EP3428535A1

EP3428535A1 - A combustor triple liner assembly for gas turbine engines

Info

Publication number: EP3428535A1
Application number: EP17181053.4A
Authority: EP
Inventors: Kexin Liu
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 2017-07-12
Filing date: 2017-07-12
Publication date: 2019-01-16
Also published as: US20190017705A1

Abstract

A combustor triple liner assembly includes coaxially aligned and radially spaced cylindrical inner, middle and outer liners forming an inner annular flow-path between the inner and the middle liners, and an outer annular flow-path between the middle and the outer liners. A plurality of inner dividers segments the inner annular flow-path into inner compartments. A plurality of outer dividers segments the outer annular flow-path into outer compartments and the middle liner into middle liner sections corresponding to each outer compartment. Each middle liner section includes a plurality of impingement holes fluidly connecting the outer compartment to one corresponding inner compartment which in turn is fluidly connected to one corresponding downstream outer compartment through an opening in the middle liner, such that cooling air flows from the outer compartment through the impingement holes into the corresponding inner compartment and therefrom through the opening into the corresponding downstream outer compartment.

Description

The present invention relates to gas turbines, and more particularly to combustor assemblies gas turbine engines.
To effectively use cooling air for cooling of gas turbine components is a constant challenge and an important area of interest in gas turbine engine designs. For example, for combustor liner cooling, conventional design uses many impingement holes spread in a large area of a cooling air channel wall or plate, such as a conventional burner plenum surface, overhanging or in close vicinity of the target surface. The cooling air emerges from the impingement holes in form of impingement jets and flows towards the target surface, for example a combustor liner surface, which is to be cooled in order to impact the target surface normally. It is important to have an adequate velocity in the impingement jets in order for the cooling air to reach the target surface and thus to cool the target surface. Therefore to achieve adequately high velocity in the impingement jets, size of the impingement holes is required to be small but concentration of impingement holes in a given area is high to ensure adequate volume of the cooling air is available to the target surface. However, since most of the target surfaces, especially combustion liner surface, are longitudinally extended, the impingement jets delivering the cooling air to downstream sections of the combustion liner surface are subjected to strong cross flow resulting from the cooling air that has entered through the impingement jets delivering the cooling air to upstream sections of the target surface and then flowing across the longitudinally extended target surface from the upstream section to the downstream section of the longitudinally extended target surface.
The cross-flow affects the impingement jets delivering cooling air to the downstream sections of the combustion liner surface. The substantially normal flow of the cooling air in the impingement jets towards the target surface is disturbed by the cross flowing cooling air which flows substantially parallel to the target surface and as a result the impingement jets delivering cooling air to the downstream sections of the target surface may not impinge on the target surface especially in the downstream sections of the longitudinally extended target surface. The disturbance to the impingement jets as a result of the cross flow is increased as the cross flow gains more and more volume from the impingement jets received by the cross flow as the cross flow travels from the upstream section of the target surface to the downstream section of the target surface. Therefore, an improvement in cooling air flow in a combustor is desired.
Thus an object of the present technique is to provide a combustor assembly for a gas turbine engine that minimizes the disturbances due to the cross flow of the cooling air over longitudinally extended target surfaces such as a combustor liner surface that are to be cooled by impingement jets. Another object of the present technique is to reduce the amount of cooling air usage and increase the engine efficiency by re-circulating the cooling air from one flow path to another, and thus more air is available for combustion.
The above objects are achieved by a combustor triple liner assembly according to claim 1, a combustor assembly according to claim 12, and a gas turbine engine according to claim 13 of the present technique. Advantageous embodiments of the present technique are provided in dependent claims. Features of independent claims may be combined with features of claims dependent on that independent claim, and features of dependent claims can be combined together.
In a first aspect of the present technique, a combustor triple liner assembly for a gas turbine engine is presented. The combustor triple liner assembly includes an inner liner, a middle liner, an outer liner, a plurality of inner dividers and a plurality of outer dividers. The inner liner is a cylinder and has a longitudinal axis. A space defined or contained within the cylindrical inner liner defines a combustion chamber. The middle liner is a cylinder that houses the inner liner. The outer liner is a cylinder that houses the middle liner. Thus, the inner liner is housed in the middle liner and the middle liner is in turn housed in the outer liner. The inner liner, the middle liner and the outer liner are coaxially aligned about the longitudinal axis and are radially separated with respect to the longitudinal axis to create an inner annular flow-path between the inner liner and the middle liner, and to create an outer annular flow-path between the middle liner and the outer liner.
The inner dividers are serially arranged longitudinally within the inner annular flow-path. Each of the inner dividers are annular disc shaped and the radial direction of the disc shaped inner dividers is aligned perpendicular to the longitudinal axis i.e. each inner divider extends radially about the longitudinal axis between the inner liner and the middle liner thereby dividing the inner annular flow-path into a plurality of inner compartments.
The outer dividers are serially arranged longitudinally within the outer annular flow-path. Each of the outer dividers are annular disc shaped and the radial direction of the disc shaped outer dividers is aligned perpendicular to the longitudinal axis i.e. each outer divider extends radially about the longitudinal axis between the middle liner and the outer liner thereby dividing the outer annular flow-path into a plurality of outer compartments. The outer dividers also divide or segment the middle liner into a plurality of middle liner sections corresponding to each outer compartment i.e. each of outer compartments includes a middle liner section.
