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Title:
AIR-COOLED COMPONENT FOR TURBINE ENGINE, WITH MONOLITHIC, VARYING DENSITY, THREE-DIMENSIONAL LATTICE
Document Type and Number:
WIPO Patent Application WO/2018/144065
Kind Code:
A1
Abstract:
An air-cooled component for a combustion turbine, having a monolithic, three-dimensional lattice structure (250) of selectively oriented metallic webs (212, 214, 216) with locally varying lattice density, and asymmetrical- and serpentine-shaped passages (220, 222, 224) formed between the metallic webs for receiving compressed cooling air. The component lattice structure locally varies one or more of lattice density, or cooling airflow rate, or flow volume or flow direction throughout its three-dimensional volume, for locally varying heat transfer and/or vibration damping properties of the component. The lattice structure is incorporated into any one or more of a combustor, or an exhaust, or a transition, or a nozzle, or a liner heatshield, or a tile, or a seal, or an impingement plate, or a liner, or a chute, or a damper, or a ring, or a baffle, or a vane, or a vane ring of a combustion turbine engine.

Inventors:
BOURQUE GILLES (CA)
BOURGEOIS GENEVIEVE (CA)
SANCHEZ FABIAN (CA)
Application Number:
PCT/US2017/044827
Publication Date:
August 09, 2018
Filing Date:
August 01, 2017
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
SIEMENS AG (DE)
International Classes:
F23R3/00
Domestic Patent References:
WO2014105108A12014-07-03
Foreign References:
EP2977679A12016-01-27
US4719748A1988-01-19
GB783521A1957-09-25
US20160370008A12016-12-22
US20080080979A12008-04-03
US20070275210A12007-11-29
US20060153685A12006-07-13
EP2818645A12014-12-31
US20110262695A12011-10-27
Other References:
None
Attorney, Agent or Firm:
KUPSTAS, Tod A. (US)
Download PDF:
Claims:
CLAIMS

What is claimed is:

1. An air-cooled component for a combustion turbine engine, comprising a monolithic, three-dimensional lattice structure of selectively oriented metallic webs with locally varying lattice density, and asymmetrical- and serpentine-shaped passages formed between the metallic webs for receiving compressed cooling air, structure within said component modifying locally one or more of lattice density, or cooling air flow rate, or flow volume or flow direction throughout the three- dimensional volume thereof, for locally varying heat transfer or vibration damping properties of the component.

2. The component of claim 1, further comprising a first face for fluid communication with a compressed source of cooling air, and a second face, opposing the first face, the metallic webs and passages formed therein modifying locally one or more of lattice density, or cooling air flow rate, or flow volume or flow direction within the component, parallel to or between the first and second faces.

3. The component of claim 2, the passages formed therein forming cooling air channels, for direct communication with the compressed source of cooling air through the first face or between the first and second faces.

4. The component of claim 3, the cooling air channels having locally varying cross sections within the component.

5. The component of claim 1, further comprising a first face for fluid communication with a compressed source of cooling air, and a second face, opposing the first face, the metallic webs and passages formed therein modifying locally one or more of lattice density, or cooling air flow rate, or flow volume or flow direction within the component through the first and/or second faces.

6. The component of claim 5, the first face defining a locally varying array of impingement cooling holes, respectively having one or more of non-cylindrical profiles, or angular orientation relative to the first face, or pattern array, or pitch density, in communication with the passages of the three-dimensional lattice structure, for entry of compressed cooling air into the passages of the lattice structure.

7. The component of claim 5, the second face defining a locally varying array of effusion cooling holes, respectively having one or more of non-cylindrical profiles, or angular orientation relative to the second face, or pattern array, or pitch density, in communication with the passages of the three-dimensional lattice structure, for exhaust of compressed cooling air, which provides convective cooling along one or more of said effusion cooling holes, and/or a film of cooling air along an outer-facing surface of the second face.

8. The component of claim 5, further comprising an external, second lattice of metallic webs projecting outwardly from the first face and/or the second face, in a locally varying array, structure of said external, second lattice modifying one or more of external, second lattice density, or cooling air flow rate, or flow volume or flow direction along the respective first and/or second face, for locally varying heat transfer or vibration damping properties of the component.

9. The component of claim 5, the first face, or the second face, or both of the first and second faces coupled to a contiguous, corresponding first or second planar metallic sheet, said corresponding metallic sheet or sheets having apertures formed therein, in communication with the passages of the three-dimensional lattice structure, for transport of cooling air there through.

10. The component of claim 9, further comprising an external, second lattice of metallic webs projecting outwardly from outer facing surfaces of the first and/or the second planar metallic sheet, in a locally varying array, structure of said external, second lattice modifying one or more of external, second lattice density, or cooling air flow rate, or flow volume or flow direction along the respective first and/or second face, for locally varying heat transfer or vibration damping properties of the component.

11. The component of claim 1, further comprising the monolithic, three- dimensional lattice structure of selectively oriented metallic webs, and asymmetrical- and serpentine-shaped passages formed by an additive manufacture process.

12. The component of claim 1, incorporated within any one or more of a combustor, or an exhaust, or a transition, or a nozzle, or a liner heatshield, or a tile, or a seal, or an impingement plate, or a liner, or a chute, or a damper, or a ring, or a baffle, or a vane, or a vane ring of a combustion turbine engine.

13. A combustion turbine engine, comprising:

compressor, combustion, and turbine section stages, the combustion section, including:

an air intake plenum, receiving compressed air from the compressor section;

a fuel delivery system, for delivering fuel;

a combustion chamber, coupled to the air intake plenum and the fuel delivery system, for combusting fuel provided by a fuel delivery system and compressed air provided by the compressor section, and for exhausting combustion gas; and

a transition coupled to the combustion chamber and the turbine section, for directing exhausted combustion gas out of the combustion section into the turbine section;

and at least one component in the combustion section and/or in the turbine section including an air-cooled panel, having a monolithic, three-dimensional lattice structure of selectively oriented metallic webs with locally varying lattice density, and asymmetrical- and serpentine-shaped passages formed between the metallic webs, for receiving compressed cooling air from the compressor section, structure within said panel modifying one or more of lattice density, or cooling air flow rate, or flow volume or flow direction throughout the three-dimensional volume thereof, for locally varying heat transfer or vibration damping properties of the panel.

14. The air-cooled panel of the engine of claim 13, further comprising a first face for fluid communication with the compressed cooling air, and a second face, opposing the first face, the metallic webs and passages formed therein locally modifying one or more of lattice density, or cooling air flow rate, or flow volume or flow direction within the panel, parallel to, or between, or through the first and second faces.

15. The air-cooled panel of the engine of claim 14, the metallic webs projecting outwardly from the first face and/or the second face, in a locally varying, external, second lattice array, structure of said external, second lattice modifying one or more of external, second lattice density, or cooling air flow rate, or flow volume or flow direction along the respective first and/or second face, for locally varying heat transfer or vibration damping properties of the panel.

16. The air-cooled panel of the engine of claim 14, the first face defining a locally varying array of impingement cooling holes, and/or the second face defining a locally varying array of effusion cooling holes, any of said holes having respective non- cylindrical profiles, or angular orientation relative to its respective first or second face, or pattern array or pitch density, in communication with the passages of the three-dimensional lattice structure, for transport of compressed cooling air through said holes.

17. The air-cooled panel of the engine of claim 14, the first face, or the second face, or both of the first and second faces coupled to a contiguous, corresponding first or second planar metallic sheet, said corresponding metallic sheet or sheets having apertures formed therein, in communication with the passages of the three- dimensional lattice structure, for passage of cooling air there through.

18. The air-cooled panel of the engine of claim 13, comprising the monolithic, three-dimensional lattice structure of selectively oriented metallic webs, and asymmetrical- and serpentine-shaped passages formed by an additive manufacture process.

19. The air-cooled panel of the engine of claim 13, incorporated within any one or more of a combustor, or an exhaust, or a transition, or a nozzle, or a liner heatshield, or a tile, or a seal, or an impingement plate, or a liner, or a chute, or a damper, or a ring, or a baffle, or a vane, or a vane ring of a combustion turbine engine.

