Turbine engine with sound-based active control

Abstract

An engine with sound-based active control is provided. The engine includes a sound sensor coupled to an engine system, the sound sensor configured to capture noise from the engine system, one or more thrust effector devices, and an engine controller. The engine controller is configured to: determine a sound profile based on the signal from the sound sensor, determine a modified control parameter for at least one of the one or more thrust effector devices based on the sound profile and a nominal schedule; and controlling at least one of the one or more thrust effector devices according to the modified control parameter, thereby nominal the schedule.

Description

Technical Field

[0001] The present subject matter relates generally to turbine engines and, more particularly, to sound-based active control of turbine engines. Background Art

[0002] Turbine engines can include variable-pitch blades that can be pitched to affect engine output and fuel consumption. For example, the blades can be pitched from the nominal position to increase open-fan thrust at a given fan speed. This feature can be used to increase thrust at a given speed, either in transient or steady-state mode, when reduced open-fan efficiency can be tolerated. BRIEF DESCRIPTION OF THE DRAWINGS

[0003] A full and enabling description of the present disclosure, including the best mode thereof, is set forth to those skilled in the art in the specification with reference to the accompanying drawings, in which:

[0004] Figure 1 is a cross-sectional side view of an embodiment of a propulsion system according to some embodiments;

[0005] Figure 2 is a simplified block diagram of an engine control system according to some embodiments;

[0006] Figure 3 is a flow chart of a method for sound-based active engine control according to some embodiments;

[0007] Figure 4 is a simplified block diagram of an engine system according to some embodiments;

[0008] Figure 5 is a functional block diagram of sound-based active engine control according to some embodiments;

[0009] Figure 6 is a functional block diagram of sound-based active engine control according to some embodiments; and

[0010] Figure 7 is an illustration of sound-based active control of blade guides, according to some embodiments. DETAILED DESCRIPTION

[0011] Reference will now be made in detail to embodiments of the present disclosure, one or more examples of which are illustrated in the accompanying drawings. Each example is provided by way of explanation of the present disclosure, not limitation. Indeed, it will be appreciated by those skilled in the art that various modifications and variations may be made to the present disclosure without departing from the scope or spirit of the present disclosure. For example, features shown or described as part of one embodiment may be used together with another embodiment to produce yet another embodiment. Therefore, the present disclosure is intended to cover modifications and variations within the scope of the appended claims and their equivalents.

[0012] As used herein, the terms "first," "second," and "third," etc., may be used interchangeably to distinguish one component from another, and do not imply the position or importance of each component.

[0013] Unless otherwise specified herein, the terms "coupled," "fixed," "attached," and the like refer to both direct coupling, fixing, or attachment as well as indirect coupling, fixing, or attachment through one or more intermediate components or features.

[0014] The singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0015] Approximate language used herein throughout the specification and claims can be used to modify any quantitative representation that allows variation without causing a change in the basic function associated therewith. Therefore, the value modified by one or more terms (such as "approximately," "approximately," "almost," and "substantially") is not limited to the precise value specified. In some cases, approximate language may correspond to the precision of the instrument measuring the value. For example, approximate language can refer to within a margin of 1%, 2%, 4%, 10%, 15%, or 20%. These approximate margins can be applied to a single value, one or two endpoints of a defined numerical range, and / or the margin of the range between the endpoints. In this specification and claims, range limitations are combined and interchanged, and unless the context or language indicates otherwise, these ranges are identified and include all subranges contained therein. For example, all ranges disclosed herein include endpoints, and endpoints can be combined independently of each other.

[0016] In some aspects, methods and systems are described herein for increasing the efficiency of an open fan engine and improving the total engine airflow (ETAF). The uncertainty in the ETAF value is affected by several variables, such as the surface finish of fan components, the effective position of variable geometry structures, and the airflow angle caused by the aircraft's flight attitude. High fan noise, typically associated with strong airfoil wake intensity and high turbulence, can reduce ETAF.

[0017] In some embodiments, active control of relevant noise components is provided to address the dual issues of low efficiency and high noise. In some embodiments, active control involves adjusting fan pitch, outlet guide vane offset, and optimizing fan speed. Closed-loop actions can be used to reduce noise, and the effector settings used for noise mitigation can also improve fan efficiency. In some embodiments, the engine system uses acoustic data to improve engine efficiency based on the correspondence between the maximum operating efficiency point of each individual fan blade and the lower acoustic profile / noise point produced by each blade.

[0018] Aircraft cabin and community noise may be the result of interactions between certain components of turbomachinery noise and the aircraft structure. In some aspects, by reducing the triggering mechanism of turbomachinery noise using closed-loop actions, the interaction with the aircraft structure can be reduced, thereby reducing cabin and community noise. Sensor systems for measuring the triggering component of turbomachinery noise can be used herein. For example, a phased array sensor can be used to measure the triggering component of noise for input to an engine controller, such as a full authority digital engine control (FADEC). In some embodiments, a steepest descent search algorithm is incorporated into the FADEC, adjusting the effector to minimize the triggering noise component while maintaining the desired thrust. In some embodiments, the systems and methods described herein allow for simultaneous noise reduction and efficiency improvements in open fan engines.

[0019] In some aspects, an engine with sound-based active control to improve engine efficiency is provided. The engine includes a sound sensor coupled to an engine system, one or more thrust effector devices, and an engine controller. The sound sensor is configured to capture sound from the engine system. The engine controller is configured to determine a sound profile based on a signal from the sound sensor, determine modified control parameters for at least one of the one or more thrust effector devices based on the sound profile and a nominal schedule, and control the at least one of the one or more thrust effector devices according to the modified control parameters to deviate from the nominal schedule.

[0020] Now refer to Figure 1 , provides a schematic cross-sectional view of a gas turbine engine 100 according to an exemplary embodiment of the present disclosure. However, it will be understood that Figure 1The exemplary single-spool, non-ducted engine 100 shown in FIG is provided by way of example only, and in other exemplary embodiments, the engine 100 may have any other suitable configuration, including, for example, any other suitable number of shafts or spools, turbines, compressors, etc.; fixed-pitch blades, a direct drive configuration (i.e., possibly not including the gearbox 155); etc. For example, in other exemplary embodiments, the engine 100 may be a three-spool engine with an intermediate speed compressor and / or turbine. In such a configuration, it will be understood that the terms "high" and "low" used herein with respect to turbine, compressor, or spool speeds and / or pressures are convenient terms for distinguishing between components, but do not require any particular relative speeds and / or pressures, and do not exclude additional compressors, turbines, and / or spools or shafts.