The middle liner section of each outer compartment includes a plurality of impingement holes. The impingement holes of each outer compartment fluidly connect that outer compartment to one corresponding inner compartment and the corresponding inner compartment is fluidly connected to one corresponding downstream outer compartment through at least one opening in the middle liner of the downstream outer compartment, such that cooling air entering the outer annular flow-path flows from the outer compartment through the impingement holes of the outer compartment into the corresponding inner compartment and therefrom through the opening into the corresponding downstream outer compartment.
As an effect of the flow of the cooling air serially flowing through the outer compartment into the corresponding inner compartment through the impingement holes and then into the corresponding downstream outer compartment and then into the inner compartment corresponding to the corresponding downstream outer compartment and so on and so forth, buildup of strong cross flow with respect to impingement jets is minimized and thus the impingement jets emanating from the impingement holes of different middle liner sections are able to reach the inner liner and provide effective cooling to the inner liner. Furthermore, sizes of the impingement holes can be controlled individually for different middle liner sections and thus parameters of the impingement jets produced by different middle liner sections, such as velocity of the impingement jets, can be controlled and thereby different degrees of cooling can be achieved locally for different sections of the inner liner. Furthermore, by such recirculation of the cooling air form one compartment to another one, less cooling air is required and engine efficiency is increased. Furthermore, since the combustor triple liner assembly requires only three parts or components i.e. the inner liner, the middle liner, and the outer liner in addition to the inner and the outer dividers, the construction and assembly of the combustor triple liner assembly is simple and does not require complicated assembling of multiple individual parts.
In an embodiment of the combustor triple liner assembly, the inner liner includes a plurality of film cooling holes. The film cooling holes allow a part of the cooling air from at least one of the inner compartments, where the film cooling holes are located, to enter the combustion chamber and to provide film cooling of an inner surface of the inner liner. The part of the cooling air flowing into the combustion chamber from the inner compartment through the film cooling holes also provides combustion acoustic damping of the inner liner.
In another embodiment of the combustor triple liner assembly, the inner liner includes at least one dilution hole. The dilution holes allows a part of the cooling air from at least one of the inner compartments, where the dilution hole is located, to enter the combustion chamber and thereby dilute the combustion gases in the combustion chamber. The part of the cooling air flowing into the combustion chamber from the inner compartment through the dilution hole mixes with the combustion gas or the working gas and reduces temperature of the combustion gas.
In another embodiment of the combustor triple liner assembly, the impingement holes are located in the middle liner section of each outer compartment as an array. The array extends circumferentially and axially in the middle liner section and thus impingement jets emanate from entire area or expanse of the middle liner sections.
In another embodiment of the combustor triple liner assembly, at least one of the outer dividers includes one or more by-pass holes. The by-pass holes allow a part of the cooling air to flow from the outer compartment upstream of the outer divider to the outer compartment downstream of the outer divider, without flowing through any inner compartment. The part of the cooling air flowing from the upstream outer compartment into the adjacent downstream outer compartment is cooler than the part of the cooling air flowing into the downstream outer compartment from the inner compartment. This cooler cooling air mixes with the cooling air flowing into the downstream outer compartment from the inner compartment and reduces the temperature of the cooling air in the downstream outer compartment which then flows into the corresponding inner compartment to cool the inner liner.
In another embodiment of the combustor triple liner assembly, the outer dividers and the inner dividers are integrally formed with the middle liner. Thus the combustor triple liner assembly requires only three parts or components i.e. the inner liner, the middle liner with the integrally formed inner and outer dividers, and the outer liner, and therefore the construction and assembly of the combustor triple liner assembly is simple and does not require complicated assembling of multiple individual parts.
In another embodiment of the combustor triple liner assembly, the outer dividers are integrally formed with the middle liner, whereas the inner dividers are integrally formed with the inner liner. Thus, the combustor triple liner assembly requires only three parts or components i.e. the inner liner with the integrally formed inner dividers, the middle liner with the integrally formed outer dividers, and the outer liner. Therefore the construction and assembly of the combustor triple liner assembly is simple and does not require complicated assembling of multiple individual parts. In another embodiment of the combustor triple liner assembly, the outer dividers are integrally formed with the outer liner, whereas the inner dividers are integrally formed with the middle liner. Thus, the combustor triple liner assembly requires only three parts or components i.e. the inner liner, the middle liner with the integrally formed inner dividers, and the outer liner with the integrally formed outer dividers. Therefore the construction and assembly of the combustor triple liner assembly is simple and does not require complicated assembling of multiple individual parts.
In another embodiment of the combustor triple liner assembly, the outer dividers are integrally formed with the outer liner, whereas the inner dividers are integrally formed with the inner liner. Thus, the combustor triple liner assembly requires only three parts or components i.e. the inner liner with the integrally formed inner dividers, the middle liner, and the outer liner with the integrally formed outer dividers. Therefore the construction and assembly of the combustor triple liner assembly is simple and does not require complicated assembling of multiple individual parts.
In a second aspect of the present technique, a combustor assembly is presented. The combustor assembly includes a burner and a combustor triple liner assembly. The combustor triple liner assembly is according to the first aspect of the present technique.
In a third aspect of the present technique, a gas turbine engine is presented. The gas turbine engine includes a combustor triple liner assembly. The combustor triple liner assembly is according to the first aspect of the present technique.
The above mentioned attributes and other features and advantages of the present technique and the manner of attaining them will become more apparent and the present technique itself will be better understood by reference to the following description of embodiments of the present technique taken in conjunction with the accompanying drawings, wherein:

