Variable bleed valve assembly

Abstract

An example variable bleed valve assembly for a gas turbine engine is disclosed herein. An example apparatus disclosed herein includes a variable bleed valve port extending radially outward from a main flow path of a gas turbine engine; a door positioned at an exit of the variable discharge valve port, the door including a perforation; and a damper coupled to the door, the damper including a resonator adjacent the aperture of the door, the resonator defining an internal volume based on a resonant frequency of the variable discharge valve port.

Description

[0001] Related Applications

[0002] This patent claims priority to Indian Provisional Patent Application No. 202311054511 filed on August 14, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates generally to turbine engines and, more particularly, to variable blowdown valve assemblies. Background Art

[0004] Turbine engines are some of the most widely used power generation technologies, and are commonly used in aircraft and power generation applications. Turbine engines typically include a fan and a core arranged in flow communication with each other. The core of a turbine engine typically includes a compressor section, a combustion section, a turbine section located on the same axis as the compressor section, and an exhaust section in a series flow order. Typically, a casing or outer shell surrounds the core of the turbine engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 is a cross-sectional view of an example gas turbine engine in which examples disclosed herein may be implemented.

[0006] Figure 2 Includes a variable discharge valve assembly Figure 1 A partial cross-sectional side view of a compressor of an example gas turbine engine.

[0007] Figure 3A Yes Figure 2 Side view of a compressor with a variable discharge valve assembly.

[0008] Figure 3B Yes Figure 2 A cross-sectional front view of a compressor with a variable discharge valve assembly.

[0009] Figure 4A is a partial cross-sectional side view of an example first variable drain valve assembly including an example dual damper system in a closed position and in accordance with the teachings disclosed herein.

[0010] Figure 4B is a partial cross-sectional side view of an example first variable discharge valve assembly including a first variable discharge valve assembly in an intermediate position and in accordance with the teachings disclosed herein. Figure 4A Example of a dual damper system.

[0011] Figure 4C is a partial cross-sectional side view of an example first variable drain valve assembly including a first variable drain valve assembly in an open position and in accordance with the teachings disclosed herein. Figure 4AExample of a dual damper system.

[0012] Figure 5 It is used to adjust Figures 4A-4C Block diagram of an example controller for the attenuation range of an example dual damper system.

[0013] Fig. 6A is a partial cross-sectional side view of an example second variable drain valve assembly including an example first damper assembly according to the teachings disclosed herein.

[0014] Figure 6B is a partial cross-sectional side view of an example third variable drain valve assembly including an example second damper assembly in accordance with the teachings disclosed herein.

[0015] Fig. 7A is a partial cross-sectional side view of an example fourth variable drain valve assembly including an example triangular-shaped damper assembly according to the teachings disclosed herein.

[0016] Figure 7B is a partial cross-sectional side view of an example fifth variable drain valve assembly including an example polygonal damper assembly in accordance with the teachings disclosed herein.

[0017] Figure 8 is a cross-sectional front view of an example sixth variable drain valve assembly including an example damper system according to the teachings disclosed herein.

[0018] Fig. 9 is a representation that can be executed by an example programmable circuit to implement Figure 5 Example machine readable instructions and / or flow charts of example operations of an example controller.

[0019] Fig.10 is a block diagram of an example processing platform including programmable circuitry configured to perform Fig. 9 Example machine readable instructions and / or example operations to implement Figure 5 An example controller for

[0020] The drawings are not drawn to scale. On the contrary, the thickness of the layer or region can be enlarged in the drawings. Although the drawings show layers and regions with clear lines and boundaries, some or all of these lines and / or boundaries can be idealized. In fact, the boundaries and / or lines can be unobservable, mixed and / or irregular. Usually, the same reference numerals will be used to represent the same or similar parts throughout the drawings and the accompanying written description. As used in this patent, it is stated that any part (e.g., layer, film, zone, region or plate) indicates that the part referred to is in contact with another part in any way (e.g., positioned at, located at, arranged at or formed at, etc.) on another part, or the part referred to is above another part, with one or more intermediate parts located therebetween. As used herein, unless otherwise specified, a connection reference (e.g., attachment, connection, connection and engagement) may include intermediate members between elements referred to by the connection reference and / or relative motion between those elements. Therefore, a connection reference does not necessarily infer that two elements are directly connected and / or are in a fixed relationship with each other. As used herein, the expression that any part "contacts" another part is defined to mean that there is no intermediate part between the two parts.

[0021] Unless otherwise specifically stated, descriptors such as "first," "second," "third," etc., are used herein without in any way conferring or otherwise indicating any meaning of priority, physical order, arrangement in a list, and / or ordering, but are used merely as labels and / or arbitrary names to distinguish elements for ease of understanding of 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 the claims by a different descriptor (such as "second" or "third"). In such cases, it should be understood that such descriptors are only used to clearly identify those elements that may, for example, share the same name.

[0022] As used throughout the specification and claims, approximate language is used to modify any quantitative expression that can be permissibly varied without resulting in a change in the basic function to which it is related. Therefore, a value modified by one or more terms (such as "about", "approximately", and "substantially") is not limited to the precise value specified. In some examples used herein, the term "substantially" is used to describe a relationship between two parts within three degrees of the relationship (e.g., a substantially collinear relationship is within three degrees of linearity, a substantially perpendicular relationship is within three degrees of perpendicularity, a substantially identical relationship is within three degrees of the same, a substantially flush relationship is within three degrees of flushness, etc.).

[0023] As used herein, the terms "upstream" and "downstream" refer to locations along a fluid flow path relative to a direction of fluid flow from a first location to a second location. For example, with respect to fluid flow, "upstream" refers to a first location from which the fluid is flowing, while "downstream" refers to a second location toward which the fluid is flowing. For example, with respect to a gas turbine engine, a compressor is said to be upstream of the turbine relative to the flow direction of air flowing through the engine.

[0024] Various terms are used herein to describe the orientation of features. Typically, the drawings are annotated with reference to the axial, radial, and circumferential directions of the vehicle associated with features, forces, and moments. Typically, the drawings are annotated with a set of axes including an axial axis A, a radial axis R, and a circumferential axis C.

[0025] In the detailed description below, reference is made to the accompanying drawings that form a part thereof, and specific examples that can be put into practice are shown in the accompanying drawings by way of illustration. These examples are described in sufficient detail to enable those skilled in the art to practice this theme, and it should be understood that other examples may be used. Therefore, the following detailed description is provided to describe exemplary embodiments, and should not be construed as limiting the scope of the subject matter described in this disclosure. Certain features from the different aspects described below may be combined to form additional new aspects of the subject matter discussed below. DETAILED DESCRIPTION

[0026] A turbine engine, also referred to herein as a gas turbine engine, is an internal combustion engine that uses atmospheric air as a motive fluid. In operation, atmospheric air enters the turbine engine via a fan and flows through a compressor section, where one or more compressors gradually compress (e.g., pressurize) the air until it reaches the combustion section. In the combustion section, the pressurized air is combined with fuel and ignited to produce a high-temperature, high-pressure gas flow (e.g., hot combustion gases) before entering the turbine section. The hot combustion gases expand as they flow through the turbine section, causing the rotating blades of one or more turbines to rotate. The rotating blades of the turbine produce a spool work output that powers the corresponding compressor. A spool is a combination of a compressor, a shaft, and a turbine. A turbine engine typically includes multiple spools, such as a high-pressure spool (e.g., an HP compressor, a shaft, and a turbine) and a low-pressure spool (e.g., an LP compressor, a shaft, and a turbine). However, in additional or alternative examples, a turbine engine may include one spool or more than two spools.

[0027] During low-speed operation of a turbine engine (e.g., during startup and / or shutdown), the balance of the engine is adjusted. In many cases, a delay is required to adjust one or more spools (e.g., the time for the rotational speed to adjust to a new balance). However, the compressor cannot stop producing compressed air for fuel combustion during operation. This result may cause the turbine to stop producing power to rotate the compressor, thereby causing the compressor itself to stop compressing air. Therefore, throttling changes may cause compressor instabilities, such as compressor stall and / or compressor surge. Compressor stall is a condition of abnormal airflow caused by aerodynamic stall of the rotor blades within the compressor. Compressor stall causes the air flowing through the compressor to slow down or stagnate. In some cases, when air passes through the various stages of the compressor, the interruption of air flow can cause compressor surge. Compressor surge refers to a stall that causes the airflow through the compressor to be interrupted (e.g., completely interrupted, mostly interrupted, other partially interrupted, etc.).

[0028] Variable discharge valves (VBVs) are typically integrated into the compressor (e.g., at the downstream end of the LP compressor) to improve efficiency and limit possible stalls. The VBV enables the turbine engine to discharge air from the compressor section of the turbine engine during operation. An example VBV assembly or system includes a VBV port (e.g., an opening, a bleed slot, etc.), which includes a VBV cavity extending from the compressor housing and a VBV door opened via actuation. In other words, the VBV is configured as a cavity with a door that opens to provide a discharge flow path to discharge compressed air between the supercharger (e.g., a low-pressure compressor) and the core engine compressor of the gas turbine. For example, the VBV door can be actuated during a speed-speed mismatch between the LP spool and the HP spool. During startup or shutdown, the HP spool can rotate at a lower speed than the LP spool. Opening the VBV port allows the LP spool to maintain its speed while reducing the amount of air flowing through the axial compressor by directing some air flow to the turbine exhaust area. Thus, the VBV gate enables the LP spool (eg, supercharger) to operate at a lower operating line and further away from potential instability or stall conditions.