20. A method for modifying operating temperature within a combustion turbine engine, comprising:

modeling structure of a combustion turbine engine, including compressor, combustion and turbine section stages, and the combustion section including:

an air intake plenum, receiving compressed air from the compressor section;

a fuel delivery system, for delivering fuel;

a combustion chamber, coupled to the air intake plenum and the fuel delivery system, for combusting fuel provided by a fuel delivery system and compressed air provided by the compressor section, and for exhausting combustion gas; and

a transition coupled to the combustion chamber and the turbine section, for directing exhausted combustion gas out of the combustion section into the turbine section; and

a first air-cooled component in the combustion section and/or in the turbine section, having a monolithic, three-dimensional lattice structure of selectively oriented metallic webs with locally varying lattice density, and asymmetrical- and serpentine-shaped passages formed between the metallic webs, for receiving compressed cooling air from the compressor section;

simulating flow of fuel, air, fuel and air mixture, and combustion gas in at least the combustion and turbine sections of the modeled combustion engine, and determining localized temperature or vibration damping in a first location therein; modeling structure of a second air-cooled component in the same combustion turbine engine, by selectively altering in the modeled, first air-cooled component, the three-dimensional lattice structure of selectively oriented metallic webs and passages formed between the metallic webs, for modifying one or more of lattice density, or cooling air flow rate, or flow volume or flow direction throughout the three- dimensional volume thereof, and determining whether the modeled, second air-cooled component achieves a better desired localized temperature or vibration damping at the first location than the modeled, first air-cooled component;

storing the model of the second air-cooled component; and

fabricating a combustion turbine engine, incorporating the modeled, second air-cooled component, if it achieves a better-desired localized temperature or vibration damping at the first location than the modeled, first air-cooled component.

Description:
AIR-COOLED COMPONENT FOR TURBINE ENGINE, WITH

MONOLITHIC, VARYING DENSITY, THREE-DIMENSIONAL LATTICE

PRIORITY CLAIM

[0001] This application claims priority under International Application serial number PCT/US 17/ 16420, entitled "COMBUSTOR WITH THREE-DIMENSIONAL LATTICE PREMIXER", and International Application serial number PCT/US 17/16391, entitled "METHOD FOR NORMALIZING FUEL- AIR MIXTURE WITHIN A COMBUSTOR" , both filed on February 3, 2017, which are incorporated by reference herein.

TECHNICAL FIELD

[0002] The disclosure relates to air-cooled components for combustion or gas turbine engines. More particularly, the disclosure relates to locally-varying density, porous, air-cooled components, such as combustors, exhausts, transitions, nozzles, liner heat shields, tiles, seals, impingement plates, liners, chutes, dampers, rings, baffles, vanes and vane rings, for use in compressor, combustion, turbine and exhaust sections of combustion or gas turbine engines. Some embodiments of these air-cooled components incorporate impingement- and/or effusion-cooling panels, having varying density, porous, monolithic, three-dimensional lattice structures of selectively oriented metallic webs, and asymmetrical- and serpentine-shaped passages. In some embodiments, these webs have locally varying lattice density. Some embodiments of such components incorporate cooling air inlet and/or outlet holes. Metallic web density, as well as pore properties between the webs, control and regulate compressed cooling airflow rate, velocity, volume, and direction. In some embodiments, the air- cooled panels are useful for regulating engine operating temperature, and/or vibration, and/or structural integrity of the panel component, by locally varying the web density and cooling airflow properties, through local "porosity" variations in the lattice structure interstices between the webs. Embodiments in this disclosure are related to methods for making air-cooled panels and modifying web density/passage porosity of their structure locally, to achieve desired temperature, and/or vibration regulation within an engine, and/or for altering structural properties of the panel.

BACKGROUND

[0003] Emission level requirements, established for industrial combustion or gas turbine engines, limit the quantity of oxide of nitrogen (NOx) and other combustion gases produced during engine operation. A known way to reduce emissions of nitrogen oxides is to reduce the combustion reaction temperature. Air/fuel mixture, combustion gas, and compressed cooling airflows within an engine can induce or cause transient and steady state changes in engine vibration and temperature. It is desirable to control and regulate engine temperature, as well as vibration, for engine operating efficiency, reduced emissions, reliability, and increased service life. Some engine components are air cooled by bleeding a portion of compressed air generated by the engine compressor, which would otherwise be supplied for the air/fuel mixture. Precise regulation and efficient use of compressed cooling air bleed allows allocation of more compressed air for combustion control, which improves engine emissions and operating efficiency.

[0004] One problem associated with gas turbine engines is caused by pressure and flow rate temporal fluctuations in either one or both of the compressed air sources feeding the combustor premixer, or combustion gas generated within the combustion chamber and flowing down stream into the turbine section of the engine. Pressure fluctuations in the compressed air supply and/or combustion gas flow through the engine locally disrupt at different times the fuel-air ratio, which adversely influences engine emissions. Extreme temporal pressure and flow fluctuations, whether coupled or uncoupled, may lead to severe damage, or failure, of components if the frequency of the pressure fluctuations coincides with the natural frequency of a vibration mode of one or more of the engine components. It is desirable to have reserve capacity of compressed air to smooth temporal fluctuations in the air-fuel ratio. However, reserve compressed air is also needed for component cooling fluctuations. Compressed air supply allocation for combustion and cooling air bleed is regulated during engine operation. Air supply allocation is compounded by both temporal fluctuations in engine combustion temperature and resultant heating of internal engine components. In addition to temporal fluctuations, there are local temperature variations within the engine, caused by non-uniform flow of compressed air within the engine volume. The following description of non-uniform, compressed air flow in industrial gas turbine engines highlights challenges faced in maintaining localized and temporal airflow uniformity.

[0005] Referring to FIGS. 1 and 2, an industrial gas turbine engine 20, comprises in axial flow series an inlet 22, a compressor section 24, a combustion section 26 (also sometimes referred to as a combustion chamber assembly), a turbine section 28, a power turbine section 30 and an exhaust 32. The compressor section includes rotating compressor blades 25 A, which are circumscribed by a compressor ring segment 25B. The turbine section 28 includes stationary vanes 27A, which are inscribed by vane ring segment 27B, and rotating turbine blades 29A, which are circumscribed by a turbine ring segment 29B. The rotating turbine blades 29 A are arranged to drive the compressor blades 25A in the compressor section 24, via one or more shafts (not shown). The power turbine section 30 is arranged to drive an electrical generator 36 via a shaft 34.

[0006] The combustion section 26 comprises a plurality of equally circumferentially spaced combustors 38. Longitudinal axes of the combustors 38 are arranged to extend in generally radial directions. The inlets of the combustors 38 are at their radially outermost ends and their outlets are at their radially innermost ends. The casing of the combustion section 26 incorporates an air intake plenum, which is in communication with the compressor section compressed air output, for providing compressed air to the inlets of the combustors 38. Combustion gas generated within the combustor 38 flows through a corresponding transition 39, and thereafter into the turbine section 28. Known combustor designs include, without limitation, so-called can, annular, and can-annular designs. Each of the combustors has a premixer, which receives compressed air from an air intake plenum that is in communication with the engine's compressor, and fuel from a fuel delivery system. The premixer has a fuel and air- mixing duct, which mixes the fuel and air at a desired fuel-air ratio and transfers the mixture, via a fuel and air discharge duct, into a combustion zone of the combustion chamber. In multi-stage combustors, respective secondary, and in some embodiments tertiary, fuel and air mixing ducts supply a mixture of fuel and air into secondary or tertiary combustion zones, via respective fuel and air discharge ducts.

