TECHNICAL FIELD
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The invention relates to combustor liners, and more specifically to combustor v-band rings that provide cooling as well as promote beneficial flow characteristics within the combustor.
BACKGROUND
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Gas turbine engine combustors utilize cooling holes to thermally protect combustor walls and/or combustor liners from the heat of combustion. In some instances, v-band louvers and/or v-band rings are used to direct cooling air along the combustor liner in the upstream direction and the downstream direction relative to a flow through the combustor. As v-band louvers and/or rings protrude into the combustor chamber, high temperature and high pressure from combustion can wear effusion cooling features such as the v-band. While prior v-band designs are considered suitable for their intended purpose, improved cooling and/or improved louver construction is highly desirable.
SUMMARY
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An insert according to an aspect of the present invention includes a body, a passage, and an outlet. The body extends from a proximal end to a distal end. The passage extends through the proximal end of the body towards the distal end. The outlet extends through the body at the distal end to fluidly connect to the passage. The passage and the outlet form a fluid path through the insert.
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A combustor according to another aspect of the present invention includes a wall circumscribing an axis and at least partially bounding a combustion chamber inward from the wall and at least partially bounding a plenum outward from the wall. The wall includes an aperture that receives the insert.
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A combustor according to another aspect of the present invention includes an inner wall circumscribing an axis and an outer wall spaced outward relative to the inner wall to at least partially bound a combustion chamber. The outer wall includes a v-band. The v-band includes, in series, a first frustoconical segment that extends inward towards the axis, a convex segment that extends from the first frustoconical segment, and a second frustoconical segment that extends from the convex segment outward from the axis. An aperture extends through the convex segment that receives the insert.
BRIEF DESCRIPTION OF THE DRAWINGS
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- FIG. 1 is an axial cross-section through an example gas turbine engine.
- FIG. 2 is an axial cross-section through a combustor of the example gas turbine engine that includes an array of inserts extending through a v-band ring.
- FIG. 3 is an enlarged axial cross-sectional view of the combustor from FIG. 2 depicting the insert in greater detail.
- FIG. 4 is a cross-sectional view taken through v-band depicting further details of the insert.
- FIG. 5 is an isometric view of the insert removed from the combustor wall.
DETAILED DESCRIPTION
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As disclosed herein, one or more inserts are configured to redirect cooling fluid along a combustor wall surface as film cooling. Inserts are received within apertures extending through apertures of one or more combustor walls such that a distal end protrudes into the combustion chamber. A passage extending within the insert directs cooling fluid from a plenum exterior to the combustion chamber along an interior surface of a combustor wall via an outlet. Inserts 58 facilitate greater flexibility of combustor effusion cooling as inserts can include a variety of outlet orientations. Further, modification of existing combustor effusion cooling configurations and/or maintenance of existing configurations can be achieved by replacing inserts during a scheduled or unscheduled maintenance interval of gas turbine engine.
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FIG. 1 is an axial cross-section through an example gas turbine engine 10 that can be equipped with a combustor with one or more inserts for directing cooling fluid along the combustor walls. While gas turbine engine 10 is depicted as a turbofan engine, inserts can be incorporated into combustors of other types of gas turbine engines. In some examples, gas turbine engine 10 can be a turboshaft engine or a turboprop engine suitable for propulsion of an aircraft and/or providing power to an auxiliary system of the aircraft (e.g., an auxiliary power unit). In other examples, gas turbine engine 10 can be a ground-based industrial gas turbine engine or an aeroderivative gas turbine engine. Further, gas turbine engine 10 can include fewer or more compressor stages and/or turbine stages than the number of stages depicted by FIG.1 and said stages can be configured as axial compressors and/or turbines, or centrifugal compressors and/or turbines arranged to form fewer or more shaft spools than the configuration depicted in FIG. 1.
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As depicted in FIG. 1, gas turbine engine 10 includes inlet 12, fan 14, fan case 16, bypass duct 18, low-pressure axial compressor 20, high-pressure centrifugal compressor 22, diffuser 24, plenum 26, combustor 28, fuel tubes 30, nozzle guide vane 32, turbines 34, and exhaust nozzle 36. Air intake into gas turbine engine 10 through inlet 12 passes over fan 14 in fan case 16 and is then split into an outer annular flow through the bypass duct 18 and an inner flow through the low-pressure axial compressor 20 and high-pressure centrifugal compressor 22. Compressed air exits high-pressure centrifugal compressor 22 through diffuser 24 and is contained within plenum 26 that surrounds combustor 28. Fuel supplied to combustor 28 through fuel tubes 30 mixes with air supplied from plenum 26 when sprayed through nozzles into combustor 28 as a fuel air mixture and is ignited. A portion of the compressed air within plenum 26 is admitted into combustor 28 through orifices in the side walls to create a cooling air film along the combustor walls or is used for cooling, which eventually mixes with the hot gases from combustor 28 and passes over nozzle guide vane 32 and turbines 34 before exiting nozzle 36 as exhaust. It will be understood that the foregoing description is intended to be exemplary of only one of many possible configurations of engine suitable for incorporation of the present invention.
