System and method for reducing emissions with fuel cells

Abstract

A gas turbine engine includes a fuel cell assembly, a fuel source, and a turbine. The fuel cell assembly includes a fuel cell stack and defines operating parameters for the fuel cell assembly. The turbine includes a compressor section, a combustor, and a turbine section arranged in a sequential flow order. The combustor is configured to receive a fuel stream from the fuel source and is further configured to receive output products from the fuel cell stack. A controller is configured to operate including receiving data indicating system operating conditions, determining a set of fuel cell operating conditions to shift system emission outputs into or maintain system emission outputs within emission ranges, and controlling the operating parameters of the fuel cell assembly based on the determined set of fuel cell operating conditions.

Description

Technical Field

[0001] This disclosure relates to systems and methods for controlling emissions from a gas turbine engine, the propulsion system including a fuel cell. Background Technology

[0002] A gas turbine engine generally consists of a turbine and a rotor assembly. Gas turbine engines (such as turbofan engines) can be used for aircraft propulsion. In the case of a turbofan engine, the turbine includes a compressor section, a combustion section, and a turbine section in a sequential flow sequence, and the rotor assembly is configured as a fan assembly.

[0003] During operation, air is compressed in the compressor and mixed with fuel in the combustion section and ignited to generate combustion gases, which flow downwards through the turbine section. The turbine section extracts energy from the combustion gases to rotate the compressor section and fan assembly, thereby powering the gas turbine engine and propelling the aircraft containing this gas turbine engine during flight.

[0004] The combustor power is adjusted to meet fan speed or thrust requirements. The temperature of the combustor in the combustion zone can depend on the combustor power and can be an operational limitation of the gas turbine engine. Therefore, achieving the desired combustor power may cause the combustor temperature to change in a way that increases emissions. If the combustor temperature is too low, carbon monoxide (CO) may increase. And if the combustor temperature is too high, nitrogen oxides (NOx) will increase. x This could increase. Therefore, systems and methods capable of achieving desired burner power while reducing emissions will be welcomed in this field. Attached Figure Description

[0005] The complete and feasible disclosure of this disclosure, including its best mode, is set forth in the specification with reference to the accompanying drawings, for those skilled in the art, wherein:

[0006] Figure 1 This is a cross-sectional view of a gas turbine engine according to an exemplary aspect of this disclosure.

[0007] Figure 2 This is a perspective view of the integrated fuel cell and burner assembly according to this disclosure.

[0008] Figure 3 yes Figure 2 A schematic axial view of an exemplary integrated fuel cell and burner assembly.

[0009] Figure 4 This is a schematic diagram of a fuel cell assembly according to an exemplary aspect of the present disclosure, the fuel cell being incorporated into... Figure 2 An exemplary integrated fuel cell and burner assembly.

[0010] Figure 5 This is a schematic diagram of a gas turbine engine including an integrated fuel cell and burner assembly, according to an exemplary aspect of this disclosure.

[0011] Figure 6 This is a schematic diagram of a vehicle and propulsion system according to an exemplary aspect of this disclosure.

[0012] Figure 7 It is a graph depicting the relationship between carbon monoxide emissions and nitrogen oxide emissions relative to the burner temperature in an exemplary burner according to an exemplary aspect of this disclosure.

[0013] Figure 8 Based on exemplary aspects of this disclosure Figure 5 The flowchart of the controller for the launch vehicle and propulsion system.

[0014] Figure 9 Based on exemplary aspects of this disclosure Figure 8 The table of the controller.

[0015] Figure 10 Based on exemplary aspects of this disclosure Figure 8 The flowchart of the controller.

[0016] Figure 11 This is a flowchart of a method according to an exemplary aspect of this disclosure. Detailed Implementation

[0017] Reference will now be made in detail to the present embodiments of this disclosure, one or more examples of which are illustrated in the accompanying drawings. The detailed description uses numerals and letter reference numerals to denote features in the drawings. Similar or analogous reference numerals in the drawings and description have been used to denote similar or analogous portions of this disclosure.

[0018] The term "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any implementation described herein as "exemplary" is not necessarily to be construed as superior or better than other implementations. Furthermore, unless explicitly stated otherwise, all embodiments described herein should be considered exemplary.

[0019] For the purposes described below, the terms “upper,” “lower,” “right,” “left,” “vertical,” “horizontal,” “top,” “bottom,” “lateral,” “longitudinal,” and their derivatives should be associated with the embodiments in which they are oriented in the accompanying drawings. However, it should be understood that various alternative variations may be assumed in the embodiments unless explicitly stated otherwise. It should also be understood that the specific devices shown in the drawings and described in the following description are merely exemplary embodiments of this disclosure. Therefore, the specific dimensions and other physical characteristics associated with the embodiments disclosed herein should not be considered limiting.

[0020] As used herein, the terms “first,” “second,” and “third” are used interchangeably to distinguish one component from another and are not intended to indicate the location or importance of the individual components.

[0021] The terms "front" and "rear" refer to relative positions within a gas turbine engine or vehicle, and specifically to the normal operating posture of the gas turbine engine or vehicle. For example, in the case of a gas turbine engine, "front" refers to the position closer to the engine inlet, while "rear" refers to the position closer to the engine nozzle or exhaust port.

[0022] The terms "upstream" and "downstream" refer to the relative directions of fluid flow within a fluid path. For example, "upstream" refers to the direction from which the fluid flows, and "downstream" refers to the direction from which the fluid flows.

[0023] Unless otherwise specified herein, the terms “connection,” “fixed,” “attached to,” etc., refer to both direct connection, fixation, or attachment, and indirect connection, fixation, or attachment via one or more intermediate components or features.

[0024] Unless the context clearly indicates otherwise, the singular forms “a,” “a,” and “the” include plural references.

[0025] In the context of, for example, “at least one of A, B and C” or “at least one of A, B or C”, the term “at least one” means only A, only B, only C, or any combination of A, B and C.

[0026] As used throughout the specification and claims, approximate language is applied to modify any quantitative expression that allows for variation without altering its underlying function. Therefore, values ​​modified by terms such as “about,” “approximate,” and “substantially” are not limited to specified exact values. In at least some cases, approximate language may correspond to the precision of the instrument used to measure the value, or the precision of the method or machine used to construct or manufacture the component and / or system. For example, approximate language may refer to margins of 1%, 2%, 4%, 10%, 15%, or 20%. These approximate margins may apply to a single value, to either end of a range defining a numerical value, or to margins between two ends, and / or between the ends.

[0027] Throughout this specification and claims, scope limitations are combined and interchanged, and unless the context or language otherwise indicates otherwise, such scopes are identified and include all subscopes contained herein. For example, all scopes disclosed herein include endpoints, and endpoints may be combined independently of each other.

[0028] As used herein, "third stream" refers to a non-mainstream flow that can increase fluid energy to generate a small amount of total propulsion thrust. The pressure ratio of the third stream can be higher than that of the main propulsion flow (e.g., bypass or propeller-driven propulsion flow). Thrust can be generated through dedicated nozzles or by mixing the airflow through the third stream with the main propulsion flow or core flow (e.g., mixing it into a common nozzle).

[0029] In some exemplary embodiments, the operating temperature of the airflow through the third flow can be below the engine's maximum compressor discharge temperature, and more specifically, below 350 degrees Fahrenheit (e.g., below 300 degrees Fahrenheit, below 250 degrees Fahrenheit, below 200 degrees Fahrenheit, and at least as high as ambient temperature). In some exemplary embodiments, these operating temperatures can facilitate heat transfer to or from the airflow through the third flow and the separate fluid flow. Furthermore, in some exemplary embodiments, under takeoff conditions, or more specifically, under operating conditions of sea-level rated takeoff power, static flight speed, and an ambient temperature of 86 degrees Fahrenheit, the airflow through the third flow can contribute less than 50% (and at least, for example, 2%) of the total engine thrust.

[0030] Furthermore, in some exemplary embodiments, the aforementioned exemplary percentage contribution of the third flow's airflow aspects (e.g., airflow, mixing, or exhaust properties) to the total thrust can be passively adjusted during engine operation or purposefully modified by using engine control features (such as fuel flow, motor power, variable stator, variable inlet guide vanes, valves, variable exhaust geometry, or fluid characteristics) to adjust or optimize overall system performance under a wide range of potential operating conditions.

[0031] The term “turbine” or “turbomachinery” refers to a machine that includes one or more compressors, a heating section (e.g., a combustion section), and one or more turbines that together generate torque output.

[0032] The term "gas turbine engine" refers to an engine that has a turbine as its power source, in whole or in part. Examples of gas turbine engines include turbofan engines, turboprop engines, turbojet engines, turboshaft engines, and hybrid electric versions of one or more of these engines.

[0033] When used with compressors, turbines, shafts, or spool components, unless otherwise specified, the terms “low” and “high,” or their respective comparatives (e.g., “lower” and “higher,” where applicable), refer to relative speeds within the engine. For example, “low-speed turbine” or “low-turbine” defines a component constructed to operate at a rotational speed (such as the maximum permissible rotational speed) lower than that of a “high-speed turbine” or “high-turbine” at the engine.

[0034] The term "equivalent ratio" refers to the ratio of the actual fuel / air ratio to the stoichiometric fuel / air ratio. Stoichiometric combustion occurs when all oxygen is consumed in the reaction and no molecular oxygen (O2) is found in the products.

[0035] If the equivalence ratio is equal to one, combustion is stoichiometric. If it is less than one, combustion is lean (lean fuel) with excess air, while if it is greater than one, combustion is rich (rich fuel) with incomplete combustion. The equivalence ratio is inversely related to the air-fuel ratio.

[0036] Exhaust from the aircraft's gas turbine consists of CO, carbon dioxide (CO2), water vapor (H2O), unburned hydrocarbons (UHC), particulate matter (mainly carbon), and NO. x And it consists of excess atmospheric oxygen and nitrogen. Limiting CO and NO in exhaust gases may be desirable. x Element.

[0037] Systems and methods for reducing emissions from aircraft propulsion systems using fuel cells are provided.

[0038] The aircraft may include an aircraft fuel supply unit. The propulsion system may include a fuel cell assembly defining operating parameters and including a fuel cell and, for example, an air handling unit, a fuel handling unit, and a power converter. The propulsion system may also include a turbine comprising a compressor section, a combustor, and a turbine section arranged in a sequential flow order. The combustor may be configured to receive an aviation fuel flow from the aircraft fuel supply unit and may be further configured to receive output products from the fuel cell.

[0039] The system further includes a controller. The controller is generally configured to receive data indicating fan speed or thrust requirements and burner temperature. The controller can determine a set of fuel cell operating conditions to meet thrust requirements and maintain burner temperature within temperature limits; and can further control fuel cell assembly operating parameters based on the determined set of fuel cell operating conditions to maintain burner temperature within temperature limits (e.g., emission temperature limits).

[0040] More specifically, the controller can determine a first set of fuel cell operating conditions in response to determining that the burner temperature is approaching or has dropped below the lower limit of the temperature range, and determine a second set of fuel cell operating conditions in response to determining that the burner temperature is approaching or has exceeded the upper limit of the temperature range.

[0041] In response to determining a first set of fuel cell operating conditions or a second set of operating conditions, the controller controls the operating parameters of the fuel cell assembly. In at least some exemplary aspects, it may include controlling at least one of an air handling unit, a fuel handling unit, and a power converter based on one of the first set of fuel cell operating conditions and the second set of fuel cell operating conditions.

[0042] Controlling the first set of fuel cell operating conditions (“cryogenic control”) may include increasing the burner temperature (e.g., flame temperature), which accelerates the oxidation rate and improves combustion efficiency, thus reducing carbon monoxide (CO) emissions. For example, control based on the first set of fuel cell operating conditions may include increasing the fuel cell exhaust temperature, increasing the equivalence ratio of output products from the fuel cell (e.g., hydrogen-rich fuel), increasing fuel utilization of the fuel cell (delivering less H2 fuel and more air to promote more complete combustion within the combustion chamber), and reducing direct fuel transfer from the fuel cell assembly to the burner.