[0029] In some VBV ports, the VBV door is not flush with the compressor housing, resulting in a discharge cavity that opens to the main flow path within the compressor. When the VBV door is closed, the air of the main flow path flows through the opening of the VBV cavity. This causes the VBV port to acoustically resonate at a fixed frequency or a set of frequencies, similar to blowing air on an empty bottle. This phenomenon is called Helmholtz resonance. More specifically, a shear layer of the main flow path forms across the opening of the VBV cavity. The shear layer has oscillations that couple with the non-flowing air within the VBV cavity. The oscillations can amplify and / or acoustically excite the air in the engine core based on the geometry of the VBV cavity. At certain resonant frequencies, the acoustic excitation causes mechanical vibrations of the rotor system (e.g., rotor blades, rotor disks, rotor blisks (integrated rotor disks and blades), etc.) in the LP compressor. In some cases, the mechanical vibrations propagate and / or intensify upstream along the rotor system toward the initial rotor disk. Such mechanical excitation of the LP compressor can damage the rotor system and / or reduce supercharger performance. For example, one or more rotor blades of an initial rotor stage may break due to excessive mechanical vibrations from acoustic resonances of a closed VBV port (eg, VBV cavity).

[0030] Some current means of reducing the resonant frequency include updates to the electrical engine control (EEC) and / or geometric modifications to the exhaust valve conduit of the VBV assembly. For example, the EEC update may include a process for opening the VBV door in response to detecting a resonant frequency from the VBV assembly. Additionally, geometric modifications to the exhaust valve conduit may include an eccentric profile and / or a reduction in cavity volume to increase frequency margin and / or reduce problematic resonant responses. However, such solutions are associated with relatively high costs, manufacturing resources, and / or decommissioning time. Therefore, a new VBV assembly is required to reduce the resonant frequency of the VBV cavity when the VBV door is closed.

[0031] Some example VBV assemblies disclosed herein include a dual damper system coupled to a VBV door to reduce the acoustic resonant response of the VBV cavity. The dual damper system includes a first resonator and a second resonator positioned on either side of a diaphragm. As used herein, a "resonator" is a device or system that resonates or generates sound waves at a specific frequency to cancel and / or absorb incident acoustic waves of the same or similar frequency. The first resonator and the second resonator are interconnected and can be selectively exposed to the VBV cavity to adjust the resonant frequency of the dual damper system.

[0032] The example VBV assembly disclosed herein suppresses the acoustic response of the air within the VBV cavity to reduce the oscillation of the air within the supercharger. Thus, the disclosed examples enable the manufacture of a VBV assembly that reduces the vibration of the LP compressor or supercharger at various resonant frequencies of the VBV cavity. In other words, the example VBV assembly disclosed herein reduces vibration damage to the rotor system transmitted to the supercharger while improving the aerodynamic performance and / or efficiency of the turbine engine. Thus, the use of the example VBV assembly and the example damper system disclosed herein improves rotor blade durability. In addition, due to the increased rotor durability, the takeoff weight of the aircraft can be reduced by using rotor blades with lower strength and / or material density. The example damper system disclosed herein can be relatively easily coupled to the VBV door of a VBV assembly (e.g., an existing VBV assembly) without the need to replace and / or remanufacture the entire VBV assembly.

[0033] Referring now to the drawings, in which like numerals represent like elements throughout the several views, Figure 1 1 is a schematic cross-sectional view of an example high bypass turbofan type gas turbine engine 110 ("turbofan engine 110"). Although the example shown is a high bypass turbofan engine, the principles of the present disclosure may also be applied to other types of engines, such as low bypass turbofan engines, turbojets, turboprops, etc. Figure 1 As shown, turbofan engine 110 defines a longitudinal or axial centerline axis 112 extending therethrough for reference. Figure 1 Also included are annotated directional diagrams regarding the axial direction A, radial direction R, and circumferential direction C. Generally, as used herein, the axial direction A is a direction extending generally parallel to the centerline axis 112, the radial direction R is a direction extending orthogonally outward from the centerline axis 112, and the circumferential direction C is a direction extending concentrically about the centerline axis 112.

[0034] Typically, the turbofan engine 110 includes a core turbine or gas turbine engine 114 disposed downstream of a fan section 116. The core turbine 114 includes a substantially tubular outer casing 118 defining an annular inlet 120. The outer casing 118 may be formed by a single casing or multiple casings. The outer casing 118 surrounds a compressor section having a supercharger or low-pressure compressor 122 ("LP compressor 122") and a high-pressure compressor 124 ("HP compressor 124"), a combustion section 126, a turbine section having a high-pressure turbine 128 ("HP turbine 128") and a low-pressure turbine 130 ("LP turbine 130"), and an exhaust section 132 in a series flow relationship. A high-pressure spool or shaft 134 ("HP shaft 134") is drivingly coupled to the HP turbine 128 and the HP compressor 124. A low-pressure spool or shaft 136 ("LP shaft 136") is drivingly coupled to the LP turbine 130 and the LP compressor 122. LP shaft 136 may also be coupled to a fan spool or shaft 138 of fan section 116. In some examples, LP shaft 136 is directly coupled to fan shaft 138 (e.g., a direct drive configuration). In an alternative configuration, LP shaft 136 may be coupled to fan shaft 138 via a reduction gear 139 (e.g., an indirect drive or gear drive configuration).

[0035] like Figure 1 As shown, fan section 116 includes a plurality of fan blades 140 coupled to and extending radially outward from fan shaft 138. An annular fan casing or nacelle 142 circumferentially surrounds fan section 116 and / or at least a portion of core turbine 114. Nacelle 142 may be supported relative to core turbine 114 by a plurality of circumferentially spaced outlet guide vanes 144. In addition, a downstream section 146 of nacelle 142 may surround an outer portion of core turbine 114 to define a bypass airflow passage 148 therebetween.

[0036] like Figure 1 As shown, air 150 enters an inlet portion 152 of the turbofan engine 110 during operation of the turbofan engine 110. A first portion 154 of the air 150 flows into the bypass airflow passage 148, while a second portion 156 of the air 150 flows into the inlet 120 of the LP compressor 122. One or more successive stages of LP compressor stator blades 170 and LP compressor rotor blades 172 coupled to the LP shaft 136 progressively compress the second portion 156 of the air 150 that flows through the LP compressor 122 and then is directed to the HP compressor 124. Next, one or more successive stages of HP compressor stator blades 174 and HP compressor rotor blades 176 coupled to the HP shaft 134 further compress the second portion 156 of the air 150 that flows through the HP compressor 124. This provides the compressed air 158 to the combustion section 126 where it is mixed with fuel and combusted to provide combustion gases 160.

[0037] The combustion gases 160 flow through the HP turbine 128, where one or more successive stages of HP turbine stator blades 166 and HP turbine rotor blades 168 coupled to the HP shaft 134 extract a first portion of the kinetic and / or thermal energy therefrom. This energy extraction supports the operation of the HP compressor 124. The combustion gases 160 then flow through the LP turbine 130, where one or more successive stages of LP turbine stator blades 162 and LP turbine rotor blades 164 coupled to the LP shaft 136 extract a second portion of the thermal and / or kinetic energy therefrom. This energy extraction causes the LP shaft 136 to rotate, thereby supporting the operation of the LP compressor 122 and / or the rotation of the fan shaft 138. The combustion gases 160 then exit the core turbine 114 through its exhaust section 132. A turbine frame 161 having a cowling assembly is located between the HP turbine 128 and the LP turbine 130. The turbine frame 161 serves as a support structure, connects the rear bearing of the high pressure shaft to the turbine casing, and forms an aerodynamic transition duct between the HP turbine 128 and the LP turbine 130. The fairing forms a flow path between the high pressure turbine and the low pressure turbine and may be formed using a metal casting (e.g., a nickel-based cast metal alloy, etc.).

[0038] As with the turbofan engine 110, the core turbine 114 is used for similar purposes and is exposed to similar environments in land-based gas turbines, turbojet engines in which the ratio of the first portion 154 of air 150 to the second portion 156 of air 150 is less than that of a turbofan, and unducted fan engines in which the fan section 116 does not have a nacelle 142. In each of the turbofan engine, the turbojet engine, and the unducted engine, a reduction device (e.g., a reduction gear 139) may be included between any shaft and the spool. For example, the reduction gear 139 is provided between the LP shaft 136 and the fan shaft 138 of the fan section 116.

[0039] As mentioned above about Figure 1 As described above, the turbine frame 161 is located between the HP turbine 128 and the LP turbine 130 to connect the rear bearing of the high pressure shaft with the turbine housing and to form an aerodynamic transition duct between the HP turbine 128 and the LP turbine 130. Therefore, air flows through the turbine frame 161 between the HP turbine 128 and the LP turbine 130.

[0040] Figure 2 is a turbine engine (e.g. Figure 1 1 is an illustration of a partial cross-sectional view of an example compressor 200 of a turbofan engine 110 ) including an example LP compressor or supercharger section 202 and an example HP compressor section 204 . Figure 2An example compressor 200 is shown at a transition point 206 between a supercharger section 202 and an HP compressor section 204. The compressor 200 includes an example housing 208. Figure 2 In the example shown, the housing 208 surrounds the supercharger section 202 and the HP compressor section 204. In some examples, the supercharger section 202 and the HP compressor section 204 have different housings 208 connected via a linkage. The housing 208 surrounds the rotor blades 210a and stator vanes 210b of the compressor 200. In operation, the rotor blades 210a rotate, which forces air to flow downstream. The stator vanes 210b redirect and reduce the airflow velocity, which increases the pressure downstream. The housing 208 defines an example main flow path 212 (e.g., a first flow path) for airflow through the compressor 200 (e.g., and the turbofan engine 110).

[0041] like Figure 2 As shown in the example of FIG. 1 , a VBV system or VBV assembly 213 of a turbine engine includes a VBV port 214 (e.g., a passage, opening, duct, etc.) to divert air from a primary flow path 212 and bypass the HP compressor section 204. The VBV port 214 defines an example exhaust flow path 216 (e.g., a secondary flow path) between the supercharger section 202 and the VBV port outlet 218. More specifically, the VBV port 214 includes a front VBV wall 220a and a rear VBV wall 220b extending radially outward between the LP compressor section 202 and the VBV port outlet 218. In some examples, the front VBV wall 220a and the rear VBV wall 220b define an annular geometry of the VBV port 214.