[0021] Additionally or alternatively, in other exemplary embodiments, any other suitable gas turbine engine may be provided. For example, in other exemplary embodiments, the gas turbine engine may be a turboshaft engine, a turboprop engine, a turbojet engine, a rotary wing engine, a ducted engine with variable-pitch blades, or the like. Furthermore, for example, while the engine is described as a single-spool, non-ducted engine, in other embodiments, the engine may include a multi-stage open rotor configuration or a ducted engine, and aspects of the disclosure described below may be incorporated therein.

[0022] Figure 1 An engine 100 having a rotor assembly with a single stage of unducted rotor blades is provided. In this manner, the rotor assembly may be referred to herein as a "unducted fan," or the entire gas turbine engine 100 may be referred to herein as a "unducted engine," or an engine having an open rotor propulsion system 102. In addition, Figure 1 The engine includes an intermediate fan flow path extending from the compressor section to the rotor assembly on the turbine, as will be explained in more detail below. It is also contemplated that, in other exemplary embodiments, the present disclosure is compatible with engines having a duct surrounding an unducted fan. It is also contemplated that, in other exemplary embodiments, the present disclosure is compatible with turbofan engines having a third flow as described herein.

[0023] For reference, the gas turbine engine 100 defines an axial direction A, a radial direction R, and a circumferential direction C. Furthermore, the gas turbine engine 100 defines an axial centerline or longitudinal axis 112 extending along the axial direction A. Generally, the axial direction A extends parallel to the longitudinal axis 112, the radial direction R extends outwardly and inwardly from the longitudinal axis 112 in a direction orthogonal to the axial direction A, and the circumferential direction extends three hundred and sixty degrees (360°) about the longitudinal axis 112. The gas turbine engine 100 extends, for example, along the axial direction A between a forward end 114 and an aft end 116.

[0024] The gas turbine engine 100 includes a turbine 120, also referred to as the core of the gas turbine engine 100, and a rotor assembly located upstream thereof, also referred to as a fan section 150. Generally, the turbine 120 includes, in series flow order, a compressor section, a combustion section, a turbine section, and an exhaust section. In particular, as Figure 1 As shown, the turbine 120 includes a core shroud 122 that defines an annular core inlet 124. The core shroud 122 also at least partially surrounds a low-pressure system and a high-pressure system. For example, the core shroud 122 shown at least partially surrounds and supports a supercharger or low-pressure ("LP") compressor 126 for pressurizing air entering the turbine 120 through the core inlet 124. A high-pressure ("HP") multi-stage axial flow compressor 128 receives the pressurized air from the LP compressor 126 and further increases the pressure of the air. The pressurized air flows downstream to the combustors 130 of the combustion section, where fuel is injected into the pressurized air flow and ignited to increase the temperature and energy level of the pressurized air and produce high-energy combustion products.

[0025] It will be appreciated that, as used herein, the terms "high / low speed" and "high / low pressure" may be used interchangeably to refer to a high-pressure / high-speed system and a low-pressure / low-speed system. Furthermore, it will be appreciated that the terms "high" and "low" are used in the same context to distinguish between the two systems and are not meant to imply any absolute speed and / or pressure values.

[0026] The high-energy combustion products flow downstream from the combustor 130 to a high-pressure turbine 132. The high-pressure turbine 132 drives the high-pressure compressor 128 via a high-pressure shaft 136. In this regard, the high-pressure turbine 132 is drivingly coupled to the high-pressure compressor 128. The high-energy combustion products then flow to a low-pressure turbine 134. The low-pressure turbine 134 drives the low-pressure compressor 126 and components of the fan section 150 via a low-pressure shaft 138. In this regard, the low-pressure turbine 134 is drivingly coupled to components of the low-pressure compressor 126 and the fan section 150. In the exemplary embodiment, the low-pressure shaft 138 is coaxial with the high-pressure shaft 136. After driving each turbine 132, 134, the combustion products exit the turbine 120 through a core or turbine exhaust nozzle 140.

[0027] Thus, the turbine 120 defines a working gas flow path or core duct 142 extending between the core inlet 124 and the turbine exhaust nozzle 140. The core duct 142 is an annular duct located generally inwardly of the core shroud 122 along the radial direction R. The core duct 142 (e.g., the working gas flow path through the turbine 120) may be referred to as a secondary flow.

[0028] Fan section 150 includes fan 152, which in the exemplary embodiment is the main fan. Figure 1 In the illustrated embodiment, the fan 152 is an open rotor or unducted fan 152. As shown, the fan 152 includes an array of fan blades 154. The fan blades 154 are rotatable, for example, about the longitudinal axis 112. As described above, the fan 152 is drivingly coupled to the low pressure turbine 134 via the LP shaft 138. The fan 152 can be directly coupled to the LP shaft 138, for example, in a direct drive configuration. However, for Figure 1 In the illustrated embodiment, the fan 152 is coupled to the LP shaft 138 via a reduction gearbox 155 , such as in an indirect drive or gear drive configuration.

[0029] Furthermore, fan blades 154 can be arranged at equal intervals about longitudinal axis 112. Each fan blade 154 has a root and a tip, and a span defined therebetween. Each fan blade 154 defines a central blade axis 156. For this embodiment, each fan blade 154 of fan 152 is rotatable about its respective central blade axis 156, for example, in unison with one another. One or more actuators 158 are provided to facilitate such rotation and can therefore be used to change the pitch of fan blades 154 about their respective central blade axes 156.

[0030] The fan section 150 also includes a fan guide vane array 160 including fan guide vanes 162 ( Figure 1 For this embodiment, the fan guide vanes 162 are not rotatable about the longitudinal axis 112. Each fan guide vane 162 has a root and a tip and a span defined therebetween. The fan guide vanes 162 may be configured as follows: Figure 1 It is shown unobstructed, or, alternatively, may be obstructed, for example, by an annular shroud spaced outwardly in the radial direction R from the tips of the fan guide vanes 160 or attached to the fan guide vanes 62 .