[0007] An exemplary known, can-type, three-stage combustor 40 is shown in FIG 2. The combustor 40 includes a combustor outer casing 42, which receives compressed air CP from the compressor section 24 via an air intake 44. An annular air intake plenum 46 is defined between the interior of the combustor outer casing 42 and a fuel- air premixer assembly ("premixer assembly") 47. The premixer assembly 47 receives compressed air from the air intake plenum 46 and fuel from a fuel delivery system 48, in respective fuel and air mixing ducts ("FAMDs") 49A, 49B and 49C. In the FAMDs, the fuel and air are combined into a fuel and air mixture, which discharges into a combustion chamber 50.

[0008] The combustion chamber 50 is stepped, the upper axial end of which is defined by an upstream wall 51. The upstream wall 51 defines an upstream axial limit of a primary combustion zone 52, and a primary annular wall 53 defines a circumferential axial limit of the primary combustion zone. A secondary combustion zone 54 is circumferentially defined by a secondary annular wall 55, downstream of the primary combustion zone 52. A tertiary combustion zone 56 is circumferentially defined by a tertiary annular wall 57, downstream of the secondary combustion zone 54. The transition 39 is coupled to, and in fluid communication with the tertiary annular wall 57 of the combustion chamber 50.

[0009] As fuel is delivered via the fuel delivery system 48 to the premixer 47 at relatively higher pressure than that of the supplied compressed air CP, fuel flow rate does not significantly fluctuate. However, the compressed air CP and combustion backpressure BP do fluctuate temporally denoted as ACP and ΔΒΡ in FIG. 2, leading to temporal fluctuations in the fuel-air ratio. In some known embodiments, metal foam blocks, containing sponge-like, randomly distributed interstices or pores, are incorporated in fuel and air mixing ducts of the premixer 47, in order to normalize pulsations within the airflow.

[0010] Localized, steady state, variations in compressed airflow CP within the air intake plenum 46, or combustion backpressure BP in the combustion chamber 50, influence the corresponding localized fuel-air ratio within the premixer assembly 47. Due to such localized variations in compressed airflow CP and combustion backpressure BP, different circumferential position within the premixer assembly 47, can generate different fuel-air ratio mixtures, notwithstanding the overall goal of equalizing fuel-air ratio mixtures in the respective FAMDs 49A, 49B, and 49C. Assuming that uniform fuel-air ratios are fed into the combustion chamber 50, combusted gasses within the combustion chamber also exhibit local variations in the combusted fuel and air mixture.

[0011] The high operating temperatures within a combustion turbine engine 20 require air flow cooling of engine components, by bleeding a portion of the compressed air CP generated by the engine compressor section 24. Cooling methods employed in such engine components include by way of non-limiting example convection, impingement, and transpiration. Components that are facing combustion flames and combustion gasses employ compressed air cooling to meet service life targets. Exemplary components which are exposed to combustion flames and gasses include the combustors 38 or 40, or the exhaust 32, or the transitions 39, the vanes 27A and their vane rings 27B, turbine ring segments 29B or combustion chambers 50, or nozzles, or liner heatshields, or tiles, or seals, or impingement plates, or liners, or chutes, or dampers, or baffles. In the past, bonded panels have been employed to provide both impingement and effusion cooling of engine components that are exposed to combustion flames and gasses, such as transitions 39 and combustion chambers 50. An air-cooled component, such as transition 39 or the combustion chamber 50, experiences localized temperature variations on its surfaces that are exposed to hot combustion gas. Sufficient compressed air CP mass flow needs to be supplied to the air-cooled component to maintain all of the component surfaces within specified temperature limits, in order to avoid localized thermal failure. However, other portions of the component hot surfaces may not have the same compressed air mass flow needs. Past attempts to modify locally cooling-air flow properties within air-cooled engine components have had limited success.

[0012] FIGs. 3 and 4 show a known sandwich-like construction, bonded panel 60, which is also referred to as a transply, or a lamalloy panel, in which compressed air CP impinges upon a an exterior surface 62 of a cold side 64 of the panel, enters inlet impingement holes or apertures 66 formed within the cold side of the panel. The compressed air CP travels laterally and transversely through internal cooling channels 68, where it impinges upon a hot side 70 of the panel 60. In the embodiment shown in FIGs. 3 and 4, exhaust effusion holes or apertures 72 exhaust or expel cooling air out of an exterior facing surface 74 of the hot side 70 of the panel 60. In some embodiments, the exhaust effusion holes 72 have cross-sectional areas, profiles, pitch, and surface location that are sized as diffusion holes to provide film cooling to the exterior facing surface 74 of the hot side 70 of the diffusion panel 60.

[0013] The bonded panels 60 are typically constructed by chemically eroding, cutting, or ablating the apertures 66 or 72 through their respective metal sheets 64 and 70 that form, respectively, the cold and hot sides of the panel. The respective metal sheets 64 and 70 are of uniform thickness. The internal cooling channels 68 are formed by chemical erosion, cutting, or ablation of the inner, facing surfaces of those metal sheets. Then, the opposed metal sheets that form the cold 64 and hot 70 sides of the panel are joined together, typically by diffusion bonding the opposed, inner facing surfaces together. The now bonded sheets form the impingement-effusion cooling panel 60. The flat panel 60 is capable of being rolled into shapes, such as circumferential walls of the exhaust 32, the rings 25B, 27B, or 29B, the transition 39, and stepped, annular surfaces 53, 55, 57 of the combustion chamber 50.

[0014] Formation of cooling apertures 66 or 72 and channels 68 in the known construction, bonded panels 60 is complex. Aperture and channel cross-sectional and longitudinal dimensions, their spacing and topology is limited to what can be formed into the flat sheets that form the cold 64 and hot 70 sides. Generally, the topology of the channel 68 and the apertures 66, 72 are symmetrical. In some embodiments, cross-sectional profile of apertures 66 and 72 is non-circular, but limited to what can be cut or ablated by known machining and lithography techniques.

SUMMARY

[0015] Air-cooled components for a combustion turbine engine, including by way of non-limiting example, air-cooled panels, include a lattice structure for cooling-air flow, which in some embodiments facilitates localized variations in heat transfer and/or vibration damping properties of the component. An exemplary, air-cooled component has a monolithic, three-dimensional lattice structure of selectively oriented metallic webs, and asymmetrical- and serpentine-shaped passages formed between the metallic webs for receiving compressed cooling air. In some embodiments, the component lattice structure locally varies one or more of lattice density or cooling air flow rate, or flow volume or flow direction throughout its three-dimensional volume.

[0016] In some embodiments, localized variations within the volume of the component's outer surfaces and lattice structure locally vary heat transfer and/or vibration damping properties of the component, which conserves cooling-air mass flow. By optimizing cooling-air mass flow, through localized structure variations within the component volume, the component operates within defined temperature and vibration damping specifications— extending potential service life of the component— while minimizing air-bleed mass flow from the compressor. Localized optimization of the cooling airflow within the engine component, such as an air- cooled panel portion of a component, potentially reduces cooling-air bleed requirements, leaving more compressed air available for combustion gas fuel-air, mass-flow regulation. The three-dimensional, lattice structure is incorporated into any one or more of a combustor, or an exhaust, or a transition, or a nozzle, or a liner heatshield, or a tile, or a seal, or an impingement plate, or a liner, or a chute, or a damper, or a ring, or a baffle, or a vane, or a vane ring, or any other air-cooled component of a combustion turbine engine. [0017] In the aforementioned International Application serial number PCT/US 17/ 16420, entitled "COMBUSTOR WITH THREE-DIMENSIONAL LATTICE PREMIXER", and International Application serial number PCT/US 17/16391, entitled "METHOD FOR NORMALIZING FUEL- AIR MIXTURE WITHIN A COMBUSTOR" , both filed on February 3, 2017, the premixer embodiments described therein locally vary structure of one or more of air ducts, fuel delivery passages, fuel and air mixing ducts, and/or fuel and air discharge ducts, in order to normalize fuel-air ratio at any location about the premixer' s three- dimensional volume or in the combustion chamber, in response to any one or more of the following operational conditions: (a) during steady-state operation without temporal fluctuations in (i) compressed air supply to the premixer, or (ii) combustion gas backpressure upstream into the premixer, or (iii) combustion mass flow within the combustor; and/or (b) in order to stabilize fluctuations in compressed air supply to the premixer, and/or (c) in order to stabilize fluctuations in combustion gas backpressure upstream into the premixer; and/or (d) in order to stabilize combustion mass flow within the combustor. In those embodiments, the premixer is a monolithic, three- dimensional lattice structure of selectively oriented metallic webs, and asymmetrical- and serpentine-shaped passages formed in the interstices between the webs.