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FIG. 2 is an axial cross-section of combustor 28 with inner wall 38, outer wall 40, head wall 42 (collectively liner walls), and v-band ring 44. Inner wall 38 is spaced radially inward from outer wall 40 relative to centerline axis C to form annular combustion chamber 46. Head wall 42 extends from inner wall 38 to outer wall 40 to enclose an upstream end of combustor 28. Fuel tube 30 communicates with combustion chamber 46 via a port extending through head wall 42, however, the fuel nozzle arrangement is not shown, for simplicity. An ignitor extends through a port of outer wall 40 and is positioned in relation to one or more fuel tubes 30 to initiate combustion within combustion chamber 46.
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V-band ring 44 forms a section of inner wall 38 or outer wall 40 and is spaced downstream from ignitor (not shown) and head wall 42. Examples of combustor 28 can include v-band ring 44 disposed between a primary combustor zone into which fuel is injected and a downstream zone into which additional air is introduced for mixing with fuel for combustion as shown in FIG. 2. V-band ring 44 includes one or more cooling passages 48 that fluidly connect plenum 26 to combustion chamber 46 for distributing air along an inner surface of v-band ring 44 and outer wall 40 in an upstream direction (i.e., towards head wall 42) and/or in a downstream direction (i.e., towards turbine 34). While the example depicted by FIG. 2 and FIG. 3 show v-band ring 44 as part of outer wall 40, v-band ring 44 can be incorporated into inner wall 38 in other examples. Features of v-band ring 44 described below in reference to outer wall 40 can be applied to inner wall 38 in these examples.
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FIG. 3 is an enlarged cross-section of the v-band ring 44 of outer wall 40. V-band ring 44 is a portion of inner wall 38 or outer wall 40 that forms a V-shaped cross-section in a plane that includes axis C. V-band ring 44 includes, in series, frustoconical segment 50, convex segment 52, and frustoconical segment 54. Frustoconical segment 50 extends inward toward axis C to join convex segment 52, which forms a radially innermost portion of v-band ring 44. Frustoconical segment 54 extends from convex segment 52 outward relative to axis C. Convex segment 52 can formed a rounded convex profile of v-band, which reduces flow distributions within combustor 28.
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Outer wall 40, inner wall 38, and/or v-band ring 44 can include one or more apertures 56A-56N configured to receive one or more inserts 58A-58N, in which "N" denotes an arbitrary number of apertures 56 and an equal number of inserts 58. As depicted in FIG. 3, convex segment 52 includes at least one aperture 56A that receives insert 58A while other examples of convex segment 52 includes apertures 56A-56N, each receiving one of inserts 58A-58N. Outer wall 40, inner wall 38, and/or v-band ring 44 can include one or more cooling holes 60 for cooling surfaces of combustor 28. Further, outer wall 40 and/or inner wall 38 can include one or more dilution holes 62 to achieve a desired fuel-to-air mixture within combustion chamber 46.
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FIG. 4 is a cross-sectional view through v-band ring 44 and inserts 58A-58N received within respective apertures 56A-56N. FIG. 5 is an isometric view of insert 58 removed from v-band ring 44. FIG. 4 and FIG. 5 are discussed together below.
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Each insert 58 includes body 64, passage 48, and outlet 66. Body 64 extends along extension direction E from proximal end 64A to distal end 64B, which protrudes into combustion chamber 46 when assembled with a wall of combustor 28. An exterior surface of body 64 conforms to a shape of aperture 56. For example, aperture 56 can be a cylindrical bore and body 64 can be tubular such that the exterior surface of body 64 defines a gap with aperture 56 as depicted by FIG. 4. Passage 48 extends at least partially through body 64, and outlet 66 extends through body 64 to intersect passage 48. Together, passage 48 and outlet 66 fluidly connect a region exterior to outer wall 40 (e.g., plenum 26) to a region interior to outer wall 40 (e.g., combustion chamber 46).
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Outlet 66 can extend at an angle to passage 48 to redirect cooling fluid from passage 48 along a wall or other feature of combustor 28. Outlet 66 can be perpendicular to passage 48 in some examples, while outlet 66 can form an included obtuse angle with passage 48 in other examples. In another example, outlet 66 can extend parallel to passage 48.