[0043] Controlling the second set of fuel cell operating conditions (“high-temperature control method”) may include reducing the burner temperature (e.g., flame temperature), which provides the ability to quench nitrogen oxides (NOx). x The reaction produces a higher purity exhaust stream and / or is used as an evaporator to reduce NO. x Control based on the second set of fuel cell operating conditions may include increasing the current drawn from the fuel cell and directing or injecting combustion gases from the fuel cell toward or at the burner outlet. By increasing the current drawn from the fuel cell, more hydrogen is consumed in the fuel cell, and less fuel is emitted into the burner. By directing the combustion gases from the fuel cell toward the burner outlet, the residence time of the gas in the burner is reduced, thereby lowering NO levels. x .

[0044] The systems and methods disclosed herein can generally result in lower emissions while maintaining fan speed or thrust requirements. This emission reduction is provided while achieving fan speed or thrust requirements.

[0045] Referring now to the accompanying drawings, where the same numbers indicate the same elements throughout all the drawings. Figure 1A schematic cross-sectional view of an engine according to an exemplary embodiment of the present disclosure is provided. The engine can be integrated into a vehicle. For example, the engine can be an aircraft engine integrated into an aircraft. However, alternatively, the engine can be any other suitable type of engine for any other suitable vehicle.

[0046] In the depicted embodiment, the engine is configured as a high-bypass gas turbine engine 100. As... Figure 1 As shown, the gas turbine engine 100 defines an axial direction A (extending parallel to the centerline axis 101 provided for reference), a radial direction R, and a circumferential direction (extending around the axial direction A; not shown in the diagram). Figure 1 (As shown in the figure). Typically, the gas turbine engine 100 includes a fan section 102 and a turbine 104 disposed downstream of the fan section 102.

[0047] The depicted exemplary turbine 104 generally includes a substantially tubular housing 106 defining an annular inlet 108. The housing 106 surrounds, in a series flow relationship: a compressor section including a boost or low-pressure (LP) compressor 110 and a high-pressure (HP) compressor 112; a combustion section 114; a turbine section including a high-pressure (HP) turbine 116 and a low-pressure (LP) turbine 118; and an exhaust nozzle section 120. The compressor section, combustion section 114, and turbine section together at least partially define a core airflow path 121 extending from the annular inlet 108 to the exhaust nozzle section 120. The turbofan engine further includes one or more drive shafts. More specifically, the turbofan engine includes a high-pressure (HP) shaft or spool 122 drivingly connecting the HP turbine 116 to the HP compressor 112, and a low-pressure (LP) shaft or spool 124 drivingly connecting the LP turbine 118 to the LP compressor 110.

[0048] For the depicted embodiment, fan section 102 includes a fan 126 having a plurality of fan blades 128 spaced apart and coupled to disk 130. The fan blades 128 and disk 130 are rotatable together about a centerline axis 101 via LP shaft 124. Disk 130 is covered by a rotatable front hub 132, aerodynamically shaped to facilitate airflow through the plurality of fan blades 128. Furthermore, an annular fan housing or outer nacelle 134 is configured to circumferentially surround at least a portion of fan 126 and / or turbine 104. Nacelle 134 is supported relative to turbine 104 by a plurality of circumferentially spaced outlet guide vanes 136. A downstream section 138 of nacelle 134 extends over the outer portion of turbine 104 to define a bypass airflow passage 140 therebetween.

[0049] In this way, it will be understood that the gas turbine engine 100 generally includes a first flow (e.g., a core airflow path 121) and a second flow extending parallel to the first flow (e.g., a bypass airflow passage 140). In some exemplary embodiments, the gas turbine engine 100 may further define a third flow, for example, extending from the LP compressor 110 to the bypass airflow passage 140 or to the environment. With this configuration, the LP compressor 110 may generally include a first compressor stage configured as a ducted intermediate fan and a downstream compressor stage. The inlet of the third flow may be located between the first compressor stage and the downstream compressor stage.

[0050] Still referencing Figure 1 The gas turbine engine 100 further includes an accessory gearbox 142 and a fuel delivery system 146. In the illustrated embodiment, the accessory gearbox 142 is located within the shroud / casing 106 of the turbine 104. Furthermore, it will be understood that for... Figure 1 In the schematically depicted embodiment, accessory gearbox 142 is mechanically coupled to one or more shafts or spools of turbine 104 and is rotatable with one or more shafts or spools of turbine 104. For example, in the depicted exemplary embodiment, accessory gearbox 142 is mechanically coupled to HP shaft 122 via a suitable gear train 144 and is rotatable with HP shaft 122. Accessory gearbox 142 can provide power to one or more suitable accessory systems of gas turbine engine 100 during at least some operations and can further provide power back to gas turbine engine 100 during other operations. For example, in the illustrated embodiment, accessory gearbox 142 is coupled to starter motor / generator 152. Starter motor / generator can be configured to draw power from accessory gearbox 142 and gas turbine engine 100 to generate electricity during some operations and can provide power back to accessory gearbox 142 and gas turbine engine 100 (e.g., to HP shaft 122) during other operations to add mechanical work back to gas turbine engine 100 (e.g., for starting gas turbine engine 100).

[0051] Furthermore, the fuel delivery system 146 generally includes a fuel source 148 (such as a fuel tank) and one or more fuel delivery lines 150. One or more fuel delivery lines 150 supply fuel flow through the fuel delivery system 146 to the combustion section 114 of the turbine 104 of the gas turbine engine 100. As will be discussed in more detail below, the combustion section 114 includes an integrated fuel cell and combustor assembly 200. In the described embodiment, one or more fuel delivery lines 150 supply fuel flow to the integrated fuel cell and combustor assembly 200.

[0052] However, it will be understood that, Figure 1The exemplary gas turbine engine 100 depicted is provided by way of example only. In other exemplary embodiments, any other suitable gas turbine engine may be used in conjunction with aspects of this disclosure. For example, in other embodiments, the turbofan engine may be any other suitable gas turbine engine, such as a turboshaft engine, a turboprop engine, a turbojet engine, etc. In this way, it will be further understood that in other embodiments, the gas turbine engine may have any other suitable construction, such as any other suitable number or arrangement of shafts, compressors, turbines, fans, etc. Furthermore, although Figure 1 The exemplary gas turbine engine depicted herein is schematically shown as a direct-drive fixed-pitch turbofan engine, but in other embodiments, the gas turbine engine of this disclosure may be a geared gas turbine engine (i.e., including a gearbox between a fan 126 and a shaft (such as LP shaft 124) driving the fan), a variable-pitch gas turbine engine (i.e., including a fan 126 having a plurality of fan blades 128 capable of rotating about their respective pitch axes), etc. Furthermore, although the exemplary gas turbine engine 100 includes a ducted fan 126, in other exemplary aspects, the gas turbine engine 100 may include a non-ducted fan 126 (or an open rotor fan) without a nacelle 134. Moreover, although not depicted herein, in other embodiments, the gas turbine engine may be any other suitable type of gas turbine engine, such as a marine gas turbine engine.

[0053] Now for reference Figure 2 , Figure 2 A portion of a combustion section 114 according to an embodiment of the present disclosure is schematically shown, which includes Figure 1 The gas turbine engine 100 (as mentioned above) Figure 1 Described as part of the integrated fuel cell and burner assembly 200 used in a gas turbine engine 100.

[0054] It will be understood that the combustion section 114 includes a compressor diffuser nozzle 202 and extends generally along the axial direction A between an upstream end and a downstream end. The combustion section 114 is fluidly connected via the compressor diffuser nozzle 202 to the compressor section at the upstream end and to the turbine section at the downstream end.

[0055] The integrated fuel cell and burner assembly 200 generally includes fuel cell assembly 204. Figure 2 Only a partial description is provided; see also Figures 3 to 5The combustor 206 includes an inner liner 208, an outer liner 210, a dome assembly 212, a shroud assembly 214, a swirler assembly 216, and a fuel flow line 218. The combustion section 114 generally includes a housing 220 radially outward of the combustor 206 to surround it, and an inner housing 222 radially inward of the combustor 206. The inner housing 222 and the inner liner 208 define an inner passage 224 therebetween, while the housing 220 and the outer liner 210 define an outer passage 226 therebetween. The inner housing 222, the housing 220, and the dome assembly 212 together at least partially define the combustion chamber 228 of the combustor 206.

[0056] The dome assembly 212 is positioned near the upstream end of the combustion section 114 (i.e., closer to the upstream end than the downstream end) and includes an opening (not labeled) for receiving and retaining the swirler assembly 216. The swirler assembly 216 also includes an opening for receiving and retaining the fuel flow line 218. The fuel flow line 218 is further coupled to a fuel source 148 disposed radially R outside the housing 220 (see [link to fuel source 148]). Figure 1 It is configured to receive fuel from fuel source 148. In this way, fuel flow line 218 can be fluidly connected to the above reference. Figure 1 Describes one or more fuel delivery pipelines 150.

[0057] The swirler assembly 216 may include a plurality of swirlers (not shown) configured to swirl the compressed fluid before it is injected into the combustion chamber 228 to generate combustion gases. In the illustrated embodiment, the shroud assembly 214 is configured to hold the inner liner 208, the outer liner 210, the swirler assembly 216, and the dome assembly 212 together.

[0058] During operation, the compressor diffuser nozzle 202 is configured to direct compressed fluid 230 from the compressor section to the combustor 206, wherein the compressed fluid 230 is configured to mix with fuel within the cyclone assembly 216 and burn within the combustion chamber 228 to generate combustion gases. The combustion gases are supplied to the turbine section to drive one or more turbines of the turbine section (e.g., high-pressure turbine 116 and low-pressure turbine 118).

[0059] During operation of the gas turbine engine 100, which includes an integrated fuel cell and combustor assembly 200, the flame within the combustion chamber 228 is maintained by a continuous flow of fuel and air. To provide ignition of the fuel and air, for example during start-up of the gas turbine engine 100, the integrated fuel cell and combustor assembly 200 further includes an igniter 231. The igniter 231 can provide a spark or initial flame to ignite the fuel and air mixture within the combustion chamber 228. In some exemplary embodiments, the integrated fuel cell and combustor assembly 200 may additionally include a dedicated fuel cell igniter 233 (depicted in dashed lines). Specifically, for Figure 2 In one embodiment, a dedicated fuel cell igniter 233 is positioned downstream of at least a portion of the fuel cell, particularly downstream of at least a portion of the fuel cell stack (described below). In this way, the dedicated fuel cell igniter 233 can more efficiently combust the fuel cell's output products.

[0060] As mentioned above and Figure 2 The diagram schematically depicts an integrated fuel cell and burner assembly 200, which further includes a fuel cell assembly 204. The depicted exemplary fuel cell assembly 204 includes a first fuel cell stack 232 and a second fuel cell stack 234. More specifically, the first fuel cell stack 232 is constructed together with an outer liner 210, and the second fuel cell stack 234 is constructed together with an inner liner 208. Even more specifically, the first fuel cell stack 232 is integrated with the outer liner 210, and the second fuel cell stack 234 is integrated with the inner liner 208. The operation of the fuel cell assembly 204, and more specifically, the operation of the fuel cell stacks (e.g., the first fuel cell stack 232 or the second fuel cell stack 234) of the fuel cell assembly 204, will be described in more detail below.

[0061] In the described embodiments, fuel cell assembly 204 is configured as a solid oxide fuel cell (“SOFC”) assembly, wherein a first fuel cell stack 232 is configured as a first SOFC fuel cell stack, and a second fuel cell stack 234 is configured as a second SOFC fuel cell stack (each having multiple SOFCs). It will be understood that an SOFC is generally an electrochemical conversion device that generates electricity directly by oxidizing fuel. Generally, fuel cell assemblies, and especially fuel cells, are characterized by the electrolyte material used. The SOFCs of this disclosure generally may include solid oxide or ceramic electrolytes. Such fuel cells generally exhibit high overall thermoelectric efficiency, long-term stability, fuel flexibility, and low emissions.

[0062] In some embodiments, fuel cell assembly 204 includes a plurality of fuel cell stacks distributed along the axial direction A of burner 206. The fuel to the plurality of fuel cell stacks (e.g., from fuel source 148 or elements of the fuel cell and burner assembly 200 described herein) may be varied to distribute fuel to burner 206 along the axial direction A of burner 206.

