Adaptive flow control for engine nacelles

Abstract

The present disclosure relates to adaptive flow control for engine nacelles. An inlet flow distortion control system employs a plurality of flow control devices forming at least one array integrated in an inner surface of an inlet. The at least one array extends over a range of azimuthal angles relative to a normal flow axis of the inlet and has a plurality of circumferential rows spaced apart with increasing distance from a protrusion of the inlet. A control system is operatively connected to the flow control devices and adapted to activate the flow control devices in selected sub-arrays of the array in response to predetermined flight conditions.

Description

Technical Field

[0001] The present invention generally relates to the field of jet propulsion for aircraft fans employing inlets with a low ratio of inlet length to engine fan diameter (L / D), and more specifically, to an inlet flow control system that employs an array of flow control devices on the inner surface of the fan inlet to mitigate flow distortion in the inlet at low speeds due to crosswinds, high angles of attack, and ground eddies. Background Technology

[0002] Modern commercial aircraft primarily employ fan-jet engines. Current inlet designs are oriented with a high inlet length-to-fan diameter (L / D) ratio. A L / D greater than 0.5 is typical for current engines to maintain the required flow profile at the fan surface under crosswinds and other flight conditions. Future inlets are projected to have an L / D below 0.5. The lower limit of L / D appears to exist within the current inlet design capabilities, based on the inlet length required to mitigate inlet flow distortion during low-speed takeoff and landing. However, an L / D lower than the current lower limit would improve all other aerodynamic aspects of the mission (97% of the mission profile for a 1-hour commercial flight). This improved aerodynamic performance, due to the lower L / D, reduces the aircraft's fuel consumption. Current inlet designs meet the aforementioned low-speed takeoff and landing requirements (approximately two minutes of flight for a typical commercial aircraft) and are therefore over-designed during the climb / cruise / descent phases. This "over-design" results in a fuel consumption penalty for the remainder of the mission due to increased drag and weight.

[0003] Current flow control solutions applied to aircraft inlets offer non-modular designs with fixed flow control configurations. Because the separated flow regions are dynamic and can move within the inlet, any given flow control input may become less efficient (or even ineffective). Therefore, existing flow control solutions may "lack" a separated flow region. Such system configurations require increased output from the flow control system to continue successfully combating flow separation under varying flight conditions, thereby increasing the input (e.g., higher input mass flow velocity for aerodynamic flow control systems). Consequently, such systems can impact size, weight, and power requirements. Summary of the Invention

[0004] An exemplary embodiment of the inlet flow distortion control system employs multiple flow control devices, forming at least one array integrated within the inner surface of the inlet. The at least one array extends in an azimuth range relative to the normal flow axis of the inlet and has multiple circumferential rows spaced apart from the inlet highlight by increasing distances. The control system is operatively connected to the flow control devices and is adapted to activate the flow control devices in selected subarrays of the array in response to predetermined flight conditions.

[0005] An exemplary embodiment provides a method for flow control in a low-L / D fan injection inlet. A status signal and a mass flow signal are received in a controller. In response to the status and mass flow signals, a control output from the controller is sent to one or more of a plurality of flow control devices in an array on the inner surface of the inlet, and flow distortion in the inlet is reduced. Attached Figure Description

[0006] The features, functions, and advantages already discussed can be implemented independently in various embodiments or combined in other embodiments, further details of which can be seen in the following description and figures.

[0007] Figure 1 This is an illustration of a commercial aircraft with a high bypass ratio turbofan engine, showing an example implementation of engine nacelle adaptive flow control.

[0008] Figure 2 This is an illustration of the engine compartment entrance, showing an array of flow control devices used in the example implementation;

[0009] Figure 3 This is a plan view of a transverse array of flow control devices implemented on the angular segment of the inlet;

[0010] Figure 4 It represents the flow distortion pattern in the inlet under various mass flow rates and crosswind conditions;

[0011] Figure 5 It is a graph of the inlet distortion coefficient under conditions of no crosswind and 30 crosswinds;

[0012] Figures 6A to 6C This is a planar schematic diagram of a subarray of a flow control device used to activate crosswind compensation at different mass flow rates;

[0013] Figures 7A to 7C It corresponds to Figures 6A to 6C A graph showing the maximum ingress distortion coefficient activated by the subarray in the image;

[0014] Figure 8A It is a graph showing the maximum inlet distortion correction achieved by activating different subarrays at a selected mass flow rate;

[0015] Figure 8B Is Figure 8A The representation shown is an improved flow distortion pattern in the inlet under various inlet mass flow rates with a crosswind condition of 30 kt and under control.

