore, like parts will be identified by like numerals increased to the <NUM> series with it being understood that the description of the combustor <NUM> applies to the combustor <NUM> unless noted otherwise.

The combustor <NUM> includes a liner <NUM> with an outer surface <NUM> and an inner surface <NUM>. A dilution passage <NUM> extends through the liner <NUM> between an inlet <NUM> provided on the outer surface <NUM> and a dilution hole <NUM> provided on the inner surface <NUM>. The inner surface <NUM> confronts and at least partially defines a combustion chamber <NUM>. A mean centerline <NUM> extends through the combustion chamber <NUM>. The outer surface <NUM> at least partially defines a compressed air passageway <NUM>. The baffle <NUM> is provided within a portion of the compressed air passageway <NUM>. The baffle <NUM> is movable within the compressed air passageway <NUM> via an arm <NUM>.

The baffle <NUM> is similar to the baffle <NUM> (<FIG>), as the baffle <NUM> occludes the second dilution airflow (D2) (<FIG>) from the inlet <NUM> of the dilution passage <NUM>. The baffle <NUM>, however, has a range of movement that has a degree of freedom in at least one of the radial direction or an axial direction. As a non-limiting example, the degree of freedom of the baffle <NUM> is along an axial plane of movement <NUM> rather than the radial plane of movement <NUM> (<FIG>). It is contemplated that the baffle <NUM>, therefore, can be slidably moved over the inlet <NUM> to fully cover, partially cover, or fully uncover the inlet <NUM>. In the instance where the inlet <NUM> is partially covered, the baffle <NUM> acts as a nozzle for the compressed airflow (C) (<FIG>) flowing into the inlet <NUM>.

It is contemplated that the set of dilution passages <NUM> can include any number of one or more axially downstream dilution passages <NUM>. The baffle <NUM> can be sized to partially cover, fully cover, or fully uncover the one or more axially downstream dilution passages <NUM>. The baffle <NUM> is movable such that the axially downstream dilution passages <NUM> and the axially upstream dilution passages have varying degrees of occlusion. It will be appreciated that the baffle <NUM> can be sized such that the baffle <NUM> can simultaneously fully cover, partially cover, or fully uncover all dilution passages of the set of dilution passages <NUM> including the one or more axially downstream dilution passages <NUM>.

The selective occlusion of the compressed airflow to the set of dilution passages <NUM> optionally including the axially downstream dilution passage <NUM> can be used to further tailor the flame shaping. As a non-limiting example, fully uncovering or partially uncovering the axially downstream dilution passages <NUM> can be used to further shape the flame or combustion gases (G) downstream of the axially forward dilution passages of the set of dilution passages <NUM>.

As a non-limiting example, blocking the upstream dilution passages <NUM> and allowing the second dilution airflow (D2) to flow through the axially downstream dilution passage <NUM> can allow for the flame or combustion gases (G) to further expand radially outward from the mean centerline <NUM>, hereinafter referred to as an increase in flame volume. The increase in flame volume, in turn, achieves better flame stability. It is contemplated that opening the axially downstream dilution passages <NUM>, during relight, can allow for a more stable flame and thus increase the efficiency of the combustor <NUM> during startup of the combustor <NUM>. It has been further found that varying the occlusion of the set of dilution passages <NUM> and the set of axially downstream dilution passages <NUM> can further limit the amount of emissions generated by the combustion process.

<FIG> is a schematic side cross-sectional view of an exemplary baffle <NUM> provided within a combustor <NUM> suitable for use within the combustor <NUM> of <FIG>. The combustor <NUM> is similar to the combustor <NUM>, <NUM>, therefore, like parts will be identified by like numerals increased to the <NUM> series with it being understood that the description of the combustor <NUM>, <NUM> applies to the combustor <NUM> unless noted otherwise.

