This disclosure relates generally to engine exhaust systems and, more particularly, to exhaust systems having adjustable nozzles and related methods.
An engine exhaust system of a vehicle such as an aircraft includes a nozzle to direct exhaust gases from the engine. The temperature of the exhaust gases influences an infrared signature of the air vehicle that can be detected by infrared sensors.
An example exhaust system includes a nozzle. A portion of the nozzle is moveable from a first position to a second position to change an angle of convergence of the nozzle. The example exhaust system includes an exit area. The portion of the nozzle is at least partially disposed in the exit area. An opening is defined between the exit area and the portion of the nozzle disposed in the exit area. A size of the opening is to change in response to movement of the portion of the nozzle
An example air vehicle includes a manifold to receive exhaust gases from an engine of the air vehicle. The example air vehicle includes a nozzle fluidly coupled to the manifold. A portion of the nozzle is moveable to adjust a size of an outlet of the nozzle. The example apparatus includes an actuator operatively coupled to the portion of the nozzle. The example apparatus includes an exit area. The outlet of the nozzle is disposed in the exit area to direct the exhaust gases into the exit area. The actuator is to cause the portion of the nozzle to move to control an amount of ambient air entering the exit area.
An example apparatus includes a nozzle including an outlet having an adjustable width. The nozzle is to provide a flow path for exhaust gases of an engine. The example apparatus includes an exit area fluidly coupled to the nozzle. The exit area is to expel the exhaust gases. An opening is defined between the exit area and a portion of the nozzle including the outlet. The opening is to receive ambient air to mix with the exhaust gases in the exit area. The example apparatus includes an actuator to control the width of the nozzle. The example apparatus includes at least one memory; machine readable instructions; and processor circuitry to execute the machine readable instructions to cause the actuator to control the width of the outlet of the nozzle to adjust a size of the opening defined between the exit area and the portion of the nozzle including the outlet
In general, the same reference numbers will be used throughout the drawing(s) and accompanying written description to refer to the same or like parts. The figures are not to scale. Instead, the thickness of the layers or regions may be enlarged in the drawings. Although the figures show layers and regions with clean lines and boundaries, some or all of these lines and/or boundaries may be idealized. In reality, the boundaries and/or lines may be unobservable, blended, and/or irregular.
As used herein, connection references (e.g., attached, coupled, connected, and joined) may include intermediate members between the elements referenced by the connection reference and/or relative movement between those elements unless otherwise indicated. As such, connection references do not necessarily infer that two elements are directly connected and/or in fixed relation to each other.
Unless specifically stated otherwise, descriptors such as “first,” “second,” “third,” etc., are used herein without imputing or otherwise indicating any meaning of priority, physical order, arrangement in a list, and/or ordering in any way, but are merely used as labels and/or arbitrary names to distinguish elements for ease of understanding the disclosed examples. In some examples, the descriptor “first” may be used to refer to an element in the detailed description, while the same element may be referred to in a claim with a different descriptor such as “second” or “third.” In such instances, it should be understood that such descriptors are used merely for identifying those elements distinctly that might, for example, otherwise share a same name.
As used herein, the phrase “in communication,” including variations thereof, encompasses direct communication and/or indirect communication through one or more intermediary components, and does not require direct physical (e.g., wired) communication and/or constant communication, but rather additionally includes selective communication at periodic intervals, scheduled intervals, aperiodic intervals, and/or one-time events.
As used herein, “processor circuitry” is defined to include (i) one or more special purpose electrical circuits structured to perform specific operation(s) and including one or more semiconductor-based logic devices (e.g., electrical hardware implemented by one or more transistors), and/or (ii) one or more general purpose semiconductor-based electrical circuits programmable with instructions to perform specific operations and including one or more semiconductor-based logic devices (e.g., electrical hardware implemented by one or more transistors). Examples of processor circuitry include programmable microprocessors, Field Programmable Gate Arrays (FPGAs) that may instantiate instructions, Central Processor Units (CPUs), Graphics Processor Units (GPUs), Digital Signal Processors (DSPs), XPUs, or microcontrollers and integrated circuits such as Application Specific Integrated Circuits (ASICs). For example, an XPU may be implemented by a heterogeneous computing system including multiple types of processor circuitry (e.g., one or more FPGAs, one or more CPUs, one or more GPUs, one or more DSPs, etc., and/or a combination thereof) and application programming interface(s) (API(s)) that may assign computing task(s) to whichever one(s) of the multiple types of processor circuitry is/are best suited to execute the computing task(s).