[0063] For example, the "late lean" method uses more fuel to burn at the downstream end of burner 206. The "late lean" method can be implemented to reduce the residence time of fuel in burner 206.

[0064] For illustrative purposes, the second fuel cell stack 234 includes an upstream fuel cell stack 234A and a downstream fuel cell stack 234B. The fuel flow from the fuel source 148 to the upstream fuel cell stack 234A can be controlled by valve 235A, and the fuel flow from the fuel source 148 to the downstream fuel cell stack 234B can be controlled by valve 235B. It should be understood that the first fuel cell stack 232 can be similarly arranged in a distribution along the axial direction A.

[0065] Additionally or alternatively, in other exemplary embodiments, the first fuel cell stack 232 and the second fuel cell stack 234 may be arranged along the circumferential direction of the combustion chamber 228 (see [reference]). Figure 3 Furthermore, in other exemplary embodiments, fuel cell assembly 204 may include any other suitable number and arrangement of fuel cell stacks to distribute output products at various locations with different parameters (e.g., temperature, pressure, composition, etc.) along the axial and circumferential directions of combustion chamber 228.

[0066] Furthermore, the exemplary fuel cell assembly 204 further includes a first power converter 236 and a second power converter 238. The first fuel cell stack 232 is electrically connected to the first power converter 236 via a first plurality of power cables (unlabeled), and the second fuel cell stack 234 is electrically connected to the second power converter 238 via a second plurality of power cables (unlabeled).

[0067] The first power converter 236 controls the current drawn from the corresponding first fuel cell stack 232 and can convert direct current (“DC”) power to DC power or alternating current (“AC”) power at another voltage level. Similarly, the second power converter 238 controls the current drawn from the second fuel cell stack 234 and can convert DC power to DC power or AC power at another voltage level. The first power converter 236, the second power converter 238, or both can be electrically connected to an electrical bus (such as electrical bus 326 described below).

[0068] The integrated fuel cell and burner assembly 200 further includes a fuel cell controller 240, which is operatively communicable with a first power converter 236 and a second power converter 238 to send and receive communications and signals, for example, between the two. For example, the fuel cell controller 240 can send current or power setpoint signals to the first power converter 236 and the second power converter 238, and can receive voltage or current feedback signals, for example, from the first power converter 236 and the second power converter 238. The fuel cell controller 240 can be configured in accordance with the following references. Figure 5 The controller 240 described is constructed in the same manner.

[0069] As will be discussed in more detail below, a fuel cell is an electrochemical device that converts the chemical energy from a fuel (such as hydrogen) into electrical energy through an electrochemical reaction between the fuel and an oxidant (such as oxygen contained in the atmosphere). Fuel cell systems can be advantageously used as energy supply systems because, compared to at least some existing systems, they can be considered environmentally superior and highly efficient.

[0070] To improve system efficiency and fuel utilization while reducing external water consumption, fuel cell systems may include an anode recirculation loop. Since a single fuel cell can only generate approximately 1V of voltage, multiple fuel cells can be stacked together (which can be called a fuel cell stack) to generate the desired voltage. Fuel cells can include solid oxide fuel cells (SOFC), molten carbonate fuel cells (MCFC), phosphoric acid fuel cells (PAFC), and proton exchange membrane fuel cells (PEMFC), which are generally named after their respective electrolytes.

[0071] It will be understood that, in at least some exemplary embodiments, the first fuel cell stack 232, the second fuel cell stack 234, or both may extend substantially 360 degrees in the circumferential direction C of the gas turbine engine (i.e., the direction in which it extends about the centerline axis 101 of the gas turbine engine 100). For example, now referring to... Figure 3 A simplified cross-sectional view of an integrated fuel cell and burner assembly 200 is depicted according to an exemplary embodiment of this disclosure. Although for simplicity... Figure 3 Only the first fuel cell stack 232 is depicted, but the second fuel cell stack 234 can be constructed in a similar manner.

[0072] As shown in the figure, the first fuel cell stack 232 extends around the combustion chamber 228 in the circumferential direction C, and in the illustrated embodiment, completely surrounds the combustion chamber 228 around the central axis 101. More specifically, the first fuel cell stack 232 includes a plurality of fuel cells 242 arranged in the circumferential direction C. Figure 3The fuel cell 242 visible in the image can be a single ring of fuel cell 242, wherein fuel cells 242 are stacked together along the axial direction A (see [link]). Figure 2 ( ), to form a first fuel cell stack 232. In another example, multiple additional rings of fuel cell 242 may be placed on top of each other to form a first fuel cell stack 232 extending along the centerline axis 101.

[0073] The following will explain this in more detail; please refer to [reference needed]. Figure 5 In the first fuel cell stack 232, fuel cell 242 is positioned to receive exhaust air 244 from, for example, a compressor section and fuel 246 from a fuel delivery system 146. Fuel cell 242 uses the air 244 and at least some of the fuel 246 to generate an electric current and guides partially oxidized fuel 246 and unused portion of air 248 radially toward the centerline axis 101 into combustion chamber 228. Integrated fuel cell and combustor assembly 200 combusts the partially oxidized fuel 246 and air 248 in combustion chamber 228 into combustion gases, which are then guided downstream into a turbine section to drive or assist in driving one or more turbines therein.

[0074] In addition, now refer to Figure 4 Provided as Figure 2 A schematic perspective view of the first fuel cell stack 232 of the integrated fuel cell and burner assembly 200. The second fuel cell stack 234 can be formed in a similar manner.

[0075] The depicted first fuel cell stack 232 includes a casing 250 having a combustion outlet side 252 and a side 254 opposite to the combustion outlet side 252, a fuel and air inlet side 256 and a side 588 opposite to the fuel and air inlet side 256, and sides 260 and 262. Sides 260, 258, and 254 are... Figure 4 It is not visible in the 3D image.

[0076] It will be understood that the first fuel cell stack 232 may include, for example, multiple fuel cells “stacked” side-by-side from one end of the first fuel cell stack 232 (e.g., fuel and air inlet side 256) to the other end of the first fuel cell stack 232 (e.g., side 258). Therefore, it will be further understood that the combustion outlet side 252 includes multiple combustion outlets 264, each combustion outlet originating from a fuel cell within the first fuel cell stack 232. During operation, combustion gases 266 (also referred to herein as “output products”) are directed from the combustion outlets 264 out of the housing 250. As described herein, the combustion gases 266 are generated using fuel and air not consumed by the fuel cells within the housing 250 of the first fuel cell stack 232. The combustion gases 266 are supplied to the combustion chamber 228 and combusted during operation to generate combustion gases used to generate thrust for the gas turbine engine 100 (and vehicles / aircraft in conjunction with the gas turbine engine 100).

[0077] The fuel and air inlet side 256 includes one or more fuel inlets 268 and one or more air inlets 270. Optionally, one or more of the inlets 268, 270 may be located on the other side of the housing 250. Each of the one or more fuel inlets 268 is fluidly connected to a fuel source (such as hydrogen gas or one or more pressurized containers of a fuel processing unit further described below) for the first fuel cell stack 232. Each of the one or more air inlets 270 is fluidly connected to an air source (such as air discharged from the compressor section and / or the air processing unit also further described below) for the fuel cell. The one or more inlets 268, 270 separately receive fuel and air from external fuel and air sources and separately direct the fuel and air into the fuel cell.

[0078] In some exemplary embodiments, Figures 2 to 4 The first fuel cell stack 232 may be constructed in a manner similar to one or more of the exemplary fuel cell systems (labeled 100) described, for example, in U.S. Patent Application Publication No. 2020 / 0194799A1, filed December 17, 2018, the entire contents of which are incorporated herein by reference. It will be further understood that... Figure 2 The second fuel cell stack 234 can be constructed in a similar manner to the first fuel cell stack 232, or alternatively, it can be constructed in any other suitable manner.

[0079] Now for reference Figure 5 The operation of an integrated fuel cell and burner assembly 200 (e.g., a fuel cell assembly) according to exemplary embodiments of the present disclosure will be described. More specifically, Figure 5A schematic diagram of a gas turbine engine 100 and an integrated fuel cell and combustor assembly 200 according to embodiments of the present disclosure is provided. In some exemplary embodiments, the gas turbine engine 100 and the integrated fuel cell and combustor assembly 200 can be coupled with… Figures 1 to 4 One or more exemplary embodiments are constructed in a similar manner to those described above.

[0080] Therefore, it will be understood that the gas turbine engine 100 generally includes a fan section 102 with a fan 126, an LP compressor 110, an HP compressor 112, a combustion section 114, an HP turbine 116, and an LP turbine 118. The combustion section 114 generally includes an integrated fuel cell and combustor assembly 200 with a combustor 206 and a fuel cell assembly 204.

[0081] The propulsion system including the gas turbine engine 100 further includes a fuel delivery system 146. The fuel delivery system 146 generally includes a fuel source 148 and one or more fuel delivery lines 150. The fuel source 148 may include a supply section for fuel (e.g., hydrocarbon fuel, including, for example, carbon-neutral fuel or synthetic hydrocarbons) for the gas turbine engine 100. Furthermore, it will be understood that the fuel delivery system 146 also includes a fuel pump 272 and a distributor 274, and the one or more fuel delivery lines 150 include a first fuel delivery line 150A, a second fuel delivery line 150B, and a third fuel delivery line 15C.

[0082] Diverter 274 divides the fuel flow from fuel source 148 and fuel pump 272 into a first fuel flow through a first fuel delivery line 150A to fuel cell assembly 204, a second fuel flow through a second fuel delivery line 150B also to fuel cell assembly 204 (and particularly to the air handling unit described below), and a third fuel flow through a third fuel delivery line 150C to burner 206. Diverter 274 may include a series of valves (not shown) to facilitate this diversion of the fuel flow from fuel source 148, or alternatively, may have a fixed geometry. Furthermore, for the illustrated embodiment, fuel delivery system 146 includes a first fuel valve 151A associated with the first fuel delivery line 150A (e.g., for controlling the first fuel flow), a second fuel valve 151B associated with the second fuel delivery line 150B (e.g., for controlling the second fuel flow), and a third fuel valve 151C associated with the third fuel delivery line 150C (e.g., for controlling the third fuel flow).

[0083] The gas turbine engine 100 further includes a compressor exhaust system and an airflow delivery system. More specifically, the compressor exhaust system includes an LP bleed air duct 276 and an associated LP bleed air valve 278, an HP bleed air duct 280 and an associated HP bleed air valve 282, and an HP outlet air duct 284 and an associated HP outlet air valve 286.

[0084] The gas turbine engine 100 further includes an air supply duct 288 (in airflow communication with the air supply unit 290) and an associated air valve 292, which is also in airflow communication with the air delivery system, for providing compressed airflow to the fuel cell assembly 204 of the integrated fuel cell and combustor assembly 200. The air supply unit may be, for example, a second gas turbine engine configured to provide cross-bleed air, an auxiliary power unit (APU) configured to provide bleed air, a ram air turbine (RAT), etc. If the compressor air source is insufficient or unavailable, the air supply unit may supplement the compressor exhaust system.

[0085] The compressor discharge system (and air supply duct 288) is in airflow communication with the airflow delivery system for supplying compressed airflow to the fuel cell assembly 204, as will be explained in more detail below.

[0086] Still referencing Figure 5 The fuel cell assembly 204, which integrates the fuel cell and burner assembly 200, includes a fuel cell stack 294, which can be constructed in a manner similar to, for example, the first fuel cell stack 232 described above. The fuel cell stack 294 is schematically depicted as a single fuel cell having a cathode side 296, an anode side 298, and an electrolyte 300 positioned between them. Generally, it will be understood that the electrolyte 300 can conduct negative oxygen ions from the cathode side 296 to the anode side 298 during operation to generate current and electricity.

[0087] The anode side 298 can support an electrochemical reaction that generates electricity. Fuel can be oxidized in the anode side 298 via diffusion through the electrolyte 300, utilizing oxygen ions received from the cathode side 296. This reaction can generate heat, vapor, and electricity in the form of free electrons in the anode side 298, which can be used to power energy-consuming devices (such as one or more additional electrical devices 328 described below). Oxygen ions can be generated using electrons returning from the energy-consuming device to the cathode side 296 via oxygen reduction of the cathode oxidant.