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With insert 58 assembled within aperture 56, the orientation of outlet 66 redirects cooling fluid from passage 48 along an interior surface of a wall of combustion chamber 46 (e.g., an interior surface of outer wall 40). Outlet 66 can be directed in a radially inward direction, a tangential direction, an upstream direction, and a downstream direction, or a combination of directions. For example, outlet 66 can direct cooling fluid along a tangential direction as shown in FIG. 4. In other examples, outlet 66 can include a radially inward component combined with one or more of a tangential component and an axial component (e.g., either an upstream component or a downstream component) relative to axis C.
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In some examples, proximal end 64A of insert 58 can include flange 68. Flange 68 extends outward from body 64 of insert 58 to form a stop. When assembled with combustor 28, flange abuts an exterior surface of outer wall 40, or other combustor wall, to prevent insert 58 from translating inward through aperture into combustion chamber 46. Flange 68 can include an elongated portion such as tab 70. Tab 70 engages outer wall 40 to restrain insert 58 rotationally about extension direction E with respect to outer wall 40. For instance, flange 68 and/or tab 70 can engage a recess, a protrusion, or other feature of outer wall 40 to restrain rotation of insert 58 relative to outer wall 40. In other examples, tab 70 can be affixed to wall via pin or other mechanical connection. Examples of insert 58 without tab 70 can be positioned relative to outer wall 40, or other combustor wall, by external tooling that restrains insert 58 relative to outer wall 40.
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Distal end 64B of insert 58 can be shaped to minimize flow disruptions within combustor 28. For instance, distal end 64B of insert 58 can be hemispherical as shown in FIG. 4 and FIG. 5. In other examples, distal end 64B can be ellipsoidal or otherwise contoured. In still other examples, distal end 64B can be flat with or without a radius forming a transition with exterior surface of body 64.
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Inserts 58 are joined with outer wall 40, or another wall of combustor 28, by a mechanical connection between body 64 and aperture 56 and/or between flange 68 and/or exterior surface of outer wall 40. For example, the gap formed between body 64 of insert 58 and aperture 56 can be sized to accept a braze preform therebetween that, when heated to the designated temperature, brazes inserts 58 to outer wall 40 at an exterior surface of body 64. In another example, flange 68 can be fitted with another braze preform to form a braze joint with outer wall 40 upon heating to the designated temperature. In still other examples, a preform at flange 68 can be used to flow braze filler into the gap. In lieu of a braze joint, insert 58 can be affixed to outer wall 40 via a weld, a pin, or another mechanical connection. In further examples, a combination of any of the foregoing mechanical connections can be used.
Discussion of Possible Embodiments
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The following are non-exclusive descriptions of possible embodiments of the present invention.
An insert for effusion cooling of a wall
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An insert according to an example embodiment of this disclosure, among other possible things, includes a body, a passage, and an outlet. The body extends from a proximal end to a distal end. The distal end is configured to protrude through a wall. The passage extends at least partially through the body towards the distal end. the outlet extends through the body at the distal end to fluidly connect with the passage. The passage and the outlet form a fluid path through the insert.
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The insert of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components.
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A further embodiment of the foregoing insert, wherein the body of the insert can be tubular.
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A further embodiment of any of the foregoing inserts, wherein the outer surface of the body can be configured to conform to an aperture to define a gap.
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A further embodiment of any of the foregoing inserts, wherein a distal end of the body can be hemispherical.
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A further embodiment of any of the foregoing inserts can further include a flange extending from the proximal end of the insert.
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A further embodiment of any of the foregoing inserts, wherein the flange includes an elongated portion that forms a tab.
A combustor for a gas turbine engine
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A combustor according to an example embodiment of this disclosure, among other possible things, includes a wall, an aperture, and an insert. The wall circumscribes an axis and at least partially bounding a combustion chamber inward from the wall and at least partially bounding a plenum outward from the wall relative to the axis. The aperture extends through the wall. The insert is received within the aperture and protrudes into the combustion chamber. The insert includes a body, a passage, and an outlet. The body extends from a proximal end to a distal end, which protrudes into the combustion chamber. The passage extends from the plenum at least partially through the body towards the distal end. The outlet extends through the body at the distal end to fluidly connect the passage to the combustion chamber.
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The combustor of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components.
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A further embodiment of the foregoing combustor, wherein the aperture can be a cylindrical bore.
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A further embodiment of any of the foregoing combustors, wherein the body of the insert can be tubular.
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A further embodiment of any of the foregoing combustors, wherein an outer surface of the body can conform to the cylindrical bore to define a gap.
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A further embodiment of any of the foregoing combustors, wherein the distal end of the body can be hemispherical.
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A further embodiment of any of the foregoing combustors, wherein the insert can further include a flange extending from the proximal end of the insert that abuts an outer surface of the wall.
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A further embodiment of any of the foregoing combustors, wherein the flange can include a tab that engages the wall to restrain the insert in rotation about an extension axis of the insert.