An engine exhaust system of an air vehicle includes a nozzle to direct exhaust gases from the engine. The temperature of the exhaust gases influences an infrared signature of the air vehicle that can be detected by infrared sensors. When an air vehicle is used for military or defense purposes in a threatening area, detection of the infrared signature due to the emission of exhaust gases and hot metal vehicle components can jeopardize the air vehicle in the case of a manned or unmanned air vehicle and/or personnel in the case of a manned air vehicle.
Some known engine exhaust systems include a nozzle having a static cross-sectional area from which the exhaust gases are emitted. However, such known exhaust nozzles result in trade-offs between engine performance and infrared signature detectability. For instance, a nozzle having a smaller cross-sectional area at, for instance, the outlet can improve the infrared signature of the air vehicle because a smaller amount of exhaust gas is emitted through the nozzle at a given time as compared to a nozzle outlet having a relatively larger cross-sectional area. However, opportunities to increase performance of the engine can be limited by the amount of exhaust gases flowing through nozzles having static or non-adjustable profiles.
Disclosed herein are example exhaust systems including adjustable nozzles to control emission of exhaust gases from an engine in view of an infrared signature of a vehicle including the engine. Example exhaust systems disclosed herein include a variable exhaust area nozzle and an exit area to receive exhaust gases emitted by the nozzle. At least a portion of the nozzle including the outlet is disposed in (e.g., surrounded by) the exit area. Opening(s) are defined between the portion of the nozzle disposed in the exit area and a portion of the exit area. Ambient air enters the exit area via the opening(s) and mixes with the exhaust gases to reduce a temperature of the exhaust gases. In examples in which the vehicle is in, for instance, a threatening environment, an angle of convergence of the nozzle can be adjusted to decrease a size of the portion of the nozzle including the nozzle outlet (i.e., the nozzle outlet is narrowed). As a result, a size of the ambient air openings defined between the exit area and the portion of the nozzle disposed in the exit area increases, which permits more ambient air to enter the exit area. The increased flow of ambient air into the exit area further reduces the temperature of the exhaust gases and surrounding vehicle surface temperatures, which can reduce the infrared signature of the vehicle.
Example exhaust systems disclosed herein can also affect performance of the engine(s) of the vehicle. For instance, when the vehicle is in a non-threatening environment, the angle of convergence of the nozzle can be adjusted to increase a size of the portion of the nozzle including the nozzle outlet (i.e., the nozzle outlet is widened). As a result, an increased amount of exhaust gases can exit the nozzle and be expelled via the exit area. Also, a size of the ambient air opening(s) is decreased due to the increased size of the portion of the nozzle disposed in the exit area. As a result, less ambient air enters the exit area, which provides for less cooling of the exhaust gases. Also, the larger nozzle outlet reduces engine backpressure (e.g., pressure buildup or forces acting on the exhaust gases moving through the nozzle). Thus, increasing the nozzle size can provide for, for example, improved engine fuel burn and power. As such, examples disclosed herein can be used to selectively affect engine performance in view of an infrared signature of the vehicle.
Exhaust gases from the engine(s) 102 flow into the manifold 202, as represented by arrows 208 in
In the example of
In the example of
Also, a size (e.g., a cross-sectional area, a width) of the opening(s) 216 defined between the nozzle 204 and the exit area 206 varies based on the adjustments to the angle of convergence of the portion 215 of the nozzle 204. In particular, when the movable plates(s) 220 of the nozzle 204 are adjusted such that the angle of convergence of the nozzle portion 215 is decreased, the size of the outlet 214 is increased relative to the example shown in
The exhaust system 200 of
In the example of
For example, when the air vehicle 100 is flying in a non-threating environment, the nozzle control circuitry 228 can output instructions (e.g., in response to user input(s)) to cause the plate(s) 220 to move to reduce an angle of convergence of at least the portion 215 of the nozzle 204. Put another way, the plate(s) 220 move to increase a size (e.g., width, cross-sectional area) of the portion 215 of the nozzle 204 and, thus, a size of the outlet 214. The increased size of the outlet 214 of the nozzle 204 permits a larger amount of exhaust gases to be expelled and reduces engine backpressure (e.g., pressure buildup or forces acting on the exhaust gases moving through the nozzle), which can provide for improved power and fuel burn of the engine(s) 102 of the air vehicle 100 during, for instance, long range flights.
