Selective steam distribution to steam cooled zones in a turbine engine

A control method is provided during which a turbine engine is operated. The turbine engine includes a plurality of steam cooled zones along a flowpath within the turbine engine. Steam is distributed between the steam cooled zones based on a first distribution while the turbine engine is operating in a first mode. The steam is distributed between the steam cooled zones based on a second distribution while the turbine engine is operating in a second mode. The second distribution is different than the first distribution.

BACKGROUND OF THE DISCLOSURE

1. Technical Field

This disclosure relates generally to a turbine engine and, more particularly, to utilizing steam during operation of the turbine engine.

2. Background Information

As government emissions standards tighten, interest in alternative fuels for gas turbine engines continues to grow. There is interest, for example, in fueling a gas turbine engine with hydrogen (H2) fuel rather than a traditional hydrocarbon fuel such as kerosine to reduce greenhouse emissions. Combustion products produced by combusting hydrogen (H2) fuel include water vapor. Various systems and methods are known in the art for recovering the water vapor. Various system and methods are also known in the art for producing and utilizing steam from the recovered water vapor. While these known systems and methods have various advantages, there is still room in the art for improvement.

SUMMARY OF THE DISCLOSURE

According to an aspect of the present disclosure, a control method is provided during which a turbine engine is operated. The turbine engine includes a plurality of steam cooled zones along a flowpath within the turbine engine. Steam is distributed between the steam cooled zones based on a first distribution while the turbine engine is operating in a first mode. The steam is distributed between the steam cooled zones based on a second distribution while the turbine engine is operating in a second mode. The second distribution is different than the first distribution.

According to another aspect of the present disclosure, another control method is provided during which fuel is injected into a combustion chamber of a combustor of a turbine engine. The fuel is injected into the combustion chamber at a first flowrate during a first power setting. The fuel is injected into the combustion chamber at a second flowrate during a second power setting. The second flowrate is different than the first flowrate. The fuel is combusted within the combustion chamber. Steam is distributed between a plurality of steam cooled zones which include a first zone and a second zone. The steam is distributed according to a first ratio between the first zone and the second zone during the first power setting. The steam is distributed according to a second ratio between the first zone and the second zone during the second power setting. The second ratio is different than the first ratio.

According to still another aspect of the present disclosure, an assembly is provided for a turbine engine. This assembly includes a combustor, a fuel system and a cooling system. The combustor includes a combustion chamber. The fuel system includes a fuel injector assembly arranged with the combustor. The fuel system is configured to inject fuel into the combustion chamber through the fuel injector assembly at a first flowrate during a first power setting and at a second flowrate during a second power setting. The first flowrate is different than the second flowrate. The cooling system includes a plurality of steam cooled zones arranged about the combustion chamber. The cooling system is configured to: distribute steam between the steam cooled zones based on a first distribution during the first power setting; and distribute the steam between the steam cooled zones based on a second distribution during the second power setting. The second distribution is different than the first distribution.

A first of the steam cooled zones includes a portion of the combustor.

The assembly may also include a structure arranged with the combustor. A first of the steam cooled zones may include at least a portion of the structure.

The steam cooled zones may include a first zone and a second zone. The first distribution may provide a first ratio of the steam distributed between the first zone and the second zone. The second distribution may provide a second ratio of the steam distributed between the first zone and the second zone. The second ratio may be different than the first ratio.

The steam cooled zones may also include a third zone. The first ratio may be a ratio of the steam distributed between the first zone, the second zone and the third zone. The second ratio may be a ratio of the steam distributed between the first zone, the second zone and the third zone.

The steam cooled zones may include a first zone and a second zone. The first distribution may provide the steam to the first zone and not to the second zone. In addition or alternatively, the second distribution may provide the steam to the second zone and not to the first zone.

The steam cooled zones may include a first zone. The first distribution may provide a first flowrate of the steam to the first zone. The second distribution may provide a second flowrate of the steam to the first zone. The second flowrate of the steam to the first zone may be different than the first flowrate of the steam to the first zone.

The steam cooled zones may also include a second zone. The first distribution may provide a first flowrate of the steam to the second zone. The second distribution may provide a second flowrate of the steam to the second zone. The second flowrate of the steam to the second zone may be different than the first flowrate of the steam to the second zone.

The second flowrate of the steam to the first zone may be greater than the first flowrate of the steam to the first zone. The second flowrate of the steam to the second zone may be greater than the first flowrate of the steam to the second zone.

