Abstract:
One embodiment of the present invention is a unique gas turbine engine combustion liner. Another embodiment is a unique gas turbine engine. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for gas turbine engines and gas turbine engine combustion liners. Further embodiments, forms, features, aspects, benefits, and advantages of the present application will become apparent from the description and figures provided herewith.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims benefit of U.S. Provisional Patent Application No. 61/428,810, filed Dec. 30, 2010, entitled GAS TURBINE ENGINE AND COMBUSTION LINER, which is incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to gas turbine engines, and more particularly, to gas turbine engine combustion liners. 
       BACKGROUND 
       [0003]    Gas turbine engine combustion liners that effectively withstand high temperature conditions and provide reduced acoustics remain an area of interest. Some existing systems have various shortcomings, drawbacks, and disadvantages relative to certain applications. Accordingly, there remains a need for further contributions in this area of technology. 
       SUMMARY 
       [0004]    One embodiment of the present invention is a unique gas turbine engine combustion liner. Another embodiment is a unique gas turbine engine. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for gas turbine engines and gas turbine engine combustion liners. Further embodiments, forms, features, aspects, benefits, and advantages of the present application will become apparent from the description and figures provided herewith. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and wherein: 
           [0006]      FIG. 1  schematically illustrates some aspects of a non-limiting example of a gas turbine engine in accordance with an embodiment of the present invention. 
           [0007]      FIG. 2  schematically illustrates some aspects of a non-limiting example of a gas turbine engine combustion liner in accordance with an embodiment of the present invention. 
           [0008]      FIG. 3  schematically illustrates some aspects of a non-limiting example of a liner wall structure in accordance with an embodiment of the present invention. 
           [0009]      FIG. 4  schematically illustrates some aspects of a non-limiting example of another liner wall structure in accordance with an embodiment of the present invention. 
           [0010]      FIG. 5  schematically illustrates some aspects of a non-limiting example of yet another liner wall structure in accordance with an embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0011]    For purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the same. It will nonetheless be understood that no limitation of the scope of the invention is intended by the illustration and description of certain embodiments of the invention. In addition, any alterations and/or modifications of the illustrated and/or described embodiment(s) are contemplated as being within the scope of the present invention. Further, any other applications of the principles of the invention, as illustrated and/or described herein, as would normally occur to one skilled in the art to which the invention pertains, are contemplated as being within the scope of the present invention. 
         [0012]    Referring to the drawings, and in particular  FIG. 1 , there are illustrated some aspects of a non-limiting example of a gas turbine engine  20  in accordance with an embodiment of the present invention. In one form, engine  20  is a propulsion engine, e.g., an aircraft propulsion engine. In other embodiments, engine  20  may be any other type of gas turbine engine, e.g., a marine gas turbine engine, an industrial gas turbine engine, or any aero, aero-derivative or non-aero derivative gas turbine engine. In one form, engine  20  is a two spool engine having a high pressure (HP) spool  24  and a low pressure (LP) spool  26 . In other embodiments, engine  20  may include three or more spools, e.g., may include an intermediate pressure (IP) spool and/or other spools. In one form, engine  20  is a turbofan engine, wherein LP spool  26  is operative to drive a propulsor  28  in the form of a turbofan (fan) system, which may be referred to as a turbofan, a fan or a fan system. In other embodiments, engine  20  may be a turboprop engine, wherein LP spool  26  powers a propulsor  28  in the form of a propeller system (not shown), e.g., via a reduction gearbox (not shown). In yet other embodiments, LP spool  26  powers a propulsor  28  in the form of a propfan. In still other embodiments, propulsor  28  may take other forms, such as one or more helicopter rotors or tilt-wing aircraft rotors. 
         [0013]    In one form, engine  20  includes, in addition to fan  28 , a bypass duct  30 , a compressor  32 , a diffuser  34 , a combustor  36 , a high pressure (HP) turbine  38 , a low pressure (LP) turbine  40 , a nozzle  42 A, a nozzle  42 B, and a tailcone  46 , which are generally disposed about and/or rotate about an engine centerline  48 . In other embodiments, there may be, for example, an intermediate pressure spool having an intermediate pressure turbine. 