The combustor <NUM> includes a liner <NUM> with an outer surface <NUM> and an inner surface <NUM>. A dilution passage <NUM> extends through the liner <NUM> between an inlet <NUM> provided on the outer surface <NUM> and a dilution hole <NUM> provided on the inner surface <NUM>. The inner surface <NUM> confronts and at least partially defines a combustion chamber <NUM>. A mean centerline <NUM> extends through the combustion chamber <NUM>. The outer surface <NUM> at least partially defines a compressed air passageway <NUM>. The baffle <NUM> is provided within a portion of the compressed air passageway <NUM>. The baffle <NUM> is movable within the compressed air passageway <NUM> via an arm <NUM>. The baffle <NUM> has a range of movement that has a degree of freedom in at least one of the radial direction or an axial direction.

The baffle <NUM> is similar to the baffle <NUM>, <NUM> as the baffle <NUM> occludes the second dilution airflow (D2) (<FIG>) from the inlet <NUM> of the dilution passage <NUM>. The baffle <NUM>, however, includes a major body axis <NUM> extending at a radial baffle angle <NUM> with respect to a projection <NUM> of the mean centerline <NUM>. In other words, the baffle <NUM> is radially inclined with respect to the mean centerline <NUM>. The radial baffle angle <NUM> can be any suitable size. As a non-limiting example, the radial baffle angle <NUM> can have an absolute value of greater than or equal to <NUM> degrees and less than or equal to <NUM> degrees.

The inclination of the baffle <NUM> is used to funnel the compressed airflow (C) into the inlet <NUM>. The inclination of the baffle <NUM> can further be used as a nozzle to accelerate and pressurize the compressed airflow (C) prior to it entering the inlet <NUM>.

<FIG> is a schematic top-down view of an exemplary baffle <NUM> provided within a combustor <NUM> suitable for use within the combustor <NUM> of <FIG>. The combustor <NUM> is similar to the combustor <NUM>, <NUM>, <NUM>, therefore, like parts will be identified by like numerals increased to the <NUM> series with it being understood that the description of the combustor <NUM>, <NUM>, <NUM> applies to the combustor <NUM> unless noted otherwise.

The combustor <NUM> includes a liner <NUM> with an outer surface <NUM>. A dilution passage <NUM> extends through the liner <NUM> from an inlet <NUM> provided on the outer surface <NUM>. The liner <NUM> confronts and at least partially defines a combustion chamber (not illustrated, e.g., the combustion chamber <NUM> of <FIG>). A mean centerline, illustrated as a projection <NUM>, extends through the combustion chamber. The outer surface <NUM> at least partially defines a compressed air passageway <NUM>. The baffle <NUM> is provided within a portion of the compressed air passageway <NUM>. The baffle <NUM> is movable within the compressed air passageway <NUM> via an arm <NUM>. The baffle <NUM> has a range of movement that has a degree of freedom in at least one of the radial direction or an axial direction.

The baffle <NUM> is similar to the baffle <NUM>, <NUM>, <NUM> in that the baffle <NUM> occludes a compressed airflow (e.g., the compressed airflow (C) of <FIG>) from the inlet <NUM>. The baffle <NUM>, however, includes a major body axis <NUM> forming a circumferential baffle angle <NUM> with respect to the projection <NUM> of the mean centerline. The circumferential baffle angle <NUM> can be any suitable angle. As a non-limiting example, the circumferential baffle angle <NUM> can have an absolute value of greater than or equal to <NUM> degrees and less than or equal to <NUM> degrees. As a non-limiting example, the circumferential baffle angle can have an absolute value of less than <NUM> degrees.

The set of dilution passages <NUM> include a series of axially spaced dilutions passages. Each dilution passage of the set of dilution passages <NUM> includes a dilution passage centerline (e.g., the dilution passage centerline <NUM> of <FIG>) that intersects the inlet <NUM> at a center point <NUM>. The set of dilution passages <NUM> can be provided along a line <NUM> that extends between each consecutive center point <NUM> of the set of dilution passages <NUM>. The major body axis <NUM> can correspond to or otherwise be parallel to the line <NUM>. As such, the baffle <NUM> can be moved to cover, partially uncover, or fully uncover all dilution passages of the set of dilution passages <NUM> at once. It will be appreciated that the line <NUM>, and therefore the major body axis <NUM>, can be linear or non-linear. As such, it will be appreciated that the baffle <NUM> can be curved or non-curved.