[0031] Each fan guide vane 162 defines a central blade axis 164. For this embodiment, each fan guide vane 162 of the fan guide vane array 160 is rotatable about its respective central blade axis 164, e.g., in unison with one another. One or more actuators 166 are provided to facilitate such rotation and thus can be used to change the pitch of the fan guide vanes 162 about their respective central blade axis 164. However, in other embodiments, each fan guide vane 162 can be fixed or non-variable about its central blade axis 164. The fan guide vanes 162 are mounted on a fan housing 170.

[0032] like Figure 1As shown, in addition to the unducted fan 152, a ducted fan 184 is also included at the rear of the fan 152, so that the gas turbine engine 100 includes both ducted and unducted fans, both of which are used to generate thrust by the movement of air that does not pass through at least a portion of the turbine 120 (e.g., the HP compressor 128 and the combustion section of the illustrated embodiment). The ducted fan 184 can be at approximately the same axial position as the fan blades 154 or the vanes 162 and is located radially inward of the fan blades 154 or the vanes 162. For the illustrated embodiment, the ducted fan 184 is driven by the low-pressure turbine 134 (e.g., coupled to the LP shaft 138).

[0033] A fan shroud 170 annularly surrounds at least a portion of core shroud 122 and is generally positioned outboard of at least a portion of core shroud 122 along a radial direction R. In particular, a downstream section of fan shroud 170 extends over a forward portion of core shroud 22 to define a fan flow path or fan duct 172. Fan flow path or fan duct 172 may be referred to as a tertiary flow of gas turbine engine 100.

[0034] Incoming air may enter through fan duct 172 via fan duct inlet 176 and may be discharged through fan exhaust nozzle 178 to generate propulsive thrust. Fan duct 172 is an annular duct located generally outside core duct 142 along radial direction R. Fan shroud 170 and core shroud 122 are connected together and are supported by a plurality of substantially radially extending, circumferentially spaced fixed struts 174 ( Figure 1 The fan duct 172 and the core duct 142 are supported by a plurality of fixed struts 174. The fixed struts 174 may each have an aerodynamic profile to guide the air flowing therethrough. In addition to the fixed struts 174, other struts may be used to connect and support the fan shroud 170 and / or the core shroud 122. In many embodiments, the fan duct 172 and the core duct 142 may at least partially extend together (approximately axially) on opposite sides (e.g., opposite radial sides) of the core shroud 122. For example, the fan duct 172 and the core duct 142 may each extend directly from the leading edge 144 of the core shroud 122 and may partially extend together approximately axially on the opposite radial sides of the core shroud.

[0035] The gas turbine engine 100 further defines or includes an inlet duct 180. The inlet duct 180 extends between an engine inlet 182 and the core inlet 124 / fan duct inlet 176. The engine inlet 182 is generally defined at the forward end of the fan casing 170 and is positioned between the fan 152 and the fan guide vane array 160 along the axial direction A. The inlet duct 180 is an annular duct positioned inboard of the fan casing 170 along the radial direction R. Air flowing downstream along the inlet duct 180 is divided (not necessarily evenly) by the splitter or leading edge 144 of the core casing 122 into the core duct 142 and the fan duct 172. The inlet duct 180 is wider than the core duct 142 along the radial direction R. The inlet duct 180 is also wider than the fan duct 172 along the radial direction R.

[0036] See next Figure 2 , a block diagram of the engine 100 is shown. The engine 100 includes an engine controller 210 that is configured to receive inputs from the flight control section 240 and the acoustic sensor 255 and control one or more thrust effector devices 260. In some embodiments, the engine controller 210 can be a processor-based control system of the engine, such as a FADEC of the engine 100. In some embodiments, the engine controller 210 includes a FADEC and an acoustic processing module that is implemented as a software module of the FADEC or as a separate hardware module. The engine controller 210 can be configured to control the one or more thrust effector devices 260 based on signals from the acoustic sensor. In some embodiments, the engine controller 210 performs closed-loop control between the acoustic sensor and the one or more thrust effector devices 260. Reference herein Figure 3-7 The operation and functionality of engine controller 210 for sound-based active control is described in greater detail.

[0037] In some embodiments, the flight control unit 240 can be an aircraft controller, an autothrottle system, and / or other pilot-operated inputs. In some embodiments, the flight control unit 240 can set and change target engine parameters during various flight phases. In some embodiments, the target engine parameters include one or more of target thrust output, speed, torque, power pressure, or pressure ratio. In some embodiments, the engine controller 210 is configured to operate various components of the engine 100 based at least in part on signals received from the flight control unit 240.

[0038] The acoustic sensor 255 includes one or more devices for capturing acoustic data from the engine 100. In some embodiments, the acoustic sensor is part of the engine 100's onboard sensor system for measuring environmental, flight, and / or engine conditions. In some embodiments, the acoustic sensor includes a phased array acoustic sensor, a microelectromechanical (MEMS) phased array acoustic sensor, one or more directional microphones, a single-axis unidirectional microphone, a three-axis multi-directional microphone, one or more pressure transducer acoustic sensors, one or more silicon-on-insulator (SOI) acoustic sensors, and the like. Generally, the acoustic sensor 255 can be any aircraft sensor capable of measuring the amplitude, phase, and / or direction of sound from the engine. In some embodiments, the acoustic sensor is mounted near the fan section 150 or the fan guide vane array 160 of the engine 100. In some embodiments, the acoustic sensor can be mounted on or within the fan cowling 170 or the core cowling 122. In some embodiments, for ducted engines, the acoustic sensor can be mounted on the duct surrounding the fan section 150.

[0039] The thrust effector devices 260 may include one or more engine components configured to affect airflow around the engine 100. In some embodiments, the one or more thrust effector devices 260 may include variable geometry components (e.g., variable pitch blades, guide vanes, nozzles) whose geometry can be physically manipulated by an actuator to affect airflow. In some embodiments, the one or more thrust effector devices 260 may be fan speed effectors, such as fuel injectors or electric fan motors. In some embodiments, the one or more thrust effector devices 260 include one or more variable pitch blades, fuel injectors, multiple variable stator vanes, multiple inlet guide vanes, multiple outlet guide vanes, variable nozzles, or electric motors. Figure 2 This is merely a simplified block diagram, and in some embodiments, the engine controller 210 is also configured to control other engine components in addition to the one or more thrust effector devices 260, such as the reference Figure 1 Described parts.