FIG 1: shows part of a gas turbine engine in a sectional view and in which an exemplary embodiment of a combustor triple liner assembly of the present technique is incorporated;
FIG 2: schematically illustrates an embodiment of the combustor triple liner assembly from FIG 1;
FIG 3: schematically illustrates a perspective view of another embodiment of a section of the combustor triple liner assembly of FIG 2 depicting further structural details of the combustor triple liner assembly;
FIG 4: schematically illustrates a perspective view of an exemplary embodiment of a section of an inner liner of the combustor triple liner assembly;
FIG 5: schematically illustrates a perspective view of another exemplary embodiment of a section of the inner liner of the combustor triple liner assembly;
FIG 6: schematically illustrates a perspective view of an exemplary embodiment of a section of a middle liner of the combustor triple liner assembly;
FIG 7: schematically illustrates an exemplary scheme of cooling air flow within an exemplary embodiment of the combustor triple liner assembly;
FIG 8: schematically illustrates an exploded view of an exemplary embodiment of the combustor triple liner assembly;
FIG 9: schematically illustrates an exploded view of another exemplary embodiment of the combustor triple liner assembly;
FIG 10: schematically illustrates an exploded view of yet another exemplary embodiment of the combustor triple liner assembly; and
FIG 11: schematically illustrates an exploded view of a further exemplary embodiment of the combustor triple liner assembly; in accordance with aspects of the present technique.