<FIG> is a schematic top-down view of an exemplary baffle <NUM> provided within a combustor <NUM> suitable for use within the combustor <NUM> of <FIG>. The combustor <NUM> is similar to the combustor <NUM>, <NUM>, <NUM>, <NUM>, therefore, like parts will be identified by like numerals increased to the <NUM> series with it being understood that the description of the combustor <NUM>, <NUM>, <NUM>, <NUM> applies to the combustor <NUM> unless noted otherwise.

The combustor <NUM> includes a liner <NUM> with an outer surface <NUM>. A dilution passage <NUM> extends through the liner <NUM> from an inlet <NUM> provided on the outer surface. The liner <NUM> confronts and at least partially defines a combustion chamber (not illustrated, e.g., the combustion chamber <NUM> of <FIG>). A mean centerline, illustrated as a projection <NUM>, extends through the combustion chamber. The outer surface <NUM> at least partially defines a compressed air passageway <NUM>. The baffle <NUM> is provided within a portion of the compressed air passageway <NUM>. The baffle <NUM> is movable within the compressed air passageway <NUM> via an arm <NUM>. The baffle <NUM> has a range of movement that has a degree of freedom in at least one of the radial direction or an axial direction.

The baffle <NUM> is similar to the baffle <NUM> in that it includes a major body axis <NUM> that forms a circumferential baffle angle <NUM> with respect to the projection <NUM>. The difference, however, is that the set of dilution passages <NUM> are circumferentially spaced along a line <NUM> that is perpendicular to the projection <NUM>, and extends through a center point <NUM> of each dilution passage <NUM>. The major body axis <NUM> is non-parallel to the line <NUM>. As such, the amount of occlusion is non-constant between circumferentially adjacent dilution passages when the baffle <NUM> is moved over a respective dilution passage <NUM>.

The baffle <NUM> can further be movable, via the arm <NUM>, about a rotational axis (Rax). In other words, the size of the circumferential baffle angle <NUM> can be varied by rotating the baffle <NUM> about the rotational axis (Rax).

During operation the baffle <NUM> can be used to selectively fully occlude, partially occlude or not occlude (e.g., fully open) at least one of the dilution passages of the set of dilution passages <NUM> that are in a circumferential row. As a non-limiting example, the baffle <NUM> can fully occlude a first dilution passage while leaving a second dilution passage, circumferentially adjacent the first dilution passage not occluded or partially occluded. It is contemplated that providing differing amounts of occlusion along the set of dilution passages <NUM> arranged in the circumferential row can allow for increased temperature control of the flame or combustion gases (G) within the combustion chamber. As a non-limiting example, if a higher flame temperature is measured or expected to be present around the second dilution passage rather than the first dilution passage, the baffle <NUM> can be moved to direct compressed air through the second dilution passage to effectively push away from the liner <NUM> or otherwise cool the hot portions of the flame. The cooling of the hotter regions of the flame, in turns, results in a uniform temperature distribution at the outlet of the combustor <NUM>. This ultimately reduces the emissions and achieves a better flame profile at the outlet of the combustor <NUM>.

In instances where the baffle <NUM> is movable about the rotational axis (Rax), the circumferential baffle angle <NUM> can be varied to change the degree of occlusion of each dilution passage of the set of dilution passages <NUM>. As a non-limiting example, if it is desired to cover all dilution passages of the set of dilution passages <NUM>, the arm <NUM> can move the baffle <NUM> such that the major body axis <NUM> is parallel to the line <NUM>.

<FIG> is a schematic side cross-sectional view of an exemplary baffle <NUM> provided within a combustor <NUM> according to the invention, suitable for use within the combustor <NUM> of <FIG>. The combustor <NUM> is similar to the combustor <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, therefore, like parts will be identified by like numerals increased to the <NUM> series with it being understood that the description of the combustor <NUM>, <NUM>, <NUM>, <NUM>, <NUM> applies to the combustor <NUM> unless noted otherwise.