[0040] Next reference Figure 3 , shows a method 300 for controlling an engine for active sound-based control. In some embodiments, Figure 3 One or more steps of may be performed by a processor-based control system of the engine, such as engine controller 210 of engine 100 .

[0041] In step 310, the engine 100 determines a nominal schedule. As used herein, a nominal schedule refers to a set of predefined and stored operating parameters and / or limits that determine the behavior of the engine. In some embodiments, the nominal schedule can be stored in and retrieved from onboard memory of the engine 100. In some embodiments, the engine controller 210 is configured to select control parameters according to the nominal schedule based on flight control inputs received from an aircraft controller (e.g., flight control unit 240). In some embodiments, the nominal schedule defines control parameters based on a target thrust, which is determined based on engine commands from an aircraft controller (e.g., flight control unit 240 in communication with the engine controller 210) in communication with the engine's FADEC. In some embodiments, the nominal schedule is a schedule according to a conventional engine control scheme, wherein the sequence of operating parameters to achieve a target engine output is determined based on previous testing / configuration and stored in onboard memory of the aircraft. In some embodiments, the nominal schedule can be a standard schedule used in an engine model.

[0042] In step 315, sensor data is received from a sound sensor 255 configured to capture sound / acoustic data from the engine 100. In some embodiments, the sensor data may come from one or more sound sensors 255 on and / or embedded in the engine 100. In some embodiments, the sound data may be captured by a phased array sound sensor (e.g., a MEMS phased array sound sensor). In some embodiments, the sound may include sounds from various components of the engine 100, such as sounds generated by the interaction of airflow with one or more of the fan section 150, the fan guide vane array 160, the core or turbine exhaust nozzle 140, or the fan exhaust nozzle 178. In some embodiments, the captured sound data may include frequency, amplitude, position, and / or phase information.

[0043] In step 320, the engine controller 210 determines a sound profile based on the data captured in step 315. In some embodiments, the sound profile includes one or more sound components, each sound component having a frequency, amplitude, and / or phase associated with one or more components or locations of the engine 100. In some embodiments, the sound profile is determined by isolating sound components from different sources based on the location, frequency, amplitude, and phase data of the sound waves captured by the sound sensor. In some embodiments, the engine controller 210 is configured to process the acoustic data captured by each sensor element within the sensor array and use the frequency information and / or phase information to separate sounds associated with different locations and / or components of the engine 100. In some embodiments, the sound profile isolates fan sound components associated with the self-noise of the fan and interaction sound components associated with the airflow between the rotating blades of the fan and other engine components. In some embodiments, the engine 100 includes a bandpass filter for isolating selected frequency bands from the sound data captured by the sound sensor.

[0044] In some embodiments, the sound amplitude is recorded as a root mean square (RMS) value for one or more frequency bands. In some embodiments, the engine 100 includes an analog RMS meter for calculating the RMS value of the sound captured from the sound sensor 255, or includes a software RMS calculation algorithm. Although RMS values ​​are described herein, in some embodiments, the engine controller 210 may perform a real-time fast Fourier transform (FFT) algorithm or use other parameters indicative of the sound amplitude to form a sound profile.

[0045] In some embodiments, the engine controller 210 is configured to determine whether a noise reduction trigger condition exists before determining the modified control parameters in step 330 and / or before modifying the control of the thrust effector device in step 340. In some embodiments, the engine controller 210 controls the thrust effector device 260. In some embodiments, the noise reduction trigger condition includes the engine system being in steady-state operation, such as cruise. Steady-state operation may be determined by the engine controller 210 based on the engine's sensor system and / or based on signals from the aircraft's flight control unit 240. In some embodiments, the noise reduction trigger condition is detected when a selected sound component of the sound profile has a selected frequency band with an amplitude exceeding a threshold. For example, the trigger condition may be an RMS value of a sound component associated with fan interaction noise exceeding a threshold decibel. The frequency band selection and threshold value may vary depending on the engine model and the aircraft in which the engine operates. In some embodiments, the frequency band and threshold value may be determined based on computer-based modeling, digital twin modeling, or analysis of data collected during real-world engine operation. In some embodiments, the engine controller 210 controls the one or more thrust effector devices 260 using the acoustic sensor in a closed control loop when a triggering condition exists, and controls the one or more thrust effector devices 260 using the acoustic sensor in an open control loop when a triggering condition does not exist.

[0046] In step 330, the engine controller 210 determines modified control parameters for one or more thrust effector devices 260. In some embodiments, the engine controller 210 may modify the operation of one, two, three, or more types of thrust effector devices 260 based on the acoustic profile and the nominal schedule. In some embodiments, the modified control parameters include incrementing or modifying the control of one or more thrust effector devices 260 based on the nominal schedule. For example, the modified control parameters may include increasing or decreasing fan blade pitch angles or blade pitch angles as scheduled according to the nominal schedule. In some embodiments, the thrust effector devices 260 may include variable pitch blades, variable pitch inlet guide vanes, variable pitch outlet guide vanes, turbine exhaust nozzles, fan exhaust nozzles, fuel controls, and / or electric fan motors. In some embodiments, the modified control parameters are selected to maintain thrust while reducing noise.

[0047] In some embodiments, a modified operating parameter can be determined based on an engine controller performing a pitch search by incrementally changing the pitch angle of one or more rotating blades or stationary vanes of the engine system until a local minimum sound amplitude is identified for a selected frequency band. For example, pitch changes can continue while the sound amplitude in the selected frequency band decreases, but cease when an increase in sound amplitude is detected. The pitch angle associated with the local minimum can then be used as the modified control parameter.

[0048] In some embodiments, the gas turbine engine 100 includes a memory storage device that stores a control parameter table that includes modified control parameters corresponding to one or more engine parameters, and the modified control parameters are determined based on the control parameter table. The engine parameters may include target thrust, target speed, nominally scheduled control parameters, and / or signals from one or more engine, flight, or environmental sensors. The modified control parameters may include one or more of blade pitch angle, inlet guide vane pitch angle, outlet guide vane pitch angle, fan speed, nozzle size, etc. For example, a combination of controlled variables and measured variables (including acoustic profiles) may be used to retrieve corresponding active control parameters from the table.

