Patent Application
20250084796
This disclosure relates generally to an engine assembly for an aircraft propulsion system and, more particularly, to an engine assembly including an intermittent internal combustion engine and a gas turbine engine configured to cooperatively drive a propulsor of the aircraft propulsion system.
A propulsion system for an aircraft may be configured, for example, with an engine assembly including an intermittent internal combustion engine such as a rotary engine. Various configurations of such engine assemblies are known in the art. While these known engine assemblies have various advantages, there is still room in the art for improvement.
It should be understood that any or all of the features or embodiments described herein can be used or combined in any combination with each and every other feature or embodiment described herein unless expressly noted otherwise.
According to an aspect of the present disclosure, an engine assembly for an aircraft propulsion system includes a propulsor, a first gearbox, an engine, a gas turbine engine, and a variable speed drive. The first gearbox includes a first gear assembly coupled with the propulsor. The engine includes an air inlet, an exhaust outlet, and an engine output shaft. The engine output shaft is coupled with the first gear assembly and configured to drive rotation of the propulsor through the first gear assembly. The gas turbine engine includes a first rotational assembly, a compressor section, a turbine section, and a combustor. The first rotational assembly is configured for rotation about a rotational axis. The first rotational assembly includes a bladed compressor rotor for the compressor section, a bladed first turbine rotor for the turbine section, and a first shaft interconnecting the bladed compressor rotor and the bladed first turbine rotor. The compressor section is connected to the air inlet and configured to direct a compressed air to the air inlet. The combustor is connected to the exhaust outlet and configured to receive an exhaust gas from the exhaust outlet. The combustor is configured to direct a combustion gas through the turbine section to drive rotation of the bladed first turbine rotor. The VSD couples the first rotational assembly to the first gear assembly. The VSD is configured to selectively apply a rotational force from the first rotational assembly to the first gear assembly to further drive rotation of the propulsor through the first gear assembly.
In any of the aspects or embodiments described above and herein, the gas turbine engine may further include a second rotational assembly. The second rotational assembly may include a bladed second turbine rotor for the turbine section and a second shaft. The second shaft may interconnect the bladed second turbine rotor and the first gear assembly to further drive rotation of the propulsor through the first gear assembly. The combustor may be configured to direct the combustion gas through the turbine section to drive rotation of the bladed first turbine rotor and the bladed second turbine rotor.
In any of the aspects or embodiments described above and herein, the first shaft and the second shaft may be concentric shafts.
In any of the aspects or embodiments described above and herein, the bladed second turbine rotor may be downstream of the first bladed turbine rotor with respect to the combustion gas.
In any of the aspects or embodiments described above and herein, the VSD may include a first pump, a second pump, and a conduit circuit connected the first pump and the second pump in fluid communication. The first pump may be coupled with the first rotational assembly. The second pump may be coupled with the first gear assembly.
In any of the aspects or embodiments described above and herein, the first pump may be a variable displacement pump and the second pump may be a fixed displacement pump.
In any of the aspects or embodiments described above and herein, the first pump may include a displacement control assembly configured to control a displacement of the first pump. The engine assembly may further include a controller connected in signal communication with the displacement control assembly. The controller may include a processor in communication with a non-transitory memory storing instructions, which instructions when executed by the processor, may cause the processor to control the displacement control assembly to change the displacement of the first pump to apply the rotational force from the first rotational assembly to the first gear assembly.
In any of the aspects or embodiments described above and herein, the first pump may include a displacement control assembly configured to control a displacement of the first pump. The engine assembly may further include a controller connected in signal communication with the displacement control assembly. The controller may include a processor in communication with a non-transitory memory storing instructions, which instructions when executed by the processor, may cause the processor to control the displacement control assembly to change the displacement of the first pump to change a rotation speed of the bladed compressor rotor.
In any of the aspects or embodiments described above and herein, the engine may be an intermittent internal combustion engine.