[0042] exist Figure 2 In the example shown, the VBV port 214 includes a VBV door 222 for restricting or allowing airflow through the exhaust flow path 216. The VBV assembly 213 includes a VBV actuation system 224 for actuating the VBV door 222 between an open position 226 and a closed position. For example, the VBV actuation system 224 may include one or more levers (e.g., a bell crank, etc.), linkages, and / or other actuation devices for sliding the VBV door 222 between the open position 226 and the closed position. Thus, the VBV door 222 may be actuated (e.g., movable, translatable, rotatable, etc.) between the open position 226 and the closed position.

[0043] exist Figure 2In the example shown, the VBV door 222 and the VBV actuation system 224 are positioned adjacent to the VBV port outlet 218. The VBV actuation system 224 moves the VBV door 222 (e.g., a barrier door, etc.) to a closed position to cover the VBV port outlet 218. When the VBV door 222 is in the closed position, the exhaust flow path 216 is blocked, and air is relatively stagnant in the VBV port 214 compared to the main flow path 212. In some examples, the VBV door 222, the front VBV wall 220a, and the rear VBV wall 220b of the VBV port 214 define an example VBV cavity 228 when the VBV door 222 is in the closed position. Thus, an air flow shear layer extending across the inlet 230 to the VBV port 214 substantially confines a pocket of air within the VBV cavity 228. The air flow along the main flow path 212 and the shear layer oscillates and causes the air within the VBV cavity 228 to resonate at various frequencies. Such acoustic resonance of the VBV discharge cavity 228 may lead to acoustic excitation and compressor instability in the supercharger section 202. Advantageously, the example VBV assemblies disclosed herein include an acoustic liner to dampen the acoustic resonance of the VBV cavity 228.

[0044] Figure 3A yes Figure 2 2 is a side view of an example compressor 200 including a compressor that may be used in a turbine engine (e.g., Figure 1 and / or Figure 2 A first variable exhaust valve assembly 213 is implemented in a turbofan engine 110). Figure 3B It is taken along line AA Figure 3A A cross-sectional front view of an example compressor 200 is shown. Figure 3A and Figure 3B In the example shown, the VBV door 222 is in the open position 226. Figure 3B Not visible in.

[0045] exist Figure 3A and Figure 3B In the example shown, the supercharger housing 208a surrounds the supercharger section 202 of the compressor 200, and the compressor housing 208b surrounds the HP compressor section 204 of the compressor 200. The supercharger housing 208a is coupled to the compressor housing 208b at the transition point 206. The VBV assembly 213 includes one or more VBV ports 214 integrated into the housing 208 to exhaust air from the main flow path 212. In some examples, the VBV port 214 is formed at the transition point 206 between the supercharger housing 208a and the compressor housing 208b. For example, the supercharger housing 208a may include a front VBV wall 220a ( Figure 2 ), and the compressor housing 208b may include a rear VBV wall 220b ( Figure 2 ). Thus, the VBV port 214 can be generated based on the coupling of the housings 208a, 208b. In some examples, the VBV port 214 is machined into the housing 208. In some examples, an additive manufacturing process integrates the VBV port 214 into the housing 208. Additionally or alternatively, the VBV port 214 can be manufactured separately and coupled (e.g., welded, bolted, etc.) to the housing 208.

[0046] In some examples, the VBV assembly 213 selectively discharges air based on a plurality of VBV ports 214. For example, the housing 208 may include between 8 and 18 VBV ports 214 based on a target discharge flow. In some examples, a corresponding one of the VBV ports 214 includes a door that can be actuatable between an open position and a closed position for adjusting the discharge flow of the VBV assembly 213 based on the target discharge flow and / or flight conditions of the aircraft. In some examples, the VBV assembly 213 includes a plurality of VBV ports 214 disposed about the longitudinal axis of the compressor 200 (e.g., Figure 1 A single unified VBV port 214 extending circumferentially continuously about the axial centerline axis 112. Figure 3A and Figure 3B In the example shown, the VBV assembly 213 includes a plurality of baffles 300 to define the VBV ports 214. That is, the baffles 300 circumferentially separate adjacent ones of the VBV ports 214. The plurality of baffles 300 are circumferentially spaced about the compressor 200 at substantially similar axial and radial locations.

[0047] exist Figure 3B In the example shown, the supercharger housing 208a and the compressor housing 208b include an example outer surface 302 and an example inner surface 304. Figure 3B In the example, Figure 3B Dimension 306 corresponds to the thickness of the casing 208a, 208b and / or the radial length of the VBV port 214. For example, the compressor casing 208b expands radially outward from the inner surface 304 to the outer surface 302 by dimension 306. In some examples, the VBV port 214 extends radially beyond the outer surface 302 and has a radial length greater than dimension 306.

[0048] exist Figure 3B In the example shown, each VBV port 214 includes Figure 2In some examples, the VBV ports 214 are similar in size and the VBV cavities 228 have similar volumes. Alternatively, the VBV ports in the VBV ports 214 may have variable sizes and the VBV cavities in the VBV cavities 228 have different volumes based on the corresponding positions of the diaphragm 300. However, in some examples, the VBV assembly 213 includes a single (e.g., unified, continuous, etc.) VBV port 214 such that the VBV cavity 228 extends circumferentially around the longitudinal axis of the compressor 200.

[0049] Various example VBV components according to the teachings of the present disclosure are described in more detail below. The examples disclosed below are applied to Figure 2 , Figure 3A and Figure 3B An example compressor 200 of an example turbofan engine 110 is shown. Thus, the examples disclosed below include an example housing 208 (e.g., a supercharger housing 208a and a compressor housing 208b) defining a main flow path 212 and an example VBV port 214 defining an example exhaust flow path 216. However, it should be understood that the examples disclosed herein may be implemented in one or more compressors, such as a high-pressure compressor, a low-pressure compressor, etc. In addition, the examples disclosed herein may be implemented on compressors having various configurations, such as including one or more VBV ports, compressor stages, etc. In addition, the examples disclosed herein may be applied to various turbine engines, such as multi-spool turbine engines, turboshaft engines, turbine engines with one compressor section, etc. The examples disclosed below may include a controller for determining to actuate the VBV assembly disclosed herein.

[0050] Figure 2 , Figure 3A and Figure 3B The VBV port 214 of the VBV assembly 213 can resonate at an acoustic frequency based on the volume of the VBV cavity 228. That is, when the VBV door 222 is in the closed position and air flows through the inlet 230 ( Figure 2 )hour, Figure 2 The VBV port 214 resonates at an acoustic frequency, also referred to herein as a resonant frequency. Thus, the VBV assembly 213 can generate air wave oscillations in the supercharger section 202 of the compressor 200 that excite mechanical components of the supercharger section 202 (eg, rotor blades 210a, stator vanes 210b, etc.).

[0051] Figure 4A , Figure 4B and Figure 4C A method according to the teachings disclosed herein includes an example first VBV assembly 400 (eg, a first VBV system) Figure 24 is a partial cross-sectional side view of an example compressor 200. The first VBV assembly 400 includes a dual damper system 402 for reducing acoustic energy generated by the VBV port 214 when air on the main flow path 212 causes the VBV port 214 to resonate. Figure 4A The dual damper system 402 is shown in a closed position 404a, Figure 4B The dual damper system 402 is shown in a neutral position 404b, Figure 4C The dual damper system 402 is shown in an open position 404c. Figures 4A-4C Many components of the first VBV assembly 400 are substantially the same as those above. Figure 2 , Figure 3A and Figure 3B The components described in the VBV assembly 213 are similar or identical. Therefore, for the drawings disclosed herein, the same numerals represent the same elements throughout the drawings.

[0052] exist Figures 4A-4C In the illustrated example, the dual damper system 402 includes a body 406 coupled to a VBV door 408 of a first VBV assembly 400. The body 406 includes a shell 410 and an internal baffle 412. The internal baffle is coupled to the VBV door 408 and an internal surface 414 of the body 406. The internal surface 414 is substantially parallel to the VBV door 408 and radially spaced from the VBV door 408. In addition, the internal baffle 412 extends circumferentially along the VBV door 408. Thus, the shell 410 and the internal baffle 412 define a first damper or first resonator 416 and a second damper or second resonator 418 within the body 406. In addition, the dual damper system 402 includes a first door aperture 420 (e.g., a first through-hole) positioned adjacent to the first resonator 416 and a second door aperture 422 (e.g., a second through-hole) positioned adjacent to the second resonator 418. When the first gate hole 420 is exposed to the VBV cavity 228, the first gate hole 420 allows air pressure oscillations to propagate into the first resonator 416. Similarly, when the second gate hole 422 is exposed to the VBV cavity 228, the second gate hole 422 allows air pressure oscillations to propagate into the second resonator 418.

[0053] exist Figures 4A-4CIn the example shown, the first resonator 416 defines a first internal volume, and the second resonator 418 defines a second internal volume that is different from (e.g., smaller than) the first internal volume. In some examples, the internal volume of the resonator (e.g., the volume of the resonant cavity) defines a resonant frequency that the resonator attenuates (e.g., absorbs). The larger the internal volume of the resonator, the lower the resonant frequency of the resonator, and the lower the resonant frequency that the resonator is able to attenuate or eliminate. Therefore, the dual damper system 402 includes a first resonator 416 that absorbs (e.g., attenuates, reduces, cancels, etc.) a first resonant frequency and a second resonator 418 that absorbs a second resonant frequency that is different from the first resonant frequency. Figures 4A-4C In the example shown, the second resonant frequency is higher than the first resonant frequency based on the first and second interior volumes of the first and second resonators 416, 418. More specifically, when an acoustic wave (e.g., a pressure oscillation) enters the first resonator 416 via the first door hole 420, the wave reflects off the interior surface of the first resonator 416, which causes the first resonator 416 to attenuate the first resonant frequency.