[0088] The cathode side 296 can be coupled to a cathode oxidant source, such as atmospheric oxygen. The cathode oxidant is defined as the oxidant supplied to the cathode side 296, which is used by the fuel cell system to generate electricity. The cathode side 296 can be permeable to oxygen ions received from the cathode oxidant.

[0089] Electrolyte 300 can be connected to both the anode side 298 and the cathode side 296. Electrolyte 300 allows oxygen ions to pass from the cathode side 296 to the anode side 298, and can have very low conductivity or no conductivity to prevent free electrons from passing from the cathode side 296 to the anode side 298.

[0090] The anode side of a solid oxide fuel cell (such as fuel cell stack 294) can be made of nickel / yttrium oxide-stabilized zirconium oxide (Ni / YSZ) cermet. Nickel in the anode side serves as a catalyst for fuel oxidation and a current conductor. During normal operation of fuel cell stack 294, the operating temperature can be greater than or equal to approximately 700°C, and the nickel (Ni) in the anode retains its reduced form due to the continuous supply of primarily hydrogen fuel gas.

[0091] Simply put, it will be understood that the fuel cell assembly 204 further includes a fuel cell sensor 302 configured to sense data indicating operating parameters of the fuel cell assembly, such as the temperature of the fuel cell stack 294 (e.g., the cathode side 296 or anode side 298 of the fuel cell) and the pressure within the fuel cell stack 294 (e.g., within the cathode side 296 or anode side 298 of the fuel cell).

[0092] The fuel cell stack 294 is located downstream of the LP compressor 110, the HP compressor 112, or both. Furthermore, from the above regarding... Figure 2 As will be understood from the description, fuel cell stack 294 may be coupled to or otherwise integrated with the bushings (e.g., inner liner 208 or outer liner 210) of burner 206. In this way, fuel cell stack 294 may also be arranged upstream of combustion chamber 228, which integrates fuel cell and burner assembly 200, and further upstream of HP turbine 116 and LP turbine 118.

[0093] like Figure 5 As shown, the fuel cell assembly 204 also includes a fuel processing unit 304 and an air processing unit 306. In the exemplary embodiment depicted, the fuel processing unit 304 and the air processing unit 306 are manifolded together within the housing 308 to provide conditioned air and fuel to the fuel cell stack 294.

[0094] The fuel processing unit 304 can be any suitable structure for generating a hydrogen-rich fuel stream. For example, the fuel processing unit 304 may include a fuel reformer or a catalytic partial oxidation converter (CPO). x ), used to generate a hydrogen-rich fuel stream for fuel cell stack 294.

[0095] However, it should be understood that the fuel processing unit 304 may additionally or alternatively include any suitable type of fuel reformer, such as an automatic thermal reformer and a steam reformer, which may require an additional steam inlet stream with a higher hydrogen composition at the reformer outlet stream. Additionally or alternatively, the fuel processing unit 304 may also include a reformer integrated with the fuel cell stack 294.

[0096] The air handling unit 306 can be any suitable structure for raising the temperature of the air supplied to it to a temperature sufficiently high to achieve fuel cell temperature control (e.g., about 600°C to about 800°C). For example, in the depicted embodiment, the air handling unit includes a pre-burner system that operates based on a fuel flow through a second fuel delivery line 150B and is configured to raise the temperature of the air by combustion, for example, during transient conditions such as start-up, shutdown, and abnormal situations.

[0097] Similarly, it should be understood that Figure 5 The air handling unit 306 may alternatively be a heat exchanger or another device for raising the temperature of the air supplied thereto to a temperature high enough to achieve fuel cell temperature control (e.g., about 600°C to about 800°C).

[0098] As described above, the compressor discharge system (and air supply duct 288) is in airflow communication with the airflow delivery system for providing compressed airflow to the fuel cell assembly 204. The airflow delivery system includes an anode airflow duct 310 and associated anode airflow valve 312 for providing airflow to the fuel processing unit 304, a cathode airflow duct 314 and associated cathode airflow valve 316 for providing airflow to the air processing unit 306, and a cathode bypass air duct 318 and associated cathode bypass air valve 320 for providing airflow directly to the fuel cell stack 294 (or more precisely, to the cathode side 296 of the fuel cell). The fuel delivery system 146 is configured to provide a first fuel flow to the fuel processing unit 304 via a first fuel delivery line 150A and a second fuel flow to the air processing unit 306 via a second fuel delivery line 150B (e.g., as fuel for the pre-combustor system, if provided).

[0099] The fuel cell stack 294 outputs electricity as the fuel cell power output 322. In addition, the fuel cell stack 294 directs cathode air emissions and anode fuel emissions (not labeled for clarity) into the combustion chamber 228 of the burner 206.

[0100] In operation, the air treatment unit 306 is configured to heat / cool a portion of the compressed air entering through the cathode airflow duct 314 to generate treated air to be guided into the fuel cell stack 294, thereby facilitating the operation of the fuel cell stack 294. The air treatment unit 306 receives a second fuel flow from the second fuel delivery line 150B and can, for example, combust this second fuel flow to heat the received air to a desired temperature (e.g., about 600°C to about 800°C), thereby facilitating the operation of the fuel cell stack 294. The air treated by the air treatment unit 306 is guided into the fuel cell stack 294. In embodiments of this disclosure, as shown, the cathode bypass air duct 318 and the air treated by the air treatment unit 306 can be combined into a combined airflow to be fed into the cathode 296 of the fuel cell stack 294.

[0101] In addition, such as Figure 5 As shown in the embodiment, a first fuel flow via a first fuel delivery line 150A is directed to a fuel processing unit 304 for generating a hydrogen-rich fuel flow (e.g., optimizing the hydrogen content of the fuel flow), which is also fed into the fuel cell stack 294. It will be understood, and discussed below, that the air (processing air and bypass air) flow to the fuel cell stack 294 (e.g., cathode side 296) and the fuel from the fuel processing unit 304 to the fuel cell stack 294 (e.g., anode side 298) can facilitate power generation.

[0102] Since the inlet air to the fuel cell stack 294 may originate solely from the upstream compressor section without any other separately controlled air source, it will be understood that the inlet air to the fuel cell stack 294 discharged from the compressor section will be affected by air temperature variations occurring at different stages of flight. As an illustrative example only, the air in a specific location within the compressor section of the gas turbine engine 100 may operate at 200°C during idling, 600°C during takeoff, 268°C during cruise, and so on. This type of temperature variation in the inlet air directed to the fuel cell stack 294 can cause significant thermal transient problems (or even thermal shock) to the ceramic material of the fuel cell stack 294, potentially ranging from cracking to failure.

[0103] Therefore, by fluidly connecting the air handling unit 306 between the compressor section and the fuel cell stack 294, the air handling unit 306 can serve as a control device or system to maintain the air processed by the air handling unit 306 and directed into the fuel cell stack 294 within a desired operating temperature range (e.g., ±100°C, or preferably ±50°C, or ±20°C). During operation, the temperature of the air supplied to the fuel cell stack 294 (relative to the temperature of the air discharged from the compressor section) can be controlled by controlling the fuel flow to the air handling unit 306. Increasing the fuel flow to the air handling unit 306 can raise the temperature of the airflow to the fuel cell stack 294. Decreasing the fuel flow to the air handling unit 306 can lower the temperature of the airflow to the fuel cell stack 294. Optionally, fuel cannot be supplied to the air handling unit 306 to prevent the air handling unit 306 from raising and / or lowering the temperature of the air discharged from the compressor section and directed into the air handling unit 306.

[0104] Furthermore, as depicted in dashed lines, the fuel cell assembly 204 further includes an airflow bypass duct 321 extending around the fuel cell stack 294 to allow part or all of the airflow regulated by the air handling unit 306 (and combined with any bypass air passing through duct 318) to bypass the cathode side 296 of the fuel cell stack 294 and enter directly into the combustion chamber 228. The airflow bypass duct 321 may be in thermal communication with the fuel cell stack 294. The fuel cell assembly further includes a fuel bypass duct 323 extending around the fuel cell stack 294 to allow part or all of the reformed fuel from the fuel handling unit 304 to bypass the anode side 298 of the fuel cell stack 294 and enter directly into the combustion chamber 228.

[0105] As briefly mentioned above, the fuel cell stack 294 converts the anode fuel stream from the fuel processing unit 304 and the air processed by the air processing unit 306 into electrical energy in the form of DC current, i.e., fuel cell power output 322. This fuel cell power output 322 is directed to a power converter 324 to convert the DC current into DC or AC current that can be efficiently utilized by one or more subsystems. Specifically, in the depicted embodiment, power is supplied from the power converter to an electrical bus 326. The electrical bus 326 may be an electrical bus dedicated to the gas turbine engine 100, an electrical bus of an aircraft in conjunction with the gas turbine engine 100, or a combination thereof. The electrical bus 326 is electrically connected to one or more auxiliary electrical devices 328, which may be adapted to draw current from the fuel cell stack 294 or apply an electrical load to the fuel cell stack 294. The one or more auxiliary electrical devices 328 may be a power source, a power sink, or both. For example, the auxiliary electrical device 328 may be an energy storage device (such as one or more batteries), an electric motor (generator, electric motor, or both), an electric propulsion device, etc. For example, one or more auxiliary electrical devices 328 may include a starter motor / generator of the gas turbine engine 100.

[0106] Still referencing Figure 5 The gas turbine engine 100 further includes a sensor 330. In the illustrated embodiment, the sensor 330 is configured to sense data indicating the flame within the combustion section 114 of the gas turbine engine 100. For example, the sensor 330 may be a temperature sensor configured to sense data indicating the outlet temperature of the combustion section 114, the inlet temperature of the turbine section, the exhaust temperature, or a combination thereof. Additionally or alternatively, the sensor 330 may be any other suitable sensor or any suitable combination of sensors configured to sense one or more gas turbine engine operating conditions or parameters, including data indicating the flame within the combustion section 114 of the gas turbine engine 100.

[0107] In addition, such as Figure 5 Further schematically depicted, the propulsion system, the aircraft including the propulsion system, or both include controller 240. For example, controller 240 may be a standalone controller, a gas turbine engine controller (e.g., a full authority digital engine controller or a FADEC controller), an aircraft controller, a supervisory controller for the propulsion system, or combinations thereof.

[0108] The controller 240 is operatively connected to various sensors, valves, etc., within at least one of the gas turbine engine 100, the fuel delivery system 146, and the fuel cell and combustor assembly 200. More specifically, for the exemplary aspects depicted, the controller 240 is operatively connected to the air handling unit 306, the fuel handling unit 304, the power converter 324 (and / or the power converters 236m, 238), the valves (e.g., valves 235A, 235B) of the axially distributed fuel cell stacks (e.g., fuel cell stacks 234A, 234B), the valves (valve 278, 282, 286) of the compressor discharge system, the valves (valve 312, 316, 320) of the airflow delivery system, and the valves (splitter 274, valves 151A, 151B, 151C) of the fuel delivery system 146, as well as the sensor 330 of the gas turbine engine 100 and the fuel cell sensor 302.

[0109] As will be understood from the following description, controller 240 can communicate with these components via wired or wireless communication. In this way, controller 240 can receive inputs from various sources (including...). Figure 6 Data from the supervisory controller 412, gas turbine engine sensor 330, and fuel cell sensor 302 shown can be used to make control decisions and can provide data (e.g., instructions) to various outputs, including valves of the compressor discharge system that control the airflow from the compressor section, the airflow delivery system that guides the airflow from the compressor section, and the fuel delivery system 146 that guides the fuel flow within the gas turbine engine 100.

[0110] Referring specifically to the operation of controller 240, in at least some embodiments, controller 240 may include one or more computing devices 332. Computing device 332 may include one or more processors 332A and one or more memory devices 332B. The one or more processors 332A may include any suitable processing means, such as a microprocessor, microcontroller, integrated circuit, logic device, and / or other suitable processing means. The one or more memory devices 332B may include one or more computer-readable media, including but not limited to non-transitory computer-readable media, RAM, ROM, hard disk drives, flash drives, and / or other memory devices.