The combustor <NUM> includes a casing <NUM> and a liner <NUM> with an outer surface <NUM> and an inner surface <NUM>. A dilution passage <NUM> extends through the liner <NUM> between an inlet <NUM> provided on the outer surface <NUM> and a dilution hole <NUM> provided on the inner surface <NUM>. The inner surface <NUM> confronts and at least partially defines a combustion chamber <NUM>. A mean centerline <NUM> extends through the combustion chamber <NUM>. The outer surface <NUM> at least partially defines a compressed air passageway <NUM>. The baffle <NUM> is provided within a portion of the compressed air passageway <NUM>. The baffle <NUM> is movable within the compressed air passageway <NUM> via an arm <NUM>.

The combustor <NUM> is similar to the combustor <NUM>, <NUM>, <NUM>, <NUM>, <NUM> in that it includes the compressed air passageway <NUM> at least partially defined within a radial space between the outer surface <NUM> and the casing <NUM>. The difference, however, is that the compressed air passageway <NUM> includes a first channel <NUM> and a second channel <NUM> split by a wall <NUM> extending through the compressed air passageway <NUM>. The wall <NUM> can start along any suitable axial location of the compressed air passageway <NUM> that is at least upstream of an axially forwardmost inlet <NUM> of the set of dilution passages <NUM>. It is further contemplated that the wall <NUM> can join with the liner <NUM> downstream of the set of dilution passages <NUM> or that the first channel <NUM> and the second channel <NUM> can merge downstream of the set of dilution passages <NUM>.

The inlet <NUM> can be fluidly coupled to the first channel <NUM> while the second channel <NUM> can be fluidly coupled to any suitable downstream portion of the gas turbine engine <NUM> (<FIG>). A static arm <NUM> can operably couple to baffle <NUM> to the casing <NUM>.

The baffle <NUM> is statically mounted to the static arm <NUM> and slidably coupled to the arm <NUM>. As such, when the arm <NUM> is moved, the baffle <NUM> rotates about the static arm <NUM> to allow for the selective occlusion of the compressed air flow into the first channel <NUM>.

As illustrated, the baffle <NUM> is in a first position where the first channel <NUM> and the second channel <NUM> are each open. As such, the compressed airflow (C) (<FIG>) can flow into the first channel <NUM> and thus the inlet <NUM> as the second dilution airflow (D2) and into the second channel <NUM> as the bypass compressed airflow (Cb). The baffle <NUM> can at least partially occlude the compressed airflow (C) to the inlet <NUM>. When partially occluding the first channel <NUM>, the baffle <NUM> can act as a nozzle.

It is contemplated that the first channel <NUM> and the second channel <NUM> can be switched such that the first channel <NUM> is the second channel <NUM> and vice-versa. When the first channel <NUM> is provided radially outward from the second channel <NUM>, with respect to the mean centerline <NUM>, a dilution channel <NUM> (illustrated in phantom lines) can extend through the wall <NUM>, the second channel <NUM> and to the dilution passage <NUM>. In such a case, the dilution channel <NUM> is defined as a portion of the dilution passage <NUM> and the inlet <NUM> is provided on a portion of the wall <NUM> confronting the first channel <NUM>. The dilution channel <NUM> can extend through a portion of the second channel <NUM>. In such a configuration, the baffle <NUM> is used to occlude the compressed airflow (C) from the second channel <NUM> rather than the first channel <NUM>.

<FIG> is a schematic side cross-sectional view of the baffle <NUM> of <FIG>. As illustrated, the baffle <NUM> is in a second position where the first channel <NUM> and thus the inlet <NUM> is fully occluded from the compressed airflow (C) (<FIG>). As such, the compressed airflow (C) flows entirely through the second channel <NUM> as the bypass compressed airflow (Cb).

<FIG> is a schematic side cross-sectional view of an exemplary baffle <NUM> provided within a combustor <NUM> according to the invention, suitable for use within the combustor <NUM> of <FIG>. The combustor <NUM> is similar to the combustor <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, therefore, like parts will be identified by like numerals increased to the <NUM> series with it being understood that the description of the combustor <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> applies to the combustor <NUM> unless noted otherwise.