[0054] In some cases, when two adjacent structures resonate at similar frequencies, the amplitude of the resonant acoustic waves is attenuated or eliminated. In addition, the resonant frequency emitted from a cavity (e.g., the VBV cavity 228) can change based on the velocity or flow rate of the flowing air flowing through the open end of the cavity. For example, the VBV cavity 228 can have two "resonance modes." That is, the VBV port 214 can emit two different resonant frequencies based on the velocity of the air flow along the main flow path 212. When the air along the main flow path 212 flows at a first velocity (e.g., 350 miles per hour, etc.), the VBV port 214 can resonate at a first resonant frequency (e.g., 500 Hz, etc.), and when the air flows at a second velocity (e.g., 500 miles per hour, etc.), the VBV port 214 can resonate at a second resonant frequency (e.g., 850 Hz, etc.). The first resonant frequency is lower than the second resonant frequency, and the first velocity is lower than the second velocity. Therefore, in Figures 4A-4C In the example shown, the first resonator 416 can resonate at a first resonant frequency based on the first internal volume to match and attenuate the first resonant frequency of the VBV cavity 228 and / or the VBV port 214. In addition, the second resonator can resonate at a second resonant frequency based on the second internal volume to match and attenuate the second resonant frequency of the VBV cavity 228 and / or the VBV port 214.

[0055] Additionally, the VBV door 408 can slide between a closed position 404a and an open position 404c. Thus, the dual damper system 402 can be actuated using an actuation system (e.g., Figure 2 VBV actuation system 224) or controller 424 in Figure 4A The closed position 404a, Figure 4B The middle position 404b and Figure 4C In the closed position 404a, the rear VBV wall 220b blocks the second door hole 422. Therefore, when the dual damper system 402 is in the closed position 404a, acoustic waves can enter the first resonator 416 via the first door hole 420. In other words, when the dual damper system 402 is in the closed position 404a, the acoustic waves can enter the first resonator 416 via the first door hole 420. Figure 4A When the closed position 404a is selected, the first resonator 416 can suppress the first resonant frequency or lower resonant mode (e.g., 600 Hz, etc.) of the VBV port 214. In addition, the controller 424 can move the dual damper system 402 to the intermediate position 404b to allow pressure-driven acoustic waves to enter the second resonator 418 through the second door aperture 422. The intermediate position 404b allows the second door aperture 422 to be opened / exposed while the VBV door 408 is still able to block / obstruct Figure 4C VBV port outlet 218. Therefore, when the dual damper system 402 is in Figure 4B When the dual damper system is in the intermediate position 404b, the second resonator 418 can suppress a second resonant frequency (eg, a higher frequency) of the VBV port 214. In some examples, the front VBV wall 220a blocks the first door aperture 420 when the dual damper system is in the intermediate position 404b.

[0056] exist Figures 4A-4C In the example shown, the inner baffle 412 includes baffle holes 426 to allow air pressure waves to flow between the first resonator 416 and the second resonator 418. In some examples, when the dual damper system 402 is in Figure 4A When in the closed position 404a, the baffle hole 426 allows reflected acoustic waves to enter the second resonator 418 from the first resonator 416. The reflected waves that enter the second resonator 418 via the baffle hole 426 continue to reflect within the second resonator 418, which causes additional acoustic damping. Therefore, when in the closed position 404a, the dual damper system 402 operates as a single damper in the damper. In other words, the first resonator 416 and the second resonator 418 can operate as two interconnected dampers in series, so that the second resonator can still provide attenuation benefits while the second door hole 422 is blocked. In addition, when the dual damper system 402 is in the closed position 404a, the second ... Figure 4B When in the intermediate position 404b, the baffle hole 426 enables the reflected acoustic waves from the second resonator 418 to be further reflected with the first resonator 416, which also causes additional acoustic damping. Therefore, when in the intermediate position 404b, the dual damper system 402 operates as two interconnected dampers.

[0057] exist Figures 4A-4CIn the example shown, the interior surface 414 of the body 406 is non-uniform (e.g., corrugated, ridged, jagged, etc.) to increase the damping characteristics of the first resonator 416 and the second resonator 418. More specifically, the ridged surface profile of the interior surface 414 causes the acoustic waves to be reflected in various and / or random directions within the first resonator 416 and the second resonator 418. As a result, more interactions occur between the reflected waves entering through the first door aperture 420 and / or the second door aperture 422 and the incident acoustic waves, which further suppresses the resonant waves entering the first resonator 416 and the second resonator 418. Additionally or alternatively, the interior surface 414 or one or more portions of the interior surface 414 can be flat and / or smoothly corrugated (e.g., curved, wavy, hemispherical, etc.). In some examples, the dual damper system 402 includes an acoustic pad (e.g., a quarter wave plate) coupled to the interior surface 414 to provide further acoustic damping. For example, the acoustic pad coupled to the interior surface 414 may correspond to the following combination Fig. 6A and / or Figure 6B Acoustic pads described.

[0058] exist Figures 4A-4C In the example shown, the dual damper system 402 includes a position sensor 428 to detect the position of the VBV door 408, such as the closed position 404a, the intermediate position 404b, the open position 404c, or another intermediate position. For example, the position sensor 428 can be a capacitive displacement sensor, a Hall effect sensor, a linear variable differential transformer (LVDT), or another type of sensor that can measure the position displacement of the VBV port 214. The controller 424 can obtain position data (e.g., displacement measurements) from the position sensor 428 based on a signal from the acoustic sensor 430 and / or on a continuous or periodic basis (e.g., every second, every minute, etc.).

[0059] exist Figures 4A-4C In the example shown, the dual damper system 402 includes an acoustic sensor 430 to detect an acoustic frequency of the VBV port 214, such as a first resonant frequency corresponding to a first resonant mode of the VBV port 214 and / or a second resonant frequency corresponding to a second resonant mode of the VBV port 214. The acoustic sensor 430 may be a pressure transducer capable of detecting low-frequency air pressure waves impinging on a cavity wall (e.g., the front VBV wall 220a, the rear VBV wall 220b, etc.) and / or another type of acoustic sensor capable of detecting and / or measuring an acoustic resonant frequency.

[0060] Figures 4A-4CThe controller 424 of the illustrated example may obtain position data from the position sensor 428 and frequency data from the acoustic sensor 430 to determine how to actuate the dual damper system 402. For example, when the acoustic sensor 430 detects that the VBV port 214 is resonating at a second resonant frequency (e.g., a higher resonant mode), the controller 424 may actuate or move the VBV door 408 to a position where the VBV port 214 is resonating at a second resonant frequency (e.g., a higher resonant mode). Figure 4B In another example, when the acoustic sensor 430 detects that the VBV port 214 is resonating at a first resonant frequency (e.g., a lower resonant mode), the controller 424 can actuate or move the VBV door 408 to the closed position 404a. In some examples, when the resonant frequency of the VBV port 214 meets a threshold (e.g., 600 Hz, etc.), the controller 424 moves the VBV door 408 to the intermediate position 404b. Similarly, when the resonant frequency of the VBV port 214 does not meet the threshold, the controller 424 can move the VBV door 408 to the closed position 404a. Figure 5 A further description of controller 424 is provided.

[0061] Additionally or alternatively, the controller 424 may actuate the dual damper system 402 based on flight conditions of the aircraft and / or gas turbine engine. The resonant frequency of the VBV port 214 is based on the geometry of the VBV cavity and the air velocity along the main flow path 212. Thus, the controller 424 may determine the resonant frequency that the VBV port 214 may produce based on the flight conditions of the aircraft (e.g., cruising speed, takeoff speed, landing speed, etc.). For example, the controller 424 may obtain the air speed of the aircraft from an avionics system and / or an air speed indicator, and when the air speed meets a speed threshold (e.g., 700 mph, etc.), the controller 424 may move the dual damper system 402 to the intermediate position 404 b.

[0062] Figure 5 is a block diagram of a controller 424 for adjusting the range of resonant frequencies that the dual damper system 402 is able to attenuate. Thus, the controller 424 can ensure that Figures 4A-4C The position of the VBV door 408 enables the dual damper system 402 to attenuate or suppress the resonant frequency of the VBV port 214 based on the resonant frequency of the VBV port 214 and / or the operating speed or flight conditions of the aircraft. More specifically, the controller 424 can adjust the position of the dual damper system 402 to selectively block / obstruct and / or expose / open the first door aperture 420 and / or the second door aperture 422, thereby activating the first resonator 416 and / or the second resonator 418.

[0063] Figure 5The controller 424 of the illustrated example includes an example interface circuit 502 , an example frequency determination circuit 504 , an example position determination circuit 506 , an example gate controller circuit 508 , and an example data storage 510 . Figure 4A , Figure 4B , Figure 4C and Figure 5 The controller 424 may be instantiated (e.g., create an instance that is generated, implemented, performed, etc., for any length of time) by a programmable circuit such as a central processing unit that executes instructions. Additionally or alternatively, Figure 4A , Figure 4B , Figure 4C and Figure 5 The controller 424 may be instantiated (e.g., created to be generated, implemented, performed, etc., for any length of time) by an application specific integrated circuit (ASIC) or a field programmable gate array (FPGA) that is configured to perform operations corresponding to the instructions. It should be understood that Figure 5 Some or all of the circuits of may thus be instantiated at the same or different times. For example, some or all of the circuits may be instantiated in one or more threads that execute in parallel on the hardware and / or in serial on the hardware. Furthermore, in some examples, Figure 5 Some or all of the circuitry may be implemented by a microprocessor circuit that executes instructions to implement one or more virtual machines and / or containers.