[0018] In the premixer and air-cooled component (including air-cooled panel) embodiments described herein, the spaces or interstices between the webs within the three-dimensional lattice define locally varying passages, which form: the aforementioned cooling passages, air ducts, fuel ducts, fuel delivery passages, fuel and air mixing ducts, and fuel and air discharge ducts. In some embodiments, the air- cooled component, or the premixer, or a casting mold for the air-cooled component or premixer, is formed by additive manufacture. Additive manufacture processes facilitate formation of complex webs and passages within the air-cooled component or the premixer that are not possible to manufacture by traditional solid metal fabrication, metal cutting, or metal casting methods.

[0019] In other embodiments, premixers and air-cooled components are modeled virtually in simulated operational engines. The three-dimensional lattice structures of such exemplary components are selectively varied, in order to simulate regulation and/or normalization of any one or more of temperature, vibration damping, cooling- air flow, or fuel-air ratio, which is relevant to operation and function of that component, at any location about its three-dimensional volume, during steady-state operating conditions. In some embodiments, local variances in the three-dimensional lattice structures in the exemplary components are made, in order to stabilize temporal fluctuations in compressed air supply to the relevant component, and/or in order to stabilize fluctuations in combustion gas backpressure upstream into the premixer, and/or to stabilize mass flow and pressure fluctuations in combustion gas within the combustor's combustion chamber. In these exemplary embodiments, the air-cooled component and/or the premixer is a monolithic, three-dimensional lattice structure of selectively oriented metallic webs, and asymmetrical- and serpentine-shaped passages formed in the spaces or interstices between the webs, for regulating and/or normalizing compressed air flow.

[0020] Lattice web density, cavity profiles, orientation, and flow direction of any one, or more, or all of the respective air-cooling channels in the air-cooled components, such as air-cooled panels, vary locally within the three-dimensional lattice structure, in order to modify locally the heat transfer, vibration damping, and structural properties of the component. Thus, local variations in the three-dimensional lattice structure compensate for local temperature and/or vibration properties about the air- cooled component, leading to more locally- and temporally-uniform temperature distributions within the engine, below specified temperature limits, enhancing engine service life. Local variation in the air-cooled component's lattice structure minimizes use of cooling-air bleed from the compressor section, leaving more of the compressed air available for engine combustion and resultant, higher engine operating efficiency.

[0021] Exemplary embodiments of the invention feature an air-cooled component for a combustion turbine engine, having a monolithic, three-dimensional lattice structure of selectively oriented metallic webs with locally varying lattice density, and asymmetrical- and serpentine-shaped passages formed between the metallic webs for receiving compressed cooling air. The air-cooled component structure modifies locally one or more of lattice density, or cooling airflow rate, or flow volume or flow direction throughout its three-dimensional volume, for locally varying heat transfer or vibration damping properties of the component.

[0022] Other exemplary embodiments of the invention feature a combustion turbine engine, including compressor, combustion, and turbine section stages. The combustion section includes: an air intake plenum, receiving compressed air from the compressor section, a fuel delivery system, for delivering fuel, a combustion chamber, coupled to the air intake plenum and the fuel delivery system, for combusting fuel provided by a fuel delivery system and compressed air provided by the compressor section, and for exhausting combustion gas. A transition is coupled to the combustion chamber and the turbine section, for directing exhausted combustion gas out of the combustion section into the turbine section. At least one component in the combustion section and/or in the turbine section of the engine includes an air-cooled panel, having a monolithic, three-dimensional lattice structure of selectively oriented metallic webs with locally varying lattice density. Asymmetrical- and serpentine- shaped passages are formed between the metallic webs, for receiving compressed cooling air from the compressor section. Web structure within the panel modifies one or more of lattice density, or cooling airflow rate, or flow volume or flow direction throughout its three-dimensional volume, for locally varying heat transfer or vibration damping properties of the panel.

[0023] Additional exemplary embodiments of the invention feature a method for modifying operating temperature within a combustion turbine engine. The method is practiced by modeling structure of a combustion turbine engine, including compressor, combustion and turbine section stages, and the combustion section including. The modeled engine includes: an air intake plenum, receiving compressed air from the compressor section; a fuel delivery system, for delivering fuel; a combustion chamber, coupled to the air intake plenum and the fuel delivery system, for combusting fuel provided by a fuel delivery system and compressed air provided by the compressor section, and for exhausting combustion gas; and a transition coupled to the combustion chamber and the turbine section, for directing exhausted combustion gas out of the combustion section into the turbine section. The modeled components also include a first air-cooled component in the combustion section and/or in the turbine section, having a monolithic, three-dimensional lattice structure of selectively oriented metallic webs with locally varying lattice density, and asymmetrical- and serpentine-shaped passages formed between the metallic webs, for receiving compressed cooling air from the compressor section. Flow of fuel, air, fuel and air mixture, and combustion gas is simulated in at least the combustion and turbine sections of the modeled combustion engine. Localized temperature or vibration damping properties in a first location therein are simulated. Structure of a second air-cooled component is modeled in the same combustion turbine engine, by selectively altering in the modeled, first air-cooled component, its three-dimensional lattice structure of selectively oriented metallic webs and passages formed between the metallic webs. The modeled, second, air-cooled component structure modifies one or more of lattice density or cooling air flow rate, or flow volume or flow direction throughout the three-dimensional volume thereof. It is then determined whether the modeled, second air-cooled component achieves a better desired localized temperature or vibration damping at the first location than the modeled, first air- cooled component. The model of the second air-cooled component is stored. A combustion turbine engine, incorporating the modeled, second air-cooled component, is fabricated, if it achieves a better-desired localized temperature or vibration damping at the first location than the modeled, first air-cooled component.

[0024] The respective features of the exemplary embodiments of the invention that are described herein may be applied jointly or severally in any combination or subcombination.

BRIEF DESCRIPTION OF DRAWINGS

[0025] The exemplary embodiments are further described in the following detailed description in conjunction with the accompanying drawings, in which:

[0026] FIG. 1 is a fragmentary, side elevational view of a known gas turbine engine; [0027] FIG. 2 is a fragmentary, axial cross-sectional view through a known, can-type combustion chamber;

[0028] FIG. 3 is a perspective view of a known air-cooled panel of the type used to construct air-cooled component of the engine of FIGs. 1 and 2;

[0029] FIG. 4 is a cross-sectional view of the air-cooled panel of FIG. 3;

[0030] FIG. 5 is a fragmentary, axial cross-sectional view through an embodiment of a can-type combustion chamber, which is constructed in accordance an embodiment described herein, which has a monolithic, three-dimensional lattice structure of selectively oriented metallic webs, and asymmetrical- and serpentine-shaped, locally- varying air passages formed in the interstices between the webs, for locally varying compressed air flow within the combustion chamber;

[0031] FIG. 6 is a perspective view of another embodiment of a premixer, which has a monolithic, three-dimensional lattice structure of selectively oriented metallic webs, and asymmetrical- and serpentine-shaped passages;

[0032] FIG. 7 is a schematic, fragmentary cross-sectional view of a premixer that is constructed in accordance with another embodiment of a three-dimensional lattice structure of selectively oriented metallic webs, and asymmetrical- and serpentine- shaped passages;

[0033] FIG. 8 is a schematic, fragmentary, perspective view of an air-cooled panel, constructed in accordance an embodiment described herein, which has a monolithic, three-dimensional lattice structure of selectively oriented metallic webs, and asymmetrical- and serpentine-shaped, locally-varying air passages formed in the interstices between the webs, for locally varying one or more of cooling air flow into, and/or within, and/or out of the panel, and/or lattice density, and/or air-flow porosity, for locally varying one or more of local temperature, vibration damping and/or structural properties of the panel;