The second flowrate of the steam to the first zone may be greater than the first flowrate of the steam to the first zone. The second flowrate of the steam to the second zone may be less than the first flowrate of the steam to the second zone.

The steam cooled zones may also include a second zone. The first distribution may provide a first flowrate of the steam to the second zone. The second distribution may provide a second flowrate of the steam to the second zone. The second flowrate of the steam to the second zone may be equal to the first flowrate of the steam to the second zone.

A first of the steam cooled zones may include at least a portion of a fuel injector assembly.

A first of the steam cooled zones may include at least a portion of a combustor bulkhead.

A first of the steam cooled zones may include at least a portion of a combustor wall.

A first of the steam cooled zones may include at least a portion of a stator vane array downstream of a combustion chamber along the flowpath.

A first of the steam cooled zones may include a first portion of a structure of the turbine engine along the flowpath. A second of the steam cooled zones may include a second portion of the structure of the turbine engine along the flowpath.

The operating of the turbine engine may include injecting fuel into a combustor of the turbine engine at a first flowrate during the first mode. The operating of the turbine engine may include injecting fuel into the combustor at a second flowrate during the second mode. The second flowrate may be different than the first flowrate.

A first of the steam cooled zones may be symmetrically cooled with the steam about a centerline during the operating of the turbine engine.

DETAILED DESCRIPTION

FIG.1is a side sectional illustration of a gas turbine engine20for an aircraft propulsion system. This turbine engine20extends axially along an axial centerline22between a forward, upstream end24and an aft, downstream end26. The turbine engine20includes a fan section28, a compressor section29, a combustor section30and a turbine section31. The compressor section29ofFIG.1includes a low pressure compressor (LPC) section29A and a high pressure compressor (HPC) section29B. The turbine section31ofFIG.1includes a high pressure turbine (HPT) section31A and a low pressure turbine (LPT) section31B.

The engine sections28-31B ofFIG.1are arranged sequentially along the axial centerline22within an engine housing32. This engine housing32includes an inner case34(e.g., a core case) and an outer case36(e.g., a fan case). The inner case34may house one or more of the engine sections29A-31B; e.g., a core of the turbine engine20. The outer case36may house at least the fan section28.

Each of the engine sections28,29A,29B,31A and31B includes a respective bladed rotor38-42. Each of these bladed rotors38-42includes a plurality of rotor blades arranged circumferentially around and connected to one or more respective rotor disks and/or hubs. The rotor blades, for example, may be formed integral with or mechanically fastened, welded, brazed, adhered and/or otherwise attached to the respective rotor disk(s) and/or the respective hub(s).

The fan rotor38is connected to a geartrain44, for example, through a fan shaft46. The geartrain44and the LPC rotor39are connected to and driven by the LPT rotor42through a low speed shaft47. The HPC rotor40is connected to and driven by the HPT rotor41through a high speed shaft48. The engine shafts46-48are rotatably supported by a plurality of bearings; e.g., rolling element and/or thrust bearings. Each of these bearings is connected to the engine housing32by at least one stationary structure such as, for example, an annular support strut.

During engine operation, air enters the turbine engine20through an airflow inlet50into the turbine engine20. This air is directed through the fan section28and into a core flowpath52and a bypass flowpath54. The core flowpath52extends sequentially through the engine sections29A-31B (e.g., the engine core) from an inlet56into the core flowpath52to an exhaust58from the core flowpath52. The air within the core flowpath52may be referred to as “core air”. The bypass flowpath54extends through a bypass duct, and bypasses the engine core. The air within the bypass flowpath54may be referred to as “bypass air”.

The core air is compressed by the LPC rotor39and the HPC rotor40and directed into a (e.g., annular) combustion chamber60of a (e.g., annular) combustor62in the combustor section30. Fuel is injected by one or more fuel injector assemblies64(one visible inFIG.1) into the combustion chamber60and mixed with the compressed core air to provide a fuel-air mixture. This fuel-air mixture is ignited and combustion products thereof flow through and sequentially cause the HPT rotor41and the LPT rotor42to rotate before being directed out of the turbine engine20through the core exhaust58. The rotation of the HPT rotor41and the LPT rotor42respectively drive rotation of the HPC rotor40and the LPC rotor39and, thus, compression of the air received from the core inlet56. The rotation of the LPT rotor42also drives rotation of the fan rotor38, which propels the bypass air through the bypass flowpath54and out of the turbine engine20through an exhaust66from the bypass flowpath54. The propulsion of the bypass air may account for a majority of thrust generated by the turbine engine20.