The combustor <NUM> is similar to combustor <NUM> in that it includes the compressed air passageway <NUM> including a first channel <NUM> and a second channel <NUM> split by a wall <NUM> extending through the compressed air passageway <NUM>. The difference, however, is that the baffle <NUM> is pivotable about a static arm <NUM> to fully uncover, partially cover, or fully cover both of the first channel <NUM> and the second channel <NUM>. In other words, the baffle <NUM> is movable to fully cover or partially cover the first channel <NUM>, leaving the second channel <NUM> fully uncovered and vice-versa. The baffle <NUM> allows for the selective fluid coupling of the compressed airflow (C) (<FIG>) to one of or both of the first channel <NUM> and the second channel <NUM>. The baffle <NUM> has a range of movement in both the radial direction and the axial direction.

<FIG> is a schematic side cross-sectional view an exemplary set of baffles <NUM> provided within a combustor <NUM> according to the invention, suitable for use within the combustor <NUM> of <FIG>. The combustor <NUM> is similar to the combustor <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, therefore, like parts will be identified by like numerals increased to the <NUM> series with it being understood that the description of the combustor <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> applies to the combustor <NUM> unless noted otherwise.

The combustor <NUM> includes a casing <NUM>, an outer liner 882a and an inner liner 882b each with an outer surface <NUM> and an inner surface <NUM>. A dilution passage <NUM> extends through the outer and inner liners 882a, 882b between an inlet <NUM> provided on the outer surface <NUM> and a dilution hole <NUM> provided on the inner surface <NUM>. The inner surface <NUM> confronts and at least partially defines a combustion chamber <NUM>. A mean centerline <NUM> extends through the combustion chamber <NUM>. The outer surface <NUM> at least partially defines a compressed air passageway <NUM>. The set of baffles <NUM> are provided within respective portions of the compressed air passageway <NUM>. Each baffle <NUM> of the set of baffles <NUM> is movable within the compressed air passageway <NUM> via an arm <NUM>.

The combustor <NUM> is similar to the combustor <NUM>, <NUM> in that the compressed air passageway <NUM> is split into a first channel <NUM> and a second channel <NUM> via a wall <NUM>. The combustor <NUM> further includes at least two baffles <NUM>; one baffle provided in a portion of the compressed air passageway <NUM> confronting the outer liner 882a and another baffle provided in a portion of the compressed air passageway <NUM> confronting the inner liner 882b. The first channel <NUM> can be provided radially outward from or radially inward from the second channel <NUM>, with respect to the mean centerline <NUM>.

The set of baffles <NUM> are operably coupled to a respective static arm <NUM>. As illustrated, at least two baffles of the set of baffles <NUM> are operably coupled to a single static arm <NUM> and pivotable about the single static arm <NUM> via the movement of a single arm <NUM>. The baffle <NUM> has a range of movement in both the radial direction and the axial direction. The static arm <NUM> can extend from opposing portions of a casing <NUM> or otherwise extend from one portion of the casing <NUM> and be directly coupled to a radially farthest baffle of the set of baffles <NUM>. In either case, the static arm <NUM> can extend through or around the combustion chamber <NUM>. Alternatively, the static arm <NUM> can be provided axially forward of the combustion chamber <NUM> and extend through a portion of the compressed air passageway <NUM>.

As the at least two baffles of the set of baffles <NUM> are coupled to the same arm <NUM>, the at least two baffles of the set of baffles <NUM> are dependently movable with respect to one another.

At least a portion of the combustor <NUM> can be non-symmetric about the mean centerline <NUM>. As a non-limiting example, the first channel <NUM> and the second channel <NUM> radially nearest the outer liner 882a can be non-symmetric with respect to the first channel <NUM> and the second channel <NUM> provided radially nearest the inner liner 882b. In such a case, one of the first channel <NUM> would be radially outward from the second channel <NUM> such that a dilution channel <NUM> can be provided to interconnect the first channel <NUM> with a remainder of the dilution passage <NUM>. Further, in such a case, the baffles <NUM> are non-symmetric about the mean centerline <NUM>. Alternatively, the baffles <NUM>, the first channel <NUM>, and the second channel <NUM> can be symmetric about the mean centerline <NUM>.