[0111] One or more memory devices 332B may store information accessible by one or more processors 332A, including computer-readable instructions 332C executable by one or more processors 332A. Instructions 332C may be any set of instructions that, when executed by one or more processors 332A, cause one or more processors 332A to operate. In some embodiments, instructions 332C may be executed by one or more processors 332A to cause one or more processors 332A to operate, such as any operations and functions configured for the controller 240 and / or computing device 332, operations for operating the propulsion system as described herein (e.g., method 600), and / or any other operations or functions of one or more computing devices 332. Instructions 332C may be software written in any suitable programming language or may be implemented in hardware. Additionally and / or alternatively, instructions 332C may be executed in logically and / or virtually decoupled threads on the processor 332A. Memory device 332B may further store data 332D accessible by processor 332A. For example, data 332D may include data indicating power flow, data indicating operating conditions of the gas turbine engine 100 / aircraft, and / or any other data and / or information described herein.

[0112] The computing device 332 also includes a network interface 332E, which is configured to communicate, for example, with other components of the gas turbine engine 100 (such as valves of the compressor exhaust system (valve 278, 282, 286), valves of the airflow delivery system (valve 312, 316, 320), and valves of the fuel delivery system 146 (splitter 274, valves 151A, 151B, 151C), as well as sensors 330 and fuel cell sensors 302 of the gas turbine engine 100), and with an aircraft associated with the gas turbine engine 100. The network interface 332E may include any suitable components for communication with one or more network interfaces, including, for example, transmitters, receivers, ports, controllers, antennas, and / or other suitable components. In this way, it will be understood that the network interface 332E can utilize any suitable combination of wired and wireless communication networks.

[0113] The techniques discussed in this paper refer to computer-based systems, actions taken by computer-based systems, and information sent to and from computer-based systems. It will be understood that the inherent flexibility of computer-based systems allows for a wide variety of possible configurations, combinations, and divisions of tasks and functionalities between and within components. For example, the processes discussed herein can be implemented using a single computing device or multiple computing devices working in combination. Databases, memory, instructions, and applications can be implemented on a single system or distributed across multiple systems. Distributed components can operate sequentially or in parallel.

[0114] As briefly described above, the fuel cell assembly 204 can be electrically connected to an electrical bus 326, which can be the electrical bus of the gas turbine engine 100, the electrical bus of an aircraft, or a combination thereof. Now, briefly refer to... Figure 6 The present disclosure provides a schematic diagram of an aircraft 400 according to an embodiment of the present disclosure, the aircraft 400 including one or more gas turbine engines 100 (designated 100A and 100B), each engine having an integrated fuel cell and combustor assembly 200 (designated 200A and 200B), and an aircraft electrical bus 326 electrically connected to the one or more gas turbine engines 100.

[0115] Specifically, for the described exemplary embodiment, the aircraft 400 is provided as including a fuselage 402, a tail 404, a first wing 406, a second wing 408, and a propulsion system. The propulsion system generally includes a first gas turbine engine 100A coupled to or integrated with the first wing 406 and a second gas turbine engine 100B coupled to or integrated with the second wing 408. However, it will be understood that in other embodiments, any other suitable number and / or configuration of gas turbine engines 100 may be provided (e.g., mounted on the fuselage, mounted on the tail, etc.).

[0116] The first gas turbine engine 100A generally includes a first integrated fuel cell and combustor assembly 200A and a first electric motor 410A. The first integrated fuel cell and combustor assembly 200A may generally include a first fuel cell assembly. The first electric motor 410A may be an embedded motor, an offset motor (e.g., capable of rotating with the gas turbine engine 100A via an accessory gearbox or suitable gear train), etc. For example, in some exemplary embodiments, the first electric motor 410A may be a starter motor / generator of the first gas turbine engine 100A.

[0117] Similarly, the second gas turbine engine 100B generally includes a second integrated fuel cell and combustor assembly 200B and a second electric motor 410B. The second integrated fuel cell and combustor assembly 200B may generally include a second fuel cell assembly. The second electric motor 410B may also be an embedded motor, an offset motor (e.g., capable of rotating with the gas turbine engine 100 via an accessory gearbox or suitable gear train), etc. For example, in some exemplary embodiments, the second electric motor 410B may be a starter motor / generator of the second gas turbine engine 100B.

[0118] exist Figure 6In this embodiment, the aircraft 400 additionally includes an electrical bus 326 and a supervisory controller 412. Furthermore, it will be understood that the aircraft 400 and / or propulsion system include one or more electrical devices 414 and energy storage units 416, each electrically connected to the electrical bus 326. Electrical devices 414 may represent one or more aircraft power loads (e.g., avionics systems, control systems, electric thrusters, etc.), one or more power sources (e.g., auxiliary power units), etc. Energy storage units 416 may be, for example, battery packs for storing electrical energy.

[0119] The electrical bus 326 is further electrically connected to the first motor 410A and the first fuel cell assembly, and electrically connected to the second motor 410B and the second fuel cell assembly. The supervisory controller 412 can be connected to... Figure 5 The controller 240 is constructed in a similar manner, or it can communicate operationally with a first gas turbine engine controller dedicated to the first gas turbine engine 100A and a second gas turbine engine controller dedicated to the second gas turbine engine 100B.

[0120] In this way, it will be understood that the supervisory controller 412 can be configured to receive data from the gas turbine engine sensor 330A of the first gas turbine engine 100A and the gas turbine engine sensor 330B of the second gas turbine engine 100B, and can be further configured to send data (e.g., commands) to various control elements (such as valves) of the first and second gas turbine engines 100A, 100B.

[0121] Furthermore, it will be understood that, for the depicted embodiment, the aircraft 400 includes one or more aircraft sensors 418 configured to sense data indicative of various flight operations of the aircraft 400, including, for example, altitude, ambient temperature, ambient pressure, airflow speed, etc. A supervisory controller 412 is operatively connected to these aircraft sensors 418 to receive data from them.

[0122] In addition to receiving data from sensors 330A, 330B, and 418 and transmitting data to the control element, the supervisory controller 412 is also configured to control the power flow through the electrical bus 326. For example, the supervisory controller 412 may be configured to command and receive desired power extraction from one or more motors (e.g., first motor 410A and second motor 410B), one or more fuel cell assemblies (e.g., first fuel cell assembly and second fuel cell assembly), or both, and to provide all or part of the extracted power to another or both of the one or more motors (e.g., first motor 410A and second motor 410B) and one or more fuel cell assemblies (e.g., first fuel cell assembly and second fuel cell assembly). One or more of these actions may be performed according to the logic outlined below.

[0123] Combustion zone temperature is a significant factor affecting pollutant emissions from gas turbine combustors. Using conventional combustors, the combustion zone temperature range can be as follows: Figure 7 The indicator ranges from 1000K for low-power operation to 2500K for high-power operation.

[0124] Figure 7 It also showed that excessive CO was formed at temperatures below approximately 1670 K, while excessive NO was produced at temperatures above approximately 1900 K. x . CO and NO x The levels are 25 and 15 ppmv below, respectively, within the temperature band between 1670 and 1900 K. The low-emission combustor described below maintains the combustion zone (or multiple combustion zones) within the low-emission temperature band, for example, throughout the entire power range of the engine.

[0125] Still referencing Figure 7 The graph shows the engine's carbon monoxide (CO) and nitrogen oxide (NO) emissions relative to the combustor temperature. x Emissions. Specifically, Figure 7 The graph plots the burner temperature on the x-axis and on the first y-axis (in... Figure 7 The CO content, expressed in parts per million (ppmv), is depicted on the left side of the y-axis, and on the second y-axis (in the left side of the y-axis). Figure 7 The right side of the image depicts NO in ppmv. x Content. CO and NO x Content can refer to CO and NO in burner exhaust. x Content. As used in this article, burner temperature can refer to primary temperature, overall temperature, peak temperature, flame temperature, etc.

[0126] As described in further detail below, the gas turbine engine 100 and / or the integrated fuel cell and combustor assembly 200 are controlled to operate in the combustor 206 at a combustor temperature within a low-emission temperature range 500 (e.g., an emission range). The low-emission temperature range 500 is defined by a lower limit 502 and an upper limit 504. Below the lower limit 502, carbon monoxide (CO) 512 increases beyond a desired threshold. Above the upper limit, nitrogen oxides (NOx) 512 increase. x )514 increased beyond the expected threshold.

[0127] The formation of CO 512 below the lower limit 502 can be due to insufficient combustion rate in burner 206. For example, the air-fuel ratio in burner 206 may be too low or there may not be enough residence time.

[0128] The formation of CO 512 below the lower limit 502 can also be due to insufficient mixing of fuel and air. Here, in some areas of burner 206, the fuel and air mixture may be too weak to support combustion, and in other areas of burner 206, the fuel and air mixture may lead to over-rich combustion, resulting in high local concentrations of CO 512.

[0129] The formation of CO 512 below the lower limit 502 can also be due to product quenching in burner 206 before combustion is complete.

[0130] CO 512 formation is influenced by the stoichiometric ratio (e.g., fuel-air ratio), which is related to the flame temperature. Figure 7 Below the lower limit of 502, CO 512 increases at lower burner temperatures, for example, due to an excessively high equivalence ratio (rich). The increase in CO 512 may be due to the slow oxidation rate associated with low combustion temperatures.

[0131] In the exemplary aspect described, at temperatures above, for example, 1800 Kelvin, the production of CO512 through the chemical dissociation of carbon dioxide (CO2) begins to become significant, which increases the level of CO512.

[0132] NO x The formation of 514 can increase dramatically with combustion temperature; it can increase exponentially with the inlet air temperature of burner 206; it can increase with the square root of the inlet pressure of burner 206; and it can increase with the residence time in the flame zone of burner 206.

[0133] However, it will be understood that, Figure 7 The values ​​provided in the charts are for illustrative purposes only and are intended to illustrate the concepts of this disclosure. CO and NO values ​​for specific engine and burner configurations. xThe actual value of emissions can depend on various additional factors not described here.

[0134] refer to Figure 8 A schematic diagram of an offline tuning aspect of controller 240 is provided. An exemplary offline tuning aspect of controller 240 may include determining multiple sets of fuel cell operating conditions 524. For example, such as... Figure 9 As shown in the table, each set of fuel cell operating conditions 524 corresponds to one of the multiple objective functions 530 and one set of system operating conditions 522.

[0135] For educational purposes, the system described herein includes a gas turbine engine 100, and system operating conditions 522 are described as simulated flight conditions 522. However, in other embodiments (e.g., land-based or water-based vehicles), conditions may include the control inputs, operating conditions, parameters, and performance of the associated system, or conditions of the environment surrounding the system.

[0136] Simulated flight conditions 522 may include altitude, Mach number, environmental conditions (e.g., temperature), conditions or inputs associated with the control or performance of engine 100, and conditions or inputs associated with flight modes (e.g., takeoff, climb, cruise, descent, ground idling, flight idling, etc.). The values ​​of simulated flight conditions 522 may be modeled, pre-measured, and / or determined based on historical flight data and anticipated future flight scenarios.

[0137] Fuel cell operating conditions 524 may include an integrated fuel cell and burner assembly 200 and / or fuel cell stacks 232, 234. Figure 2 The control inputs, operating conditions, parameters, and performance of the fuel cell. As described below, the fuel cell operating conditions 524 may include fuel cell temperature (T_fc), hydrogen conversion rate (CPO), etc. x (H2)), fuel utilization rate (Uf), and power drawn from fuel cell stack 294 (Pelec). In addition, fuel cell operating conditions 524 may include the main fuel flow to burner 206, fuel flow to fuel cell stacks 234A and 234B, etc.

[0138] In some embodiments, fuel cell operating conditions 524 may include other variable aspects of the system that are not directly related to the control, operation, or performance of the integrated fuel cell and burner assembly 200 and / or fuel cell stack 232, 234, but are variable and contribute to the optimal, best, preferred, etc., value of objective function 530. Such fuel cell operating conditions 524 may include variable geometries, such as inlet guide vanes (IGV), variable guide vanes (VGV), and burner equivalence ratio, combinations thereof.

[0139] More generally, in some embodiments, the simulated flight conditions 522 may be known operations or conditions, fixed operations or conditions, selective operations or conditions, measured operations or conditions, etc., and the fuel cell operating conditions 524 may include variable operations or conditions (e.g., those variable operations or conditions associated with the control, operation, or performance of the integrated fuel cell and burner assembly 200 and / or fuel cell stack 232, 234).