Hereinafter, above-mentioned and other features of the present technique are described in details. Various embodiments are described with reference to the drawing, wherein like reference numerals are used to refer to like elements throughout. In the following description, for purpose of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more embodiments. It may be noted that the illustrated embodiments are intended to explain, and not to limit the invention. It may be evident that such embodiments may be practiced without these specific details.
FIG. 1 shows an example of a gas turbine engine 10 in a sectional view. The gas turbine engine 10 comprises, in flow series, an inlet 12, a compressor or compressor section 14, a combustor section 16 and a turbine section 18 which are generally arranged in flow series and generally about and in the direction of a rotational axis 20. The gas turbine engine 10 further comprises a shaft 22 which is rotatable about the rotational axis 20 and which extends longitudinally through the gas turbine engine 10. The shaft 22 drivingly connects the turbine section 18 to the compressor section 14.
In operation of the gas turbine engine 10, air 24, which is taken in through the air inlet 12 is compressed by the compressor section 14 and delivered to the combustion section or burner section 16. The burner section 16 comprises a burner plenum 26, one or more combustion chambers 28 extending along a longitudinal axis 35 and at least one burner 30 fixed to each combustion chamber 28. The combustion chambers 28 and the burners 30 are located inside the burner plenum 26. The compressed air passing through the compressor 14 enters a diffuser 32 and is discharged from the diffuser 32 into the burner plenum 26 from where a portion of the air enters the burner 30 and is mixed with a gaseous or liquid fuel. The air/fuel mixture is then burned and the combustion gas 34 or working gas from the combustion is channelled through the combustion chamber 28 to the turbine section 18 via a transition duct 17. The combustion section 16 includes a combustor triple liner assembly 1 according to the present technique. The burner 30 and the combustor triple liner assembly 1 together form the combustor assembly 100 according to the present technique.
This exemplary gas turbine engine 10 has a cannular combustor section arrangement 16, which is constituted by an annular array of combustor cans 19 each having the burner 30 and the combustion chamber 28, the transition duct 17 has a generally circular inlet that interfaces with the combustor chamber 28 and an outlet in the form of an annular segment. An annular array of transition duct outlets form an annulus for channelling the combustion gases to the turbine 18.
The turbine section 18 comprises a number of blade carrying discs 36 attached to the shaft 22. In the present example, two discs 36 each carry an annular array of turbine blades 38. However, the number of blade carrying discs could be different, i.e. only one disc or more than two discs. In addition, guiding vanes 40, which are fixed to a stator 42 of the gas turbine engine 10, are disposed between the stages of annular arrays of turbine blades 38. Between the exit of the combustion chamber 28 and the leading turbine blades 38 inlet guiding vanes 44 are provided and turn the flow of working gas onto the turbine blades 38.
The combustion gas 34 from the combustion chamber 28 enters the turbine section 18 and drives the turbine blades 38 which in turn rotate the shaft 22. The guiding vanes 40, 44 serve to optimise the angle of the combustion or working gas 34 on the turbine blades 38.
The turbine section 18 drives the compressor section 14. The compressor section 14 comprises an axial series of vane stages 46 and rotor blade stages 48. The rotor blade stages 48 comprise a rotor disc supporting an annular array of blades. The compressor section 14 also comprises a casing 50 that surrounds the rotor stages and supports the vane stages 48. The guide vane stages include an annular array of radially extending vanes that are mounted to the casing 50. The vanes are provided to present gas flow at an optimal angle for the blades at a given engine operational point. Some of the guide vane stages have variable vanes, where the angle of the vanes, about their own longitudinal axis, can be adjusted for angle according to air flow characteristics that can occur at different engine operations conditions.
The casing 50 defines a radially outer surface 52 of the passage 56 of the compressor 14. A radially inner surface 54 of the passage 56 is at least partly defined by a rotor drum 53 of the rotor which is partly defined by the annular array of blades 48.
The present technique is described with reference to the above exemplary turbine engine having a single shaft or spool connecting a single, multi-stage compressor and a single, one or more stage turbine. However, it should be appreciated that the present technique is equally applicable to two or three shaft engines and which can be used for industrial, aero or marine applications. Furthermore, the cannular combustor section arrangement 16 is also used for exemplary purposes and it should be appreciated that the present technique is equally applicable to annular type and can type combustion chambers.
The terms upstream and downstream refer to the flow direction of the flow of cooling air unless otherwise stated. The terms forward and rearward refer to the general flow of cooling air through the burner section and particularly through the combustor triple liner assembly 1 of the present technique. The terms axial, radial and circumferential are made with reference to the longitudinal axis 35 of the combustion chamber 28, unless otherwise stated.
The basic idea of the invention is to segment the flow-path of the cooling air in such a way that development of cross flows is at least partially obviated. By the present technique the cooling air is effectively used i.e. for example less air is required for cooling and thus more air is available for combustion which in turn increases engine efficiency.
Referring to FIGs 2 and 3 in combination with FIGs 4,5 and 6, an exemplary embodiment of the combustor triple liner assembly 1 according to the present technique has been described hereinafter. The combustor triple liner assembly 1 is to be integrated or is integrated in the burner section or combustor section 16 of the gas turbine engine 10 of FIG 1.
The combustor triple liner assembly 1, hereinafter also referred to as the assembly 1, as depicted in FIGs 2 and 3, includes an inner liner 60, a middle liner 70, an outer liner 80, a plurality of inner dividers 92 and a plurality of outer dividers 93.