FIG.2illustrate a portion of the combustor section30along the core flowpath52between the HPC section29B and the HPT section31A. This combustor section30includes the combustor62, a diffuser plenum68and the one or more injector assemblies64(one visible inFIG.2). Briefly, the combustor62is disposed within (e.g., surrounded by) the diffuser plenum68. This diffuser plenum68receives the compressed core air from the HPC section29B for subsequent provision into the combustion chamber60. Each injector assembly64ofFIG.2includes a fuel injector70mated with an air swirler structure72. The fuel injector70injects the fuel into the combustion chamber60. The air swirler structure72directs some of the core air from the diffuser plenum68into the combustion chamber60in a manner that facilitates mixing the core air with the injected fuel. One or more igniters (not shown) ignite the fuel-air mixture within the combustion chamber60. One or more quench apertures74A,74B (generally referred to as “74”) (e.g., dilution holes) in each wall76A,76B (generally referred to as “76”) of the combustor62direct additional core air from the diffuser plenum68into the combustion chamber60to quench (e.g., stoichiometrically lean) the combustion products; e.g., the ignited fuel-air mixture.

The combustor62may be configured as an annular combustor; e.g., an annular floating wall combustor. The combustor62ofFIGS.2and3, for example, includes an annular combustor bulkhead78, the tubular inner combustor wall76A (“inner wall”), and the tubular outer combustor wall76B (“outer wall”). The bulkhead78ofFIG.2extends radially between and to the inner wall76A and the outer wall76B. The bulkhead78may be connected (e.g., mechanically fastened or otherwise attached) to the inner wall76A and/or the outer wall76B. Each combustor wall76projects axially along the axial centerline22out from the bulkhead78towards the HPT section31A. The inner wall76A ofFIG.2, for example, projects axially to and may be connected to an inner platform80A of a downstream stator vane array82(e.g., a turbine inlet nozzle) in the HPT section31A. The outer wall76B ofFIG.2projects axially to and may be connected to an outer platform80B of the downstream stator vane array82. With the arrangement ofFIG.2, the combustion chamber60is formed by and extends radially within the combustor62between and to the inner wall76A and the outer wall76B. The combustion chamber60is formed by and extends axially (in an upstream direction along the core flowpath52) into the combustor62from the stator vane array82to the bulkhead78. The combustion chamber60also extends within the combustor62circumferentially about (e.g., completely around) the axial centerline22, which may configure the combustion chamber60as a full-hoop annulus.

Any one or more or all of the walls76A,76B,78may each be configured as a multi-walled structure; e.g., a hollow, dual-walled structure. For example, referring toFIG.4, each wall76A,76B,78includes a combustor wall shell84, a combustor wall heat shield86(e.g., a liner) and one or more combustor wall cooling cavities88(e.g., impingement cavities) formed by and (e.g., radially and/or axially) between the shell84and the heat shield86. Each cooling cavity88ofFIG.4is fluidly coupled with the diffuser plenum68through one or more cooling apertures90in the shell84; e.g., impingement apertures. Each cooling cavity88ofFIG.4is fluidly coupled with the combustion chamber60through one or more cooling apertures92in the heat shield86; e.g., effusion apertures. Of course, various other multi-walled combustor wall structures are known in the art, and the present disclosure is not limited to any particular ones thereof. Furthermore, it is contemplated any one or more or all of the walls76A,76B and/or78ofFIG.2may each alternatively be configured as a single-walled structure. The shell84ofFIG.4, for example, may be omitted and the heat shield86may form a single walled liner/wall. However, for ease of description, each wall76A,76B,78may each be described below as the hollow, dual-walled structure.

Referring toFIG.2, the stator vane array82includes the inner platform80A, the outer platform80B and a plurality of stator vanes94(one visible inFIG.2); e.g., hollow stator vanes. The stator vanes94are arranged circumferentially about the axial centerline22in an array; e.g., a circular array. Each of these stator vanes94extends radially across the core flowpath52between and to the inner platform80A and the outer platform80B. Each of the stator vanes94may also be connected to the inner platform80A and/or the outer platform80B. The stator vane array82and its stator vanes94are configured to turn and/or otherwise condition the combustion products exiting the combustion chamber60for interaction with a first stage of the HPT rotor41(seeFIG.1).