         [0014]    In the depicted embodiment, engine  20  core flow is discharged through nozzle  42 A, and the bypass flow is discharged through nozzle  42 B. In other embodiments, other nozzle arrangements may be employed, e.g., a common nozzle for core and bypass flow; a nozzle for core flow, but no nozzle for bypass flow; or another nozzle arrangement. Bypass duct  30  and compressor  32  are in fluid communication with fan  28 . Nozzle  42 B is in fluid communication with bypass duct  30 . Diffuser  34  is in fluid communication with compressor  32 . Combustor  36  is fluidly disposed between compressor  32  and turbine  38 . Turbine  40  is fluidly disposed between turbine  38  and nozzle  42 A. In one form, combustor  36  includes a combustion liner  50  that contains a continuous combustion process. In other embodiments, combustor  36  may take other forms, and may be, for example, a wave rotor combustion system, a rotary valve combustion system, a pulse detonation combustion system or a slinger combustion system, and may employ deflagration and/or detonation combustion processes. 
         [0015]    Fan system  28  includes a fan rotor system  48  driven by LP spool  26 . In various embodiments, fan rotor system  48  includes one or more rotors (not shown) that are powered by turbine  40 . Fan  28  may include one or more vanes (not shown). Bypass duct  30  is operative to transmit a bypass flow generated by fan  28  around the core of engine  20 . Compressor  32  includes a compressor rotor system  50 . In various embodiments, compressor rotor system  50  includes one or more rotors (not shown) that are powered by turbine  38 . Turbine  38  includes a turbine rotor system  52 . In various embodiments, turbine rotor system  52  includes one or more rotors (not shown) operative to drive compressor rotor system  50 . Turbine rotor system  52  is drivingly coupled to compressor rotor system  50  via a shafting system  54 . Turbine  40  includes a turbine rotor system  56 . In various embodiments, turbine rotor system  56  includes one or more rotors (not shown) operative to drive fan rotor system  48 . Turbine rotor system  56  is drivingly coupled to fan rotor system  48  via a shafting system  58 . In various embodiments, shafting systems  54  and  58  include a plurality of shafts that may rotate at the same or different speeds and directions. In some embodiments, only a single shaft may be employed in one or both of shafting systems  54  and  58 . Turbine  40  is operative to discharge the engine  20  core flow to nozzle  42 A. 
         [0016]    During normal operation of gas turbine engine  20 , air is drawn into the inlet of fan  28  and pressurized by fan rotor  48 . Some of the air pressurized by fan rotor  48  is directed into compressor  32  as core flow, and some of the pressurized air is directed into bypass duct  30  as bypass flow. Compressor  32  further pressurizes the portion of the air received therein from fan  28 , which is then discharged into diffuser  34 . Diffuser  34  reduces the velocity of the pressurized air, and directs the diffused core airflow into combustor  36 . Fuel is mixed with the pressurized air in combustor  36 , which is then combusted. The hot gases exiting combustor  36  are directed into turbines  38  and  40 , which extract energy in the form of mechanical shaft power to drive compressor  32  and fan  28  via respective shafting systems  54  and  58 . The hot gases exiting turbine  40  are discharged through nozzle system  42 A, and provide a component of the thrust output by engine  20 . 