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A further embodiment of any of the foregoing combustors, wherein a braze joint between an exterior surface of the body and the wall can attach the insert to the wall.
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A further embodiment of any of the foregoing combustors, wherein the outlet can have a tangential orientation about the axis.
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A further embodiment of any of the foregoing combustors, wherein the aperture can be one of a plurality of apertures, each extending through the wall.
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A further embodiment of any of the foregoing combustors, wherein the insert is one of a plurality of inserts, each insert received in one of the plurality of apertures.
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A further embodiment of any of the foregoing combustors, wherein outlets of the plurality of inserts can have a tangential orientation about the axis.
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A further embodiment of any of the foregoing combustors, wherein at least one outlet of the plurality of inserts can have an orientation with a tangential component and one of an upstream component and a downstream component relative to the axis.
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A further embodiment of any of the foregoing combustors, wherein each aperture of the plurality of apertures can have a cylindrical bore.
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A further embodiment of any of the foregoing combustors, wherein each body of the plurality of inserts can be tubular.
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A further embodiment of any of the foregoing combustors, wherein each distal end of the plurality of inserts can be hemispherical.
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A further embodiment of any of the foregoing combustors, wherein each insert of the plurality of inserts can further include a flange abutting an outer surface of the wall to restrain each insert in a direction towards the combustion chamber.
A combustor for a gas turbine engine
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A combustor according to another example of this disclosure, among other possible things, includes an inner wall, an outer wall, an aperture, and an insert. The inner wall circumscribes an axis. The outer wall is spaced outward relative to the inner wall to at least partially bound a combustion chamber. The inner wall or the outer wall includes a v-band that includes, in series, a first frustoconical segment extending inward towards the axis, a convex segment extending from the first frustoconical segment, and a second frustoconical segment extending from the convex segment outward from the axis that form a V-shaped cross-section in a plane including the axis. The aperture extends through the convex segment. The insert is received within the aperture and protrudes into the combustion chamber. The insert includes a body, a passage, and an outlet. The body extends from a proximal end to a distal end, which protrudes into the combustion chamber. The passage extends at least partially through the body towards the distal end. The outlet extends through the body at the distal end to fluidly connect the passage to the combustion chamber.
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The combustor of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components.
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A further embodiment of the foregoing combustor, wherein the aperture can be a cylindrical bore.
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A further embodiment of any of the foregoing combustors, wherein the body of the insert can be tubular.
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A further embodiment of any of the foregoing combustors, wherein an outer surface of the body can conform to the cylindrical bore to define a gap.
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A further embodiment of any of the foregoing combustors, wherein the distal end of the body can be hemispherical.
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A further embodiment of any of the foregoing combustors, wherein the insert can further include a flange extending from the proximal end of the insert that abuts an exterior surface of the outer wall.
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A further embodiment of any of the foregoing combustors, wherein the flange can include a tab that engages the outer wall to restrain the insert in rotation about an extension axis of the insert.
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A further embodiment of any of the foregoing combustors, wherein a braze joint between an exterior surface of the body and the aperture can attach the insert to the outer wall.
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A further embodiment of any of the foregoing combustors, wherein the outlet can have a tangential orientation about the axis.
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A further embodiment of any of the foregoing combustors can further include a head wall extending from the inner wall to the outer wall to enclose an upstream end of the combustion chamber.
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A further embodiment of any of the foregoing combustors, wherein the outlet of the insert can have an orientation with a tangential component and an upstream component towards the head wall.
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A further embodiment of any of the foregoing combustors, wherein the outlet of the insert can have an orientation with a tangential component and a downstream component facing away from the head wall.
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A further embodiment of any of the foregoing combustors, wherein the aperture can be one of a plurality of apertures, each extending through the outer wall.
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A further embodiment of any of the foregoing combustors, wherein the insert is one of a plurality of inserts, each insert received in one of the plurality of apertures.
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A further embodiment of any of the foregoing combustors, wherein outlets of the plurality of inserts can have a tangential orientation about the axis.
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A further embodiment of any of the foregoing combustors, wherein at least one outlet of the plurality of inserts can have an orientation with a tangential component and one of an upstream component and a downstream component relative to the axis.
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A further embodiment of any of the foregoing combustors, wherein each aperture of the plurality of apertures can have a cylindrical bore.
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A further embodiment of any of the foregoing combustors, wherein each body of the plurality of inserts can be tubular.
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A further embodiment of any of the foregoing combustors, wherein each distal end of the plurality of inserts can be hemispherical.
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A further embodiment of any of the foregoing combustors, wherein each insert of the plurality of inserts can further include a flange abutting an outer surface of the wall to restrain each insert in a direction towards the combustion chamber.
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While the invention has been described with reference to an exemplary embodiment(s), it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment(s) disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.