[0140] The objective function 530 may include one or more terms representing desired performance and / or emissions. For example, the objective function 530 may include terms that include performance (e.g., thrust demand, power output demand), emissions (e.g., emission regulations), thrust-to-fuel ratio (TSFC), and combinations thereof.

[0141] Thrust-to-fuel ratio (TSFC) is the fuel efficiency of an engine design relative to its thrust output. TSFC can be expressed as fuel consumption (grams per second) per unit of thrust (kilonewtons or kN). TSFC is thrust-specific because it is calculated by dividing fuel consumption by thrust.

[0142] Objective function 530 may include combinations of performance and emissions terms. For example, objective function 530 may include thrust requirements with emissions regulations, thrust and power output requirements with emissions regulations, minimum TSFC with emissions regulations, etc. Weighting factors can be used to determine the priority of each term and the penalties for violating certain terms.

[0143] As an example, objective function 530 may include terms representing minimum TSFC and emission regulation limits. Here, objective function 530 can be expressed as a minimization problem. Objective function 530 can be given as:

[0144] a*TSFC+b*(E–E-Limit)

[0145] TSFC stands for thrust-ratio fuel consumption, and E represents actual emissions (such as CO% and NO). x E-Limit is a prescribed limit (e.g., 118 grams per kilonewton (g / kN) for CO). In this formula, the objective function 530 includes a first term (TSFC) representing performance (e.g., thrust and fuel efficiency) and a second term (E–E-Limit) representing emissions (e.g., the degree of violation of emission regulations).

[0146] The coefficients “a” and “b” can be used to weight the relative costs of the first and second terms. For example, coefficient “a” can be set to 1, and coefficient “b” can be set to a large positive number (e.g., b = 1000). Here, a large value for “b” will result in a high cost penalty for any violation of the E-Limit.

[0147] An engine or system simulator, such as a computational fluid dynamics (CFD) simulator 532 or a test bench, can be used to correlate simulated flight conditions 522 and fuel cell operating conditions 524 with terms of the objective function 530. Simulated flight conditions 522 and fuel cell operating conditions 524 can be correlated with terms of the objective function 530 through a solid oxide fuel cell (SOFC) model, an engine model, constraint control logic, priority logic, combinations thereof, etc. For example, simulator 532 may include the model or logic described in more detail below.

[0148] For example, thrust can be determined from burner power; burner power can be determined from the mass flow rate of the main fuel and the fuel cell, as well as the lower heating value of the main fuel and the fuel cell; and the lower heating value of the fuel cell can be determined based on the electricity drawn from the fuel cell, hydrogen conversion rate, fuel utilization rate, and the temperature of the fuel cell.

[0149] Burner power (Pcomb) can be expressed as:

[0150] Pcomb = W36 * LHV_36 + Wfc * LHV_fc

[0151] Where W36 is the mass flow rate of the main fuel entering the burner through the main inlet (e.g., Figure 5 The mass flow rate of fuel from the third fuel delivery line 150C to the burner, LHV_36 is the lower calorific value of the main fuel, Wfc is the mass flow rate of fuel through the fuel cell stack 294 (further defined below), and LHV_fc is the lower calorific value of the fuel cell stack 294 (further defined below).

[0152] The mass flow rate (Wfc) through the fuel cell stack 294 can be expressed as:

[0153] Wfc = WA_fc + WF_fc

[0154] Where WA_fc is the air flow rate (e.g., from air handling unit 306) and WF_fc is the fuel flow rate (e.g., from fuel handling unit 304).

[0155] The low calorific value (LHV_fc) of a fuel cell can be a function of several fuel cell operating conditions 524, and more specifically, can be expressed as:

[0156] LHV_fc = f(Pelec, CPO) x (H2),Uf,T_fc)

[0157] Pelec draws its power from fuel cells, and CPO x(H2) is the hydrogen conversion rate (e.g., converting fuel into hydrogen-rich fuel via a fuel reformer or fuel processing unit 304), Uf is the fuel utilization rate (e.g., how much hydrogen is consumed in the fuel cell, reflecting the hydrogen reaction rate, such as the current per unit of fuel entering the fuel cell), and T_fc is the temperature of the fuel cell (e.g., the exhaust temperature entering the burner).

[0158] The electricity drawn from a fuel cell can be expressed as:

[0159] Pelec=n*V*I

[0160] Where n is the number of batteries, V is the voltage, and I is the current. The power generated by the fuel cell can be increased by drawing additional current (e.g., charging the batteries or capacitors for later use).

[0161] Because the simulated flight conditions 522 and fuel cell operating conditions 524 are related to terms of the objective function 530 via the simulator 532, the simulator 532 is configured to determine the values ​​of the terms of the objective function 530 based on the values ​​of the flight conditions 522 and the fuel cell operating conditions 524. For example, the simulator 532 determines how the simulated flight conditions 522 and fuel cell operating conditions 524 affect the performance and emissions of the gas turbine engine 100.

[0162] Because various values ​​exist for different simulated flight conditions 522 (e.g., representing various flight modes) and various possible objective functions 530 (e.g., which can be manually selected during engine 100 operation), different sets of values ​​representing multiple fuel cell operating conditions 524 are determined. For example, refer to Figure 9 The table shows "n" sets of flight conditions 522 (e.g., according to various flight modes) and "m" objective functions 530 for each set of flight conditions 522. Therefore, there are defined "m×n" sets of fuel cell operating conditions 524, one set of fuel cell operating conditions for each of the different combinations of the set of flight conditions 522 and objective functions 530.

[0163] To determine the value of each group of fuel cell operating conditions 524, objective function 530 is selected from “m” objective functions 530, and the value of flight condition 522 is selected from “n” groups of flight conditions 522.

[0164] The value of fuel cell operating condition 524 can be repeatedly selected from various groups of values ​​of fuel cell operating condition 524. For example, the various groups of values ​​of fuel cell operating condition 524 cover a range of possible operating conditions for the integrated fuel cell and burner assembly 200 and / or fuel cell stack 232, 234 (and in some cases, also cover operating conditions such as variable geometry and burner equivalence ratio).

[0165] The range of possible operating conditions can be determined based on constraints, including hydrogen conversion (CPO). x The increase in (H2) results in an increase in fuel utilization (Uf) and an increase in fuel cell temperature (T_fc), that is, an increase in the current or power (Pelec) drawn from the fuel cell, an increase in fuel from the fuel cell at the downstream end of the burner 206 relative to the fuel at the upstream end of the burner 206, and a decrease in fuel cell temperature (T_fc).

[0166] Alternatively or additionally, the value of fuel cell operating condition 524 can be determined iteratively.

[0167] like Figure 8 As shown, a first set of values ​​for fuel cell operating conditions 524 and a set of selected values ​​for flight conditions 522 (e.g., selected from a set of flight conditions in “n” sets of flight conditions 522) are combined in simulator 532 to determine the values ​​of terms (and a first overall value) of selected objective function 530 (e.g., selected from one of “m” objective functions 530).

[0168] Feedback loop 534 means repeating this step for multiple sets of values ​​(e.g., second, third, etc.) of fuel cell operating condition 524, thereby resulting in multiple aggregate values ​​of the selected objective function 530 (e.g., second, third, etc.).

[0169] A value of the selected objective function 530 (e.g., a second) is determined as an optimal value, preferred value, best value, etc. For example, it may be expected that the value of the objective function 530 is minimized or maximized depending on the terms of the objective function 530. In some cases, a value of the selected objective function 530 may be a value higher or lower than a threshold of the objective function 530.

[0170] Then, a set of values ​​(e.g., second) of the fuel cell operating conditions 524 corresponding to a selected value (e.g., second) of the selected objective function 530 are stored. Figure 9 In a table (e.g., for online or in-flight use). In a table (e.g., in...) Figure 9 In a row), a set of selected values ​​of fuel cell operating condition 524 are associated with the associated values ​​of the associated objective function 530 selected from “m” objective functions 530 and the associated values ​​of the flight condition 522 selected from “n” sets of flight conditions 522.

[0171] For each combination of one objective function from the "m" objective functions 530 and one set of flight conditions from the "n" sets of flight conditions 522, the above steps are repeated, resulting in "n×m" sets of fuel cell operating conditions 524. Multiple sets of fuel cell operating conditions 524 are stored together with one associated objective function from the "m" objective functions 530 and one set of associated flight conditions from the "n" sets of flight conditions 522. Figure 9 In the table.

[0172] Figure 9 The results table presents a set of optimal, preferred fuel cell operating conditions 524, etc., for different simulated flight conditions 522 and different (e.g., user-constructable or selectable) objective functions 530. Figure 9 In the table, each row represents a set of optimal, preferred, best fuel cell operating conditions 524, etc., for a given set of flight conditions 522 and for a specific objective function 530.

[0173] exist Figure 9 In the table, n1, n2, and n3 can each represent a set of flight conditions 522. For example, n1, n2, and n3 can represent a set of flight conditions associated with flight modes (such as takeoff, cruise, descent, ground idling, flight idling, etc.). For objective function 530, m1, m2, and m3 can each represent objective function 530, such as thrust and emissions, TSFC and emissions, power and emissions, etc. Each column in columns x1-x7 can represent fuel cell operating conditions in a set of fuel cell operating conditions 524. Fuel cell operating conditions 524 can include H2 conversion rate, SOFC exhaust temperature, SOFC fuel utilization rate, SOFC current, late lean injection, and other engine operating conditions, such as variable geometry and combustor equivalence ratio.

[0174] Figure 9 The data in the table can be used to train tuning models for use in real-time control. Tuning models can include neural network models, machine learning models, kernel-based models, fuzzy logic, deep learning models, and combinations thereof.

[0175] As used in this article, the term "machine learning model" refers to one or more mathematical models constructed to find patterns in data and apply the identified patterns to new datasets to form predictions. Different approaches (also known as machine learning categories) are implemented depending on the nature of the problem being solved, as well as the data type and amount of data. Categories of machine learning models include, for example, supervised learning, unsupervised learning, reinforcement learning, deep learning, or combinations thereof.

[0176] Supervised learning utilizes target or outcome variables, such as the dependent variable to be predicted from a given set of predictors (also called independent variables). These sets of variables are used to generate a function that maps labeled inputs to desired outputs. The training process is iterative and continues until the model achieves the desired accuracy on the training data. Machine learning models categorized as supervised learning algorithms and models include, for example, neural networks, regression, decision trees, random forests, k-nearest neighbors (kNN), logistic regression, and others.

[0177] Unlike supervised learning, unsupervised learning is a learning algorithm that does not use labeled data, allowing it to determine structure from the input. In other words, the goal of unsupervised learning is to find hidden patterns in the data through methods such as clustering. Some examples of unsupervised learning include the Apriori algorithm or K-means. Reinforcement learning refers to machine learning models trained to make specific decisions. These models are exposed to an environment where they continuously train themselves using trial and error. Such models learn from past experience and attempt to master the best possible knowledge to make accurate business decisions. Examples of reinforcement learning include the Markov decision process.

[0178] Deep learning is a machine learning method that combines neural networks in successive layers to learn from data iteratively. Deep learning can learn patterns from unstructured data. Deep learning algorithms repeatedly perform tasks and progressively improve results by implementing deep layers of incremental learning. Deep learning can include both supervised and unsupervised learning aspects. Some deep learning machine learning models include, for example, Artificial Neural Networks (ANNs), Convolutional Neural Networks (CNNs), Recurrent Neural Networks (RNNs), Long Short-Term Memory / Gated Recurrent Units (GRUs), Self-Organizing Maps (SOMs), Autoencoders (AEs), and Restricted Boltzmann Machines (RBMs).

[0179] A machine learning model is understood to mean any kind of mathematical model that has at least one non-linear operation (e.g., a non-linear activation layer in the case of a neural network). A machine learning model is trained or optimized by minimizing one or more loss functions separate from the model itself (e.g., minimizing cross-entropy loss or negative log-likelihood). The training or optimization process aims to optimize the model to reproduce known results (low bias) and to enable the model to make accurate predictions from unseen experience (low variance). The model's output can be various things related to the task, such as predicted values, classifications, sequences, etc. In this embodiment, the output can be a gap value and / or a confidence level associated with the predicted gap value.