         [0017]    Referring to  FIG. 2 , some aspects of a non-limiting example of combustion liner  60  in accordance with an embodiment of the present invention is schematically depicted. Also illustrated are a fuel injector  62  and a swirler  64  employed to create a combustion process within combustion liner  60 . In one form, combustion liner  60  is an annular combustion liner, and includes an outer combustion liner  66  disposed radially around an inner combustion liner  68 . Outer combustion liner  66  terminates at an aft end  66 E. Inner combustion liner  68  terminates at an aft end  68 E. In other embodiments, combustion liner  60  may take other forms. In various embodiments, outer combustion liner  66  and/or inner combustion liner  68  in various locations are formed of one of three types of liner wall structure: a thermally cooled wall section; an acoustically damped wall section; and a thermally cooled and acoustically damped wall section. The type of liner wall structure varies with location along outer combustion liner  66  and/or inner combustion liner  68  in accordance with the need at each location on outer combustion liner  66  and/or inner combustion liner  68  for cooling and for acoustic damping of vibrations arising from the combustion process that is contained within combustion liner  60  during the operation of engine  20 . Thus, some portions of outer combustion liner  66  and inner combustion liner  68  employ a thermally cooled wall section, whereas other portions employ an acoustically damped wall section, and still other portions employ a thermally cooled and acoustically damped wall section. The type of wall section employed may vary along the length of outer combustion liner  66  and inner combustion liner  68 , e.g., in an alternating or other arrangement as between two or three different types of liner wall structure. In some embodiments, only one or two of the aforementioned three types of liner wall structure may be employed, whereas in other embodiments, all three types may be employed. The location along outer combustion liner  66  and inner combustion liner  68  of a particular type of liner wall structure in various embodiments may vary with the needs of the particular application, e.g., depending upon combustion liner temperatures and acoustic characteristics. The locations of the different types of liner wall structures shown in  FIG. 2  by virtue of section lines  3 ,  4  and  5 , from which the cross-sectional schematic illustrations of  FIGS. 3-5  are for illustrative purposes only, and are not intended to limit the location of such liner wall structures in any manner. 
         [0018]    Referring to  FIG. 3  in conjunction with  FIG. 2 , some aspects of a non-limiting example of a thermally cooled wall section  70  in accordance with an embodiment of the present invention are depicted. As illustrated in  FIG. 2 , thermally cooled wall section  70  may be employed at one or more various locations on outer combustion liner  66  and inner combustion liner  68 . Thermally cooled wall section  70  includes an outer combustion liner wall (outer wall)  72 , an inner combustion liner wall (inner wall)  74 , and a cellular structure in the form of a porous open cell foam  76 . In various embodiments, one or more of outer wall  72 , inner wall  74  and open cell foam  76  may also be common with other liner wall structures, e.g., acoustically damped wall section  90  (discussed below with respect to  FIG. 4 ) and thermally cooled and acoustically damped wall section  100  (discussed below with respect to  FIG. 5 ). Open cell foam  76  is disposed between outer wall  72  and inner wall  74 . Outer wall  72  is exposed to diffused compressor discharge air flowing inside combustor  36 , whereas inner wall  74  is exposed to the heat of combustion from the combustion process  78  taking place inside combustion liner  60  during the operation of engine  20 . In one form, outer wall  72  is a structural wall configured to support the balance of the combustion liner  60 , e.g., open cell foam  76  and inner wall  74  of thermally cooled wall section  70 . 
         [0019]    In one form, outer wall  72 , inner wall  74  and open cell foam  76  are formed of a ceramic matrix composite. In other embodiments, one or more of outer wall  72 , inner wall  74  and open cell foam  76  may be formed of one or more other composite, metallic and/or intermetallic materials or other materials. In one form, outer wall  72 , inner wall  74  and open cell foam  76  are formed integrally as a unit, i.e., a unitary structure, e.g., wherein outer wall  72 , inner wall  74  and open cell foam  76  are formed separately and then affixed together, e.g., via bonding or another material joining process to yield a one-piece unitary structure as the end product. In other embodiments, outer wall  72 , inner wall  74  and open cell foam  76  may be formed as a unitary structure by use of a stereolithography process or another freeform or similar such manufacturing process. In still other embodiments, outer wall  72 , inner wall  74  and open cell foam  76  may not be formed as a unitary structure, i.e., outer wall  72 , inner wall  74  and open cell foam  76  may be assembled using mechanical fasteners, interference fits and/or other deformation schemes or the like. 