Referring toFIG.5, the turbine engine20includes a fuel system96for delivering the fuel to the combustor62. This fuel system96includes a fuel source98and the one or more fuel injectors70. The fuel source98ofFIG.5includes a fuel reservoir100and/or a fuel flow regulator102; e.g., a valve and/or a pump. The fuel reservoir100is configured to store the fuel before, during and/or after turbine engine operation. The fuel reservoir100, for example, may be configured as or otherwise include a tank, a cylinder, a pressure vessel, a bladder or any other type of fuel storage container. The fuel flow regulator102is configured to direct and/or meter a flow of the fuel from the fuel reservoir100to one or more or all of the fuel injectors70. The fuel injectors70may be arranged circumferentially about the axial centerline22in an array. Each fuel injector70is configured to direct the fuel received from the fuel source98into the combustion chamber60for combustion.

The fuel delivered by the fuel system96may be a non-hydrocarbon fuel; e.g., a hydrocarbon free fuel. Examples of the non-hydrocarbon fuel include, but are not limited to, hydrogen fuel (e.g., hydrogen (H2) gas) and ammonia fuel (e.g., ammonia (NH3) gas). The turbine engine20ofFIG.1may thereby be configured as a non-hydrocarbon turbine engine; e.g., a hydrocarbon free turbine engine. The present disclosure, however, is not limited to non-hydrocarbon turbine engines. The fuel delivered by the fuel system96, for example, may alternatively be a hydrocarbon fuel such as, but not limited to, kerosene or jet fuel. The turbine engine20ofFIG.1may thereby be configured as a hydrocarbon turbine engine. Alternatively, the fuel system96may be configured as a multi-fuel system operable to deliver, individually or in combination, multiple different fuels (e.g., a non-hydrocarbon fuel and a hydrocarbon fuel, etc.) for combustion within the combustion chamber60. The turbine engine20ofFIG.1may thereby be configured as a multi-fuel turbine engine; e.g., a dual-fuel turbine engine. However, for ease of description, the fuel delivered by the fuel system96may be described below as the non-hydrocarbon fuel; e.g., the hydrogen fuel.

Referring toFIG.2, throughout an engine cycle, turbine engine components (e.g.,76A,76B,78and/or94) along the core flowpath52and/or about the combustion chamber60may be subject to varying thermal loads and stresses. These varying thermal loads and stresses may be exacerbated with the use alternative fuels such as the non-hydrocarbon fuel; e.g., the hydrogen fuel. The thermal loads and stresses are elevated along zones subject to thermal hot spots; e.g., regions with locally elevated temperatures. Locations of these hot spots may change based on an operating mode of the turbine engine20; e.g., a power setting of the turbine engine20. For example, during aircraft cruise where the turbine engine20is at a relatively low power setting, the hot spots may form within/along certain region(s) of core flowpath52and its combustion chamber60. By contrast, during aircraft takeoff where the turbine engine20is at a relatively high power setting, the hot spots may form within/along certain other (and/or overlapping) region(s) of the core flowpath52and its combustion chamber60.

Referring toFIG.6, to mitigate the thermal loads and stresses associated with hot spots, the turbine engine20includes an adaptive cooling system104. This cooling system104is configured to adaptively cool a plurality of zones106A-D (generally referred to as “106”) within the turbine engine20using steam. The steam cooled zones106are arranged along the core flowpath52(seeFIG.2) and/or about the combustion chamber60(seeFIG.2). The zone106A, for example, may include at least a portion or an entirety of the combustor bulkhead78and/or the injector assemblies64. The zone106B may include at least a portion or an entirety of the inner wall76A. The zone106C may include at least a portion or an entirety of the outer wall76B. The zone106D may include at least a portion or an entirety of the stator vane array82; e.g., the stator vanes94. The cooling system104ofFIG.6includes a steam source108, a steam delivery circuit110and the steam cooled zones106.

The steam source108is configured to provide the steam to the steam delivery circuit110during turbine engine operation and, more particularly, during cooling system operation. The steam source108, for example, may be configured as or otherwise include an evaporator112, which may be or otherwise include a fluid-to-fluid heat exchanger and/or an electrical heater. The evaporator112is configured to evaporate water into the steam during the cooling system operation. The water may be received from various sources. The steam source108ofFIG.6, for example, includes a water reservoir114fluidly coupled with and upstream of the evaporator112. This water reservoir114is configured to store the water before, during and/or after turbine engine operation. Examples of the water reservoir114include, but are not limited to, a tank, a cylinder, a pressure vessel, a bladder or any other type of water storage container. Briefly, the water may be supplied to the water reservoir114by recovering water vapor from the combustion products flowing through the core flowpath52(seeFIG.1) and/or from another water source onboard or offboard an aircraft.