As result of the increased size of the portion 215 of the nozzle 204, a size of the opening(s) 216 defined between the nozzle portion 215 and the exit area 206 is reduced. Thus, less ambient air enters into the exit area 206 as compared to when the size (e.g., width, cross-sectional area) of the nozzle portion 215 is narrower. The reduction in ambient air entering the exit area 206 results in less cooling of the exhaust gases flowing into the exit area 206 from the nozzle 204. As such, the infrared signature of air vehicle 100 due to the emission of the exhaust gases may increase (e.g., the air vehicle may be more detectable via infrared sensors).
In examples in which, for instance, the air vehicle 100 is flying through a threatening environment, the nozzle control circuitry 228 can output instructions (e.g., in response to user input(s)) to cause the plate(s) 220 to move to increase the angle of convergence of at least the portion 215 of the nozzle 204. Put another way, the plate(s) 220 move to decrease a size (e.g., width) of the portion 215 of the nozzle 204 and, thus, a size of the outlet 214. Decreasing the size of the nozzle outlet 214 increases a size of the opening(s) 216 defined between the nozzle portion 215 and the exit area 206. As such, an increased amount of ambient air can enter the exit area 206 as compared to when the size of the nozzle portion 215 is decreased (i.e., when the angle of convergence of the nozzle 204 is increased). The ambient air mixes with the exhaust gases in the exit area 206 and reduces a temperature of the exhaust gases. As a result, the infrared signature associated with the air vehicle 100 due to the emission of exhaust gases can be reduced (e.g., the air vehicle may be less detectable via infrared sensors). The decreased size of the outlet 214 of the nozzle 204 permits less exhaust gases to be emitted via the outlet 214 and, thus, can affect performance of the engine 102 by, for example, reducing power generated. Thus, the nozzle control circuitry 228 can selectively adjust the size of the nozzle outlet 214 in view of considerations such as engine performance and detectability of the air vehicle 100 when in threatening areas.
In the example of
The plate 400 is pivotable relative to a remaining portion of the nozzle 300. For instance, the plate 400 is pivotably coupled (e.g., hingedly coupled) to a surface 408 of the nozzle 300 such that the plate 400 moves relative to the surface 408 via a pivot 410 (e.g., shaft, pin). In some examples, the surfaces 406, 408 of the nozzle 300 are integral surfaces. The pivot 410 defines an axis about which the plate 400 moves. The location of the pivot 410 and/or the actuator 404 can differ from the example shown in
As represented by arrows 411, 412 of
The actuator(s) 404 can cause the plate 400 to move in an opposing direction as represented by the arrow 412 of
Although the example nozzles 204, 300 of
A size and/or shape of the nozzle 900 and/or the plates 902, 904 can differ from the example shown in
In some examples, ribs 1008 (e.g., plates, walls) divide or separate an area defining the nozzle 1000 into the respective first, second, and third nozzles 1002, 1004, 1006. The ribs 1008 can provide line-of-sight blockage(s) to the hot engine(s) 102 and exhaust surfaces, in addition to facilitating turning of the flow. The rib(s) 1008 can be separately inserted and coupled to one or more portions (e.g., sidewall(s)) of the nozzle 1000 to define the first, second, and third nozzles 1002, 1004, 1006. In other examples, the rib(s) 1008 are integrally formed in the nozzle 1000. In other examples, one or more of the nozzles 1002, 1004, 1006 is separately formed and coupled to another one of the nozzles 1002, 1004, 1006 via mechanical or chemical fasteners. The example of
In some examples, the first plate 1100 and the second plate 1102 are portions of a single plate that is pivotably coupled to and extends across the first nozzle 1002 and the second nozzle 1004. The third nozzle 1006 of
The third nozzle 1206 of
At block 1404, the example method 1400 includes fluidly coupling an inlet of the nozzle to a manifold of the exhaust system. For example, the inlet 210, 302 of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206 can be fluidly coupled to the manifold 202 to define a flow path for exhaust gases emitted by the engine(s) 102 of the air vehicle 100.