[0180] However, it should be understood that the use of the neural network model is merely one example of a machine learning model trained to predict a set of fuel cell operating conditions 524 based on flight conditions 522 and an objective function 530. The system includes a neural network model implemented herein as an emissions tuning model 540 to predict fuel cell operating conditions 524 based on real-time flight conditions 542 (which include signals from one or more sensors from the aircraft) and a user-selected objective function 530.

[0181] For example, emission tuning model 540 can use Figure 9 Each row of data in the table is used for training, with simulated flight conditions 522 and objective function 530 as model inputs, and fuel cell operating conditions 524 (including any variable engine operating conditions, such as variable geometry or burner equivalence ratio determined as part of fuel cell operating conditions 524) as output. In training mode, Figure 9 The table provides simulated flight data to inform the emission tuning model 540 of operating conditions and simulated sensor readings.

[0182] The emission tuning model 540 can be trained using supervised or unsupervised methods. Optionally, a feedback loop can be used to tune the weights of the nodes of the emission tuning model 540 to achieve accurate prediction of fuel cell operating conditions 524 under actual operating conditions (e.g., using real or real-time flight conditions 542).

[0183] Now for reference Figure 10 The controller 240 pairs are shown. Figure 9 Real-time applications of tables (e.g., based on) Figure 9 The data in the table is used to train the emission tuning model 540. In real-time flight operations, the controller 240 determines the real-time or actual flight conditions 542 and the user-selected objective function 530. The controller 240 can determine the value of the actual flight conditions 542 (e.g., from sensors).

[0184] The emission tuning model 540 can match the values ​​of the real flight conditions 542 and the selected objective function 530 to a set of fuel cell operating conditions 524. For example, the emission tuning model 540 can be the one described above. Figure 9 The tuning model is trained on the data in the table. Therefore, the emission tuning model 540 can identify a set of fuel cell operating conditions 524, where the values ​​of the real flight conditions 542 are most similar to the values ​​of the simulated flight conditions 522 associated with the identified set of fuel cell operating conditions 524 (e.g., ...). Figure 9 (the same row of the table), and where the user-selected objective function 530 is an objective function 530 associated with the identified set of fuel cell operating conditions 524 (e.g., Figure 9 (The same row in the table).

[0185] The fuel cell operating condition 524 can be the output of the emission tuning model 540, in which the user-selected objective function 530 is input to the tuning model, and the real flight condition 542 replaces the simulated flight condition 522 as the input to the tuning model.

[0186] For example, if the value of the real flight condition 542 matches the value of the first set of simulated flight conditions 522 (e.g., including burner temperatures below the lower limit 502), then the first set of operating conditions 524 associated with the first set of simulated flight conditions 522 is determined.

[0187] If the value of the real flight condition 542 matches the second set of simulated flight conditions 522 (e.g., including burner temperatures above the upper limit 504), then the second set of operating conditions 524 associated with the second set of simulated flight conditions 522 is determined.

[0188] The controller 240 can control the fuel cell operating parameters 544 (e.g., to achieve the fuel cell operating conditions 524) according to the fuel cell operating conditions 524. The fuel cell operating parameters 544 may include parameters of the gas turbine engine 100, the fuel delivery system 146, and the fuel cell and combustor assembly 200.

[0189] For example, fuel cell operating parameters 544 may include operating parameters of air handling unit 306, fuel handling unit 304, power converter 324, valves 235A, 235B, or combinations thereof.

[0190] Additionally or alternatively, fuel cell operating parameters 544 may include air flow rate to air handling unit 306, fuel cell stack 294, or both; fuel flow rate to fuel handling unit 304, fuel cell stack 294, or both; bypass ratio of airflow around air handling unit 306; fuel flow rate to air handling unit 306; temperature, pressure, or both of the airflow supplied to fuel cell assembly 204; composition of the output products of fuel cell assembly 204 supplied to combustion chamber 228; and two or more fuel cell stacks of fuel cell assembly 204 (e.g., first fuel cell stack 232 and second fuel cell stack 234; see also...). Figure 2 The ratio of one or more of these parameters; a combination of two or more of these parameters; etc.

[0191] For example, to achieve a set of fuel cell operating conditions 524, the controller 240 can control the air handling unit 306 to set the fuel cell temperature (T_fc), and can control the reformer or fuel processing unit 304 to set the hydrogen conversion rate (CPO). xThe power converter 324 can be controlled to set the current (I) and fuel utilization rate (Uf) drawn from the fuel cell stack 294. The fuel utilization rate can be represented by the amount of current drawn from the fuel cell stack 294 relative to the amount of fuel entering the fuel cell stack 294. Additionally or alternatively, any other suitable valves, etc., can be controlled to influence the aforementioned fuel cell operating conditions 524.

[0192] Furthermore, controller 240 can control the settings of valves 235A and 235B to control the distribution of fuel flow to fuel cell stacks 234A and 234B and into burner 206. Controller 240 can also additionally control two or more fuel cell stacks relative to each other (e.g., first fuel cell stack 232 and second fuel cell stack 234; see [link]). Figure 2 The parameters of the fuel cell stack 234A and 234B are used as part of the control parameters for the fuel cell operation. As described above, the fuel cell stacks 234A and 234B can be arranged along the length of the combustion chamber 228, so that the controller 240 can control the aspect of the output products injected along the length of the combustion chamber.

[0193] In some embodiments, the value of real flight condition 542 can be used instead of simulated flight condition 522 to improve the tuning model, or the value of real flight condition 542 can be used in addition to simulated flight condition 522 to improve the tuning model. Here, the value of real flight condition 542 can be used instead of... Figure 8 The method uses simulated flight conditions 522 to tune, expand, or update the tuning model and / or Figure 9 The table.

[0194] For example, if a new set of operating conditions 524 and actual flight conditions 542 determines the value of objective function 530, this value of objective function 530 is improved relative to the value of objective function 530 determined by a previous set of operating conditions 524 (e.g., determined by simulated flight conditions 522) and the values ​​of actual flight conditions 542 (e.g., depending on whether the objective function is to be minimized or maximized). Figure 9 The tables and / or tuning models can be updated.

[0195] Tuning can be performed in real time via the aircraft system (e.g., controller 240), remotely in real time via a computing device or controller separate from the aircraft, or offline via the aircraft system or remote computing device, or combinations thereof.

[0196] refer to Figure 11According to the first step 610 of the exemplary method 600, the controller 240 receives data indicating flight conditions 522. For at least some exemplary aspects, the data indicating flight conditions 522 includes data indicating thrust requirements (which may include fan speed requirements) and data indicating the temperature of the burner 206. The data indicating the temperature of the burner 206 may include the current temperature, a predicted temperature in response to changes in burner power, a predicted rate of change or direction of movement of the temperature in response to changes in burner power, a combination thereof, etc.

[0197] According to the second step 620, the controller 240 determines a set of fuel cell operating conditions 524 based on flight conditions 522.

[0198] The controller 240 determines the first set of fuel cell operating conditions 524, wherein flight conditions 522 include the temperature of the burner 206 that is approaching (e.g., direction or rate of change) or has already exceeded the lower limit 502, or the predicted temperature.

[0199] The first set of fuel cell operating conditions 524 may include higher fuel cell temperature (T_fc), higher CPO, etc. x Hydrogen conversion rate (CPO) x (H2)) and high fuel efficiency (Uf).

[0200] Alternatively, controller 240 determines a second set of fuel cell operating conditions 524, wherein flight conditions 522 include the temperature of burner 206 that is approaching (e.g., direction or rate of change) or has already exceeded the upper limit 504, or the predicted temperature.

[0201] The second set of fuel cell operating conditions 524 may include increasing the current (I) drawn from the fuel cell stack 294, reducing the fuel cell exhaust temperature, and injecting combustion gas 266 from the fuel cell stack 294 toward the outlet of the burner 206 (e.g., delayed lean).

[0202] According to the third step 630, in response to determining the first set of fuel cell operating conditions 524, the controller 240 controls the fuel cell operating parameters 544 to achieve the first set of fuel cell operating conditions 524.

[0203] For example, controller 240 controls air handling unit 306 to increase fuel cell temperature (T_fc) and controls fuel handling unit 304 to increase hydrogen conversion rate (CPO). xThe amount of fuel (H2) is increased to improve the fuel utilization rate (Uf) of the fuel cell stack 294, and the valve 151C is controlled to reduce the amount of fuel directly supplied to the burner 206. Since the fuel utilization rate (Uf) reflects the amount of current (I) relative to the amount of fuel entering the fuel cell stack 294, the controller 240 can control the first power converter 324 to increase the current drawn from the fuel cell.

[0204] The first set of fuel cell operating conditions 524 increases the temperature of the burner 206 to shift the temperature of the burner 206 toward or into the temperature range 500, while also contributing to or satisfying another term of the thrust requirement or objective function 530.

[0205] The increased temperature at the air handling unit 306 increases the temperature of the fuel cell exhaust 266 flowing into the combustor 206. The hydrogen-rich fuel from the fuel cell stack 294 increases both the temperature (e.g., the increased equivalence ratio raises the combustion flame temperature, which accelerates the oxidation rate, thus reducing CO emissions) and the efficiency of fuel combustion in the combustor 206. Due to the increased fuel utilization, more hydrogen is consumed in the fuel cell stack 294 (e.g., converted into electricity), and less fuel from the fuel cell stack 294 is emitted into the combustor 206, allowing for increased efficiency.

[0206] The combination of increased exhaust temperature 266 entering combustor 206 from fuel cell stack 294, hydrogen-rich fuel from fuel cell stack 294, and reduced fuel quantity from fuel cell stack 294 increases the temperature of combustor 206 and the fuel combustion efficiency within combustor 206. Combustor 206 burns a smaller amount of hydrogen-rich fuel more efficiently at a higher temperature, thereby increasing the temperature of combustor 206, which further improves the efficiency of combustor 206.

[0207] Alternatively, according to step 640, in response to determining the second set of fuel cell operating conditions 524, controller 240 controls fuel cell operating parameters 544 to achieve the second set of fuel cell operating conditions 524.

[0208] The controller 240 controls the first power converter 324 to increase the current (I) drawn from the fuel cell stack 294, controls the air handling unit 306 to reduce the temperature (T_fc) of the fuel cell, and controls valves 235A and 235B to inject combustion gas 266 toward the outlet of the burner 206.

[0209] The second set of fuel cell operating conditions 524 reduces the temperature of the burner 206 to shift the temperature of the burner 206 toward or into the temperature range 500, while also contributing to or satisfying another of the thrust requirements or objective function 530.

[0210] As the current (I) drawn by the first power converter 324 increases, more hydrogen is consumed in the fuel cell (e.g., converted into electricity), and less fuel is emitted from the fuel cell to the burner. Therefore, the fuel cell supplies less combustible gas to the burner, which acts as an evaporator to reduce NO. x A stream containing relatively low levels of combustible gas can be termed a high-purity stream. High-purity streams quench NO. x Reaction. NO x It decreases exponentially with the increase of water or steam injection or the increase of specific humidity.

[0211] Because the air handling unit 306 lowers the fuel cell temperature (T_fc), NO x Reduce. Because NO x NO increases with air inlet temperature (e.g., fuel cell exhaust temperature), so lowering the fuel cell exhaust temperature will also reduce NO. x .

[0212] Injecting combustion gas 266 (delayed lean) toward the outlet of burner 206 reduces the residence time of combustion gas 266 and thus reduces NO. x .

[0213] This written description uses examples to disclose this disclosure, including best practices, and also enables any person skilled in the art to practice this disclosure, including making and using any device or system and methods of making any combination. The patent scope of this disclosure is defined by the claims, but may include other examples that would occur to a person skilled in the art. Such other examples are intended to fall within the scope of the claims if they include structural elements that are not indistinguishable from the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims.