In any of the aspects or embodiments described above and herein, the engine assembly may further include a second gearbox and a drive shaft. The second gearbox may include a second gear assembly. The drive shaft may couple the first gear assembly with the second gear assembly. The second gear assembly may couple the drive shaft with the propulsor.
In any of the aspects or embodiments described above and herein, the engine assembly may further include an electric control assembly including an electric motor and a battery. The electric motor may be coupled to the second gear assembly. The electric motor may be electrically connected to the battery.
According to another aspect of the present disclosure, an engine assembly for an aircraft propulsion system includes a propulsor, a gearbox, an engine, and a gas turbine engine. The gearbox includes a gear assembly coupled with the propulsor. The engine includes an air inlet, an exhaust outlet, and an engine output shaft. The engine output shaft is coupled with the gear assembly and configured to drive rotation of the propulsor through the gear assembly. The gas turbine engine includes a first rotational assembly, a second rotational assembly, a compressor section, a turbine section, and a combustor. The first rotational assembly and the second rotational assembly are configured for rotation about a rotational axis. The first rotational assembly includes a bladed compressor rotor for the compressor section, a bladed first turbine rotor for the turbine section, and a first shaft interconnecting the bladed compressor rotor and the bladed first turbine rotor. The second rotational assembly includes a bladed second turbine rotor and a second shaft. The first shaft and the second shaft are coupled with the gear assembly to further drive rotation of the propulsor through the gear assembly. The compressor section is connected to the air inlet and configured to direct a compressed air to the air inlet. The combustor is connected to the exhaust outlet and configured to receive an exhaust gas from the exhaust outlet. The combustor is configured to direct a combustion gas through the turbine section to drive rotation of the bladed first turbine rotor.
In any of the aspects or embodiments described above and herein, the bladed second turbine rotor may be downstream of the first bladed turbine rotor with respect to the combustion gas.
In any of the aspects or embodiments described above and herein, the first shaft may be coupled with the gear assembly by a variable speed drive (VSD).
In any of the aspects or embodiments described above and herein, the turbine section may be disposed between the combustor and the compressor section.
In any of the aspects or embodiments described above and herein, the engine assembly may further include a heat exchanger connected in fluid communication between the compressor section and the air inlet. The heat exchanger may be configured to cool the compressed air directed from the compressor section to the air inlet.
According to another aspect of the present disclosure, an engine assembly for an aircraft propulsion system includes a propulsor, a gearbox, an engine, and a gas turbine engine. The gearbox includes a gear assembly coupled with the propulsor. The engine includes an air inlet, an exhaust outlet, and an engine output shaft. The engine output shaft is coupled with the gear assembly and configured to drive rotation of the propulsor through the gear assembly. The gas turbine engine includes a first rotational assembly, a second rotational assembly, a compressor section, a turbine section, and a combustor. The first rotational assembly and the second rotational assembly are configured for rotation about a rotational axis. The first rotational assembly includes a bladed compressor rotor for the compressor section, a bladed first turbine rotor for the turbine section, and a first shaft interconnecting the bladed compressor rotor and the bladed first turbine rotor. The second rotational assembly includes a bladed second turbine rotor and a second shaft. The second shaft is coupled with the gear assembly to further drive rotation of the propulsor through the gear assembly. The compressor section is connected to the air inlet and configured to direct a compressed air to the air inlet. The combustor is connected to the exhaust outlet and configured to receive an exhaust gas from the exhaust outlet. The combustor is configured to direct a combustion gas through the turbine section to drive rotation of the bladed first turbine rotor.
In any of the aspects or embodiments described above and herein, the engine assembly may further include a variable speed drive (VSD) coupling the first rotational assembly to the gear assembly. The VSD may be configured to selectively apply a rotational force from the first rotational assembly to the gear assembly.
In any of the aspects or embodiments described above and herein, the VSD may include a first pump, a second pump, and a conduit circuit connected the first pump and the second pump in fluid communication. The first pump may be coupled with the first rotational assembly. The second pump may be coupled with the gear assembly.