The inner liner 60 is a cylinder, or in other words is cylindrical in shape, and has a longitudinal axis that is same as the longitudinal axis 35. The combustion chamber 28 is defined in the space defined or contained within the cylindrical inner liner 60. The inner liner 60 has an inner surface 61 and an outer surface 62. The inner surface 61 forms the boundary of the combustion chamber 28 or in other words the inner surface 61 of the inner liner 60 faces the combustion chamber 28 or the longitudinal axis 35. The outer surface 62 is a surface opposite to the inner surface 61 i.e. the outer surface 62 faces away from the combustion chamber 28. The inner liner 60 is housed within the middle liner 70.
The middle liner 70 is a cylinder, or in other words is cylindrical in shape, and houses the inner liner 60. The middle liner 70 has an inner side 71 and an outer side 72. The inner side 71 is the surface of the middle liner 70 facing the inner liner 60 i.e. facing the longitudinal axis 35. The outer side 72 is the surface of the middle liner 70 opposite to the inner side 71 i.e. the outer side 72 faces away from the inner liner 60 and also the longitudinal axis 35. The inner liner 60 and the middle liner 70 are coaxially arranged about the longitudinal axis 35, hereinafter also referred to as the axis 35. The inner liner 60 and the middle liner 70 are radially spaced apart about the axis 35. A radial direction 5 about the axis 35 is schematically depicted in FIG 2. Thus the inner liner 60 and the middle liner 70 create a space between them, i.e. between the outer surface 62 of the inner liner 60 and the inner surface 71 of the middle liner 70. The space is an inner annular flow-path 2. As is depicted in FIGs 2 and 3, the inner liner 60 and the middle liner 70 extend longitudinally so as to cover or enwrap the combustion chamber 28. The middle liner 70 having the inner liner 60 housed therewithin is in turn housed within the outer liner 80.
The outer liner 80 is a cylinder, or in other words is cylindrical in shape, and houses the middle liner 70. The outer liner 80 has an inner side 81 and an outer side 82. The inner side 81 is the surface of the outer liner 80 facing the middle liner 70 i.e. facing the longitudinal axis 35. The outer side 82 is the surface of the outer liner 80 opposite to the inner side 81 i.e. the outer side 82 faces away from the middle liner 70 and also the longitudinal axis 35. The middle liner 70 and the outer liner 80 are coaxially arranged about the longitudinal axis 35. The middle liner 70 and the outer liner 80 are radially spaced apart about the axis 35 i.e. in the direction 5. Thus the middle liner 70 and the outer liner 80 create a space between them, i.e. between the outer surface 72 of the middle liner 70 and the inner surface 81 of the outer liner 80. The space is an outer annular flow-path 3. As is depicted in FIGs 2 and 3, the middle liner 70 and the outer liner 80 extend longitudinally so as to cover or enwrap the combustion chamber 28.
Thus, as depicted in FIGs 2 and 3 the inner liner 60 is housed in the middle liner 70 and the middle liner 70 is in turn housed in the outer liner 80. The inner liner 60, the middle liner 70 and the outer liner 80 are coaxially aligned about the longitudinal axis 35 and are radially separated with respect to the longitudinal axis 35 to create the inner annular flow-path 2 between the inner liner 60 and the middle liner 70, and to create the outer annular flow-path 3 between the middle liner 70 and the outer liner 80. Furthermore, the inner liner 60, the middle liner 70 and the outer liner 80 extend longitudinally so as to cover or enwrap the entire stretch of the combustion chamber 28.
As depicted in FIGs 2 and 3, the inner dividers 92 are serially arranged longitudinally, i.e. one inner divider 92 is separated from another inner divider 92 along the longitudinal axis 35. The inner dividers 92 are positioned within the inner annular flow-path 2. Each of the inner dividers 92 is a flat annular disc. The flat sides, i.e. the faces of the annular disc shaped inner dividers 92 are aligned perpendicular to the longitudinal axis 35, or in other words a radial direction of the annular disc shaped inner dividers 92 is aligned perpendicular to the longitudinal axis 35. Each inner divider 92 extends radially about the longitudinal axis 35 between the inner liner 60 and the middle liner 70 thereby dividing the inner annular flow-path 2 into a plurality of inner compartments 201,202,203. The two circumferential edges of each of the annular disc shaped inner dividers 92 are radially apart from each other by same distance as the radial separation between the outer surface 62 of the inner liner 60 and the inner surface 71 of the middle liner 70. In other words, an outer circumferential edge of the annular disc shaped inner divider 92 is in physical contact with the inner surface 71 of the middle liner 70 whereas an inner circumferential edge of the annular disc shaped inner divider 92 is in physical contact with the outer surface 62 of the inner liner 60, such cooling air 7 flowing into the inner annular flow-path 2 when encounters one of the inner dividers 92 cannot flow across the inner divider 92 unless a hole or an opening is provided through the inner divider 92 for flow of the cooling air 7. To explain further, each inner compartment 201,202,203 between any two of the inner dividers 92 is hermetically sealed by the inner dividers 92, the outer surface 62 of the inner liner 60, and the inner surface 71 of the middle liner 70 unless a hole or an opening is provided through the inner divider 92, or the inner liner 60, or the middle liner 70 to allow the cooling air 7 to flow out of the inner compartment 201,202,203.
As depicted in FIGs 2 and 3, the outer dividers 93 are serially arranged longitudinally, i.e. one outer divider 93 is separated from another outer divider 93 along the longitudinal axis 35. The outer dividers 93 are positioned within the outer annular flow-path 3. Each of the outer dividers 93 is a flat annular disc. The flat sides, i.e. the faces of the annular disc shaped outer dividers 93 are aligned perpendicular to the longitudinal axis 35, or in other words a radial direction of the annular disc shaped outer dividers 93 is aligned perpendicular to the longitudinal axis 35. Each outer divider 93 extends radially about the longitudinal axis 35 between the middle liner 70 and the outer liner 80 thereby dividing the outer annular flow-path 3 into a plurality of outer compartments 301,302,303. The two circumferential edges of each of the annular disc shaped outer dividers 93 are radially apart from each other by same distance as the radial separation between the outer surface 72 of the middle liner 70 and the inner surface 81 of the outer liner 80. In other words, an outer circumferential edge of the annular disc shaped outer divider 93 is in physical contact with the inner surface 81 of the outer liner 80 whereas an inner circumferential edge of the annular disc shaped outer divider 93 is in physical contact with the outer surface 72 of the middle liner 70, such cooling air 7 flowing into the outer annular flow-path 3 when encounters one of the outer dividers 93 cannot flow across the outer divider 93 unless a hole or an opening is provided through the outer divider 93 for flow of the cooling air 7. To explain further, each outer compartment 301,302,303 between any two of the outer dividers 93 is hermetically sealed by the outer dividers 93, the outer surface 72 of the middle liner 70, and the inner surface 81 of the outer liner 80 unless a hole or an opening is provided through the outer divider 93, or the middle liner 70, or the outer liner 80 to allow the cooling air 7 to flow out of the outer compartment 301,302,303.