         [0020]    In one form, outer wall  72  includes a plurality of cooling air supply openings  80  configured to receive cooling air  82  from outside of outer wall  72 . In other embodiments, outer wall may not include cooling air supply openings. In still other embodiments, cooling air may be supplied via other means, e.g., from an end of outer wall  72  adjacent to swirler  64 . Open cell foam  76  is configured to distribute cooling air received from cooling air supply openings  80 . In one form, open cell foam  76  is configured to distribute cooling air  82  along inner wall  74  for convective cooling of inner wall  74 . In other embodiments, open cell foam  76  may not be so configured. In one form, open cell foam  76  is configured to conduct heat away from inner wall  74  and transmit the heat to cooling air  82 . In other embodiments, open cell foam  76  may not be so configured. In one form, in thermally cooled wall section  70 , inner wall  74  includes a plurality of openings  84 . In one form, openings  84  are in fluid communication with open cell foam  76 . In one form, open cell foam  76  is configured to distribute cooling air  82  to openings  84 . Openings  84  are configured to discharge cooling air  82 , e.g., for film cooling of inner wall  74 . 
         [0021]    Referring to  FIG. 4  in conjunction with  FIG. 2 , some aspects of a non-limiting example of an acoustically damped wall section  90  in accordance with an embodiment of the present invention are depicted. As illustrated in  FIG. 2 , acoustically damped wall section  90  may be employed at one or more various locations on outer combustion liner  66  and inner combustion liner  68 . Acoustically damped wall section  90  includes an outer wall, e.g., outer wall  72 , an inner wall, e.g., inner wall  74 , and a cellular structure in the form of an honeycomb  92 . In various embodiments, one or more of outer wall  72 , inner wall  74  and honeycomb  92  may also be common with other liner wall structures, e.g., thermally cooled and acoustically damped wall section  100  (discussed below with respect to  FIG. 5 ). Honeycomb  92  is disposed between outer wall  72  and inner wall  74 . As with thermally cooled wall section  70 , outer wall  72  is exposed to diffused compressor discharge air flowing inside combustor  36 , whereas inner wall  74  is exposed to the heat of combustion from combustion process  78  taking place inside combustion liner  60  during the operation of engine  20 . In one form, outer wall  72  is a structural wall configured to support the balance of the combustion liner  60 , e.g., honeycomb  92  and inner wall  74  of acoustically damped wall section  90 . 
         [0022]    In one form, outer wall  72 , inner wall  74  and honeycomb  92  are formed of a ceramic matrix composite. In other embodiments, one or more of outer wall  72 , inner wall  74  and honeycomb  92  may be formed of one or more other composite, metallic and/or intermetallic materials. In one form, outer wall  72 , inner wall  74  and honeycomb  92  are formed integrally as a unit, i.e., a unitary structure, e.g., wherein outer wall  72 , inner wall  74  and honeycomb  92  may be formed separately and then affixed together, e.g., via bonding or another material joining process to yield a unitary structure as the end product. In other embodiments, outer wall  72 , inner wall  74  and honeycomb  92  may be formed as a unitary structure by use of a stereolithography process or another freeform or similar such manufacturing process. In still other embodiments, outer wall  72 , inner wall  74  and honeycomb  92  may not be formed as a unitary structure, i.e., outer wall  72 , inner wall  74  and honeycomb  92  may be assembled using mechanical fasteners, interference fits and/or other deformation schemes or the like. In one form, outer wall  72  and inner wall  74  are continuous as between thermally cooled wall section  70  and acoustically damped wall section  90 , i.e., extending continuously between sections  70  and  90 . In other embodiments, outer wall  72  and inner wall  74  may be discontinuous as between thermally cooled wall section  70  and acoustically damped wall section  90 . In one form, outer wall  72  and inner wall  74  have a same wall thickness in both thermally cooled wall section  70  and acoustically damped wall section  90 . In other embodiments, outer wall  72  and inner wall  74  may have different thicknesses as between sections  70  and  90 . 