[0049] In some embodiments, the gas turbine engine 100 includes a memory storage device that stores an engine model, wherein modified control parameters are selected from a set of candidate control parameters based on acoustic derivatives / sound amplitudes predicted for each set of candidate control parameters using the engine model. In some embodiments, the engine controller 210 may select a set of candidate control parameters that will maintain thrust based on a lookup table and / or a nominal schedule. In some embodiments, the candidate control parameter set may be selected based on control and / or sensor signals received at the engine controller 210. The candidate control parameters are then tested against the engine model to select the candidate set with the lowest predicted sound amplitude. In some embodiments, to maintain thrust while finding the best efficiency point, the engine controller 210 may use an embedded model indicator or sensor and a calculated value indicating thrust, such as fan power using speed and torque sensors.

[0050] In some embodiments, the modified control parameters are determined based on a constrained optimization algorithm and an engine model, wherein the constrained optimization algorithm uses maintaining thrust within a threshold range as a constraint and reducing acoustic amplitude as a cost function. In some embodiments, the modified control parameters are determined based on a steepest descent algorithm.

[0051] In some embodiments, the thrust effector device 260 includes a blade pitch mechanism, such as the actuator 158, configured to change the pitch angle of rotating blades of the engine system, and the modified control parameter includes a change in the pitch angle of one or more rotating blades. In some embodiments, the modified control parameter changes the pitch angle of only a subset of the rotating blades, while the other rotating blades are pitched according to a nominal schedule.

[0052] In some embodiments, the thrust effector device 260 includes one or more blade pitch mechanisms, such as the actuator 166, configured to change the pitch angles of the inlet guide vanes and / or the outlet guide vanes, and the modified control parameter includes a change in the pitch angle of the one or more blades. In some embodiments, the modified control parameter changes the pitch angles of only a subset of the outlet guide vanes, while the other blades are pitched according to a nominal schedule.

[0053] In some embodiments, the thrust effector device 260 includes a fuel injector and / or an electric fan motor, and the modified control parameter includes a modified blade speed, which may be affected by the fuel injection rate and / or the electric motor output.

[0054] In step 340, the engine controller 210 controls one or more thrust effector devices 260 according to the modified control parameters, thereby deviating from the nominal schedule of step 310. For example, in step 340, the engine controller 210 may change the pitch of one or more fan blades and / or one or more rotor blades. In another example, the engine controller 210 may change the fan speed via fuel control or electric motor control. In some embodiments, the modified control parameters may be implemented as an adjustment or increment to the nominal schedule. In some embodiments, other engine components (e.g., fuel, electric motor) may be controlled to compensate for the effect of the modified thrust effector devices on thrust. For example, when fan pitch is turned off, fan speed may be increased via fuel control to maintain thrust.

[0055] After step 340, the engine controller 210 may continue to capture data via the sound sensor 255 and determine whether the amplitude of the component sound in the sound profile has decreased while controlling at least one of the one or more thrust effector devices according to the modified control parameters. In some embodiments, if the sound amplitude has increased or not decreased, the process may return to step 320, and the engine controller 210 may determine one or more subsequent sets of modified control parameters and control the one or more thrust effector devices 260 according to the one or more subsequent sets of modified control parameters until the sound amplitude decreases. For example, a different candidate set of modified control parameters may be selected, or a different thrust effector device may be selected.

[0056] In some embodiments, after step 340, the engine controller 210 is configured to store the modified control parameters for use in engine health analysis. In some embodiments, the engine controller 210 determines a subsequent sound profile based on the data captured by the sound sensor while controlling at least one of the one or more thrust effector devices 260 according to the modified control parameters. The subsequent sound profile can be stored in an engine model along with the modified control parameters and / or used to train the engine model using a machine learning algorithm.

[0057] In some embodiments, modified control parameters and engine parameters from successful and / or unsuccessful noise reduction can be stored as training / learning data. The control parameter tables and / or engine models can be updated through further modeling and / or machine learning based on the training / learning data. For example, in response to detecting successful noise reduction (e.g., reducing sound while maintaining thrust), target engine parameters and / or flight or engine conditions can be stored along with the applied modified control parameters.

[0058] In some embodiments, after step 340, the engine controller 210 is further configured to send the modified control parameters to an aircraft controller and / or a second engine system installed on the same aircraft to synchronize the second engine with the engine system. Figure 6 The synchronization of the engines is described in more detail.

[0059] pass Figure 3 As shown, the engine 100 can be configured to automatically modify engine control based on engine sound. By implementing the method 300 on the engine controller 210, the engine can dynamically deviate from the nominal schedule to improve engine efficiency by actively reducing sound / noise.

[0060] Next reference Figure 4, shows a simplified block diagram of an engine system according to some embodiments. The engine 100 includes an acoustic sensor positioned to capture data from the engine's fan blades 154. In some embodiments, the acoustic sensor is a phased array acoustic sensor, such as a MEMS phased array acoustic sensor, mounted on the engine 100. The signal from the acoustic sensor passes through a bandpass filter 401 to select a target acoustic frequency band. An RMS meter 402 is configured to generate an RMS value based on the output of the bandpass filter 401. The RMS value is converted to a digital signal by a converter 403 for the engine controller 210. The engine controller 210 does not then perform an RMS calculation and can directly use the received digital signal to determine whether the RMS value exceeds a threshold. For example, while the engine 100 is operating, the RMS meter 402 can continuously provide RMS values ​​to the engine controller 210. The engine controller 210 can initially follow a default schedule until the received RMS value exceeds the threshold, at which point the engine controller 210 can begin controlling one or more thrust effector devices 206 according to modified control parameters. In some embodiments, the inclusion of RMS meter 402 reduces the computational load on engine controller 210 by eliminating the need to perform software RMS calculations, and allows engine controller 210 with a low sampling rate to perform sound / noise detection at a higher sampling rate. However, in some embodiments, the engine does not include RMS meter 402, and engine controller 210 performs software RMS calculations on the received digital signals to form the sound profile of engine 100.

[0061] Next reference Figure 5 , shows a flow chart of a sound-based engine control process according to some embodiments. In some embodiments, Figure 5 One or more steps of may be performed using a processor-based control system of an engine (eg, engine controller 210 of engine 100 ).