At block 1406, the example method 1400 includes positioning the nozzle relative to the exit area of the exhaust system to at least partially dispose a portion of the nozzle including the outlet in the exit area to define opening(s) between the nozzle and the exit area for ambient air to enter the exit area. For example, the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206 can be positioned relative to the exit area 206 such that the portion 215 of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206 including the outlet 214, 402, 918 is at least partially disposed in (e.g., surrounded by) the exit area 206. The ambient air opening(s) 216 can be defined between an interior surface of the exit area 206 and an exterior surface of the portion 215 of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206 disposed in the exit area 206.
At block 1408, the example method 1400 includes operatively coupling one or more actuators to the plate(s) of the nozzle. For example, the actuator(s) 226, 404, 600, 1104, 1304 can be supported by (e.g., carried by, coupled to) a surface 406 of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206. In some examples, the actuator(s) 226, 404, 600, 1104, 1304 are carried by a frame of the air vehicle 100 and operatively coupled to the plate(s) 220, 400, 902, 904, 1100, 1102, 1300, 1302 via an arm 702.
Although the example method 1400 is described with reference to the flowchart illustrated in
The example nozzle control circuitry 228 of
The flight control interface circuitry 1500 receives instructions from the flight control circuitry 104 of
In response to the instructions from the flight control circuitry 104, the nozzle adjustment management circuitry 1502 determines adjustment(s) to the convergence profile of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206. For example, the nozzle adjustment management circuitry 1502 determines a size (e.g., width, cross-sectional area) of at least a portion 215 of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206 including the outlet 214, 402, 918 to either (a) reduce the infrared signature or (b) increase engine performance. The nozzle adjustment management circuitry 1502 can determines the adjustment(s) to the angle of convergence of the at least the portion 215 of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206 based on, for instance a current position of the movable nozzle plate(s) 220, 400, 902, 904, 1100, 1102, 1300, 1302 and nozzle property reference data 1506. The nozzle property reference data 1506 can include different angles of convergence and/or sizes (e.g., width, cross-sectional area) of at least a portion of a nozzle and corresponding effects on the exhaust gases expelled by the exhaust system 200 (e.g., amount of exhaust gases expelled, temperature of the exhaust gases).
For instance, to increase the amount of power and fuel burn by the engine(s) 102, the nozzle adjustment management circuitry 1502 determines a position to which the plate(s) 220, 400, 902, 904, 1100, 1102, 1300, 1302 should move from the current plate position to increase a size of the nozzle portion 215 including the outlet 214, 402, 918 based on the nozzle property reference data 1506. As a result of increasing the size (e.g., width) of the nozzle portion 215, the angle of convergence of the portion 215 of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206 is reduced (e.g., the nozzle portion 215 is widened). As a result of the decreased angle of convergence of the portion 215 of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206, a size of the ambient air opening(s) 216 is decreased and, thus, less ambient air enters the exit area 206. Also, more exhaust gases are expelled through the larger nozzle outlet 214, 402, 918, which can reduce engine backpressure and increase engine fuel burn and power.
Conversely, to reduce the infrared signature of the air vehicle 100, the nozzle adjustment management circuitry 1502 determines a position to which the plate(s) 220, 400, 902, 904, 1100, 1102, 1300, 1302 should move from the current plate position to decrease a size of the portion 215 of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206 based on the nozzle property reference data 1506. As a result, the angle of convergence of the portion 215 of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206 is increased (e.g., the nozzle portion 215 is narrowed). As a result of the increased angled of convergence of the portion 215 of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206, a size of the ambient air opening(s) 216 is increased and, thus, more ambient air enters the exit area 206 to reduce a temperature of the exhaust gases. Also, the size (e.g., width, cross-sectional area) of the nozzle outlet 214, 402, 918 is reduced, which reduces the amount of exhaust gases expelled.
The nozzle property reference data 1506 can be defined based on user input(s) and stored in a database 1508. In some examples, the nozzle control circuitry 228 includes the database 1508. In some examples, the database 1508 is located external to the nozzle control circuitry 228 in a location accessible to the nozzle control circuitry 228 as shown in
The actuator control circuitry 1504 generates instructions to cause the actuator(s) 226, 404, 600, 1104 to move the plates(s) 220, 400, 902, 904, 1100, 1102, 1300, 1302 to the position determined by the nozzle adjustment management circuitry 1502 to adjust the convergence profile of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206. For example, the actuator control circuitry 1504 generates instructions to cause the actuator(s) 226, 404, 600, 1104 to move the plates(s) 220, 400, 902, 904, 1100, 1102, 1300, 1302 to increase or decrease a size (e.g., width) of at least the portion 215 of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206 including the outlet 214, 402, 918. The actuator control circuitry 1504 transmits the instructions to the actuator(s) 226, 404, 600, 1104.