The benefit of utilizing the illustrated configuration where at least two baffles <NUM> are controlled by a single arm <NUM> is that the number of needed actuators (e.g., the actuator <NUM> of <FIG>) is reduced. In other words, a single actuator can be used to move two or more baffles <NUM>.

<FIG> is a schematic side cross-sectional view an exemplary set of baffles <NUM> provided within a combustor <NUM> according to the invention, suitable for use within the combustor <NUM> of <FIG>. The combustor <NUM> is similar to the combustor <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, therefore, like parts will be identified by like numerals increased to the <NUM> series with it being understood that the description of the combustor <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> applies to the combustor <NUM> unless noted otherwise.

The combustor <NUM> includes a casing <NUM> an outer liner 982a and an inner liner 982b each with an outer surface <NUM> and an inner surface <NUM>. A dilution passage <NUM> extends through the outer and inner liners 982a, 982b between an inlet <NUM> provided on the outer surface <NUM> and a dilution hole <NUM> provided on the inner surface <NUM>. The inner surface <NUM> confronts and at least partially defines a combustion chamber <NUM>. A mean centerline <NUM> extends through the combustion chamber <NUM>. The outer surface <NUM> at least partially defines a compressed air passageway <NUM>. The set of baffles <NUM> are provided within respective portions of the compressed air passageway <NUM>. Each baffle <NUM> of the set of baffles <NUM> is movable within the compressed air passageway <NUM> via an arm <NUM>.

The combustor <NUM> is similar to the combustor <NUM>, <NUM>, <NUM> in that the compressed air passageway <NUM> is split into a first channel <NUM> and a second channel <NUM> via a wall <NUM>. The combustor <NUM> is similar to the combustor <NUM> in that it includes a single static arm <NUM> operably coupling two or more baffles <NUM> to the casing <NUM>. The combustor <NUM>, however, includes two independently movable baffles <NUM> coupled to the same static arm <NUM>. In other words, each baffle <NUM> includes a respective arm <NUM> coupled to a respective actuator (not illustrated, e.g., actuator <NUM> of <FIG>). Further, the set of baffles <NUM>, the arms <NUM>, the static arm <NUM>, the first channel <NUM> and the second channel <NUM> can by symmetric about the mean centerline <NUM>.

<FIG> is a schematic side cross-sectional view an exemplary set of baffles <NUM> provided within a combustor <NUM> suitable for use within the combustor <NUM> of <FIG>. The combustor <NUM> is similar to the combustor <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, therefore, like parts will be identified by like numerals increased to the <NUM> series with it being understood that the description of the combustor <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> applies to the combustor <NUM> unless noted otherwise.

The combustor <NUM> includes a casing <NUM>, an outer liner 1082a and an inner liner 1082b. The combustor <NUM> is defined by a combustor centerline <NUM>. A dilution passage <NUM> extends through the outer and inner liners 1082a, 1082b between an inlet <NUM> and a dilution hole <NUM>. The inner liner 1082b and the outer liner 1082a at least partially define a combustion chamber <NUM>. A mean centerline <NUM> extends through the combustion chamber <NUM>. A compressed air passageway <NUM> extends around the inner liner 1082b and the outer liner 1082a. The set of baffles <NUM> are provided within respective portions of the compressed air passageway <NUM>. Each baffle <NUM> of the set of baffles <NUM> is movable within the compressed air passageway <NUM> via an arm <NUM> coupled to an actuator <NUM>.

The combustor <NUM> is similar to the combustor <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> in that it includes a fuel cup <NUM> that exhausts a flame or fuel/air mixture into the combustion chamber <NUM>. The combustor <NUM>, however, includes the mean centerline <NUM> that turns upwardly (e.g.. , radially) away from the combustor centerline <NUM>.

Each baffle of the set of baffles <NUM> can be radially or axially moveable with respect to the mean centerline <NUM>. It will be appreciated that the set of baffles <NUM> can be provide along a portion of the combustor <NUM> where the mean centerline <NUM> is non-parallel to the combustor centerline <NUM>. When radially movable with respect to the mean centerline <NUM>, each radially movable baffle of the set of baffles <NUM> is axially movable with respect to the combustor centerline <NUM>. When axially movable with respect to the mean centerline <NUM>, each axially movable baffle of the set of baffles <NUM> is radially movable with respect to the combustor centerline <NUM>.