[0062] exist Figure 5In

[0065] , acoustic sensor 255 captures data from an aircraft's engine and sends the sensed noise to embedded acoustic derivative model 510 and disturbance optimization algorithm 520. Disturbance optimization algorithm 520 selects a set of test disturbances, also referred to herein as candidate control parameters. In some embodiments, the test disturbances are selected based on one or more of target engine parameters, flight conditions, and / or a sound profile determined based on the data captured by acoustic sensor 255. Embedded acoustic derivative model 510 is used to predict the noise level associated with each test disturbance. The disturbance with the lowest predicted noise level can be selected and used to modify control geometry requirements 530. The engine controller then updates the geometry commands to the engine components based on the determined modified control parameters. For example, two or more potential variable pitch angles for a rotor blade can be used as disturbances, and embedded acoustic derivative model 510 can be used to predict the noise level associated with each potential pitch angle. In some embodiments, the embedded acoustic derivative model 510 may be used to predict noise levels associated with multiple combined parameters of two or more thrust effector devices 260 (eg, a combination of multiple rotor blade pitch angles and multiple bucket pitch angles).

[0063] Next reference Figure 6 , shows a flow chart of a sound-based engine control process with engine synchronization according to some embodiments. In some embodiments, the engine is executed using a processor-based control system of the engine (e.g., engine controller 210 of engine 100). Figure 6 One or more steps.

[0064] In some embodiments, in a multi-engine aircraft, one engine on the aircraft is designated as the leader to maintain the engines in a synchronized phase state. In such an aircraft, the aircraft controller or engine controller 210 may first determine whether the selected engine is the synchronized engine leader based on a Boolean value 615. If the engine is the leader, then the engine is synchronized based on the reference Figure 5 The same or similar processes are described to determine and update controls. Figure 6 Also shown is the control geometry determined based on the selected disturbance as a function of flight conditions stored in memory 605. The stored control geometry can be used to update the embedded acoustic derivative model 510 and / or the disturbance optimization algorithm 520. For example, the acoustic response from the changed geometry can be used as a data point to update the predictive algorithm / model used for disturbance optimization.

[0065] If the engine is not the leader, the engine is controlled via a synchronization algorithm 610 that receives control parameters from the leader engine. For example, the control parameters may include modifications to control signals for one or more of the variable pitch blades, variable pitch inlet guide vanes, variable pitch outlet guide vanes, turbine exhaust nozzle, fan exhaust nozzle, fuel control, and / or electric fan motor. The non-leader engine then synchronizes its control with the leader engine's modified control parameters, also deviating from the non-leader engine's nominal schedule. For example, the non-leader engine may increase or decrease the pitch angle of its blades or vanes relative to the nominal schedule.

[0066] Next reference Figure 7 , shows an illustration of sound-based active engine control. Figure 7 This is a conceptual diagram only. The lines shown on the diagram are only used to show relative changes in values ​​over time and may not correspond to actual numerical values.

[0067] Figure 7 The amplitude of the noise captured by the sound sensor 255 during the cruising state is shown. In some embodiments, the noise is a sound component in a specific frequency band. The noise level can increase or decrease in response to changes in control parameters and / or environmental conditions. In some embodiments, changes in control parameters during the cruising state can be made according to a nominal schedule. Figure 7 In the example shown, a change in the vane guide (VG) position (e.g., an increase in the pitch angle) results in an increase in noise. In response to the increased noise, the engine controller 210 incrementally decreases the VG pitch angle until the noise level reaches a local minimum 701. That is, further decreases in the VG pitch angle result in an increase in noise. The pitch position associated with the local minimum 701 is then used as a modified control parameter for the new cruise state, deviating from the pitch angle specified in the nominal schedule. In some embodiments, other thrust effectors can be controlled to compensate for the effect of the VG pitch on thrust, thereby maintaining thrust in the new cruise state.

[0068] The average fuel burn line shows that as noise levels increase, fuel efficiency decreases (i.e., more fuel is burned). After applying the modified control parameters, fuel efficiency improves (i.e., less fuel is burned) at the new cruise state compared to the initial cruise state. By exploiting the correlation between noise / sound amplitude at selected frequencies and average fuel burn, engine efficiency can be improved through active sound-based control.

[0069] In some embodiments, a control algorithm is provided that utilizes onboard noise / acoustic sensors to adjust fan blade pitch, thereby reducing noise and increasing fan efficiency.

[0070] In some embodiments, the control algorithm uses a model-based derivative of the fan blade pitch disturbance with respect to noise, rather than sensors, to schedule pitch. In some embodiments, the control algorithm uses inlet guide vanes, outlet guide vanes, and fan speed, rather than fan blade pitch, to influence noise.

[0071] In some embodiments, the modified control architecture allows individual blades or groups of blades to have different pitch angles to achieve local efficiency optimization. In some embodiments, the control architecture can independently manipulate individual or groups of inlet or outlet guide vanes to achieve local efficiency optimization. In some embodiments, the control algorithm can track modifications made to the pitch or variable geometry as an indicator of fan blade efficiency or health.

[0072] In one example scenario, sound-based control can be used while the aircraft is cruising at high altitude. Onboard acoustic sensors indicate blade wake noise levels. Onboard models are used to predict noise sensitivity to pitch, guide vane, or velocity disturbances while maintaining thrust. Updated control demand signals are sent to the variable geometry or fuel control, configuring the engine operating state for cruise. The updated configuration is stored for future flight information and to track blade efficiency.

[0073] Through the systems and methods described herein, an engine 100 onboard controller (eg, FADEC) may proactively modify control of one or more thrust effector devices based on real-time acoustic sensor data to improve engine performance metrics, such as increasing fuel efficiency and reducing noise levels.

[0074] Embodiments of the present disclosure may improve fuel combustion due to more efficient operation of the fan blades and reduced noise under various operating conditions.

[0075] Further aspects of the present disclosure are provided by the subject matter of the following clauses:

[0076] An engine system is provided, comprising: an acoustic sensor coupled to the engine system, the acoustic sensor configured to capture sound from the engine system; one or more thrust effector devices; and an engine controller communicatively coupled to the acoustic sensor and the one or more thrust effector devices, the engine controller configured to: determine an acoustic profile based on a signal from the acoustic sensor; determine modified control parameters for at least one of the one or more thrust effector devices based on the acoustic profile and a nominal schedule; and control the at least one of the one or more thrust effector devices to deviate from the nominal schedule based on the modified control parameters.