         [0023]    Honeycomb  92  includes a plurality of cells  94 . In acoustically damped wall section  90 , inner wall  74  includes a plurality of openings  96 . In one form, each cell  94  is exposed to an opening  96 . In other embodiments, each cell  94  may be exposed to more than one opening  96 . Cells  94  and openings  96  are configured to acoustically damp vibrations at one or more selected frequencies, e.g., at frequencies associated with the geometry of combustion liner  60  and combustion process  78  and/or other parameters that yield undesirable noise emanating from engine  20  and/or are potentially damaging to one or more engine  20  components. The desired frequencies may be selected by various means, e.g., including component and/or engine testing, vibration analysis, computational fluid dynamics analysis and/or other empirical and/or analytical methods. Various parameters may be controlled in order to achieve a desired acoustic damping, including the size and volume of cells  94 , the size of openings  96 , the thickness of inner wall  74 , as well as other parameters, e.g., the selection of material properties of one or more of outer wall  72 , inner wall  74  and honeycomb  92 . 
         [0024]    In one form, the acoustical damping is effected when a high pressure wave passes through openings  96 , whereby cells  94  absorb at least a portion of the high pressure wave. In some embodiments, the wave energy may be at least partially viscously damped as the wave passes through openings  96 . Then, during a lull in pressure inside combustion liner  60  as the high pressure wave recedes, cells  94  release the higher pressure stored therein, adding the pressure to the trough of the receding wave. Also, in some embodiments, additional viscous damping may be achieved as the dynamic mass flow exits cells  94  via openings  96 . 
         [0025]    Referring to  FIG. 5 , a thermally cooled and acoustically damped wall section  100  is depicted. As illustrated in  FIG. 2 , thermally cooled and acoustically damped wall section  100  may be employed at one or more various locations on outer combustion liner  66  and inner combustion liner  68 . Thermally cooled and acoustically damped wall section  100  includes an outer wall, e.g., outer wall  72 , an inner wall, e.g., inner wall  74 , a layer of a cellular structure in the form of open cell foam  76 , an intermediate wall  102 , and a layer of a cellular structure in the form of honeycomb  92 . Open cell foam  76  and honeycomb  92  are disposed between outer wall  72  and inner wall  74 . In particular, in acoustically damped wall section  100 , open cell foam  76  is disposed between outer wail  72  and intermediate wall  102 ; and honeycomb  92  is disposed between intermediate wall  102  and inner wall  74 . 
         [0026]    As with thermally cooled wall section  70  and acoustically damped wall section  90 , outer wall  72  is exposed to diffused compressor discharge air flowing inside combustor  36 , whereas inner wall  74  is exposed to the heat of combustion from combustion process  78  taking place inside combustion liner  60  during the operation of engine  20 . In one form, outer wall  72  is a structural wall configured to support the balance of the combustion liner  60 , e.g., open cell foam  76 , intermediate wall  102 , honeycomb  92  and inner wall  74  of thermally cooled and acoustically damped wall section  100 . 
         [0027]    In one form, outer wall  72 , open cell foam  76 , intermediate wall  102 , honeycomb  92  and inner wall  74  are formed of a ceramic matrix composite. In other embodiments, one or more of outer wall  72 , open cell foam  76 , intermediate wall  102 , honeycomb  92  and inner wall  74  may be formed of one or more other composite, metallic and/or intermetallic materials. In one form, outer wall  72 , open cell foam  76 , intermediate wall  102 , honeycomb  92  and inner wall  74  are formed integrally as a unit, i.e., a unitary structure, e.g., wherein outer wall  72 , open cell foam  76 , intermediate wall  102 , honeycomb  92  and inner wall  74  are formed separately and then affixed together, e.g., via bonding or another material joining process to yield a unitary structure as the end product. In other embodiments, outer wall  72 , open cell foam  76 , intermediate wall  102 , honeycomb  92  and inner wall  74  may be formed integrally as a unitary structure by use of a stereolithography process or another freeform or similar such manufacturing process. In still other embodiments, outer wall  72 , open cell foam  76 , intermediate wall  102 , honeycomb  92  and inner wall  74  may not be formed as a unitary structure, i.e., outer wall  72 , open cell foam  76 , intermediate wall  102 , honeycomb  92  and inner wall  74  may be assembled using mechanical fasteners, interference fits and/or other deformation schemes or the like. 