It will be appreciated that the set of baffles <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> can be applied to any suitable combustor.

<FIG> is a schematic transverse cross-sectional view of an exemplary combustor <NUM> suitable for use as the combustor <NUM> of <FIG>. The combustor <NUM> is similar to the combustor <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, therefore, like parts will be identified by like numerals increased to the <NUM> series with it being understood that the description of the combustor <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> applies to the combustor <NUM> unless noted otherwise.

The combustor <NUM> includes a casing <NUM>, an outer liner 1182a and an inner liner 1182b. The combustor <NUM> is defined by a combustor centerline <NUM>. A dilution passage <NUM> extends through the outer and inner liners 1182a between an inlet <NUM> and a dilution hole <NUM>. The inner liner 1182b and the outer liner 1182a at least partially define a combustion chamber <NUM>. A mean centerline <NUM> extends through the combustion chamber <NUM>. A compressed air passageway <NUM> extends around the inner liner 1182b and the outer liner 1182a. A set of fuel cups <NUM> exhaust into the combustion chamber <NUM>.

A set of baffles <NUM> are provided within the compressed air passageway <NUM> to occlude a flow of compressed air (C) (<FIG>) from a respective portion of the set of dilution passages <NUM>. The set of baffles <NUM> include at least two circumferentially opposing baffles that are coupled to a single arm <NUM> at circumferentially opposing ends of the single arm <NUM>. The opposing baffles of the set of baffles <NUM> can be provided at a first radial height (Rh1) and a second radial height (Rh2), respectively, from the mean centerline <NUM>. The first radial height (Rh1) can be smaller than the second radial height (Rh2) such that when a portion of the dilution passages of the set of dilution passages are fully covered by the baffle at the first radial height (Rh1), another portion of the dilution passages of the set of dilution passages <NUM> are partially covered or fully uncovered by the baffle at the second radial height (Rh2). Alternatively, the first radial height (Rh1) and the second radial height (Rh2) can be equal. The set of baffles <NUM> have a range of movement that has a degree of freedom in at least one of the radial direction or an axial direction.

Benefits of the present disclosure include a combustor suitable for use with a hydrogen-containing fuel. As outlined previously, hydrogen-containing fuels have a higher flame temperature and velocity than traditional fuels (e.g., fuels not containing hydrogen). That is, hydrogen or a hydrogen mixed fuel typically has a wider flammable range and a faster burning velocity than traditional fuels such petroleum-based fuels, or petroleum and synthetic fuel blends. These high burn temperatures of hydrogen-containing fuel mean that additional insulation is needed between the ignited hydrogen-containing fuel and surrounding components of the gas turbine engine (e.g., the inner/outer liner, and other parts of the gas turbine engine). The combustor, as described herein, includes the baffle that can fully or at least partially occlude the second dilution airflow to the combustion chamber. This, in turn, is used for flame shaping purposes, as described herein. As a non-limiting example, the control of the second dilution airflow can direct the flame away from the liner, thus ensuring the liner is not overly heated. Further, the baffle is used to create a uniform flame temperature within the combustion chamber. The shaping can further ensure that the combustion section or otherwise hot sections of the turbine engine do not fail or otherwise become ineffective by being overly heated, thus increasing the lifespan of the turbine engine.

Benefits associated with using hydrogen-containing fuel over conventional fuels include an eco-friendlier engine as the hydrogen-containing fuel, when combusted, generates less carbon pollutants than a combustor using conventional fuels. For example, a combustor including <NUM>% hydrogen-containing fuel (e.g., the fuel is <NUM>% H<NUM>) would have zero carbon pollutants. The combustor, as described herein, can be used in instances where <NUM>% hydrogen-containing fuel is used.