[0064] Controller 424 includes interface circuit 502 for synchronizing operations between input / output devices and circuits (e.g., processor circuits) of controller 424. In some examples, interface circuit 502 is configured to execute interface instructions and / or to perform operations such as by Fig. 9 In some examples, the operations represented by the flowcharts are instantiated by programmable circuits. Figures 4A-4C The aircraft of the dual damper system 402 includes an input device (e.g., a switch, a dial, a button, a knob, a keyboard, a touch pad, etc.) in the cockpit or another control center onboard. Using such an input device, the operator can cause the dual damper system 402 to Figure 4A The closed position 404a, Figure 4B The middle position 404b and Figure 4C404c. For example, when the aircraft has landed and / or completed flight operations, the pilot can provide input to the controller 424 to move the dual damper system 402 to the closed position 404a. In addition, the interface circuit 502 allows the controller 424 to communicate with the position sensor 428 and the acoustic sensor 430. For example, the interface circuit 502 can obtain position data from the position sensor 428 and obtain frequency data from the acoustic sensor 430. Additionally or alternatively, the interface circuit 502 can enable the controller to obtain air speed data from the control system of the aircraft (e.g., an air speed indicator, an avionics system, etc.).

[0065] The controller 424 includes a frequency determination circuit 504 for detecting Figures 4A-4C Additionally or alternatively, the controller 424 includes a frequency determination circuit 504 for determining whether the resonant frequency of the VBV port 214 meets a threshold. More specifically, the frequency determination circuit 504 obtains data (e.g., frequency data) from the acoustic sensor 430 and / or the interface circuit 502, and detects Figures 4A-4C The resonant frequency within the VBV cavity 228 is then determined by the frequency determination circuit 504 to determine whether the resonant frequency meets (e.g., is greater than or equal to) a threshold. In some examples, the frequency determination circuit 504 is configured to execute frequency determination instructions and / or to perform operations such as by Fig. 9 The frequency determination circuit 504 can be used as a closed-loop controller that takes input feedback data (e.g., resonant frequency) from the acoustic sensor 430 and sends output data (e.g., the position of the VBV gate 408) to the gate controller circuit 508 of the controller 424.

[0066] Figure 5 The controller 424 of the example includes a position determination circuit 506 for determining the position of the Figures 4A-4C The position of the VBV door 408 is determined based on data from the position sensor 428 and / or an input device in the cockpit of the aircraft. More specifically, the position determination circuit 506 obtains data (e.g., position displacement measurements) from the position sensor 428 and detects the position of the dual damper system 402 based on the data. In some examples, the position determination circuit 506 is configured to execute position determination instructions and / or to perform operations such as Fig. 9 The position determination circuit 506 can be used as a closed-loop controller that takes input feedback data (e.g., acoustic measurements, frequency measurements, etc.) from the frequency determination circuit 504 and sends output data (e.g., the target position of the VBV gate 408) to the gate controller circuit 508 of the controller 424.

[0067] Figure 5 The controller 424 of the example includes a gate controller circuit 508 for adjusting Figures 4A-4C The gate controller circuit 508 may further include a gate controller circuit 508 that controls the position of the VBV door 408 and the dual damper system 402. More specifically, the gate controller circuit 508 receives a signal indicating a target VBV gate position and / or a target resonant frequency of the VBV port 214. The gate controller circuit 508 may then move the VBV door 408 to a position (e.g., a closed position 404a, an intermediate position 404b, an open position 404c, etc.) to block and / or expose the first gate aperture 420 and / or the second gate aperture 422 based on the resonant frequency that the dual damper system 402 will attenuate.

[0068] In some examples, gate controller circuit 508 is configured to execute gate controller instructions and / or to perform operations such as Fig. 9 In some examples, the door controller circuit 508 is configured as a closed-loop controller that receives position feedback from the position sensor 428 and / or the interface circuit 502 and continues to send output signals that cause actuation of the VBV door 408 until the door controller circuit 508 determines that the dual damper system 402 is in the target position.

[0069] Controller 424 includes data storage 510 for storing data (e.g., position measurements, frequency measurements, air speed measurements, thresholds, etc.) or any information associated with interface circuit 502, frequency determination circuit 504, position determination circuit 506, and / or gate controller circuit 508. Figure 5 The example data store 510 of the illustrated example may be implemented by any memory, storage device, and / or storage disk for storing data, such as flash memory, magnetic media, optical media, etc. In addition, the data stored in the example data store 510 may be in any data format, such as binary data, comma-delimited data, tab-delimited data, structured query language (SQL) structures, image data, etc.

[0070] although Figures 4A-4C An example implementation of the controller 424 is Figure 5 However, Figure 5 One or more elements, processes and / or devices shown in the drawings may be combined, divided, rearranged, omitted, eliminated and / or implemented in another manner. Figures 4A-4CThe example interface circuit 502, the example frequency determination circuit 504, the example position determination circuit 506, the example gate controller circuit 508, and / or more generally, the example controller 424 may be implemented by hardware alone, or by a combination of hardware and software and / or firmware. Thus, for example, any of the example interface circuit 502, the example frequency determination circuit 504, the example position determination circuit 506, the example gate controller circuit 508, and / or more generally, the example controller 424 may be implemented by a programmable circuit, an analog circuit, a digital circuit, a logic circuit, a programmable processor, a programmable microcontroller, a graphics processing unit (GPU), a digital signal processor (DSP), an ASIC, a programmable logic device (PLD), and / or a field programmable logic device (FPLD) (e.g., an FPGA). In addition, Figures 4A-4C An example controller 424 may include Figure 5 In addition to or in lieu of those shown Figure 5 One or more of those shown, processes and / or means, and / or may include more than one of any or all of the shown elements, processes and means.

[0071] Fig. 6A An example second VBV assembly 600a (eg, a second VBV system) according to the teachings disclosed herein Figure 2 FIG. 2 is a partial cross-sectional side view of an example compressor 200 . Figure 6B A method according to the teachings disclosed herein includes an example third VBV assembly 600b (eg, a third VBV system) Figure 2 FIG. 2 is a partial cross-sectional side view of an example compressor 200 . Fig. 6A An example of a second VBV assembly 600a and Figure 6B Many components of the third VBV assembly 600b are basically combined with the above Figure 2 , Figure 3A and Figure 3B The components described in the VBV assembly 213 are similar or identical. Therefore, for the drawings disclosed herein, the same numerals represent the same elements throughout the drawings.

[0072] The second VBV assembly 600a includes a first damper assembly 602a for reducing acoustic energy generated by the VBV port 214 when air on the main flow path 212 causes the VBV port 214 to resonate. Similarly, the third VBV assembly 600b includes a second damper assembly 602b for reducing acoustic energy resonating from the VBV port 214. The first damper assembly 602a is similar to the second damper assembly 602b. Therefore, unless otherwise stated, the description provided in conjunction with the first damper assembly 602a can also be applied to the second damper assembly 602b.

[0073] The first damper assembly 602a includes a resonator or body 604 coupled to a door 606. The body 604 includes a front wall 608, a rear wall 610, and an outer wall 612. The door 606 includes a plurality of door holes 614 adjacent to the body 604. The door holes 614 allow air pressure oscillations to enter the body 604 and reflect off the interior surface of the body 604 to reduce the energy of the incoming sound waves. In some examples, the resonant frequency that the first damper assembly 602a is able to attenuate is based on the interior volume of the first damper assembly 602a and the number and / or size of the door holes 614.

[0074] also, Fig. 6A The first damper assembly 602a includes a first acoustic pad 616a, and Figure 6B The second damper assembly 602b includes a second acoustic pad 616b to further absorb the sound waves resonating from the VBV port 214. The first acoustic pad 616a is disposed within the body 604 of the first damper assembly 602a. The second acoustic pad 616b is disposed within the body 604 of the second damper assembly 602b. Fig. 6A In the example shown, the first acoustic pad 616a includes a ridged surface profile. Figure 6B In the example shown, the second acoustic pad 616b includes a triangular surface profile. In some examples, the first acoustic pad 616a and the second acoustic pad 616b are quarter wave plates. As used herein, a quarter wave plate is an acoustic pad including a cavity whose depth corresponds to one quarter of the wavelength (e.g., resonant frequency) of the sound wave to be suppressed. In other words, the first acoustic pad 616a and the second acoustic pad 616b may include a panel having a cavity 618 that extends through the panel to the outer wall 612. In some examples, the acoustic pads 616a, 616b are composite honeycomb panels coupled to the outer wall 612. Due to the uneven (e.g., ridged, triangular, etc.) profiles of the first acoustic pad 616a and the second acoustic pad 616b, the depth of the cavity 618 may vary. Thus, the irregular profile of the acoustic pads 616a, 616b causes the first and second damper assemblies 602a, 602b to attenuate a range of resonant frequencies from the VBV port 214. Additionally, the nonlinearity of the acoustic pads 616a, 616b may cause acoustic waves to reflect within the body 604 in complex patterns.

[0075] Fig. 7A A method according to the teachings disclosed herein including an example fourth VBV assembly 700a (eg, a fourth VBV system) Figure 2 FIG. 2 is a partial cross-sectional side view of an example compressor 200 . Figure 7B A method according to the teachings disclosed herein including an example fifth VBV assembly 700b (eg, a fifth VBV system) Figure 2FIG. 2 is a partial cross-sectional side view of an example compressor 200 . Fig. 7A An example of a fourth VBV assembly 700a and Figure 7B Many components of the fifth VBV assembly 700b are basically combined with the above Figure 2 , Figure 3A and Figure 3B The components described in the VBV assembly 213 are similar or identical. Therefore, for the drawings disclosed herein, the same numerals represent the same elements throughout the drawings.

[0076] The fourth VBV assembly 700a includes a triangular damper assembly 702a for reducing acoustic energy generated by the VBV port 214 when air on the main flow path 212 causes the VBV port 214 to resonate. Similarly, the fifth VBV assembly 700b includes a polygonal damper assembly 702b for reducing acoustic energy from the VBV port 214 resonating.