         [0028]    In one form, outer wall  72  and inner wall  74  are continuous as between thermally cooled wall section  70 , acoustically damped wall section  90  and thermally cooled and acoustically damped wall section  100 , i.e., extending continuously between sections  70 ,  90  and  100 . In other embodiments, outer wall  72  and inner wall  74  may be discontinuous as between thermally cooled wall section  70 , acoustically damped wall section  90  and thermally cooled and acoustically damped wall section  100 . In one form, outer wall  72  and inner wall  74  have a same wall thickness in thermally cooled wall section  70 , acoustically damped wall section  90  and thermally cooled and acoustically damped wall section  100 . In other embodiments, outer wall  72  and inner wall  74  may have different thicknesses as between sections  70 ,  90  and  100 . 
         [0029]    In one form, in thermally cooled and acoustically damped wall section  100 , outer wall  72  includes a plurality of cooling air supply openings  80  configured to receive cooling air  82  from outside of outer wall  72 . In other embodiments, outer wall  72  may not include cooling air supply openings  80 . The size of openings  80  may vary with location in thermally cooled and acoustically damped wall section  100 , and may vary as with respect to the size of openings  80  in thermally cooled wall section  70 . In still other embodiments, cooling air  82  may be supplied via other means, e.g., from an end of outer wall  72  adjacent to swirler  64 . As with thermally cooled wall section  70 , open cell foam  76  is configured to distribute cooling air received from cooling air supply openings  80 . In one form, open cell foam  76  is configured to distribute cooling air  82  along intermediate wall  102  for convective cooling of intermediate wall  102 . In other embodiments, open cell foam  76  may not be so configured. In one form, open cell foam  76  is configured to conduct heat away from intermediate wall  102  and transmit the heat to cooling air  82 . In other embodiments, open cell foam  76  may not be so configured. Cooling air  82  may be discharged from open cell foam  76  at one or more locations, e.g., openings (not shown) in intermediate wall  102  and/or openings (not shown) in ends  66 E and  68 E. 
         [0030]    As with acoustically damped wall section  90 , honeycomb  92  includes a plurality of cells  94 , and inner wall  74  includes a plurality of openings  96 . Cells  94  are defined by walls  98 . In one form, each cell  94  is exposed to an opening  96 . In other embodiments, each cell  94  may be exposed to more than one opening  96 . Cells  94  and openings  96  are configured to acoustically damp vibrations at one or more selected frequencies, e.g., at frequencies associated with the geometry of combustion liner  60  and combustion process  78  and/or other parameters that yield undesirable noise emanating from engine  20  and/or are potentially damaging to one or more engine  20  components. Various parameters may be controlled in order to achieve a desired acoustic damping, including the size, shape and volume of cells  94 , the size of openings  96 , the thickness of inner wall  74 , as well as other parameters, e.g., the selection of material properties of one or more of outer wall  72 , open cell foam  76 , intermediate wall  102 , honeycomb  92  and inner wall  74 . The size volume of cells  94 , and the size and shape of openings  96  in thermally cooled and acoustically damped wall section  100  may vary as with respect to cells  94  and openings  96  in acoustically damped wall section  90 . The acoustical damping may be obtained in thermally cooled and acoustically damped wall section  100  in the same manner as acoustically damped wall section  90 . 
         [0031]    Embodiments of the present invention include a combustion liner, comprising: an outer combustion liner wall; an inner combustion liner wall; and a cellular structure disposed between the outer combustion liner wall and the inner combustion liner wall, wherein at least one of the outer combustion liner wall and the inner combustion liner wall includes a plurality of openings extending therethrough. 
         [0032]    In a refinement, the cellular structure is formed of a composite material. 
         [0033]    In another refinement, the composite material is a ceramic matrix composite. 
         [0034]    In yet another refinement, the outer combustion liner wall, the inner combustion liner wall and the cellular structure are formed of one or more composite materials. 