[0034] FIG. 9 is a schematic, fragmentary cross-sectional view of an air-cooled panel premixer that is constructed in accordance with another embodiment that is described herein, shown in a flat state;

[0035] FIG. 10 is a schematic, fragmentary cross-sectional view of an air-cooled panel premixer that is constructed in accordance with another embodiment that is described herein, which has been rolled into a curved profile, such as for use in fabrication of a cylindrical combustion chamber or exhaust transition;

[0036] FIG. 11 is a schematic, cross-sectional, plan view of an array of internal lattice webs, cooling-air passages, and holes in another embodiment of a cooling-air panel that is described herein;

[0037] FIG. 12 is a schematic plan view of an array of lattice webs, cooling-air passages, and asymmetrically-shaped cooling-air holes, on an outer surface of another embodiment of an cooling-air panel that is described herein;

[0038] FIGs. 13-16 are perspective, schematic views showing sequential construction of different embodiments of cooling-air panels by additive manufacture, wherein three-dimensional lattice webs are applied to a flat sheet substrate;

[0039] FIG. 17 is a schematic, cross-sectional view of another embodiment of a composite cooling-air panel, which is constructed with a pair of interlocking first and second sheets, each defining lattice webs and passages; and

[0040] FIG. 18 is a flowchart showing an embodiment of a method for normalizing cooling-air flow within an air-cooled component for an engine, by designing and manufacturing an air-cooled component, such as an air-cooling panel, in accordance with embodiments described herein, which has a monolithic, three-dimensional lattice structure of locally varying, selectively oriented webs, and asymmetrical- and serpentine-shaped passages between the webs that define locally varying air-cooling passages.

[0041] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. The figures are not drawn to scale.

DESCRIPTION OF EMBODIMENTS

[0042] Exemplary embodiments of the invention are utilized in air-cooled components for combustion turbine engines, including air-cooled panels, which are incorporated within such air-cooled components. The air-cooled component has a monolithic, three-dimensional lattice structure of selectively oriented metallic webs with locally varying lattice density, and asymmetrical- and serpentine-shaped passages formed between the metallic webs for receiving compressed cooling air. The component lattice structure locally varies one or more of lattice density, or cooling airflow rate, or flow volume or flow direction throughout its three- dimensional volume, for locally varying heat transfer and/or vibration damping properties of the component. The lattice structure is incorporated into any one or more of a combustor, or an exhaust, or a transition, or a nozzle, or a liner heatshield, or a tile, or a seal, or an impingement plate, or a liner, or a chute, or a damper, or a ring, or a baffle, or a vane, or a vane ring, or an air-cooled panel of a combustion turbine engine.

[0043] Past emission and vibration challenges associated with fuel, air and combustion flows within combustion turbine engines are described, and inventive solutions described in the aforementioned International Application serial number PCT/US 17/ 16420, entitled "COMBUSTOR WITH THREE-DIMENSIONAL LATTICE PREMIXER", and International Application serial number PCT/US 17/16391, entitled "METHOD FOR NORMALIZING FUEL- AIR MIXTURE WITHIN A COMBUSTOR" , both filed on February 3, 2017. The premixer embodiments of the invention described in that application locally vary structure of one or more of air ducts, fuel delivery passages, fuel and air mixing ducts, and/or fuel and air discharge ducts, in order to normalize fuel-air ratio at any location about the premixer' s three-dimensional volume, or in the combustion chamber, during steady-state operating conditions, and/or in order to stabilize fluctuations in compressed air supply to the premixer, and/or in order to stabilize fluctuations in combustion gas backpressure upstream into the premixer, and/or in order to stabilize combustion mass flow within the combustor. The described premixer includes a monolithic, three-dimensional lattice structure of selectively oriented, asymmetrical- and serpentine-shaped metallic webs.

[0044] FIG. 5 shows an exemplary embodiment of a three-stage, can-type combustor 100 for a combustion turbine engine, which incorporates a fuel-air premixer ("premixer") 150, with a three-dimensional lattice structure. The combustor 100 is substituted for the prior art combustor 38 of the combustion turbine engine 20, shown in FIG. 1 or the combustor 40 of FIG 2. Referring to FIGs. 5 and 6, the combustor 100 is a can-type, three-stage combustor, enveloped by a combustor outer casing 102, which receives compressed air CP from the compressor of the engine section via an air intake 104. An annular air intake plenum 106 is defined between the interior of the combustor outer casing 102 and the premixer 150. The exemplary embodiment premixer 150 is a monolithic, three-dimensional lattice structure of selectively oriented, asymmetrical- and serpentine-shaped metallic webs.

[0045] As shown in greater detail in the embodiment of FIG. 6, the premixer 150 has a generally annular shape, with an outer circumferential surface 152 that is in fluid communication with the air intake plenum 106, an inner circumferential surface 154 that abuts and is in fluid communication with a stepped, annular combustion chamber 120, an upper axial surface 156 that abuts the combustor outer casing 102, and a lower axial surface 158 that is in communication with the air intake 104 and the air intake plenum 106. The metallic web forms a three-dimensional, lattice-like mesh 160 that defines locally apertures and passages 162 of varying profile and dimensions along one or more of its outer circumferential surface 152 (e.g., about the axial length L and about varying angular positions Θ along its outer circumferential surface), its inner circumferential surface 154, and optionally on its upper 156 and lower 158 axial surfaces, of the lattice structure of the premixer 150. The lattice-like mesh 160 defines locally apertures and passages 162, within the interior volume of the premixer 150.

[0046] The locally varying structure of the lattice-like mesh 160 with its integral passages 162 within the volume occupied by the premixer 150 (bounded within the envelope of dimensions L and Θ), form a plurality of locally varying profile, orientation, and dimension air ducts; fuel delivery passages; fuel and air mixing ducts ("FAMDs"), in fluid communication corresponding air ducts and the fuel delivery passages; and fuel and air discharge ducts ("FADDs"), in fluid communication with their corresponding FAMDs.

[0047] FIG. 7 shows another embodiment of a premixer three-dimensional lattice monolithic structure, with localized variations of the webs, apertures, channels and cavity surfaces that form air ducts, FAMDs, and fuel and air discharge ducts. In FIG. 7, fragmentary view of a premixer 170 shows a lattice-like structure of generally vertically oriented webs 172, 174, 176, and generally horizontally oriented webs 178, 180, 182, 184, 186. In this example, the horizontally oriented webs 178, 180, 182, 184, 186 have varying density or pitch Pi, P 2 , P 3 , and thickness Ti, T 2 . Aperture or passage 188 has a constant height Y, while passage 190 has a varying width X. The passage 192 is of generally circular cross section, while the passage 194 has an irregularly shaped cross section.

[0048] Construction of the various ducts and fuel delivery passages of the premixer 150 of FIG. 5 is now described in detail. An air intake plenum 106 is in fluid communication with the interior volume of the premixer 150, through passages 162 formed in the outer circumferential surface 152 and in some embodiments, the lower axial surface 158. The passages 162 formed in outer circumferential surface 152 and/or the a lower axial surface 158 function as air duct passages, which are in turn in fluid communication with respective, separate and isolated primary fuel and air mixing duct ("FAMD") 108 (see exemplary airflow arrows A and B), secondary FAMD 110 (see exemplary airflow arrows C and D), and tertiary FAMD 112 (see exemplary airflow arrows E). In some embodiments, one or more of the FAMDs 108, 110 and 112 has an annular construction, fully circumscribing the combustion chamber 120.