The steam delivery circuit110ofFIG.6includes a supply circuit116and a plurality of zone circuits118A-D (generally referred to as “118”), where each of the zone circuits118is associated with a respective one of the steam cooled zones106. The supply circuit116ofFIG.6extends from an outlet from the steam source108to an interface with the zone circuits118such as a manifold. At this interface, the zone circuits118may be fluidly coupled in parallel to and downstream of the supply circuit116. Each of the zone circuits118extends from the interface to a respective outlet from that zone circuit118into a respective one of the steam cooled zones106. The steam delivery circuit110and each zone circuit118are thereby operable to direct the steam provided by the steam source108to the respective steam cooled zone106.

The steam provided to each steam cooled zone106A-D may be independently regulated by a steam flow regulator120A-D (generally referred to as “120”). Each steam flow regulator120is arranged (e.g., fluidly coupled inline) with a respective one of the zone circuits118. Each steam flow regulator120is configured to selectively direct and/or meter a flow of the steam from the steam source108to a respective one of the steam cooled zones106. For example, each steam flow regulator120may be configured as or otherwise include a control valve. This control valve may fully open, may fully close and/or may move to one or more partially open positions. While each steam flow regulator120is illustrated inFIG.6as being part of the respective zone circuit118, that steam flow regulator120may alternatively be arranged at the interface between the supply circuit116and the respective zone circuit118, at the outlet from the respective zone circuit118, or otherwise.

With the foregoing arrangement, steam flow to each steam cooled zone106may be independently regulated from the other steam cooled zones106. This may facilitate tailored cooling of the various steam cooled zones106across the engine cycle. In particular, the steam may be selectively distributed between the steam cooled zones106based on, for example, cooling needs for those specific steam cooled zones106. For example, where one or more of the steam cooled zones106are subject to hot spots, the steam flow regulators120for those respective steam cooled zones106may start directing the steam (or direct additional steam) thereto for additional cooling. By contrast, where one or more of the steam cooled zones106are not subject to hot spots, the steam flow regulators120for those respective steam cooled zones106may not direct any of the steam (or less steam) thereto.

As discussed above, the locations of the hot spots may change based on the operating mode of the turbine engine20; e.g., the power setting of the turbine engine20. For example, during one operating mode, the hot spot(s) within the combustion chamber60may be located at or towards the combustor bulkhead78. The steam delivery circuit110may thereby direct more (or all) of the steam to the zone106A. During another operating mode, the hot spot(s) within the combustion chamber60may be located midway between the combustor bulkhead78and the stator vane array82. The steam delivery circuit110may thereby direct more (or all) of the steam to the zone106B and/or the zone106C. During still another operating mode, the hot spot(s) within the combustion chamber60may be located at or towards the stator vane array82. The steam delivery circuit110may thereby direct more (or all) of the steam to the zone106D. Thus, different operating modes may be associated with different steam distributions. Moreover, a ratio of the steam distributed between some or all of the steam cooled zones106may change depending on the operating mode.

The change in the ratio of the steam distribution between the respective steam cooled zones106may be implemented in various manners. For example, when increasing power, a flowrate of the steam to some or all of the steam cooled zones106may increase. However, the increase in the steam provided to one or more of the steam cooled zones106may be more than one or more of the other steam cooled zones106. In another example, when decreasing power, a flowrate of the steam to some or all of the steam cooled zones106may decrease. However, the decrease in the steam to one or more of the steam cooled zones106may be more than one or more of the other steam cooled zones106. In still another example, when changing power, the steam to one or more of the steam cooled zones106may be turned on (or the flowrate increased) while the steam to one or more of the other steam cooled zones106may be turned off (or the flowrate decreased). Thus, the steam provided to each steam cooled zone106may be specifically tailored to the engine operating mode and/or the engine power setting based on predicted hot spot location(s) for that engine operating mode and/or the engine power setting.

FIG.7is a flow diagram of a method700for controlling operation of a gas turbine engine. For ease of description, the control method700is described with respect to the turbine engine20ofFIG.1, the fuel system96ofFIG.5and the cooling system104ofFIG.6. The control method700of the present disclosure, however, is not limited to such an exemplary arrangement.