While an example manner of implementing the nozzle control circuitry 228 of
A flowchart representative of example machine readable instructions, which may be executed to configure processor circuitry to implement the nozzle control circuitry 228 of
The machine readable instructions described herein may be stored in one or more of a compressed format, an encrypted format, a fragmented format, a compiled format, an executable format, a packaged format, etc. Machine readable instructions as described herein may be stored as data or a data structure (e.g., as portions of instructions, code, representations of code, etc.) that may be utilized to create, manufacture, and/or produce machine executable instructions. For example, the machine readable instructions may be fragmented and stored on one or more storage devices and/or computing devices (e.g., servers) located at the same or different locations of a network or collection of networks (e.g., in the cloud, in edge devices, etc.). The machine readable instructions may require one or more of installation, modification, adaptation, updating, combining, supplementing, configuring, decryption, decompression, unpacking, distribution, reassignment, compilation, etc., in order to make them directly readable, interpretable, and/or executable by a computing device and/or other machine. For example, the machine readable instructions may be stored in multiple parts, which are individually compressed, encrypted, and/or stored on separate computing devices, wherein the parts when decrypted, decompressed, and/or combined form a set of machine executable instructions that implement one or more operations that may together form a program such as that described herein.
In another example, the machine readable instructions may be stored in a state in which they may be read by processor circuitry, but require addition of a library (e.g., a dynamic link library (DLL)), a software development kit (SDK), an application programming interface (API), etc., in order to execute the machine readable instructions on a particular computing device or other device. In another example, the machine readable instructions may need to be configured (e.g., settings stored, data input, network addresses recorded, etc.) before the machine readable instructions and/or the corresponding program(s) can be executed in whole or in part. Thus, machine readable media, as used herein, may include machine readable instructions and/or program(s) regardless of the particular format or state of the machine readable instructions and/or program(s) when stored or otherwise at rest or in transit.
The machine readable instructions described herein can be represented by any past, present, or future instruction language, scripting language, programming language, etc. For example, the machine readable instructions may be represented using any of the following languages: C, C++, Java, C #, Perl, Python, JavaScript, HyperText Markup Language (HTML), Structured Query Language (SQL), Swift, etc.
As mentioned above, the example operations of
“Including” and “comprising” (and all forms and tenses thereof) are used herein to be open ended terms. Thus, whenever a claim employs any form of “include” or “comprise” (e.g., comprises, includes, comprising, including, having, etc.) as a preamble or within a claim recitation of any kind, it is to be understood that additional elements, terms, etc., may be present without falling outside the scope of the corresponding claim or recitation. As used herein, when the phrase “at least” is used as the transition term in, for example, a preamble of a claim, it is open-ended in the same manner as the term “comprising” and “including” are open ended. The term “and/or” when used, for example, in a form such as A, B, and/or C refers to any combination or subset of A, B, C such as (1) A alone, (2) B alone, (3) C alone, (4) A with B, (5) A with C, (6) B with C, or (7) A with B and with C. As used herein in the context of describing structures, components, items, objects and/or things, the phrase “at least one of A and B” is intended to refer to implementations including any of (1) at least one A, (2) at least one B, or (3) at least one A and at least one B. Similarly, as used herein in the context of describing structures, components, items, objects and/or things, the phrase “at least one of A or B” is intended to refer to implementations including any of (1) at least one A, (2) at least one B, or (3) at least one A and at least one B. As used herein in the context of describing the performance or execution of processes, instructions, actions, activities and/or steps, the phrase “at least one of A and B” is intended to refer to implementations including any of (1) at least one A, (2) at least one B, or (3) at least one A and at least one B. Similarly, as used herein in the context of describing the performance or execution of processes, instructions, actions, activities and/or steps, the phrase “at least one of A or B” is intended to refer to implementations including any of (1) at least one A, (2) at least one B, or (3) at least one A and at least one B.
As used herein, singular references (e.g., “a,” “an,” “first,” “second,” etc.) do not exclude a plurality. The term “a” or “an” object, as used herein, refers to one or more of that object. The terms “a” (or “an”), “one or more,” and “at least one” are used interchangeably herein. Furthermore, although individually listed, a plurality of means, elements or method actions may be implemented by, e.g., the same entity or object. Additionally, although individual features may be included in different examples or claims, these may possibly be combined, and the inclusion in different examples or claims does not imply that a combination of features is not feasible and/or advantageous.