Further benefits associated with using hydrogen-containing fuel over conventional fuels include a gas turbine engine that can utilize less fuel due to higher heating value of fuel to achieve same turbine inlet temperatures. For example, a conventional gas turbine engine using conventional fuels will require more fuel to produce the same amount of work or engine output as the present gas turbine engine using hydrogen-containing fuels. This, in turn, means that either less amount of fuel can be used to generate the same amount of engine output as a conventional gas turbine engine, or the same amount of fuel can be used to generate an increased engine output when compared to the conventional gas turbine engine.

To the extent not already described, the different features and structures of the various embodiments can be used in combination, or in substitution with each other as desired. That one feature is not illustrated in all of the embodiments is not meant to be construed that it cannot be so illustrated, but is done for brevity of description. Thus, the various features of the different embodiments can be mixed and matched as desired to form new embodiments, whether or not the new embodiments are expressly described. All combinations or permutations of features described herein are covered by this disclosure.

Claim 1:
A combustor (<NUM>, <NUM>, <NUM>, <NUM>) for a gas turbine engine (<NUM>), the combustor (<NUM>, <NUM>, <NUM>, <NUM>) comprising:
a casing (<NUM>, <NUM>, <NUM>, <NUM>);
an inner liner (882b, 982b) and an outer liner (<NUM>, <NUM>, 882a, 982a);
a compressed air passageway (<NUM>, <NUM>, <NUM>, <NUM>) formed between the casing (<NUM>, <NUM>, <NUM>, <NUM>), the inner liner (882b, 982b) and the outer liner (<NUM>, <NUM>, 882a, 982a), with at least a portion of the compressed air passageway (<NUM>, <NUM>, <NUM>, <NUM>) being split, via a wall (<NUM>, <NUM>, <NUM>, <NUM>), between a first channel (<NUM>, <NUM>, <NUM>, <NUM>) and a second channel (<NUM>, <NUM>, <NUM>, <NUM>);
a combustion chamber (<NUM>, <NUM>, <NUM>, <NUM>) at least partially defined by the inner liner (882b, 982b) and the outer liner (<NUM>, <NUM>, 882a, 982a), the combustion chamber (<NUM>, <NUM>, <NUM>, <NUM>) having a mean centerline (<NUM>, <NUM>, <NUM>, <NUM>) extending through the combustion chamber (<NUM>, <NUM>, <NUM>, <NUM>), the mean centerline (<NUM>, <NUM>, <NUM>, <NUM>) being equidistant between the inner liner (882b, 982b) and the outer liner (<NUM>, <NUM>, 882a, 982a);
at least one dilution passage (<NUM>, <NUM>, <NUM>, <NUM>) extending through at least one of the the inner liner (882b, 982b) and the outer liner (<NUM>, <NUM>, 882a, 982a), the at least one dilution passage (<NUM>, <NUM>, <NUM>, <NUM>) extending between an inlet (<NUM>, <NUM>, <NUM>, <NUM>) fluidly coupled to the first channel (<NUM>, <NUM>, <NUM>, <NUM>) and a dilution hole (<NUM>, <NUM>, <NUM>, <NUM>) fluidly coupled to the combustion chamber (<NUM>, <NUM>, <NUM>, <NUM>);
a first arm (<NUM>, <NUM>, <NUM>, <NUM>);
a second arm (<NUM>, <NUM>, <NUM>, <NUM>) statically coupled to a portion of the casing <NUM>, <NUM>, <NUM>, <NUM>); and
a baffle (<NUM>, <NUM>, <NUM>, <NUM>) extending between the first arm (<NUM>, <NUM>, <NUM>, <NUM>) and the second arm (<NUM>, <NUM>, <NUM>, <NUM>), the baffle (<NUM>, <NUM>, <NUM>, <NUM>) provided within the compressed air passageway (<NUM>, <NUM>, <NUM>, <NUM>) and having a range of movement between a first position and a second position relative to the inlet (<NUM>, <NUM>, <NUM>, <NUM>) of the at least one dilution passage (<NUM>, <NUM>, <NUM>, <NUM>) to control a degree of occlusion of compressed airflow (C) to the first channel (<NUM>, <NUM>, <NUM>, <NUM>).