In step702, the turbine engine20is operated, for example, as described above. During this engine operation, the fuel is injected into the combustion chamber60at a flowrate corresponding to the operating mode of the turbine engine20; e.g., the power setting of the turbine engine20. For example, where the turbine engine20is operating at idle (e.g., an idle power setting), the fuel flowrate may be relatively low. Where the turbine engine20is operating for aircraft cruise (e.g., a low power setting), the fuel flowrate may be moderate. Where the turbine engine20is operating for aircraft takeoff (e.g., a high power setting), the fuel flowrate may be relatively high. During each of these modes of operation, the hot spots within the combustion chamber60/along the core flowpath52may be located at (e.g., slightly) different locations.

In step704, the steam is distributed between the steam cooled zones106based on the engine operating mode/the engine power setting. For example, where the turbine engine20is operating at idle, the steam delivery circuit110may distribute the steam between the steam cooled zones106according to an idle mode steam distribution. Where the turbine engine20is operating for aircraft cruise, the steam delivery circuit110may distribute the steam between the steam cooled zones106according to a cruise mode steam distribution. Where the turbine engine20is operating for aircraft takeoff, the steam delivery circuit110may distribute the steam between the steam cooled zones106according to a takeoff mode steam distribution. The distributions of steam between the steam cooled zones106during these different engine operating modes/engine power settings may be different as discussed above. Therefore, each respective operating mode/power setting may be associated with a unique ratio of the steam distribution between the steam cooled zones106.

While the different steam cooled zones106received tailored steam cooling, each steam cooled zone106may be symmetrically cooled. For example, each steam cooled zone106may be symmetrically cooled about the axial centerline22.

By tailoring steam cooling based on changing cooling needs of the turbine engine components (e.g.,76A,76B,78,94), the cooling system104of the present disclosure may promote increased hot section durability. The tailored distribution of the steam may reduce or prevent component overheating and potentially obviate need to specialty high temperature materials for the turbine engine components (e.g.,76A,76B,78,94). In addition, introducing steam into the combustion chamber60may reduce flame temperature and thereby reduce nitric oxide (NOx) production.

In some embodiments, referring toFIG.8, the steam may be introduced into the zone106A by injecting the steam into a volume between the combustor bulkhead78and a combustor hood122. This steam may directly cool the combustor bulkhead78by contacting a backside of the combustor bulkhead78and/or flowing across the combustor bulkhead78via its cooling apertures and/or cooling cavities. The steam may also pass through the air swirler structures72and provide cooling within the combustion chamber60. The steam may also or alternatively be injected with the fuel through the fuel injector70.

In some embodiments, the steam may be introduced into the diffuser plenum68adjacent the inner wall76A. This steam may directly cool the inner wall76A by contacting a backside of the inner wall76A and/or flowing across the inner wall76A via its cooling apertures and/or cooling cavities.

In some embodiments, the steam may be introduced into the diffuser plenum68adjacent the outer wall76B. This steam may directly cool the outer wall76B by contacting a backside of the outer wall76B and/or flowing across the outer wall76B via its cooling apertures and/or cooling cavities.

In some embodiments, the steam may be introduced into an internal passage in each stator vane94. The steam may then be effused through cooling apertures (e.g., effusion apertures) in a sidewall of each stator vane94.

In some embodiments, each combustor wall76may be included in a single steam cooled zone106. In other embodiments, referring toFIG.9, each combustor wall76may be associated with multiple steam cooled zones106. One steam cooled zone106B′,106C′, for example, may include an upstream portion of the respective combustor wall76A,76B. Another steam cooled zone106B″,106C″ may include a downstream portion of the respective combustor wall76A,76B. Of course, a similar division may also or alternatively be implemented with other steam cooled structures of the turbine engine20.

The cooling system104may be included in various turbine engines other than the one described above. The cooling system104, for example, may be included in a geared turbine engine where a geartrain connects one or more shafts to one or more rotors in a fan section, a compressor section and/or any other engine section. Alternatively, the cooling system104may be included in a turbine engine configured without a geartrain; e.g., a direct drive turbine engine. The cooling system104may be included in a geared or non-geared turbine engine configured with a single spool, with two spools (e.g., seeFIG.1), or with more than two spools. The turbine engine may be configured as a turbofan engine, a turbojet engine, a turboprop engine, a turboshaft engine, a propfan engine, a pusher fan engine or any other type of turbine engine. The turbine engine may alternatively be configured as an auxiliary power unit (APU) or an industrial gas turbine engine. The present disclosure therefore is not limited to any particular types or configurations of turbine engines.