         [0035]    In still another refinement, the one or more composite materials includes a ceramic matrix composite. 
         [0036]    In yet still another refinement, the outer combustion liner wall, the inner combustion liner wall and the cellular structure are formed as a unitary structure. 
         [0037]    In a further refinement, the inner combustion liner wall includes the plurality of openings; wherein the cellular structure is a honeycomb formed of a plurality of cells exposed to the plurality of openings; and wherein the plurality of cells and the plurality of openings are configured to acoustically damp vibrations at one or more selected frequencies. 
         [0038]    In a yet further refinement, the outer combustion liner wall includes the plurality of openings in the form of cooling air supply openings; and wherein the cellular structure is an open cell foam configured to distribute cooling air received from the cooling air supply openings. 
         [0039]    In a still further refinement, the inner combustion liner wall includes an other plurality of openings configured to discharge cooling air received from the open cell foam. 
         [0040]    In a yet still further refinement, the cellular structure varies in nature as between different locations about the combustion liner; wherein the cellular structure is in the form of an open cell foam configured to distribute cooling air at one or more locations on the combustion liner; and wherein the cellular structure forms at least part of an acoustic damper configured to acoustically damp vibrations at one or more selected frequencies at another one or more locations on the combustion liner. 
         [0041]    In an additional refinement, the acoustic damper includes the cellular structure in the form of a honeycomb. 
         [0042]    In another additional refinement, the cellular structure includes a layer of open cell foam and a layer of the at least part of the acoustic damper at a same location of the combustion liner. 
         [0043]    In yet another additional refinement, the combustion liner further comprises an intermediate wall disposed between the honeycomb and the open cell foam. 
         [0044]    Embodiments of the present invention include a combustion liner, comprising: an outer combustion liner wall having a cooling air supply opening therein; a porous open cell foam positioned disposed in fluid communication with the cooling air supply opening; and an inner combustion liner wall, wherein the open cell foam is configured to distribute cooling air received from the cooling air supply openings. 
         [0045]    In a refinement, the inner combustion liner wall includes a plurality of openings configured to discharge cooling air received from the open cell foam. 
         [0046]    In another refinement, the inner combustion liner wall includes a plurality of openings; further comprising a honeycomb disposed between the inner combustion liner wall and the outer combustion liner wall; wherein the honeycomb includes a plurality of cells in fluid communication with the plurality of openings; wherein the plurality of cells and the plurality of openings are configured to acoustically damp vibrations at one or more selected frequencies in the combustion liner. 
         [0047]    In yet another refinement, the combustion liner further comprises an intermediate wall disposed between the open cell foam and the honeycomb. 
         [0048]    In still another refinement, the outer combustion liner wall, the open cell foam, the honeycomb and the inner combustion liner wall are formed integrally as a unit. 
         [0049]    In yet still another refinement, the outer combustion liner wall, the open cell foam and the inner combustion liner wall are formed integrally as a unit. 
         [0050]    In a further refinement, the outer combustion liner wall is a structural wall configured to support the balance of the combustion liner. 
         [0051]    Embodiments of the present invention include a gas turbine engine, comprising: a compressor; a combustor in fluid communication with the compressor; and a turbine in fluid communication with the combustor, wherein the combustor includes a combustion liner includes an outer combustion liner wall; an inner combustion liner wall; means for cooling the combustion liner disposed between the outer combustion liner wall and the inner combustion liner wall; and means for acoustically damping vibrations disposed between the outer combustion liner wall and the inner combustion liner wall. 
         [0052]    While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment(s), but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as permitted under the law. Furthermore it should be understood that while the use of the word preferable, preferably, or preferred in the description above indicates that feature so described may be more desirable, it nonetheless may not be necessary and any embodiment lacking the same may be contemplated as within the scope of the invention, that scope being defined by the claims that follow. In reading the claims it is intended that when words such as “a,” “an,” “at least one” and “at least a portion” are used, there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim. Further, when the language “at least a portion” and/or “a portion” is used the item may include a portion and/or the entire item unless specifically stated to the contrary.