The inner dividers 92 and the outer dividers 93 may be friction fitted or brazed or may be physically contacted in any other way with the inner liner 60 and middle liner 70, and with the middle liner 70 and the outer liner 80, respectively such that the corresponding physical contacts are air-tight.
As shown in FIG 3, the outer dividers 93 also divide or segment the middle liner 70 into a plurality of middle liner sections 701,702,703 corresponding to each outer compartment 301,302,303 i.e. each of outer compartment 301,302,303 includes one middle liner section 701,702,703, for example as depicted in the example of FIG 3 the outer compartment 301 includes the middle liner section 701, the outer compartment 302 includes the middle liner section 702, and the outer compartment 303 includes the middle liner section 703.
The middle liner section 701,702,703, of each outer compartment 301,302,303, includes a plurality of impingement holes 75. In an embodiment of the combustor triple liner assembly 1, the impingement holes 75 are positioned in form of an array that extends circumferentially and axially in the middle liner section 701,702,703. The impingement holes 75 of each outer compartment 301,302,303, fluidly connect that outer compartment 301,302,303, to one corresponding inner compartment 201,202,203, and the corresponding inner compartment 201,202,203, is fluidly connected to one corresponding downstream outer compartment 301,302,303, through at least one opening 77 in the middle liner 70 of the downstream outer compartment 301,302,303, such that cooling air entering the outer annular flow-path 3 flows from the outer compartment 301,302,303, through the impingement holes 75 of the outer compartment 301,302,303, into the corresponding inner compartment 201,202,203, and therefrom through the opening 77 into the corresponding downstream outer compartment 301,302,303. The scheme of flow of the cooling air 7 has been explained in further details with respect to FIG 7.
As shown in FIG 7, the cooling air 7 enters in the outer annular flow-path 3 in a direction depicted by arrow marked with reference numeral 91. The cooling air 7 is at this stage in one of the outer compartments 301,302,303, and in the example of FIG 7, the cooling air 7 at this stage is in the outer compartment 301. The middle liner section 701 of the outer compartment 301 has the impingement holes 75. The cooling air 7 flows through the impingement holes 75 of the middle liner section 701 of the outer compartment 301 into the corresponding inner compartment 201 in form of impingement jets 76 ejected from the impingement holes 75 to impact the outer surface 62 of the inner liner 60. Thereafter the cooling air 7 flows from the corresponding inner compartment 201 through the opening 77 into the corresponding downstream outer compartment 302. Thus, the cooling air 7 at this stage is in the outer compartment 302. The middle liner section 702 of the outer compartment 302 has the impingement holes 75. The cooling air 7 flows through the impingement holes 75 of the middle liner section 702 of the outer compartment 302 into the corresponding inner compartment 202 in form of impingement jets 76 ejected from the impingement holes 75 to impact the outer surface 62 of the inner liner 60. Thereafter the cooling air 7 flows from the corresponding inner compartment 202 through the opening 77 into the corresponding downstream outer compartment 303. The flow of the cooling air 7 continues according to this scheme in a general direction 9 of the flow of the cooling air 7. The cooling 7 flowing according to the aforementioned scheme reaches a last outer compartment, say the outer compartment 303. The middle liner section 703 of the outer compartment 303 has the impingement holes 75. The cooling air 7 flows through the impingement holes 75 of the middle liner section 703 of the outer compartment 303 into the corresponding inner compartment 203, i.e. the last inner compartment 203, in form of impingement jets 76 ejected from the impingement holes 75 to impact the outer surface 62 of the inner liner 60. Thereafter the cooling air 7 flows from the corresponding inner compartment 203 into one or more of the burners 30 to mix with fuel and burn inside the combustion chamber 28 as depicted by the arrow marked with reference numeral 99 in FIG 7, or the cooling air 7 may flow to some other structure (not shown).
Hereinafter additional embodiments of the combustor triple liner assembly 1 have been explained.
As shown in FIG 4 the inner liner 60 may be a continuous surface without any perforations. Alternatively, as shown in FIG 5 in an embodiment of the combustor triple liner assembly 1, the inner liner 60 includes a plurality of film cooling holes 66. The film cooling holes 66 allow a part of the cooling air 7 from the inner compartments 201,202,203 where the film cooling holes 66 are located, to enter the combustion chamber 28. FIG 7 depicts flow of the part of cooling air 7 through the film cooling holes 66 by arrows marked with reference numeral 67. Furthermore, as also schematically depicted in FIG 5, in another embodiment of the combustor triple liner assembly 1, the inner liner 60 includes at least one dilution hole 68. A size, for example 10 mm to 30 mm and preferably 20 mm in the diameter, of the dilution holes 68 is larger than a size, for example 0.5 mm to 2 mm and preferably 1 mm in the diameter, of the film cooling holes 66. The dilution holes 68 allows a part of the cooling air 7 from the inner compartments 201,202,203 where the dilution hole 68 is located, to enter the combustion chamber 28. FIG 7 also depicts flow of the part of cooling air 7 through the dilution holes 68 by arrows marked with reference numeral 69.