In examples in which the instructions from the flight control circuitry 104 indicate that the convergence profile of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206 should be adjusted to reduce an infrared signature of the air vehicle 100, control proceeds to block 1604. At block 1604, the nozzle adjustment management circuitry 1502 determines a position to move the plate(s) 220, 400, 902, 904, 1100, 1102, 1300, 1302 to increase the angle of convergence of at least the portion 215 of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206 and, as result, increase a size of the ambient air opening(s) 216 of exit area 206 of the exhaust system 200. The increased size of the ambient air opening(s) 216 permits an increased amount of ambient air to enter the exit area 206 via the ejector effect. The ambient air mixes with the exhaust gases to reduce a temperature of the exhaust gases and, thus, the infrared signature of the air vehicle. Also, the size (e.g., width, cross-sectional area) of the nozzle outlet 214, 402, 918 is reduced, which reduces the amount of exhaust gases expelled. The nozzle adjustment management circuitry 1502 can determine the position to move the plate(s) 220, 400, 902, 904, 1100, 1102, 1300, 1302 based on, for instance, a current position of the plate(s) 220, 400, 902, 904, 1100, 1102, 1300, 1302 and the nozzle property reference data 1506. At block 1606, the actuator control circuitry 1504 causes the actuator(s) 226, 404, 600, 1104, 1304 to move the plate(s) 220, 400, 902, 904, 1100, 1102, 1300, 1302 to the determined position to adjust the angle of convergence.
In examples in which the instructions from the flight control circuitry 104 indicate that the convergence profile of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206 should be adjusted to increase the exhaust gases expelled by the exhaust system 200 to, for instance, adjust engine performance (e.g., increase power, increase fuel burn), control proceeds to block 1608. At block 1608, the nozzle adjustment management circuitry 1502 determines a position to move the plate(s) 220, 400, 902, 904, 1100, 1102, 1300, 1302 to decrease the angle of convergence of at least the portion 215 of the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206 (e.g., widen the nozzle portion 251), In particular, the nozzle adjustment management circuitry 1502 determines a position to which to move the plate(s) 220, 400, 902, 904, 1100, 1102, 1300, 1302 to increase a size of the nozzle outlet 214, 402, 918 to increase an amount of exhaust gases expelled by the exhaust system 200 and reduce engine backpressure. As a result, the size of the ambient air opening(s) 216 of exit area 206 of the exhaust system 200 decreases. The reduced size of the ambient air opening(s) 216 reduces the amount of ambient air entering the exit area 206 via the ejector effect, which provides for less cooling of the exhaust gases. The nozzle adjustment management circuitry 1502 can determine the position to move the plate(s) 220, 400, 902, 904, 1100, 1102, 1300, 1302 based on, for instance, a current position of the plate(s) 220, 400, 902, 904, 1100, 1102, 1300, 1302 and the nozzle property reference data 1506. At block 1610, the actuator control circuitry 1504 causes the actuator(s) 226, 404, 600, 1104, 1304 to move the plate(s) 220, 400, 902, 904, 1100, 1102, 1300, 1302 to the determined position to adjust the angle of convergence.
At block 1612, the flight control interface circuitry 1500 determines if additional instructions have been received to adjust the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206 to affect engine performance or infrared signature of the air vehicle 100. The example instructions 1600 end at block 1614 with continued monitoring for input(s) to adjust the nozzle(s) 204, 300, 900, 1000, 1002, 1004, 1006, 1200, 1202, 1204, 1206.
The processor platform 1700 of the illustrated example includes processor circuitry 1712. The processor circuitry 1712 of the illustrated example is hardware. For example, the processor circuitry 1712 can be implemented by one or more integrated circuits, logic circuits, FPGAs, microprocessors, CPUs, GPUs, DSPs, and/or microcontrollers from any desired family or manufacturer. The processor circuitry 1712 may be implemented by one or more semiconductor based (e.g., silicon based) devices. In this example, the processor circuitry 1712 implements the example flight control interface circuitry 1500, the example nozzle adjustment management circuitry 1502, and the example actuator control circuitry 1504.