[0214] Further aspects are provided by the subject matter of the following clauses:

[0215] A gas turbine engine includes: a fuel cell assembly, the fuel cell assembly including a fuel cell stack and defining fuel cell assembly operating parameters; a fuel source; a turbine including a compressor section, a combustor, and a turbine section arranged in a serial flow sequence, the combustor being configured to receive a fuel stream from the fuel source and further configured to receive output products from the fuel cell stack; and a controller including a memory and one or more processors, the memory storing instructions that, when executed by the one or more processors, cause the controller to operate, the operation including: receiving data indicating system operating conditions, the data including data indicating performance requirements and system emission outputs; determining a set of fuel cell operating conditions to shift the system emission outputs into or maintain the system emission outputs within the emission range; and controlling the fuel cell assembly operating parameters according to the determined set of fuel cell operating conditions.

[0216] According to one or more of these provisions, the operation of the gas turbine engine further includes determining the set of fuel cell operating conditions to contribute to the performance requirements.

[0217] According to one or more of these clauses, the gas turbine engine, wherein the data indicating the system emission output includes at least one of the temperature of the burner, the rate of change of the temperature of the burner, and the direction of change of the temperature of the burner.

[0218] According to one or more of these provisions, the gas turbine engine, wherein determining the set of fuel cell operating conditions includes: determining a first set of fuel cell operating conditions in response to determining that the temperature of the burner is approaching or has dropped below the lower limit of the temperature range; or determining a second set of fuel cell operating conditions in response to determining that the temperature of the burner is approaching or has exceeded the upper limit of the temperature range; and wherein controlling the fuel cell assembly operating parameters includes controlling the fuel cell assembly operating parameters according to one of the first set of fuel cell operating conditions or the second set of fuel cell operating conditions.

[0219] According to one or more of these provisions, a gas turbine engine is used, wherein a tuning model determines the set of fuel cell operating conditions, wherein the tuning model is trained based on data including: a first set of flight conditions associated with the first set of fuel cell operating conditions; and a second set of flight conditions associated with the second set of fuel cell operating conditions.

[0220] According to one or more of these provisions, the gas turbine engine, wherein the first set of fuel cell operating conditions corresponds to at least one of the higher temperature, higher hydrogen conversion rate, and higher fuel utilization rate of the fuel cell stack.

[0221] According to one or more of these provisions, the gas turbine engine, wherein the fuel cell assembly includes an air handling unit, a fuel handling unit, and a power converter, wherein controlling the operating parameters of the fuel cell assembly includes at least one of the following: controlling the air handling unit to increase the temperature of the fuel cell stack; controlling the fuel handling unit to increase the hydrogen conversion rate; and controlling the power converter to increase the current drawn from the fuel cell stack.

[0222] According to one or more of these provisions, the gas turbine engine, wherein the first set of fuel cell operating conditions includes a lower amount of fuel directly entering the combustor, wherein the controller is configured to control a valve to reduce the amount of fuel directly supplied to the combustor.

[0223] According to one or more of these provisions, the gas turbine engine, wherein the second set of fuel cell operating conditions corresponds to at least one of increasing the current drawn from the fuel cell stack, decreasing the exhaust temperature from the fuel cell stack, and injecting the output products from the fuel cell stack at the downstream end of the burner.

[0224] According to one or more of these provisions, the gas turbine engine, wherein the fuel cell assembly includes an air handling unit, a fuel handling unit, and a power converter, wherein controlling the operating parameters of the fuel cell assembly includes at least one of the following: controlling the power converter to increase the current drawn from the fuel cell stack; controlling the air handling unit to reduce the exhaust temperature from the fuel cell stack; and controlling the fuel handling unit to inject combustion gases from the fuel cell stack at a downstream end of the burner.

[0225] A method of operating a gas turbine engine, the gas turbine engine including a fuel cell assembly and a turbine, the fuel cell assembly including a fuel cell stack, the turbine including a combustor configured to receive a fuel flow from a fuel supply section of the gas turbine engine and further configured to receive output products from the fuel cell stack, the method comprising: receiving data indicating system operating conditions, the data including data indicating performance requirements and system emission outputs; determining a set of fuel cell operating conditions to shift the system emission outputs into or maintain the system emission outputs within the emission range; and controlling operating parameters of the fuel cell assembly according to the determined set of fuel cell operating conditions.

[0226] The method described according to one or more of these provisions includes determining the set of fuel cell operating conditions to contribute to the performance requirements.

[0227] According to one or more of these provisions, the data indicating the system emission output includes at least one of the burner temperature, the rate of change of the burner temperature, and the direction of change of the burner temperature.

[0228] According to one or more of these provisions, determining the set of fuel cell operating conditions includes: determining a first set of fuel cell operating conditions in response to determining that the temperature of the burner is approaching or has dropped below the lower limit of the temperature range; or determining a second set of fuel cell operating conditions in response to determining that the temperature of the burner is approaching or has exceeded the upper limit of the temperature range.

[0229] The method according to one or more of these provisions, wherein controlling the operating parameters of the fuel cell assembly includes controlling the operating parameters of the fuel cell assembly according to one of the first set of fuel cell operating conditions or the second set of fuel cell operating conditions.

[0230] According to one or more of these provisions, the first set of fuel cell operating conditions corresponds to at least one of higher temperature, higher hydrogen conversion rate, and higher fuel utilization rate of the fuel cell stack.

[0231] The method according to one or more of these provisions, wherein controlling the operating parameters of the fuel cell assembly includes at least one of the following: controlling an air handling unit to increase the temperature of the fuel cell stack; controlling a fuel handling unit to increase hydrogen conversion; and controlling a power converter to increase the current drawn from the fuel cell stack.

[0232] According to one or more of these provisions, the first set of fuel cell operating conditions includes a lower amount of fuel directly entering the burner, wherein the controller is configured to control a valve to reduce the amount of fuel directly supplied to the burner.

[0233] According to one or more of these provisions, the second set of fuel cell operating conditions corresponds to at least one of increasing the current drawn from the fuel cell stack, decreasing the exhaust temperature from the fuel cell stack, and injecting the output products from the fuel cell stack at the downstream end of the burner.

[0234] The method according to one or more of these provisions, wherein controlling the operating parameters of the fuel cell assembly includes at least one of: controlling a power converter to increase the current drawn from the fuel cell stack; controlling an air handling unit to reduce the exhaust temperature from the fuel cell stack; and controlling a fuel handling unit to inject combustion gases from the fuel cell stack at a downstream end of the burner.

Claims

1. A gas turbine engine, characterized in that, include: A fuel cell assembly, the fuel cell assembly including a fuel cell stack and defining fuel cell assembly operating parameters; Fuel source; A turbine comprising a compressor section, a combustor, and a turbine section arranged in a serial flow sequence, the combustor being configured to receive a fuel stream from the fuel source and further configured to receive output products from the fuel cell stack; and A controller, comprising a memory and one or more processors, the memory storing instructions that, when executed by the one or more processors, cause the controller to operate, the operation including: Receive data indicating system operating conditions, including data indicating performance requirements and system emission outputs; Determine a set of fuel cell operating conditions to shift the system emission output into or maintain the system emission output within the emission range; and The operating parameters of the fuel cell assembly are controlled according to a determined set of fuel cell operating conditions. The data output by the indicator system includes at least one of the burner temperature, the rate of change of the burner temperature, and the direction of change of the burner temperature, wherein determining the set of fuel cell operating conditions includes: In response to determining that the temperature of the burner is approaching or has dropped below the lower limit of the temperature range, a first set of fuel cell operating conditions is determined; or In response to determining that the temperature of the burner is approaching or has exceeded the upper limit of the temperature range, a second set of fuel cell operating conditions is determined; and Controlling the operating parameters of the fuel cell assembly includes controlling the operating parameters of the fuel cell assembly according to one of the first set of fuel cell operating conditions or the second set of fuel cell operating conditions.

2. The gas turbine engine according to claim 1, characterized in that, The operation further includes determining the set of fuel cell operating conditions to contribute to the performance requirements.

3. The gas turbine engine according to claim 1, characterized in that, The tuning model determines the set of fuel cell operating conditions, wherein the tuning model is trained based on data, including: The first set of flight conditions associated with the first set of fuel cell operating conditions; and The second set of flight conditions associated with the second set of fuel cell operating conditions.

4. The gas turbine engine according to claim 1, characterized in that, The first set of fuel cell operating conditions corresponds to at least one of the following: higher temperature, higher hydrogen conversion rate, and higher fuel utilization rate of the fuel cell stack.

5. The gas turbine engine according to claim 4, characterized in that, The fuel cell assembly includes an air handling unit, a fuel handling unit, and a power converter, wherein the operating parameters of the fuel cell assembly include at least one of the following: Control the air handling unit to increase the temperature of the fuel cell stack; Control the fuel processing unit to increase hydrogen conversion rate; and Control the power converter to increase the current drawn from the fuel cell stack.

6. The gas turbine engine according to claim 5, characterized in that, The first set of fuel cell operating conditions includes a lower amount of fuel directly entering the burner, wherein the controller is configured to control a valve to reduce the amount of fuel directly supplied to the burner.

7. The gas turbine engine according to claim 1, characterized in that, The second set of fuel cell operating conditions corresponds to at least one of increasing the current drawn from the fuel cell stack, decreasing the exhaust temperature from the fuel cell stack, and injecting the output products from the fuel cell stack at the downstream end of the burner.

8. The gas turbine engine according to claim 7, characterized in that, The fuel cell assembly includes an air handling unit, a fuel handling unit, and a power converter, wherein the operating parameters of the fuel cell assembly include at least one of the following: Control the power converter to increase the current drawn from the fuel cell stack; Control the air handling unit to reduce the exhaust temperature from the fuel cell stack; And control the fuel processing unit to inject combustion gases from the fuel cell stack at the downstream end of the burner.

9. A method of operating a gas turbine engine, the gas turbine engine comprising a fuel cell assembly and a turbine, the fuel cell assembly comprising a fuel cell stack, the turbine comprising a combustor configured to receive a fuel flow from a fuel supply section of the gas turbine engine, and further configured to receive output products from the fuel cell stack, characterized in that, The method includes: Receive data indicating system operating conditions, including data indicating performance requirements and system emission outputs; Determine a set of fuel cell operating conditions to shift the system emission output into or maintain the system emission output within the emission range; and The operating parameters of the fuel cell assembly are controlled according to a determined set of fuel cell operating conditions; wherein determining the set of fuel cell operating conditions includes: In response to determining that the burner temperature is approaching or has fallen below the lower limit of the temperature range, a first set of fuel cell operating conditions is determined; or In response to determining that the temperature of the burner is approaching or has exceeded the upper limit of the temperature range, a second set of fuel cell operating conditions is determined.

10. The method according to claim 9, characterized in that, This includes determining the set of fuel cell operating conditions to contribute to the performance requirements.

11. The method according to claim 9, characterized in that, The data output by the indicator system includes at least one of the following: the temperature of the burner, the rate of change of the burner's temperature, and the direction of change of the burner's temperature.

12. The method according to claim 9, characterized in that, Controlling the operating parameters of the fuel cell assembly includes controlling the operating parameters of the fuel cell assembly according to one of the first set of fuel cell operating conditions or the second set of fuel cell operating conditions.

13. The method according to claim 9, characterized in that, The first set of fuel cell operating conditions corresponds to at least one of the following: higher temperature, higher hydrogen conversion rate, and higher fuel utilization rate of the fuel cell stack.

14. The method according to claim 13, characterized in that, The operating parameters for controlling the fuel cell assembly include at least one of the following: Control the air handling unit to increase the temperature of the fuel cell stack; Control the fuel processing unit to increase hydrogen conversion rate; and Control the power converter to increase the current drawn from the fuel cell stack.

15. The method according to claim 13, characterized in that, The first set of fuel cell operating conditions includes a lower amount of fuel directly entering the burner, wherein the controller is configured to control a valve to reduce the amount of fuel directly supplied to the burner.

16. The method according to claim 9, characterized in that, The second set of fuel cell operating conditions corresponds to at least one of increasing the current drawn from the fuel cell stack, decreasing the exhaust temperature from the fuel cell stack, and injecting the output products from the fuel cell stack at the downstream end of the burner.

17. The method according to claim 16, characterized in that, The operating parameters for controlling the fuel cell assembly include at least one of the following: Control the power converter to increase the current drawn from the fuel cell stack; Control the air handling unit to reduce the exhaust temperature from the fuel cell stack; and The fuel processing unit is controlled to inject combustion gases from the fuel cell stack at the downstream end of the burner.

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