[0077] Fig. 7A The triangular damper assembly 702a includes a triangular resonator or triangular body 704 coupled to a door 706 . Figure 7B The polygonal damper assembly 702b includes a polygonal resonator or polygonal body 708 coupled to a door 706. The door 706 includes adjacent Fig. 7A and Figure 7B The plurality of gate holes 710 of the body 704, 708 of the present invention are provided. The gate holes 710 allow air pressure oscillations to enter the body 704, 708 and be reflected internally from the interior surface of the body 704, 708 to reduce the energy of the incoming sound waves. In some examples, the resonant frequency that the triangular damper assembly 702a and the polygonal damper assembly 702b can dampen is based on the internal volume of the body 704, 708 and / or the number of gate holes 710. In addition, the polygonal body 708 includes a discharge hole 712 for adjusting or tuning the resonant frequency that the polygonal damper assembly 702b can dampen.

[0078] Fig. 7A and Figure 7B The triangular body 704 and the polygonal body 708 can collapse and / or expand based on input signals. For example, the triangular damper assembly 702a and / or the polygonal body 702b can include smart metal or shape memory alloy (SMA), which can exhibit a certain degree of elasticity based on temperature, electrical stimulation, air pressure, etc. Fig. 7A and / or Figure 7B Thus, the interior volume of the triangular damper assembly 702a and / or the polygonal damper assembly 702b may be adjusted during operation based on the current (eg, measured) resonance of the VBV cavity 228.

[0079] Figure 88 is a cross-sectional front view of a sixth VBV assembly 800 (eg, a sixth VBV system) including a damper system 802 according to the teachings disclosed herein. In some examples, Figure 8 The sixth VBV assembly 800 implements Figures 4A-4C , Fig. 6A , Figure 6B , Fig. 7A and / or Figure 7B VBV components 400, 600a, 600b, 700a and / or 700b. In addition, in some examples, Figure 8 802 Implementation of the damper system Figures 4A-4C Dual damper system 402 and / or Fig. 6A , Figure 6B , Fig. 7A and / or Figure 7B Damper assemblies 602a, 602b, 702a and / or 702b.

[0080] exist Figure 8 In the illustrated example, the damper system 802 includes a damper coupled to a door 806 (eg, Figures 4A-4C VBV door 408, etc.) and a plurality of partitions 804 and interior surfaces 808 (e.g., Figures 4A-4C the inner surface 414, etc.). Figure 8 The baffle 804 extends axially along the door 806 and defines a plurality of resonators or a plurality of bodies 810 of the damper system 802. For example, a first body 810a extends circumferentially from a first baffle 804a to a second baffle 804b. In some examples, Figure 8 The first body 810a implements Figures 4A-4C , Fig. 6A , Figure 6B , Fig. 7A and / or Figure 7B In addition, the damper system 802 includes a plurality of gate holes 811 to allow air pressure oscillations (e.g., sound waves) to enter the body 810. For example, the first body 810a includes a first gate hole 811a. The first gate hole 811a may be implemented Figures 4A-4C The first door hole 420 and / or the second door hole 422, Fig. 6A and / or Figure 6B One of the plurality of door openings 614 and / or Fig. 7A and / or Figure 7B One of the door holes 710.

[0081] In addition, Figure 8In the example shown, the damper system 802 includes a second body 810b, a third body 810c, and a fourth body 810d. The second body 810b extends circumferentially between the second diaphragm 804b and the third diaphragm 804c. The third body 810c extends circumferentially between the third diaphragm 804c and the fourth diaphragm 804d. The fourth body 810d extends circumferentially between the fourth diaphragm 804d and the fifth diaphragm 804e.

[0082] exist Figure 8 In the example shown, the baffles 804 are circumferentially spaced apart by an angle 812 (e.g., 45 degrees, 30 degrees, 60 degrees, etc.). Thus, the body 810 includes similar internal volumes (e.g., within + / - 5%). More specifically, the first baffle 804a is radially and axially aligned with a first transverse axis 814, the second baffle 804b is radially and axially aligned with a second transverse axis 816, and the third baffle 804c is radially and axially aligned with a third transverse axis 818. The transverse axes 814-818 are radially and axially aligned with the longitudinal axis 820 (e.g., Figure 1 The axial centerline axis 112 of the embodiment intersects and is orthogonal. In addition, the second transverse axis 816 is oriented at an angle 812 relative to the first transverse axis 814, and the third transverse axis 818 is oriented at an angle 812 relative to the second transverse axis 816.

[0083] In some examples, the plurality of baffles 804 are circumferentially spaced at variable distances to define different interior volumes of the body 810. Thus, the damper system 802 can suppress a range or multiple resonant frequencies (e.g., 550 Hz and 1010 Hz, 300-700 Hz, etc.) from the VBV cavity 228. Additionally or alternatively, the baffles 804 can include holes to allow acoustic waves to propagate between adjacent bodies in the body 810, which adjusts the resonant frequencies that the damper system 802 can suppress.

[0084] exist Figure 8 In the example shown, the second baffle 804b includes a first baffle hole 822a for connecting the internal volume of the first body 810a and the internal volume of the second body 810b. In addition, the fourth baffle 804d includes a second baffle hole 822b for connecting the internal volume of the third body 810c and the internal volume of the fourth body 810d. Therefore, the first baffle hole 822a combines the first body 810a and the second body 810b together, while the second baffle hole 822b combines the third body 810c and the fourth body 810d together. Therefore, for example, after the air pressure oscillation enters the first door hole 811a, the sound wave can propagate between the first body 810a and the second body 810b via the first baffle hole 822a.

[0085] The damping performance of the damper (e.g., the first body 810a) is based on the internal volume of the damper. Therefore, increasing the internal volume of the damper improves the attenuation of sound waves at lower frequencies (e.g., 250 Hz, etc.). Conversely, reducing the internal volume of the damper improves the attenuation of sound waves at higher frequencies (e.g., 700 Hz, etc.). Therefore, Figure 8 The damper system 802 includes a first baffle hole 822a for combining the internal volumes of the first body 810a and the second body 810b and enabling the damper system 802 to attenuate additional resonant frequencies of the VBV cavity 228. In some examples, other baffles in the baffles 804 also include baffle holes for further adjusting the frequency range that can be attenuated by the damper system 802. In other words, the number of baffles 804 and the number of baffle holes can be adjusted based on the resonant frequency to be attenuated by the damper system 802.

[0086] Fig. 9 A flowchart representing example machine readable instructions is shown in FIG. 1 , which may be executed to configure and / or cause a programmable circuit to implement Figure 4A , Figure 4B , Figure 4C and Figure 5 The machine-readable instructions may be one or more executable programs or a portion of an executable program for execution by a programmable circuit, such as in the following combination Fig.10 The processor circuit 1012 shown in the example processor platform 1000 discussed. The program can be implemented in software stored on one or more non-transitory computer-readable storage media, such as compact disks (CDs), floppy disks, hard disk drives (HDDs), solid-state drives (SSDs), digital versatile disks (DVDs), Blu-ray disks, volatile memory (e.g., any type of random access memory (RAM), etc.), or non-volatile memory associated with programmable circuits located in one or more hardware devices (e.g., electrically erasable programmable read-only memory (EEPROM), flash memory, HDDs, SSDs, etc.), but the entire program and / or portions thereof may alternatively be executed by one or more hardware devices other than programmable circuits, and / or implemented in firmware or dedicated hardware. The machine-readable instructions may be distributed across multiple hardware devices and / or executed by two or more hardware devices (e.g., server and client hardware devices). For example, the client hardware device may be implemented by an endpoint client hardware device (e.g., a hardware device associated with a user) or an intermediate client hardware device (e.g., a radio access network (RAN)) gateway that can facilitate communication between the server and the endpoint client hardware device. Similarly, a non-transitory computer-readable storage medium may include one or more media located in one or more hardware devices. In addition, although reference is made to Fig. 9 The flowchart shown describes an example program, but many other methods of implementing the example controller 424 may also be used. For example, the order of execution of the boxes may be changed, and / or some of the boxes described may be changed, eliminated, or combined. Additionally or alternatively, any or all of the boxes may be implemented by one or more hardware circuits (e.g., processor circuits, discrete and / or integrated analog and / or digital circuits, FPGAs, ASICs, comparators, operational amplifiers (op-amps), logic circuits, etc.), which are configured to perform corresponding operations without executing software or firmware. The programmable circuits may be distributed at different network locations and / or local to one or more hardware devices (e.g., single-core processors (e.g., single-core central processing units (CPUs)), multi-core processors in a single machine (e.g., multi-core CPUs, XPUs, etc.), multiple processors distributed on multiple servers in a server rack, multiple processors distributed on one or more server racks, CPUs and / or FPGAs in the same package (e.g., the same integrated circuit (IC) package or two or more separate housings, etc.).

[0087] The machine-readable instructions described herein may be stored in one or more of a compressed format, an encrypted format, a segmented format, a compiled format, an executable format, a packaged format, etc. The machine-readable instructions as described herein may be stored as data or data structures (e.g., as part of instructions, codes, representations of codes, etc.) that can be used to create, manufacture, and / or generate machine-executable instructions. For example, the machine-readable instructions may be segmented 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 a collection of networks (e.g., in the cloud, in an edge device, etc.). The machine-readable instructions may need to be installed, modified, adapted, updated, combined, supplemented, configured, decrypted, decompressed, unpacked, distributed, reassigned, compiled, etc., so that they can be directly read, interpreted, and / or executed by a computing device and / or other machine. For example, the machine-readable instructions may be stored in multiple parts that are individually compressed, encrypted, and / or stored on separate computing devices, where the parts, when decrypted, decompressed, and / or combined, form a set of machine-executable instructions that implement one or more operations that together may form a program such as described herein.

[0088] In another example, the machine-readable instructions may be stored in a state that can be read by a programmable circuit, but require the 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., stored settings, data inputs, recorded network addresses, etc.) before the machine-readable instructions and / or corresponding programs can be executed in whole or in part. Therefore, as used herein, a machine-readable medium may include machine-readable instructions and / or programs regardless of the particular format or state of the machine-readable instructions and / or programs when stored or otherwise at rest or when in transmission.