[0049] The primary FAMD 108 is in fluid communication with an annular manifold of a primary fuel delivery system 114. Similarly, the secondary FAMD 110 is in fluid communication with an annular manifold of a secondary fuel delivery system 116, and the tertiary FAMD 112 is in fluid communication with an annular manifold of a tertiary fuel delivery system 118. Within each of the FAMDs 108, 110 and 112, fuel F, supplied by each corresponding fuel delivery system 114, 116, 118 is entrained within the compressed air CP, at a desired fuel-air ratio. The compressed air CP is supplied to the corresponding FAMDs 108, 110 and 112 through the respective corresponding air ducts that are formed within the passages 162, along the paths indicated by the flow arrows A, B, C, D and E. In some embodiments, one or more of the fuel delivery systems 114, 116 or 118 comprise pressurized fuel rails obtained from a pressurized fuel source, which in turn are coupled to fuel injection nozzles, orifices or the like that introduce fuel into its corresponding FAMD. The fuel and air are mixed in each FAMD 108, 110, and 112.

[0050] The fuel and air mixture discharges from the primary FAMD 108 through primary fuel and air discharge duct ("FADD") 130 and primary FADD outlet 131. In some embodiments, a flow directing swirler is incorporated on the downstream end of the FAMD 108, or any of the other FAMDs 110 or 112, in order to direct the fuel-air mixture within the corresponding primary fuel and air discharge duct. The fuel and air mixture discharges from secondary FAMD 110 via secondary fuel and air discharge duct 132, and from the tertiary FAMD 112 via tertiary fuel and air discharge duct 134. In some embodiments, one or more of the fuel and air discharge ducts 130, 132, or 134 has an annular construction, fully circumscribing the combustion chamber 120. The respective fuel and air discharge ducts 130, 132, 134 are in fluid communication with, and discharge their respective fuel and air mixtures FA1, FA2 and FA3 into the combustion chamber 120. In some embodiments, discharge location of the FADDs 130, 132, 134 varies locally about the combustion chamber 120, for example to resist local variations in combustion backpressure BP, or backpressure pulsation ΔΒΡ.

[0051] The combustion chamber 120 has an upper axial end that is defined by an upstream wall 121. The upstream wall 121 defines an upstream axial limit of a primary combustion zone 122. A primary annular wall 123 defines a circumferential axial limit of the primary combustion zone 122. The fuel and air mixture supplied by the primary FAMDs 108 enters the primary combustion zone 122 via the corresponding, coupled array of primary fuel and air discharge ducts 130 (arrow FA1). The combustion chamber 120 has a secondary combustion zone 124, circumferentially defined by a secondary annular wall 125, downstream of the primary combustion zone 122. The fuel and air mixture supplied by the secondary FAMDs 110 enters the secondary combustion zone 124 via the corresponding, coupled array of secondary fuel and air discharge ducts 132 (arrow FA2). A tertiary combustion zone 126 is circumferentially defined by a tertiary annular wall 127, downstream of the secondary combustion zone 124. The fuel and air mixture supplied by the tertiary FAMDs 112 enters the tertiary combustion zone 126 via the tertiary fuel and air discharge ducts 134 (arrow FA3).

[0052] In the embodiment of FIG. 5, the combustion chamber walls 121, 123, 125, and 127 are integrally formed as part of the inner circumferential surface 154 of the premixer 150. In other embodiments, the combustion chamber walls are formed in a separate sleeve or interlocking sleeves, which are subsequently circumscribed by the premixer inner circumferential surface 154. In some embodiments, the sleeve structure comprises a rolled, air-cooled panel that is constructed in accordance with embodiments of the present invention, with air-cooling passages formed between webs within a three-dimensional lattice structure. In other embodiments, the three- dimensional lattice structure is formed within the chamber wall during its fabrication, such as by additive manufacture. [0053] FIG. 8 shows an air-cooled panel 200, which is incorporated into structure of air-cooled components, for a combustion turbine engine, such as the engine 20 of FIGs. 1, 2, and 4-7. Exemplary air-cooled components suitable for incorporation of the air-cooled panel structure 200 include, without limitation, one or more of the combustors 20 or 100, the exhaust 32, the transition 39, or nozzles of the fuel delivery systems 114, 116, 118, or a liner heat shield, or a liner, or a ring 25B, 29B, or a baffle, or a vane 27A, or a vane ring 27B the combustion turbine engine 20.

[0054] The air-cooled panel 200 includes a first planar, metallic sheet 202, having an outer side 204, and an opposed inner side 206. The panel 200 includes a monolithic, three-dimensional lattice structure 210 of selectively oriented metallic webs, such as the truss-like array of rods 212, 214, 216, and asymmetrical- and serpentine-shaped passages 220, 222, 224, formed between the metallic webs, for receiving compressed cooling air. The lattice 210 has a first face 230 bonded to the inner side 206 of the first planar, metallic sheet 202, and a second face 232 opposite the first face. While the embodiment of the 3-D lattice, metallic web 210 comprises the rods 212, 214, 216, the web filaments are of any desired shape, profile, orientation, and metallic density, as was previously described in connection with the respective 3-D lattice, premixer embodiments 150 and 170 of FIGs. 5-7. In general, the 3-D lattice structure 210 has web density and porosity in the interstices between the web filaments, such as the rods 212, 214, 216. As with the premixer 150, locally varying density and porosity of the 3-D lattice 210 enables local modification of cooling airflow rate, or flow volume or flow direction in any one or more of the X, Y and Z-axes directions, for locally varying heat transfer or vibration damping properties within the volume of the panel 200.

[0055] The embodiment of the air-cooled panel 200 has a second planar, metallic sheet 240, with an outer side 242, and an opposed inner side 244 that is coupled to the second face 232 of the lattice structure 210. A second, optional, 3-D lattice 250 of metallic webs 252, 254, 256, 258 project outwardly from the outer side 242 of the second planar, metallic sheet 240, in a locally varying array of surface features, for modifying one or more of external, second lattice density, or cooling air flow rate, or flow volume or flow direction along the outer side 242 of the panel 200, for locally varying heat transfer or vibration damping properties of the panel. Typically the surface feature structures of the second lattice 250 are applied to an impingement surface of an air-cooled component, where it contacts cooling-air flow. In some embodiments, a 3-D lattice of surface features, such as dimples or effusion cooling hole shields, are applied to a "hot side", outer surface of an air-cooled component that is exposed to combustion gasses, as shown and described herein with respect to FIG. 12.

[0056] The cooling panel 200 has cooling holes 260, 270, 272, 274, for passage of cooling air into or out of any one or more of the first planar, metallic sheet 202 or the second planar, metallic sheet 240. Cooling hole pitch, array, density, porosity, shape, profile, and angular orientation relative to the corresponding outer surface 204 or 242 of the cooling panel 200 is selectively varied in order to achieve desired heat transfer and/or vibration damping properties. For example, if the outer surface 242 of the cooling panel 200 is an impingement surface, in contact with circulating cooling air bled from the compressor section 24 of the turbine engine 20, the cooling holes 270, 272 and 274 comprise impingement cooling holes, for passage of cooling air into the passages 220, 222, 224 of the lattice structure 210, in the general direction of the Z axis. In such an application, the cooling holes 260 comprise effusion cooling holes, for passage of cooling air out of the lattice structure 210, in the general direction of the Z axis, and along the outer surface 204 of the cooling panel 200 (axes X and Y).

[0057] In FIGs. 9 and 10, the respective air-cooled panels 300 and 400 are bendable along a radius of curvature, such as the radius R of FIG. 10, without generating cracks in the panels. The air-cooled panel 300 includes a first planar, metallic sheet 302, having an outer side 304, and an opposed inner side 306. The panel 300 includes a monolithic, three-dimensional lattice structure 310 of selectively oriented metallic webs, such as the truss-like array of rods 312, 314, 316, 317, and 318; and asymmetrical- and serpentine-shaped passages 320, 322, 324, formed between the metallic webs, for receiving compressed cooling air. The lattice 310 has a first face 330 bonded to the inner side 306 of the first planar, metallic sheet 302, and a second face 332 opposite the first face. While the embodiment of the 3-D lattice, metallic web 310 comprises the rods 312, 314, 316, 317, and 318, the web filaments are of any desired shape, profile, orientation, and metallic density, as was previously described in connection with the respective 3-D lattice 210 of FIG. 8, for locally varying heat transfer or vibration damping properties of the panel 300. The embodiment of the air- cooled panel 300 has a second planar, metallic sheet 340, with an outer side 342, and an opposed inner side 344 that is coupled to the second face 332 of the lattice structure 310. A second, optional, 3-D lattice 350 of metallic webs 352, 354, 356, 358 project outwardly from the outer side 342 of the second planar, metallic sheet 340, in a locally varying array of surface features, for modifying one or more of external, second lattice density, or cooling air flow rate, or flow volume or flow direction along the outer side 242 of the panel 200, for locally varying heat transfer or vibration damping properties of the panel. The cooling panel 300 has cooling holes 360, 370, 372, for passage of cooling air into or out of any one or more of the first planar, metallic sheet 302 or the second planar, metallic sheet 340.