In any of the aspects or embodiments described above and herein, one of the first pump or the second pump may be a variable displacement pump and another of the first pump or the second pump may be a fixed displacement pump.
The present disclosure, and all its aspects, embodiments and advantages associated therewith will become more readily apparent in view of the detailed description provided below, including the accompanying drawings.
The engine 28 of
The gas turbine engine 30 of
The compressor section 42 includes an air inlet 50 and an air outlet 52. The air inlet 50 is connected in fluid communication with an air intake of the propulsion system 20 to receive a flow of ambient air from outside the propulsion system 20. The air outlet 52 is connected in fluid communication with the air inlet 36 to direct compressed air from the compressor 42A to the air inlet 36. The engine assembly 24 may include a heat exchanger 54 (e.g., an intercooler) connected in fluid communication between the air outlet 52 and the air inlet 36 to cool the compressed air directed to the air inlet 36 from the air outlet 52. The heat exchanger 54 may be configured to receive ambient air (e.g., from a propulsion system 20 air scoop or another air source) for cooling the compressed air. The present disclosure, however, is not limited to any particular cooling medium for the heat exchanger 54.
Components of the compressor section 42 and the turbine section 44 form a first rotational assembly 56 (e.g., a high-pressure spool) and a second rotational assembly 58 (e.g., a low-pressure or power spool) mounted for rotation about the rotational axis 48. While the gas turbine engine 30 is described herein as including a two-spool configuration, the present disclosure is also applicable to single-spool gas turbine engine configurations.
The first rotational assembly 56 includes a first shaft 60, a bladed compressor rotor 62 for the compressor 42A, and a bladed first turbine rotor 64 for the high-pressure turbine 44A. The first shaft 60 interconnects the bladed compressor rotor 62 and the bladed turbine rotor 64. The first shaft 60 may extend through the gearbox 32 as shown, for example, in
The second rotational assembly 58 includes a second shaft 66 and a bladed second turbine rotor 68 for the low-pressure turbine 44B. The second shaft 66 interconnects the bladed second turbine rotor 68 with the gearbox 32. The second shaft 66 is coupled with the gearbox 32 to drive, at least in part, rotation of the propulsor 22. The first shaft 60 and the second shaft 66 are concentric and rotate about the rotational axis 48. The present disclosure, however, is not limited to concentric configurations of the first shaft 60 and the second shaft 66 and the first shaft 60 and the second shaft 66 may alternatively be configured for rotation about discrete rotational axes.
The gearbox 32 of
The first pump 82 is coupled with the first shaft 60. For example, the gearbox 32 may include a gear assembly 92 coupling the first pump 82 with the first shaft 60. The first pump 82 may alternatively be coupled with the first shaft 60 by a clutch or another suitable mechanical coupling assembly such that rotation of the first shaft 60 may drive operation of the first pump 82 to pump a fluid through the conduit circuit 86. The first pump 82 of
The second pump 84 is coupled with the drive shaft 72. For example, the second pump 84 may be coupled to the drive shaft 72 by the gear assembly 70. The second pump 84 may be configured as a fixed displacement pump. For example, the second pump 84 may be configured as a fixed displacement piston pump.
Referring again to
To facilitate a reduction in harmful exhaust emissions from the engine 28, the first combustion stage may include a lean fuel-to-air ratio. For example, the compressed air directed to the engine 28 from the compressor 42A, and subsequently mixed with the fuel, may be in excess of a stoichiometric ratio for the fuel-air mixture. As a result, the exhaust gas 96 from the engine 28 may include a substantial quantity of oxygen which was unused in the first combustion stage. Because a significant amount of engine assembly 24 power may be used in the operation of the compressor 42A to compress the air supplied to the engine 28, this unused oxygen in the exhaust gas 96 could, in at least some conventional aircraft propulsion systems, represent wastage of engine assembly 24 power and, therefore, reduced engine assembly 24 efficiency.