As shown in FIGs 3 and 6, in an exemplary embodiment of the combustor triple liner assembly 1, the outer dividers 93 include one or more by-pass holes 94. The by-pass holes 94 allow a part of the cooling air 7 to flow from the outer compartment 301,302,303 upstream, with respect to the general direction 9 of the flow of the cooling air 7, of the outer divider 93 into the outer compartment 301,302,303 downstream of the outer divider 93, without flowing through any inner compartment 201,202,203. A plurality of the by-pass holes 94 may be circumferentially arranged about the longitudinal axis 35. FIG 7 also depicts flow of the part of cooling air 7 through the by-pass holes 94 by arrows marked with reference numeral 95.
FIGs 8, 9, 10 and 11 schematically illustrate exploded views of different exemplary embodiment of the combustor triple liner assembly 1.
As schematically depicted in FIG 8, in an embodiment of the combustor triple liner assembly 1, the outer dividers 93 are integrally formed with the outer liner 80, i.e. the outer dividers 93 are formed as one part extensions of the outer liner 80. The outer dividers 93 project out, i.e. in radially inward direction with respect to the axis 35, from the inner surface 81 of the outer liner 80. In this embodiment of the combustor triple liner assembly 1, the inner dividers 92 are integrally formed with the middle liner 70, i.e. the inner dividers 92 are formed as one part extensions of the middle liner 70. The inner dividers 92 project out, i.e. in radially inward direction with respect to the axis 35, from the inner surface 71 of the middle liner 70. Thus the combustor triple liner assembly 1 according to this embodiment has only three parts or components i.e. the inner liner 60, the middle liner 70 with the integrally formed inner dividers 92, and the outer liner 80 with the integrally formed outer dividers 93. When assembled, the middle liner 70 is sandwiched between the inner liner 60 and the outer liner 80 such that the inner dividers 92 of the middle liner 70 physically contact the outer surface 62 of the inner liner 60 and the outer dividers 93 of the outer liner 80 physically contact the outer surface 72 of the middle liner 70.
As schematically depicted in FIG 9, in another embodiment of the combustor triple liner assembly 1, the outer dividers 93 are integrally formed with the outer liner 80, i.e. the outer dividers 93 are formed as one part extensions of the outer liner 80. The outer dividers 93 project out, i.e. in radially inward direction with respect to the axis 35, from the inner surface 81 of the outer liner 80. In this embodiment of the combustor triple liner assembly 1, the inner dividers 92 are integrally formed with the inner liner 60, i.e. the inner dividers 92 are formed as one part extensions of the inner liner 60. The inner dividers 92 project out, i.e. in radially outward direction with respect to the axis 35, from the outer surface 62 of the inner liner 60. Thus the combustor triple liner assembly 1 according to this embodiment has only three parts or components i.e. the inner liner 60 with the integrally formed inner dividers 92, the middle liner 70, and the outer liner 80 with the integrally formed outer dividers 93. When assembled, the middle liner 70 is sandwiched between the inner liner 60 and the outer liner 80 such that the inner dividers 92 of the inner liner 60 physically contact the inner surface 71 of the middle liner 70 and the outer dividers 93 of the outer liner 80 physically contact the outer surface 72 of the middle liner 70.
As schematically depicted in FIG 10, in another embodiment of the combustor triple liner assembly 1, the outer dividers 93 are integrally formed with the middle liner 70, i.e. the outer dividers 93 are formed as one part extensions of the middle liner 70. The outer dividers 93 project out, i.e. in radially outward direction with respect to the axis 35, from the outer surface 72 of the middle liner 70. In this embodiment of the combustor triple liner assembly 1, the inner dividers 92 are integrally formed with the inner liner 60, i.e. the inner dividers 92 are formed as one part extensions of the inner liner 60. The inner dividers 92 project out, i.e. in radially outward direction with respect to the axis 35, from the outer surface 62 of the inner liner 60. Thus the combustor triple liner assembly 1 according to this embodiment has only three parts or components i.e. the inner liner 60 with the integrally formed inner dividers 92, the middle liner 70 with the integrally formed outer dividers 93, and the outer liner 80. When assembled, the middle liner 70 is sandwiched between the inner liner 60 and the outer liner 80 such that the inner dividers 92 of the inner liner 60 physically contact the inner surface 71 of the middle liner 70 and the outer dividers 93 of the middle liner 70 physically contact the inner surface 81 of the outer liner 80.
As schematically depicted in FIG 11, in a further embodiment of the combustor triple liner assembly 1, the outer dividers 93 and the inner dividers 92 are integrally formed with the middle liner 70, i.e. the inner dividers 92 and the outer dividers 93 are formed as one part extensions of the middle liner 70. The inner dividers 92 project out, i.e. in radially inward direction with respect to the axis 35, from the inner surface 71 of the middle liner 70 whereas the outer dividers 93 project out, i.e. in radially outward direction with respect to the axis 35, of the outer surface 72 of the middle liner 70. Thus the combustor triple liner assembly 1 according to this embodiment has only three parts or components i.e. the inner liner 60, the middle liner 70 with the integrally formed inner and outer dividers 92,93 and the outer liner 80. When assembled the middle liner 70 is sandwiched between the inner liner 60 and the outer liner 80 so that the inner dividers 92 of the middle liner 70 physically contact the outer surface 62 of the inner liner 60 and the outer dividers 93 of the middle liner 70 physically contact the inner surface 81 of the outer liner 80.
While the present technique has been described in detail with reference to certain embodiments, it should be appreciated that the present technique is not limited to those precise embodiments. Rather, in view of the present disclosure which describes exemplary modes for practicing the invention, many modifications and variations would present themselves, to those skilled in the art without departing from the scope and spirit of this invention. The scope of the invention is, therefore, indicated by the following claims rather than by the foregoing description. All changes, modifications, and variations coming within the meaning and range of equivalency of the claims are to be considered within their scope.