The processor circuitry 1712 of the illustrated example includes a local memory 1713 (e.g., a cache, registers, etc.). The processor circuitry 1712 of the illustrated example is in communication with a main memory including a volatile memory 1714 and a non-volatile memory 1716 by a bus 1718. The volatile memory 1714 may be implemented by Synchronous Dynamic Random Access Memory (SDRAM), Dynamic Random Access Memory (DRAM), RAMBUS® Dynamic Random Access Memory (RDRAM®), and/or any other type of RAM device. The non-volatile memory 1716 may be implemented by flash memory and/or any other desired type of memory device. Access to the main memory 1714, 1716 of the illustrated example is controlled by a memory controller 1717.
The processor platform 1700 of the illustrated example also includes interface circuitry 1720. The interface circuitry 1720 may be implemented by hardware in accordance with any type of interface standard, such as an Ethernet interface, a universal serial bus (USB) interface, a Bluetooth® interface, a near field communication (NFC) interface, a Peripheral Component Interconnect (PCI) interface, and/or a Peripheral Component Interconnect Express (PCIe) interface.
In the illustrated example, one or more input devices 1722 are connected to the interface circuitry 1720. The input device(s) 1722 permit(s) a user to enter data and/or commands into the processor circuitry 1712. The input device(s) 1722 can be implemented by, for example, an audio sensor, a microphone, a camera (still or video), a keyboard, a button, a mouse, a touchscreen, a track-pad, a trackball, an isopoint device, and/or a voice recognition system.
One or more output devices 1724 are also connected to the interface circuitry 1720 of the illustrated example. The output device(s) 1724 can be implemented, for example, by display devices (e.g., a light emitting diode (LED), an organic light emitting diode (OLED), a liquid crystal display (LCD), a cathode ray tube (CRT) display, an in-place switching (IPS) display, a touchscreen, etc.), a tactile output device, a printer, and/or speaker. The interface circuitry 1720 of the illustrated example, thus, typically includes a graphics driver card, a graphics driver chip, and/or graphics processor circuitry such as a GPU.
The interface circuitry 1720 of the illustrated example also includes a communication device such as a transmitter, a receiver, a transceiver, a modem, a residential gateway, a wireless access point, and/or a network interface to facilitate exchange of data with external machines (e.g., computing devices of any kind) by a network 1726. The communication can be by, for example, an Ethernet connection, a digital subscriber line (DSL) connection, a telephone line connection, a coaxial cable system, a satellite system, a line-of-site wireless system, a cellular telephone system, an optical connection, etc.
The processor platform 1700 of the illustrated example also includes one or more mass storage devices 1728 to store software and/or data. Examples of such mass storage devices 1728 include magnetic storage devices, optical storage devices, floppy disk drives, HDDs, CDs, Blu-ray disk drives, redundant array of independent disks (RAID) systems, solid state storage devices such as flash memory devices and/or SSDs, and DVD drives.
The machine readable instructions 1732, which may be implemented by the machine readable instructions of
From the foregoing, it will be appreciated that example systems, methods, apparatus, and articles of manufacture have been disclosed that provide for exhaust systems having variable area exhaust nozzles that can be selectively adjusted to affect engine performance and an infrared signature of a vehicle such as an aircraft. Examples disclosed herein include nozzles having moveable portion(s) (e.g., pivotable or slidable plates) to adjust an angle of convergence of the nozzle. In some instances, as a result of movement of the nozzle plate(s), a size (e.g., width, cross-sectional area) of an outlet of the nozzle is increased. The increased size of the nozzle outlet permits an increased an amount of exhaust gases expelled by the exhaust system, reduces engine backpressure, and, thus, increases power and fuel burn from the engine(s) of an air vehicle. In examples in which, for instance, the air vehicle is flying in a threatening area, the angle of convergence of the nozzle can be increased by moving the plate(s) to decrease a size (e.g., width, cross-sectional area) of the outlet. As a result of increasing the angle of convergence of the nozzle, a size of ambient air opening(s) defined between a portion of the nozzle and an exit area of the exhaust system is increased. The increased size of the ambient air opening(s) permits more ambient air to enter the exit area and mix with the exhaust gases to reduce a temperature of the exhaust gases and surrounding surfaces and, thus, the infrared signature of the air vehicle.