[0077] The engine system of any preceding clause, wherein the acoustic sensor comprises a phased array acoustic sensor and / or a micro-electromechanical phased array acoustic sensor.

[0078] An engine system as described in any preceding clause, wherein the acoustic sensor is in a closed control loop with the at least one of the one or more thrust effector devices.

[0079] An engine system according to any preceding clause, wherein in response to detecting a noise reduction trigger condition, said at least one of said one or more thrust effector devices is controlled according to said modified control parameters.

[0080] An engine system as described in any preceding clause, wherein the noise reduction trigger condition is detected when a selected sound component of the sound profile has a selected frequency band having a magnitude exceeding a threshold.

[0081] An engine system as described in any preceding clause, wherein the noise reduction trigger condition comprises the engine system being in steady-state operation.

[0082] An engine system as described in any preceding clause, wherein the sound profile is determined by isolating sound components from different sources based on position, frequency, amplitude and phase data of sound waves captured by the sound sensor.

[0083] The engine system of any preceding clause, wherein the sound profile isolates fan sound components associated with self-noise of the fan and interaction sound components associated with airflow between rotating blades of the fan and other engine components.

[0084] The engine system of any preceding clause, further comprising an analog RMS meter for calculating an RMS value of the sound captured from the sound sensor, wherein the sound profile comprises RMS values ​​of one or more frequency bands.

[0085] An engine system according to any of the preceding clauses, wherein the modified operating parameters are determined based on the engine controller performing a pitch search by incrementally changing the pitch angle of one or more rotating blades or stationary vanes of the engine system until a local minimum sound amplitude of a selected frequency band is identified.

[0086] The engine system of any preceding clause, further comprising a memory storage device storing a control parameter table including modified control parameters corresponding to one or more engine parameters, wherein the modified control parameters are determined based on the control parameter table.

[0087] An engine system as described in any preceding clause, wherein the one or more engine parameters include target thrust, control parameters of the nominal schedule, and / or signals from one or more engine, flight, or environmental sensors.

[0088] The engine system of any of the preceding clauses, further comprising a memory storage device storing an engine model, wherein the engine controller is configured to: select a plurality of candidate control parameter sets based on one or more engine parameters; predict the sound amplitude of each of the candidate control parameter sets using the engine model; and determine the modified control parameter based on the candidate control parameter set having the lowest predicted sound amplitude.

[0089] The engine system of any preceding clause, wherein the plurality of candidate control parameter sets are selected based on maintaining a target thrust for the engine system.

[0090] The engine system of any preceding clause, wherein the modified control parameters are determined based on a constrained optimization algorithm and an engine model, wherein the constrained optimization algorithm uses maintaining thrust within a threshold range as a constraint and reducing sound amplitude as a cost function.

[0091] An engine system as described in any preceding clause, wherein the modified control parameter is determined based on a steepest descent algorithm.

[0092] The engine system of any preceding clause, wherein the modified control parameters are selected to maintain a target thrust associated with the nominal schedule or to minimize a reduction in thrust of the engine system.

[0093] An engine system according to any preceding clause, wherein the one or more thrust effector devices include a blade pitch mechanism configured to change the pitch angle of rotating blades of the engine system; and wherein the modified control parameter includes a change in the pitch angle of one or more of the rotating blades.

[0094] An engine system according to any of the preceding clauses, wherein the one or more thrust effector devices include one or more blade pitch mechanisms, the one or more blade pitch mechanisms being configured to change the pitch angle of inlet guide vanes and / or outlet guide vanes, and the modified control parameters include a change in the pitch angle of one or more of the blades.

[0095] The engine system of any preceding clause, wherein the one or more thrust effector devices comprise a fuel injector or an electric fan motor, and the modified control parameter comprises a modified fan speed.

[0096] The engine system of any preceding clause, wherein the engine controller is further configured to store the modified control parameters for fan blade and / or engine health analysis.

[0097] An engine system according to any of the preceding clauses, wherein the engine controller is further configured to: determine a subsequent sound profile based on data captured by the sound sensor while controlling at least one of the one or more thrust effector devices according to the modified control parameters; and store the subsequent sound profile in the engine model together with the modified control parameters.

[0098] The engine system of any preceding clause, wherein the engine controller comprises a full authority digital engine control (FADEC) of the engine system, and the nominal schedule comprises engine commands from an aircraft controller.

[0099] The engine system of any preceding clause, wherein the engine system is mounted on an aircraft, and the engine controller is further configured to send the modified control parameters to an aircraft controller or a second engine system mounted on the aircraft to synchronize the second engine system with the engine system.

[0100] The engine system of any preceding clause, wherein the engine system is an open fan turbine engine.

[0101] A method for controlling an engine system is provided. The method includes capturing sound from the engine system using a sound sensor coupled to the engine system, the engine system including an engine controller and one or more thrust effector devices; determining, with the engine controller, a sound profile based on signals from the sound sensor; determining, with the engine controller, modified control parameters for at least one of the one or more thrust effector devices based on the sound profile and a nominal schedule; and controlling the at least one of the one or more thrust effector devices according to the modified control parameters to deviate from the nominal schedule.

[0102] A method as in any preceding clause, wherein the acoustic sensor comprises a phased array acoustic sensor and / or a micro-electromechanical phased array acoustic sensor.

[0103] A method as in any preceding clause, wherein the acoustic sensor is in a closed control loop with the at least one of the one or more thrust effector devices.

[0104] A method according to any preceding clause, wherein in response to detecting a noise reduction trigger condition, said at least one of said one or more thrust effector devices is controlled in accordance with said modified control parameters.

[0105] A method as in any preceding clause, wherein the noise reduction trigger condition is detected when a selected sound component of the sound profile has a selected frequency band having an amplitude exceeding a threshold.

[0106] A method as in any preceding clause, wherein the noise reduction trigger condition comprises the engine system being in steady-state operation.

[0107] A method as in any preceding clause, wherein the sound profile is determined by isolating sound components from different sources based on position, frequency, amplitude and phase data of sound waves captured by the sound sensor.

[0108] A method as in any preceding clause, wherein the sound profile isolates fan sound components associated with self-noise of the fan and interaction sound components associated with airflow between rotating blades of the fan and other engine components.