Claims

A combustor triple liner assembly (1) for a gas turbine engine (10), the combustor triple liner assembly (1) comprising:
- an inner liner (60) having a longitudinal axis (35) and defining a combustion chamber (28),

- a middle liner (70) housing the inner liner (60),

- an outer liner (80) housing the middle liner (70) and the inner liner (60),

- wherein the inner liner (60), the middle liner (70) and the outer liner (80) are coaxially aligned cylinders and are radially separated to create an inner annular flow-path (2) between the inner liner (60) and the middle liner (70), and to create an outer annular flow-path (3) between the middle liner (70) and the outer liner (80),

- a plurality of inner dividers (92) serially arranged longitudinally within the inner annular flow-path (2), wherein each of the inner dividers (92) extends radially between the inner liner (60) and the middle liner (70) dividing the inner annular flow-path (2) into a plurality of inner compartments (201,202,203),

- a plurality of outer dividers (93) serially arranged longitudinally within the outer annular flow-path (3), wherein each of the outer dividers (93) extends radially between the middle liner (70) and the outer liner (80) dividing the outer annular flow-path (3) into a plurality of outer compartments (301,302,303) and dividing the middle liner into a plurality of middle liner sections (701,702,703) corresponding to each outer compartment (301,302,303),

- wherein the middle liner section (701,702,703) of each outer compartment (301,302,303) comprises a plurality of impingement holes (75) fluidly connecting the outer compartment (301,302,303) to one corresponding inner compartment (201,202,203) and wherein the corresponding inner compartment (201,202,203) is fluidly connected to one corresponding downstream outer compartment (301,302,303) through at least one opening (77) in the middle liner (70), such that cooling air (7) entering the outer annular flow-path (3) flows from the outer compartment (301,302,303) through the impingement holes (75) of the outer compartment (301,302,303) to the corresponding inner compartment (201,202,203) and therefrom through the opening (77) to the corresponding downstream outer compartment (301,302,303).
The combustor triple liner assembly (1) according to claim 1, wherein the inner liner (60) comprises a plurality of film cooling holes (66) adapted to allow a part of the cooling air (7) from at least one of the inner compartments (201,202,203) to enter the combustion chamber (28) and to provide film cooling of an inner surface (61) of the inner liner (60).
The combustor triple liner assembly (1) according to claim 1 or 2, wherein the inner liner (60) comprises at least one dilution hole (68) adapted to allow a part of the cooling air (7) from at least one of the inner compartments (201,202,203) to enter the combustion chamber (28) to dilute the combustion gases in the combustion chamber (28).
The combustor triple liner assembly (1) according to any of claims 1 to 3, wherein the impingement holes (75) are located in the middle liner section (701,702,703) of each outer compartment (301,302,303) as an array (74) extending circumferentially and axially in the middle liner section (701,702,703).
The combustor triple liner assembly (1) according to any of claims 1 to 4, wherein at least one of the outer dividers (93) comprises one or more by-pass holes (94) configured to allow a part of the cooling air (7) to flow from the outer compartment (301,302,303) upstream of the outer divider (93) to the outer compartment (301,302,303) downstream of the outer divider (93).
The combustor triple liner assembly (1) according to any of claims 1 to 5, wherein the outer dividers (93) are integrally formed with the middle liner (70).
The combustor triple liner assembly (1) according to claim 6, wherein the inner dividers (92) are integrally formed with the middle liner (70).
The combustor triple liner assembly (1) according claims 6, wherein the inner dividers (92) are integrally formed with the inner liner (60).
The combustor triple liner assembly (1) according to any of claims 1 to 5, wherein the outer dividers (93) are integrally formed with the outer liner (80).
The combustor triple liner assembly (1) according to claim 9, wherein the inner dividers (92) are integrally formed with the middle liner (70).
The combustor triple liner assembly (1) according to claim 9, wherein the inner dividers (92) are integrally formed with the inner liner (60).
A combustor assembly (100) comprising a burner (30) and a combustor triple liner assembly (1), wherein the combustor triple liner assembly (1) is according to any of claims 1 to 11.
A gas turbine engine (10) comprising a combustor triple liner assembly (1), wherein the combustor triple liner assembly (1) is according to any of claims 1 to 11.