[0089] The machine-readable instructions described herein may 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.

[0090] As mentioned above, Fig. 9The example operations of may be implemented using executable instructions (e.g., computer and / or machine readable instructions) stored on at least one non-transitory computer and / or machine readable medium and / or medium, such as an optical storage device, a magnetic storage device, an HDD, a flash memory, a read-only memory (ROM), a CD, a DVD, a cache, any type of RAM, a register, and / or any other storage device or storage disk, where information is stored for any duration (e.g., for an extended period of time, permanently, for a brief instance, for a temporary buffer, and / or for a cache of information). As used herein, the terms non-transitory computer-readable medium, non-transitory computer-readable storage medium, non-transitory machine-readable medium, and non-transitory machine-readable storage medium are expressly defined to include any type of computer-readable storage device and / or storage disk, and to exclude propagated signals and to exclude transmission media. As used herein, the terms "computer-readable storage device" and "machine-readable storage device" are defined to include any physical (mechanical and / or electrical) structure for storing information, but to exclude propagated signals and to exclude transmission media. Examples of computer-readable storage devices and machine-readable storage devices include any type of random access memory, any type of read-only memory, solid-state memory, flash memory, optical disks, magnetic disks, disk drives, and / or redundant arrays of independent disks (RAID) systems. As used herein, the term "device" refers to a physical structure, such as a mechanical and / or electrical device, hardware, and / or circuit, which may or may not be configured by computer-readable instructions, machine-readable instructions, etc., and / or manufactured to perform computer-readable instructions, machine-readable instructions, etc.

[0091] Fig. 9 is a flow chart representing example machine readable instructions and / or example operations 900 that may be executed and / or instantiated by a programmable circuit to regulate Figures 4A-4C The dual damper system 402 can suppress the resonant frequency range. Fig. 9 The example machine readable instructions and / or operations 900 facilitate ensuring that both wide and narrow ranges of resonant frequencies of the VBV port 214 and / or the VBV cavity 228 can be suppressed using the dual damper system 402 . Fig. 9 The machine readable instructions and / or operations 900 begin at block 902 where the controller 424 detects Figure 2 , Figures 4A-4C The resonant frequency of the VBV port 214. For example, Figure 5 The interface circuit 502 from Figures 4A-4C The acoustic sensor 430 acquires the resonant frequency measurement.

[0092] At block 904, the controller 424 determines whether the resonant frequency of the VBV port 214 meets a threshold value (eg, 500 Hz, 800 Hz, 1000 Hz, etc.). Figure 5 The frequency determination circuit 504 determines whether the measured frequency satisfies (e.g., is greater than or equal to) a threshold. Additionally or alternatively, the frequency determination circuit 504 may determine whether the resonant frequency detected via the acoustic sensor 430 satisfies (e.g., is within) a first resonant frequency range corresponding to a first resonant mode of the VBV port 214 or a second resonant frequency range corresponding to a second resonant mode of the VBV port 214. When the resonant frequency does not satisfy the threshold, control proceeds to block 910. When the resonant frequency does satisfy the threshold, control proceeds to block 906.

[0093] At block 906, the controller 424 determines whether the VBV gate 408 is in Figure 4B For example, the position determination circuit 506 may obtain position measurement data from the interface circuit 502 and / or the position sensor 428 and determine whether the position measurement data corresponds to the intermediate position 404b. When the VBV gate 408 is in the intermediate position 404b, control proceeds to block 910. When the VBV gate 408 is not in the intermediate position 404b, control proceeds to block 908.

[0094] At block 908, the controller 424 moves the VBV door 408 to the intermediate position 404b. For example, the door controller circuit 508 may cause an actuator (e.g., a motor, a gear, a rod, etc.) to slide the VBV door 408 to the intermediate position 404b so that Figures 4A-4C The second door hole 422 is exposed to the VBV cavity 228 .

[0095] At block 910, the controller 424 determines whether to open the VBV door 408. For example, the position determination circuit 506 may determine whether the interface circuit 502 receives a command or input to open the VBV door 408 and allow air to flow along the VBV door 408. Figures 4A-4C In some examples, the pilot of the aircraft triggers the opening of the VBV door 408 based on flight conditions. In other examples, the interface circuit 502 receives a signal based on the Figure 2 The automatic command to open the VBV door 408 in response to a stall condition detected in the supercharger section 202 and / or the HP compressor section 204. When the VBV door 408 is not open, control passes to box 914. When the VBV door 408 is open, control passes to box 912.

[0096] At block 912, the controller 424 moves the VBV gate 408 to Figure 4CFor example, the example door controller circuit 508 causes the actuator to move the VBV door 408 to the open position 404c so that Figure 4C The VBV port outlet 218 is fully or partially unobstructed.

[0097] At block 914, controller 424 determines whether flight operations are to continue for the aircraft. For example, position determination circuitry 506 determines whether interface circuitry 502 acquires and / or receives a command and / or input corresponding to a shutdown or cessation of flight operations, such as an indication that the aircraft is landing, taxiing, idling, etc. When flight operations are to continue (e.g., the aircraft is still in flight), control returns to block 902. When flight operations are to end, control proceeds to block 916, where controller 424 moves VBV door 408 to Figure 4C For example, the door controller circuit 508 causes the actuator to move the VBV door 408 to a position that completely blocks the VBV port outlet 218. After block 916, the example machine readable instructions and / or operations 900 end.

[0098] Fig.10 is constructed to execute and / or instantiate Fig. 9 Machine readable instructions and / or operations to implement Figure 4A , Figure 4B , Figure 4C and Figure 5 4. The processor platform 1000 may be, for example, a personal computer, a workstation, a self-learning machine (e.g., a neural network), a mobile device (e.g., a cellular phone, a smart phone, an iPad, etc.). TM tablet computer), a headset (e.g., an augmented reality (AR) headset, a virtual reality (VR) headset, etc.) or other wearable device, a full authority digital engine (or electronic equipment) control (FADEC), an avionics system, or another type of computing device.

[0099] The processor platform 1000 of the illustrated example includes a processor circuit 1012. The processor circuit 1012 of the illustrated example is hardware. For example, the processor circuit 1012 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 circuit 1012 can be implemented by one or more semiconductor-based (e.g., silicon-based) devices. In this example, the processor circuit 1012 implements the example interface circuit 502, the example frequency determination circuit 504, the example position determination circuit 506, the example gate controller circuit 508, and / or more generally, the example controller 424.

[0100] The processor circuit 1012 of the illustrated example includes a local memory 1013 (e.g., cache, registers, etc.). The processor circuit 1012 of the illustrated example communicates with a main memory including a volatile memory 1014 and a non-volatile memory 1016 via a bus 1018. The volatile memory 1014 may be comprised of a synchronous dynamic random access memory (SDRAM), a dynamic random access memory (DRAM), Dynamic Random Access Memory The non-volatile memory 1016 may be implemented by flash memory and / or any other desired type of memory device. Access to the main memory 1014, 1016 of the illustrated example is controlled by a memory controller 1017.

[0101] The processor platform 1000 of the illustrated example also includes an interface circuit 1020. The interface circuit 1020 may be implemented by hardware according to any type of interface standard, such as an Ethernet interface, a universal serial bus (USB) interface, interface, a near field communication (NFC) interface, a peripheral component interconnect (PCI) interface, and / or a peripheral component interconnect express (PCIe) interface.

[0102] exist Fig.10 In the example shown, one or more input devices 1022 are connected to the interface circuit 1020. The input devices 1022 allow a user to input data and / or commands to the processor circuit 1012. The input devices 1022 may be implemented by, for example, a keyboard, buttons, a mouse, a touch screen, a track pad, a track ball, a peering device, and / or a control panel.

[0103] One or more output devices 1024 are also connected to the interface circuit 1020 of the illustrated example. The output device 1024 can be implemented, for example, by a display device (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 touch screen, etc.), a control panel, and / or a speaker. Therefore, the interface circuit 1020 of the illustrated example typically includes a graphics driver card, a graphics driver chip, and / or a graphics processor circuit (e.g., a GPU).

[0104] The interface circuitry 1020 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 the exchange of data with an external machine (e.g., any type of computing device) via the network 1026. Communications may be via, for example, an Ethernet connection, a digital subscriber line (DSL) connection, a telephone line connection, a coaxial cable system, a satellite system, a field line wireless system, a cellular telephone system, an optical connection, etc.

[0105] The processor platform 1000 of the illustrated example also includes one or more mass storage devices 1028 for storing software and / or data. Examples of such mass storage devices 1028 include magnetic storage devices, optical storage devices, floppy disk drives, HDDs, CDs, Blu-ray disk drives, redundant arrays of independent disks (RAID) systems, solid-state storage devices such as flash memory devices and / or SSDs, and DVD drives.

[0106] Can be Fig. 9 The machine-readable instructions 1032 implemented by the machine-readable instructions may be stored in the mass storage device 1028, in the volatile memory 1014, in the non-volatile memory 1016, and / or on a removable non-transitory computer-readable storage medium such as a CD or DVD.

[0107] An example variable bleed valve (VBV) assembly (also referred to herein as a "variable bleed valve apparatus" or "variable bleed valve system") is disclosed herein, which includes a VBV port extending radially outward from a compressor section of a gas turbine engine and a door positioned at the outlet of the VBV port. The VBV port can generate significant noise at a resonant frequency based on the internal dimensions of the VBV port and the closed position of the door. The resonant frequency can cause the air pressure at the VBV assembly to increase and oscillate toward a low-pressure area (e.g., a supercharger section, an inlet section, etc.) of the gas turbine engine. Such oscillations can excite mechanical components of the engine, such as rotor blades, which can reduce engine performance, damage components, increase wear, etc.