The exhaust gas 96 is directed to the combustor 46 to facilitate a second combustion stage for the engine assembly 24 in which a fuel is mixed and burned within the exhaust gas 96 within a combustion chamber of the combustor 46. The fuel directed to the combustor 46 for the second combustion stage may be the same as or different than the fuel used for the first combustion stage. This second combustion stage within the combustor 46 is accomplished with the unused oxygen in the exhaust gas 96 produced in the first combustion stage in the engine 28. As a result, additional engine power for the engine assembly 24 can be extracted by the gas turbine engine 30 using the unused oxygen in the exhaust gas 96.
Combustion gas 98 from the combustor 46 is directed through the high-pressure turbine 44A and the low-pressure turbine 44B. The bladed first turbine rotor 64 and the bladed second turbine rotor 68 rotationally drive the first rotational assembly 56 and the second rotational assembly 58, respectively, in response to the combustion gas 98 flow through the high-pressure turbine 44A and the low-pressure turbine 44B. In particular, the bladed first turbine rotor 64 drives rotation of the bladed compressor rotor 62 with the first shaft 60, thereby facilitating compression of ambient air for the engine 28. The bladed second turbine rotor 68 drives rotation of the propulsor 22 with the second shaft 66 (e.g., through the gear assembly 70, the drive shaft 72, the gear assembly 76, and/or the input shaft 74) in combination with the engine 28 (e.g., the engine output shaft 40). After flowing through the high-pressure turbine 44A and the low-pressure turbine 44B, the combustion gas 98 is exhausted from the propulsion system 20.
During some operational conditions of the engine assembly 24, an output power of the first rotational assembly 56 may be greater than work required by the compressor 42A to compress ambient air for the engine 28. Accordingly, the VSD 34 may selectively apply at least some rotational force from the first shaft 60 to the drive shaft 72 (e.g., with the gear assembly 70). In other words, output power of the first rotational assembly 56 may be variably extracted by the VSD 34 and applied for driving rotation of the propulsor 22 (e.g., in combination with the engine 28 and the second rotational assembly 58), thereby reducing engine 28 loading (e.g., fuel use) while maintaining the desired bladed compressor rotor 62 and propulsor 22 rotation speeds. Briefly referring again to
The controller 26 includes a processor 100 connected in signal communication with memory 102. The processor 100 may include any type of computing device, computational circuit, processor(s), CPU, computer, or the like capable of executing a series of instructions that are stored in the memory 102. Instructions can be directly executable or can be used to develop executable instructions. For example, instructions can be realized as executable or non-executable machine code or as instructions in a high-level language that can be compiled to produce executable or non-executable machine code. Further, instructions also can be realized as or can include data. Computer-executable instructions also can be organized in any format, including routines, subroutines, programs, data structures, objects, modules, applications, applets, functions, etc. The instructions may include an operating system, and/or executable software modules such as program files, system data, buffers, drivers, utilities, and the like. The executable instructions may apply to any functionality described herein to enable the engine assembly 24 and its components to accomplish the same algorithmically and/or by coordination of the engine assembly 24 components. The memory 102 may include a single memory device or a plurality of memory devices (e.g., a computer-readable storage device that can be read, written, or otherwise accessed by a general purpose or special purpose computing device), including any processing electronics and/or processing circuitry capable of executing instructions. The present disclosure is not limited to any particular type of memory device, which may be non-transitory, and may include read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, cache memory, volatile or non-volatile semiconductor memory, optical disk storage, magnetic disk storage, magnetic tape, other magnetic storage devices, or any other medium capable of storing one or more instructions, and/or any device that stores digital information. The memory device(s) may be directly or indirectly coupled to the controller 26. The controller 26 may include, or may be in communication with, an input device that enables a user to enter data and/or instructions, and may include, or be in communication with, an output device configured, for example to display information (e.g., a visual display or a printer), or to transfer data, etc. Communications between the controller 26 and other electrical and/or electronic components (e.g., controllers, sensors, etc.) may be via a hardwire connection or via a wireless connection. A person of skill in the art will recognize that portions of the controller 26 may assume various forms (e.g., digital signal processor, analog device, etc.) capable of performing the functions described herein.