[0058] In FIG. 10, the cooling panel 400 is shown as rolled into a curved air-cooled sleeve component having the radius of curvature R, wherein cooling air impinges on the inner radius surface 442, while the outer radius surface 404 is exposed to hotter temperatures. In some embodiments, the cooling component is constructed initially in the curved shape, or any other desired three-dimensional shape. The air-cooled panel 400 includes a first planar, metallic sheet 402, having an outer side 404, and an opposed inner side 406. The panel 400 includes a monolithic, three-dimensional lattice structure 410 of selectively oriented metallic webs, such as the truss-like array of rods 412, 414, 416, 417, and 418; and asymmetrical- and serpentine-shaped passages 420, 422, 424, formed between the metallic webs, for receiving compressed cooling air. The lattice 410 has a first face 430 bonded to the inner side 406 of the first planar, metallic sheet 402, and a second face 432 opposite the first face. While the embodiment of the 3-D lattice, metallic web 410 comprises the rods 412, 414, 416, 417, and 418, the web filaments are of any desired shape, profile, orientation, and metallic density, as was previously described in connection with the respective 3- D lattice 210 of FIG. 8, for locally varying heat transfer or vibration damping properties of the panel 300. The embodiment of the air-cooled panel 400 has a second planar, metallic sheet 440, with an outer side 442, and an opposed inner side 444 that is coupled to the second face 432 of the lattice structure 410. A second, optional, 3-D lattice 450 of metallic webs 452, 454, 456, 458 project outwardly from the outer side 442 of the second planar, metallic sheet 440, in a locally varying array of surface features, for modifying one or more of external, second lattice density, or cooling air flow rate, or flow volume or flow direction along the outer side 442 of the panel 400, for locally varying heat transfer or vibration damping properties of the panel. The cooling panel 400 has cooling holes 460, 462, 470, 472, for passage of cooling air into or out of any one or more of the first planar, metallic sheet 402 or the second planar, metallic sheet 440.

[0059] FIGs. 11 and 12 show schematically, respective local variations in 3-D lattice density and porosity in cooling panels 500 and 600, as was done with the lattice-like premixers of FIGs. 4-7. In both FIGs. 11 and 12, lattice webs are shown schematically as the letter X, in varying web thickness, pitch density and clustering. Spaces or interstices between the X characters are cooling-air passages. Cooling holes of various shapes, pitch, cross section, for passage of cooling air in or out of the panel internal web structure are also shown schematically. More particularly, FIG. 11 is an internal, planar cross section above the top surface 506 of the planar sheet 502, with the outer surface 504 exposed to cooling airflow or combustion gasses, through the lattice structure 510 of cooling panel 500. Topology of the clusters of webs 510, 512, 514 516, 518, 520, 522, 524, 526, 528, 530 and 532 define corresponding cooling passages 534, 536, 538, 540, 542, 544, 546, 550. An array of cooling holes 554, and cooling holes 556, 558 560 facilitate passage of cooling air between the lattice 510 and the outer surface 504 of the cooling panel 500. FIG. 12 shows cooling panel 600, whose planar panel 602 is integrated with the monolithic lattice structure 610. The outer surface 606 of the cooling panel 600 comprises an exposed surface of the lattice 610, with spaces or interstices 612 between web filaments 613 defining porous passages for communication of cooling air between the outer surface and internal passages 615 within the lattice. Thus, in this embodiment the cooling panel 600 facilitates localized variance in porosity and density of the 3-D lattice 610, in all directions X, Y and Z. Profiles, dimensions, angular orientation, pitch, density of the cooling holes 616, 618, 619, 620 are selectively varied to achieve desired cooling-air flow properties, with resultant heat transfer and/or vibration damping, as was previously described with respect to the cooling panel 200 of FIG. 8. Similar concepts of localized airflow control were addressed with respect to the 3-D lattice- type premixer embodiments of FIGs. 5-7. Additional, second external lattice surface features, namely the dimples 622 and 624 are formed on the outer surface 606 of the 3-D lattice 610, for additional heat transfer control.

[0060] FIGs. 13-16 illustrate methods for fabricating air-cooled components for turbine engines, which incorporate, respectively, monolithic, three-dimensional lattice structures of selectively oriented metallic webs with locally varying lattice density, and asymmetrical- and serpentine-shaped passages formed between the metallic webs for receiving compressed cooling air. In FIG. 13, construction of an exemplary air- cooled panel 700 is initiated by placing, and optionally securing on a work surface 701, such as workpiece welding surface of an additive-manufacture, laser welder, a flat, first planar sheet 702, having an outer surface 704, and an inner surface 706. The first planar sheet 702 has optional array of pre-formed cooling holes 760. In FIG. 14, a three-dimensional lattice structure 710 is formed on the inner surface 706 of the first planar sheet 702, by building up a web of filaments 712, 713, 714, 715, 716, 718, 719, such as by an additive manufacture process. Interstices or spaces between those web filaments form asymmetrical- and serpentine-shaped passages 720, 722, 724. In the embodiment of FIG. 15, a second planar sheet 740, having an outer surface 742 and an inner surface 744, is applied, by additive manufacture, on top of the web filaments 711, so that the web filaments and the second planar sheet have a monolithic structure. The cooling panel 700 forms cooling air internal passages 725 and 726 within the panel, between the first 702 and second 740 planar sheets, with the contours and topology of the passages established by the lattice configuration of the monolithic web filaments 711. An optional, second 3-D lattice array 750 of web filaments 752 and 754 is applied over the outer surface 742. One or more optional cooling holes 770 are formed during application of the second planar sheet 740, of any desired shape, profile, dimensions, and/or angular orientation relative to the outer surface 742.

[0061] In the embodiment of FIG. 16, the cooling panel 800, the first planar sheet 802 includes additively applied web filaments 812, 814 projecting from its inner surface 806. A separate planar sheet 840 is bonded to the upwardly projecting ends 813 and 815 of the respective web filaments 812 and 814, such as by diffusion brazing. Optionally, external 3-D lattices 850 and 880 are applied, by additive manufacture buildup of the respective web filament sets 852, 854, 856 and 882, 884, on the respective outer surfaces 804 and 842 of the cooling panel 800. Cooling hole 860 is formed through the first planar sheet 802 (with angular orientation γ relative to its inner surface 806) prior to or after fabrication of the cooling panel 800. Similarly, fan-shaped cooling hole 870 is formed through the second planar sheet 840.

[0062] The cooling panel 900 embodiment, shown schematically in FIG. 17, is formed by mechanical interlocking of first planar sheet 902 and second planar sheet 940 into a composite structure. The first planar sheet 902 has an outer surface 904, an inner surface 906, and a plurality of through-holes 908. A plurality of monolithic web filaments 912 project outwardly from the inner surface 906 of the first planar sheet 902. In some embodiments, the monolithic web filaments 912 are formed by removing material from the first planar sheet 902. In other embodiments, the monolithic web filaments are integrally formed with the first planar sheet 902, via casting or additive manufacture fabrication. Mating, second planar sheet 940 has an outer surface 944, an inner surface 946, and a plurality of through-holes 948. A plurality of monolithic web filaments 914 project outwardly from the inner surface 946. The respective first and second planar panels 902, 940 are interlocked by insertion of mating, corresponding pins 912 into the through holes 948, and by insertion of mating, corresponding pins 914 into the through holes 908. Thereafter, the mating, interlocking relationship of the pins 912, 914 and through-holes 908, 948 is maintained by application of braze or weld beads 950 along the pin and through- hole interfaces.