Example exhaust systems having adjustable nozzles and related methods are disclosed herein. Further examples and combinations thereof including the following:
Example 1 includes an exhaust system comprising a nozzle, a portion of the nozzle moveable to change an angle of convergence of the nozzle; and an exit area, the portion of the nozzle at least partially disposed in the exit area, an opening defined between the exit area and the portion of the nozzle disposed in the exit area, a size of the opening to change in response to movement of the portion of the nozzle.
Example 2 includes the exhaust system of example 1, wherein the portion of the nozzle at least partially defines an outlet of the nozzle, a size of the outlet to change in response to the movement of the portion of the nozzle.
Example 3 includes the exhaust system of examples 1 or 2, wherein the portion of the nozzle includes a plate pivotably coupled to a surface of the nozzle.
Example 4 includes the exhaust system of any of examples 1-3, further including an actuator operatively coupled to the portion of the nozzle, the actuator carried by the nozzle.
Example 5 includes the exhaust system of any of examples 1-4, further including a manifold, the manifold, the nozzle, and the exit area defining a flow path for exhaust gases from an engine of an air vehicle, ambient air to enter the exit area via the opening.
Example 6 includes the exhaust system of any of examples 1-5, wherein the nozzle is a first nozzle and further including a second nozzle, the second nozzle including a moveable portion.
Example 7 includes the exhaust system of any of examples 1-6, further including a rib disposed between the first nozzle and the second nozzle.
Example 8 includes the exhaust system of any of examples 1-7, further including a slot defined between the first nozzle and the second nozzle.
Example 9 includes an air vehicle comprising a manifold to receive exhaust gases from an engine of the air vehicle; a nozzle fluidly coupled to the manifold, a portion of the nozzle moveable to adjust a size of an outlet of the nozzle; an actuator operatively coupled to the portion of the nozzle; and an exit area, the outlet of the nozzle disposed in the exit area to direct the exhaust gases into the exit area, the actuator to cause the portion of the nozzle to move to control an amount of ambient air entering the exit area.
Example 10 includes the air vehicle of example 9, wherein the actuator is carried by a frame of the air vehicle.
Example 11 includes the air vehicle of examples 9 or 10, wherein the actuator is carried by a surface of the nozzle.
Example 12 includes the air vehicle of any of examples 9-11, wherein the portion of the nozzle includes a plate, the actuator operatively coupled to a first end of the plate.
Example 13 includes the air vehicle of any of examples 9-12, wherein the actuator is a first actuator and further including a second actuator operatively coupled to a second end of the plate.
Example 14 includes the air vehicle of any of examples 9-13, wherein the portion of the nozzle includes a plate, the actuator to cause the plate to pivot from a first position to a second position to one of increase or decrease the size of the outlet.
Example 15 includes the air vehicle of any of examples 9-14, wherein the actuator is to cause the plate to pivot to decrease the size of the outlet, a size of an opening of the exit area to increase in response to the decrease in the size of the outlet, the opening to receive the ambient air.
Example 16 includes an apparatus comprising a nozzle including an outlet having an adjustable width, the nozzle to provide a flow path for exhaust gases of an engine; an exit area fluidly coupled to the nozzle, the exit area to expel the exhaust gases, an opening defined between the exit area and a portion of the nozzle including the outlet, the opening to receive ambient air to mix with the exhaust gases in the exit area; an actuator to control the width of the nozzle; at least one memory; machine readable instructions; and processor circuitry to execute the machine readable instructions to cause the actuator to control the width of the outlet of the nozzle to adjust a size of the opening defined between the exit area and the portion of the nozzle including the outlet.
Example 17 includes the apparatus of example 16, wherein the processor circuitry is to cause the actuator to decrease the width of the outlet to reduce an infrared signature of a vehicle including the engine.
Example 18 includes the apparatus of examples 16 or 17, wherein the processor circuitry is to cause the actuator to increase the width of the outlet to increase an amount of the exhaust gases expelled via the exit area.
Example 19 includes the apparatus of any of examples 16-18, wherein the actuator is to cause a portion of a wall of the nozzle to move to adjust the width of the outlet.
Example 20 includes the apparatus of any of examples 16-19, wherein the actuator is carried by the nozzle.
The following claims are hereby incorporated into this Detailed Description by this reference. Although certain example systems, methods, apparatus, and articles of manufacture have been disclosed herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all systems, methods, apparatus, and articles of manufacture fairly falling within the scope of the claims of this patent.
This invention was made with Government support under W9124P-19-9-001 awarded by the Department of Defense. The government has certain rights in this invention.