The controller 26 may form or otherwise be part of an electronic engine controller (EEC) for the engine assembly 24. For example, the EEC may control operating parameters of the engine 28 and/or the gas turbine engine 30 such as, but not limited to, fuel flow, stator vane position (e.g., variable compressor inlet guide vane (IGV) position), compressor air bleed valve position, shaft (e.g., first shaft 60 and/or second shaft 66) torque and/or rotation speed, etc. so as to control an engine power or performance of the engine assembly 24. The EEC may modulate fuel flow to the engine 28 and/or the combustor 46 to obtain a desired output power of the engine assembly 24. For example, the EEC may modulate the fuel flow using a closed-loop process in which an output power or other operating parameter of the engine assembly 24 is measured and fuel flow to the engine 28 and/or the gas turbine engine 30 is increased or decreased as a function of the measured output power or operational parameter. In some embodiments, the EEC may be part of a full authority digital engine control (FADEC) system for the propulsion system 20.
The controller 26 may include or otherwise be connected in signal communication with one or more sensors of the engine assembly 24 to measure operational parameters of the engine assembly 24. For example, the controller 26 of
Referring to
Referring to
The electric control assembly 106 of
While the principles of the disclosure have been described above in connection with specific apparatuses and methods, it is to be clearly understood that this description is made only by way of example and not as limitation on the scope of the disclosure. Specific details are given in the above description to provide a thorough understanding of the embodiments. However, it is understood that the embodiments may be practiced without these specific details.
It is noted that the embodiments may be described as a process which is depicted as a flowchart, a flow diagram, a block diagram, etc. Although any one of these structures may describe the operations as a sequential process, many of the operations can be performed in parallel or concurrently. In addition, the order of the operations may be rearranged. A process may correspond to a method, a function, a procedure, a subroutine, a subprogram, etc.
The singular forms “a,” “an,” and “the” refer to one or more than one, unless the context clearly dictates otherwise. For example, the term “comprising a specimen” includes single or plural specimens and is considered equivalent to the phrase “comprising at least one specimen.” The term “or” refers to a single element of stated alternative elements or a combination of two or more elements unless the context clearly indicates otherwise. As used herein, “comprises” means “includes.” Thus, “comprising A or B,” means “including A or B, or A and B,” without excluding additional elements.
It is noted that various connections are set forth between elements in the present description and drawings (the contents of which are included in this disclosure by way of reference). It is noted that these connections are general and, unless specified otherwise, may be direct or indirect and that this specification is not intended to be limiting in this respect. Any reference to attached, fixed, connected, or the like may include permanent, removable, temporary, partial, full and/or any other possible attachment option.
No element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element herein is to be construed under the provisions of 35 U.S.C. 112 (f) unless the element is expressly recited using the phrase “means for.” As used herein, the terms “comprise”, “comprising”, or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
While various inventive aspects, concepts and features of the disclosures may be described and illustrated herein as embodied in combination in the exemplary embodiments, these various aspects, concepts, and features may be used in many alternative embodiments, either individually or in various combinations and sub-combinations thereof. Unless expressly excluded herein all such combinations and sub-combinations are intended to be within the scope of the present application. Still further, while various alternative embodiments as to the various aspects, concepts, and features of the disclosures—such as alternative materials, structures, configurations, methods, devices, and components, and so on—may be described herein, such descriptions are not intended to be a complete or exhaustive list of available alternative embodiments, whether presently known or later developed. Those skilled in the art may readily adopt one or more of the inventive aspects, concepts, or features into additional embodiments and uses within the scope of the present application even if such embodiments are not expressly disclosed herein. For example, in the exemplary embodiments described above within the Detailed Description portion of the present specification, elements may be described as individual units and shown as independent of one another to facilitate the description. In alternative embodiments, such elements may be configured as combined elements.