[0063] As noted, at least with respect to the air-cooled component embodiments 500 and 600 of FIGs. 11 and 12, the 3-D lattice structure within the component modifies locally one or more of lattice density, or lattice porosity, or cooling air flow rate, or flow volume or flow direction throughout the three-dimensional volume of the component, as was done for localized flow control modification within the premixer lattice structures 150 of FIGs. 5 and 6 and/or 170 of FIG. 7. In such air-cooled component embodiments, the locally varying structure within the component locally varies heat transfer or vibration damping properties of the component. Local variances within the component structure better enables achievement of more uniform temperature distribution and/or vibration damping throughout the entire component; for example to maintain temperature below an operational specification for the engine, in order to avoid a "hot spot". Local variation throughout the component structure also increases cooling air allocation efficiency, as no more than a necessary portion of the cooling-air mass flow is utilized within the component. The method is also useful for fabricating an air-cooled panel, such as the panel 200 of FIG. 8.

[0064] Methods for determining profiles and orientations of the various webs, passages between the web interstices, cooling air-flow channels, cooling holes, and heat-transfer surface features throughout the three-dimensional lattice structure, or on exterior surfaces of an air-cooled component ("ACC"), is now described. With reference to FIGs. 1, 5, 8, and 18, this exemplary method is applied to local modifications of the exemplary embodiment of the ACC cooling panel 200, which is used to fabricate a portion of the combustion chamber 120 of the combustor 100, within the engine 20. In the exemplary method 1000 of FIG. 18, at modeling step 1002, structure of the engine 20, including its ACC, air-cooled panel 200 structure within the combustion chamber 120, as well as desired intake air CP from the compressor section, localized mass flow of cooling-air bleed from the compressor section to the air-cooled panel 200, fuel F, fuel and air mixture FA in its premixers and combustion gas flow dynamics within its combustion chamber(s) 120, including combustion backpressure BP dynamics within the combustion chamber(s) 120 and upstream into the 3-D lattice premixer 150, are modeled, in a computer work station, running commercially available structural and fluid dynamics software.

[0065] In step 1004, operation of the modeled combustor 100, including the three- dimensional, lattice-like premixer 150, and the ACC, cooling panel 200 within the combustion chamber 120, are simulated in computer workstation running commercially available computational fluid dynamics ("CFD") simulation software. During the simulated operation, intake air CP, cooling air, fuel F, fuel and air mixture FA in the premixer 150, combustion gas flow dynamics within the combustion chamber 120 (including combustion backpressure BP dynamics within the combustion chamber and upstream into the premixer), as well as localized temperatures and/or vibration characteristics about the ACC, air-cooled panel 200, are evaluated. Empirical, operational knowledge about such flow dynamics, as well as the ACC, panel 200 temperature distribution and/or vibration characteristics, based on past physical observation and simulations are utilized to evaluate the CFD simulations. Local deviations from desired temperatures or vibration characteristics at one or more locations about the ACC, panel 200, and the sources of such deviations are identified and evaluated during the operational simulations.

[0066] In step 1006, the ACC panel 200 structure, including its respective first 210 and second 250, three-dimensional lattice structures, and/or cooling hole 260, 270, 272, 274, as well as structure of any other components in the combustor 100, are revised and altered, in order to achieve desired temperature distribution and/or vibration damping within the panel 200 and/or the other portions of the engine 20. For example, localized variations desired temperature distribution or vibration within the combustion chamber 120, at different circumferential angular or axial positions, are compensated by altering locally one or more of lattice(s) 210 or 250 density, or cooling air flow rate, or flow volume or flow direction throughout the three- dimensional volume thereof, and/or one or more of angular orientation, pitch, cross- section and shape of the cooling holes 260, 270, 272 274. Localized cooling-air flow into any portion of other air-cooled components is similarly evaluated and compensated as necessary.

[0067] Upon achievement of satisfactory temperature and/or vibration damping results at one or more locations within the engine 20, after revision of the localized structure of the ACC, panel 200, its revised structural model is stored in step 1008. If desired, the modeling and evaluation step 1006, and storage of revised models of step 1008 are sequentially repeated for other air-cooled components within the engine 20.

[0068] In step 1010 of FIG. 18, the stored, revised structural model of the ACC, panel 200 of step 1008 is used to construct the combustion chamber 120 of FIG. 5, and any other desired air-cooled components of the engine 20. In this described embodiment, manufacture focus is on the combustion chamber, with its cooling panel 200. The exemplary cooling panel 200 is constructed as shown in FIGs. 13-16, then rolled into one or more of the annular walls 123, 125 127 of the combustion chamber 120.

[0069] Metal alloys used to form the cooling panel 200, as well as other air-cooled components within the engine, are typically nickel/cobalt/chromium-based, so-called superalloys. The locally varying web and passage profiles of the various embodiments of the monolithic, three-dimensional lattice structures 160, 210, 250, 310, 350, 410, 450, 510, 610, 710, or the respective monolithic premixers or air- cooled components of FIGs. 5-12 are not readily accomplished by traditional metal component fabrication and welding methods. While known, unistructural welded metal premixers 47 of FIG. 2 and cooling panels 60 of FIGs. 3 and 4, have been formed in the past, by traditional metal cutting methods and welding, including electro-discharge machining ("EDM"), those methods cannot readily fabricate complex, internal webs and passages in the spaces between the webs, within a monolithic, 3-D lattice's internal volume space. Traditional metal casting methods, using molds with mold cavities and mold cavity inserts, also cannot readily fabricate complex, internal webs and passages within a 3-D lattice's internal volume space.

[0070] In performing step 1010 of FIG. 18 of the method embodiments, monolithic, three-dimensional lattice structures 160, 210, 250, 310, 350, 410, 450, 510, 610, 710, 750, 850 and 880, of the respective monolithic premixers or air-cooled components of FIGs. 5-17 are fabricated, using additive manufacture methods. In some embodiments, at least the 3-D lattice structure of the premixer or air-cooled component is directly constructed by additive manufacture. Exemplary additive- manufacture methods include by way of non-limiting example: • Selective laser melting by powder bed fusion laser;

• Selective laser melting by powder bed electron beam melting;

• Atomic diffusion additive manufacturing (e.g., by 3D printing and metal injection molding); and

• Direct energy deposition (e.g., blown powder).

[0071] In other embodiments, the monolithic, three-dimensional lattice structures 150, 170, 210, 250, 310, 350, 410, 450, 510, 610, 710, 750, 850 and 880, of the respective monolithic premixers or air-cooled components of FIGs. 5-17 are fabricated by a sacrificial-pattern, mold-casting process. A pattern mold, which replicates the structure of the desired, monolithic, three-dimensional lattice structure of selectively oriented metallic webs, and asymmetrical- and serpentine-shaped and passages between the webs, is formed by an additive manufacture process. The pattern mold is encased in a metal casting mold. The formed mold is filled with molten metal, which displaces the sacrificial mold pattern. After the molten metal hardens, the surrounding mold is removed. The completed cast-metal premixer or cooling panel replicates the desired, monolithic, three-dimensional lattice structure of selectively oriented, metallic webs and passages.

[0072] Although various embodiments that incorporate the invention have been shown and described in detail herein, others can readily devise many other varied embodiments that still incorporate the claimed invention. The invention is not limited in its application to the exemplary embodiment details of construction and the arrangement of components set fort in the description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. The phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of "including," "comprising," or "having" and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms "mounted", "connected", "supported", and "coupled" and variations thereof are used broadly and encompass direct and indirect mountings, connections, supports, and couplings. Further,

-28- "connected" and "coupled" are not restricted to direct physical or mechanical connections or couplings.