[0109] A method as in any preceding clause, further comprising an analog RMS meter for calculating an RMS value of the sound captured from the sound sensor, wherein the sound profile comprises RMS values ​​of one or more frequency bands.

[0110] A method according to any of the preceding clauses, wherein the modified operating parameters are determined based on the engine controller performing a pitch search by incrementally changing the pitch angle of one or more rotating blades or stationary vanes of the engine system until a local minimum sound amplitude of a selected frequency band is identified.

[0111] The method of any preceding clause, further comprising a memory storage device storing a control parameter table comprising modified control parameters corresponding to one or more engine parameters, wherein the modified control parameters are determined based on the control parameter table.

[0112] A method as in any preceding clause, wherein said one or more engine parameters comprise target thrust, control parameters of said nominal schedule and / or signals from one or more engine, flight or environmental sensors.

[0113] The method according to any of the preceding clauses further includes a memory storage device storing an engine model, wherein the engine controller is configured to: select a plurality of candidate control parameter sets based on one or more engine parameters; predict the sound amplitude of each of the candidate control parameter sets using the engine model; and determine the modified control parameter based on the candidate control parameter set having the lowest predicted sound amplitude.

[0114] A method as in any preceding clause, wherein the plurality of candidate control parameter sets are selected based on maintaining a target thrust for the engine system.

[0115] A method as in any preceding clause, wherein the modified control parameters are determined based on a constrained optimization algorithm and an engine model, wherein the constrained optimization algorithm uses maintaining thrust within a threshold range as a constraint and reducing sound amplitude as a cost function.

[0116] A method as in any preceding clause, wherein the modified control parameter is determined based on a steepest descent algorithm.

[0117] A method as in any preceding clause, wherein the modified control parameters are selected to maintain a target thrust associated with the nominal schedule or to minimize a reduction in thrust of the engine system.

[0118] A method according to any of the preceding clauses, wherein the one or more thrust effector devices include a blade pitch mechanism configured to change the pitch angle of rotating blades of the engine system; and wherein the modified control parameter includes a change in the pitch angle of one or more of the rotating blades.

[0119] A method according to any of the preceding clauses, wherein the one or more thrust effector devices include one or more blade pitch mechanisms, the one or more blade pitch mechanisms being configured to change the pitch angle of inlet guide vanes and / or outlet guide vanes, and the modified control parameters include a change in the pitch angle of one or more of the blades.

[0120] A method as in any preceding clause, wherein the one or more thrust effector devices comprise a fuel injector or an electric fan motor, and the modified control parameter comprises a modified fan speed.

[0121] A method as in any preceding clause, wherein the engine controller is further configured to store the modified control parameters for fan blade and / or engine health analysis.

[0122] A method according to any of the preceding clauses, wherein the engine controller is further configured to: determine a subsequent sound profile based on data captured by the sound sensor while controlling at least one of the one or more thrust effector devices according to the modified control parameters; and store the subsequent sound profile in the engine model together with the modified control parameters.

[0123] A method as in any preceding clause, wherein the engine controller comprises a full authority digital engine control (FADEC) of the engine system, and the nominal schedule comprises engine commands from an aircraft controller.

[0124] A method according to any of the preceding clauses, wherein the engine system is mounted on an aircraft, and the engine controller is further configured to send the modified control parameters to an aircraft controller or a second engine system mounted on the aircraft to synchronize the second engine system with the engine system.

[0125] A method as in any preceding clause, wherein the engine system is an open fan turbine engine.

[0126] An engine controller device is provided, comprising: a processor executing computer-readable instructions stored on a computer-readable storage medium, the computer-readable instructions configured to cause the processor to: receive a signal from a sound sensor coupled to an engine system, the sound sensor configured to capture sound from the engine system; determine a sound profile based on the signal from the sound sensor; determine a modified control parameter for at least one of one or more thrust effector devices of the engine system based on the sound profile and a nominal schedule; and control the at least one of the one or more thrust effector devices to deviate from the nominal schedule based on the modified control parameter.

[0127] This written description uses examples to disclose the disclosure, including the best mode, and to enable any person skilled in the art to practice the disclosure, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the disclosure is defined by the claims and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.

Claims

1. An engine system, characterized in that: include: a sound sensor coupled to the engine system, the sound sensor configured to capture sound from the engine system; one or more thrust effector devices; as well as an engine controller communicatively coupled to the acoustic sensor and the one or more thrust effector devices, the engine controller configured to: determining a sound profile based on a signal from the sound sensor; determining modified control parameters for at least one of the one or more thrust effector devices based on the acoustic profile and the nominal schedule; and The at least one of the one or more thrust effector devices is controlled in accordance with the modified control parameters to deviate from the nominal schedule.

2. The engine system according to claim 1, characterized in that The acoustic sensor comprises one or more of a phased array acoustic sensor or a micro-electromechanical phased array acoustic sensor.

3. The engine system according to claim 1, wherein: Wherein the acoustic sensor is in a closed control loop with the at least one of the one or more thrust effector devices.

4. The engine system according to claim 1, wherein: wherein in response to detecting a noise reduction trigger condition, said at least one of said one or more thrust effector devices is controlled according to said modified control parameter.

5. The engine system according to claim 4, characterized in that The noise reduction triggering condition includes the engine system being in steady-state operation.

6. The engine system according to claim 1, wherein: The sound profile is determined by isolating sound components from different sources based on the position, frequency, amplitude and phase data of the sound waves captured by the sound sensor.

7. The engine system according to claim 1, wherein: The sound profile isolates fan sound components associated with self-noise of the fan and interaction sound components associated with airflow between rotating blades of the fan and other engine components.

8. The engine system according to claim 1, wherein: Further included is an analog RMS meter for calculating an RMS value of the sound captured from the sound sensor, wherein the sound profile includes RMS values ​​of one or more frequency bands.

9. The engine system according to claim 1, wherein: The modified operating parameters are determined based on the engine controller performing a pitch search by incrementally changing the pitch angle of one or more rotating blades or stationary vanes of the engine system until a local minimum acoustic amplitude of a selected frequency band is identified.

10. The engine system according to claim 1, wherein: Further included is a memory storage device storing a control parameter table including modified control parameters corresponding to one or more engine parameters, wherein the modified control parameters are determined based on the control parameter table.

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