[0108] Some example VBV assemblies disclosed herein include a dual damper system coupled to a door. The dual damper system includes a body extending circumferentially around a longitudinal axis of a gas turbine engine. The body includes an internal baffle within a chamber defining a first damper and a second damper. The body also includes a first door hole that allows air to enter the first damper, a second hole that allows air to enter the second damper, and a baffle hole that allows air between the first damper and the second damper. Air pressure oscillations associated with a resonant frequency pass through the first hole and / or the second hole, and the sound waves are reflected within the first damper and / or the second damper. The reflected wave and the incident wave interact in the damper, which converts the energy of the sound wave into heat generation. The resonant frequency that the damper is able to attenuate is based on the internal dimensions of the corresponding damper.

[0109] The wall of the VBV port shields the second door aperture based on the closed position of the door. In addition, when the door is in the closed position, the first door aperture is exposed. Therefore, the first damper can attenuate noise at a first resonant frequency based on the size of the first damper and the closed position of the door. Based on the partially open position of the door, the second door aperture becomes exposed. Therefore, the second damper can attenuate noise at a second resonant frequency based on the size of the second damper and the closed position of the door. In some examples, the first damper has a larger internal volume than the second damper. Therefore, the first damper can attenuate a lower resonant frequency than the second damper. When the VBV port generates noise at the first resonant frequency, the dual damper system can actuate the door to the closed position. When the VBV port generates noise at the second frequency, the dual damper system can also actuate the door to the partially open position. In some examples, the operating conditions (e.g., air velocity) of the gas turbine engine cause the resonant frequency of the VBV port to change (e.g., increase or double). Therefore, the example dual damper system disclosed herein attenuates noise associated with multiple resonant frequencies of the VBV port.

[0110] Example devices, systems, and methods for reducing the resonant frequency of a variable exhaust valve assembly are disclosed herein. Further examples and combinations thereof include the following:

[0111] An apparatus includes: a variable bleed valve port extending radially outward from a main flow path of a gas turbine engine; a door positioned at an outlet of the variable bleed valve port, the door including a perforation; and a damper coupled to the door, the damper including a resonator adjacent the perforation of the door, the resonator defining an internal volume based on a resonant frequency of the variable bleed valve port.

[0112] An apparatus according to any preceding clause, wherein the damper extends circumferentially around the gas turbine engine, the damper comprising a first baffle and a second baffle circumferentially spaced apart from each other, the first baffle and the second baffle extending axially along the door, the first baffle and the second baffle defining the interior volume of the resonator.

[0113] An apparatus as in any preceding clause, wherein the resonator comprises an interior surface radially spaced from the door, the interior surface being non-uniform.

[0114] An apparatus as in any preceding clause, wherein the resonator is a first resonator, the damper comprising an internal baffle defining the first and second resonators, the internal baffle coupled to the door and the interior surface, the internal baffle extending circumferentially along the door.

[0115] An apparatus as in any preceding clause, wherein the internal baffle comprises a baffle aperture extending through the internal baffle between the first resonator and the second resonator.

[0116] An apparatus as in any preceding clause, wherein the perforation is a first perforation positioned adjacent the first resonator, the damper comprising a second perforation positioned adjacent the second resonator.

[0117] An apparatus according to any preceding clause, wherein the door is capable of sliding to an intermediate position between an open position and a closed position, the variable discharge valve port includes a rear wall that blocks the second perforation when the door is in the closed position, and the second perforation is exposed when the door is in the intermediate position.

[0118] The apparatus according to any of the preceding clauses further comprises a controller, a position sensor and an acoustic sensor, wherein the controller comprises a programmable circuit for: acquiring frequency data from the acoustic sensor, the frequency data corresponding to the resonant frequency of the variable exhaust valve port; acquiring position data from the position sensor, the position data corresponding to the displacement of the door; determining whether the resonant frequency of the variable exhaust valve port meets a threshold; and moving the door to the intermediate position when the resonant frequency meets the threshold.

[0119] Apparatus as claimed in any preceding clause, wherein the damper comprises an acoustic pad disposed within a body of the damper, the acoustic pad being coupled to an outer wall of the damper.

[0120] An apparatus as in any preceding clause, wherein the acoustic pad corresponds to a quarter wave plate having a plurality of cavities extending through the acoustic pad to the outer wall.

[0121] An apparatus as described in any preceding clause, wherein the acoustic pad defines a ridged surface profile.

[0122] An apparatus as described in any preceding clause wherein the acoustic pad defines a triangular surface profile.

[0123] A variable bleed valve system for a gas turbine engine, the variable bleed valve system comprising: a port extending radially outward from a main flow path of the gas turbine engine; a door positioned at an outlet of the port, the door comprising a first hole and a second hole; and a damper coupled to the door, the damper comprising: a first resonator defining a first internal volume based on a first resonant mode of the port, the first resonator being positioned adjacent to the first hole of the door; and a second resonator defining a second internal volume based on a second resonant mode of the port, the second internal volume being different from the first internal volume, the second resonator being positioned adjacent to the second hole of the door.

[0124] The variable exhaust valve system of any preceding clause, wherein the damper includes an internal baffle defining the first resonator and the second resonator, the internal baffle extending circumferentially along the door, the internal baffle including a baffle aperture extending between the first resonator and the second resonator. Example 15 includes the variable exhaust valve system of Example 13, wherein the first aperture is exposed, the second aperture is blocked when the door is in a closed position, and the second aperture is unblocked when the door is in an intermediate position.

[0125] The variable exhaust valve system according to any of the preceding clauses further includes a controller for actuating the door between a closed position, an open position and an intermediate position, the controller comprising: a position determination circuit for determining whether to move the door to the intermediate position; and a door controller circuit for moving the door between the closed position, the open position and the intermediate position.

[0126] A variable exhaust valve system according to any of the preceding clauses, wherein the controller comprises: an interface circuit for acquiring frequency data from an acoustic sensor, the frequency data corresponding to a resonant frequency of the port; and a frequency determination circuit for determining whether the resonant frequency meets a threshold, the position determination circuit for determining whether to move the door to the intermediate position based on the resonant frequency and the threshold.

[0127] A variable exhaust valve system according to any preceding clause, wherein the controller includes an interface circuit for obtaining an input corresponding to a command to move the door to the intermediate position, and the door controller circuit is used to move the door to the intermediate position based on the input.

[0128] A variable exhaust valve system according to any of the preceding clauses, wherein the controller includes an interface circuit for obtaining an air speed of the gas turbine engine, the position determination circuit for determining whether to move the door to the intermediate position based on the air speed, and the door controller circuit for moving the door to the intermediate position based on the air speed.

[0129] A method for attenuating a resonant frequency of a variable blowdown valve (VBV) port using a controller and damper system coupled to the VBV door, the method comprising: obtaining the resonant frequency of the VBV port; determining whether the resonant frequency satisfies a threshold; and moving the VBV door to an intermediate position when the resonant frequency satisfies the threshold.

[0130] A method as in any preceding clause, further comprising, after first determining that the resonant frequency satisfies the threshold, determining whether the VBV gate is in the intermediate position.

[0131] A method as in any preceding clause, wherein after a second determination that the VBV door is not in the intermediate position, moving the VBV door.

[0132] A method as in any preceding clause, further comprising determining whether the VBV door is to be opened, and upon determining that the VBV door is to be opened, moving the VBV door to an open position.

[0133] A method as in any preceding clause, further comprising determining whether to continue a flight operation and, upon determining that the flight operation will not continue, moving the VBV door to a closed position.

[0134] Although certain example systems, devices, 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, devices, and articles of manufacture that fully fall within the scope of the claims of this patent.

[0135] The following claims are incorporated into the Detailed Description by reference, with each claim standing on its own as a separate embodiment of the present disclosure.

Claims

1. A device, characterized in that: include: a variable bleed valve port extending radially outward from a main flow path of the gas turbine engine; a door positioned at an outlet of the variable drain valve port, the door including a perforation; and A damper is coupled to the door, the damper including a resonator positioned adjacent the aperture of the door, the resonator defining an interior volume based on a resonant frequency of the variable drain valve port.

2. The device according to claim 1, characterized in that The damper extends circumferentially around the gas turbine engine, the damper includes a first baffle and a second baffle circumferentially spaced apart from each other, the first baffle and the second baffle extending axially along the door, the first baffle and the second baffle defining the interior volume of the resonator.

3. The device according to claim 1, characterized in that Wherein the resonator includes an interior surface radially spaced apart from the door, the interior surface being non-uniform.

4. The device according to claim 3, characterized in that Wherein the resonator is a first resonator, the damper includes an inner baffle defining the first resonator and a second resonator, the inner baffle being coupled to the door and the interior surface, the inner baffle extending circumferentially along the door.

5. The device according to claim 4, characterized in that Wherein the internal baffle includes a baffle hole extending through the internal baffle between the first resonator and the second resonator.

6. The device according to claim 4, characterized in that Wherein the through-hole is a first through-hole positioned adjacent to the first resonator, and the damper includes a second through-hole positioned adjacent to the second resonator.

7. The device according to claim 6, characterized in that Wherein the door is slidable to an intermediate position between an open position and a closed position, the variable discharge valve port includes a rear wall that blocks the second perforation when the door is in the closed position, and the second perforation is exposed when the door is in the intermediate position.

8. The device according to claim 7, characterized in that Further comprising a controller, a position sensor and an acoustic sensor, wherein the controller comprises a programmable circuit for: acquiring frequency data from the acoustic sensor, the frequency data corresponding to the resonant frequency of the variable drain valve port; acquiring position data from the position sensor, the position data corresponding to the displacement of the door; determining whether the resonant frequency of the variable drain valve port satisfies a threshold; and When the resonant frequency meets the threshold, the door is moved to the intermediate position.

9. The device according to claim 1, characterized in that Wherein the damper includes an acoustic pad disposed within a body of the damper, the acoustic pad being coupled to an outer wall of the damper.

10. The device according to claim 9, characterized in that Wherein the acoustic pad corresponds to a quarter wave plate having a plurality of cavities extending through the acoustic pad to the outer wall.

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