[0016] Figure 9This is a plan view of the bottom array of a flow control device for flow control in high angle of attack or ground eddy current scenarios;

[0017] Figure 10 This is a block diagram of an example control system;

[0018] Figures 11A to 11D It is a representation of concentric cylinders spaced apart between the inner surface of the inlet and the pressure chamber, used to control the jet actuation of the flow nozzle as a flow control device;

[0019] Figures 11E to 11O It is a representation of an annular perforated plate, which controls flow communication through a conduit between the inner surface of the inlet and the pressure chamber, and is used to control the jet actuation of the flow nozzle as a flow control device;

[0020] Figure 12 It represents the individual control of the flow nozzles that form an array of flow control devices;

[0021] Figure 13 It represents the control of the manifold flow nozzle as a flow control device;

[0022] Figure 14 It represents the control of a single synthetic nozzle that forms an array of flow control devices;

[0023] Figure 15 It is a representation of the control of a single deployed eddy current generator as an array of flow control devices; and

[0024] Figure 16 This is a flowchart of a method for flow control in the injection inlet of a low L / D fan. Detailed Implementation

[0025] The embodiments described herein provide an array of one or more azimuth-radial flow control devices integrated on the inner surface of the inlet. The total azimuth-radial coverage of the flow control array is determined based on the flow separation domain along the entire flight envelope, and subsets or control configurations of the array can be activated under specific flow conditions.

[0026] Refer to the attached diagram. Figure 1 A large commercial aircraft 10 employing a high-bypass-ratio turbofan engine 12 with an ultra-short nacelle 14 is depicted, wherein the embodiment described herein is adopted. While the embodiment described herein relates to commercial aircraft, this disclosure is applicable to any low L / D application or other inlet with asymmetric flow distortion. Figure 2As seen, multiple flow control devices 16 are integrated within the inner surface 18 of the inlet 20 of the ultra-short nacelle 14, forming one or more arrays (described in more detail later) extending axially rearward from the inlet protrusion 21 (or edge). The inlet 20 has a normal flow axis 15. As defined herein, a “flow control device” may include a combination of aerodynamic nozzles, fluid oscillators, stabilized nozzles, unstabilized pulsed nozzles, non-aerodynamic flow control systems, and zero net mass flow devices, such as electronically synthesized nozzles or identification systems. In alternative embodiments, an array of deployable vortex generators or other mechanical devices (pins, etc.) may replace the orifices of the fluid nozzles. These devices can be retracted, flush with the inner surface of the inlet, and then deployed in a pattern within the array to achieve the desired flow pattern. Such mechanical devices may also be deployed and retracted periodically at varying frequencies. The control system (described in more detail below) operatively connected to the flow control device 16 is adapted to activate or modulate the flow control device in the selected subarray in response to the inlet flow state indicated by a predetermined flight condition or a measured flow parameter within the inlet 20.

[0027] Figure 3 The plan view shows arrays 22a and 22b of left and right flow control devices located on the inner surface 18 of inlet 20. The right array 22a extends over an azimuth range 23a (between 40° and 150° relative to the normal flow axis 15 for the example embodiment) determined based on an example flow separation domain of right-side wind (defined herein as flow from right to left relative to the figures), while the left array 22b extends over an azimuth range 23b (between 40° and 150° for the example embodiment) determined based on a flow separation domain of left-side wind (defined herein as flow from left to right relative to the figures). Each array 22a and 22b employs a plurality of circumferential rows 24a, 24b, 24c, 24d spaced apart from the inlet highlight 21 by increasing first, second, third, and fourth axial distances 26a, 26b, 26c, 26d. The left array 22b is described, with the circumferential rows 24a and 24b having a first arrangement of flow control devices extending over the full azimuth range of the array. Row 24c has an azimuth range that decreases centered at 270° and extends between 260° and 280°, while row 24d has a further reduced azimuth range (a single nozzle at 270° in the example shown). For the example embodiment, each row has a flow control device 16 at every 10° azimuth angle within the range. Although shown as a circular orifice in the figures for the example embodiment, the flow control device 16 may have a slotted orifice or an alternative geometry.

[0028] Figure 3 The illustrated embodiment provides left and right arrays for responding to the vector components of the left and right side airflow relative to the normal flow axis 15. Figure 4This shows the mass flow rate (defined as...) Dimensionless (mass flow rate divided by the maximum inlet mass flow rate) Figure 401; Figure 402; and Figure 403 is a visualization of the flow distortion in the inlet of the left-side wind component with a crosswind of 0 kt. This figure shows a very small distortion in the inlet under the condition of a 0 kt crosswind. However, when the flow rate... Figure 404; Figure 405; and At Figure 406, the crosswind component with a value of 30 kt exhibits significant distortion.

[0029] For the purpose of quantitatively describing the flow distortion in this paper, the inlet distortion coefficient IDC is defined as follows: in, It is the mean pressure, P min It is the minimum pressure on the i-th ring (measured on a circumferential ring of constant radius). Defined as IDC. max The maximum distortion corresponds to the maximum IDC and produces the maximum circumferential distortion seen at the inlet. Figure 5 IDCs are provided for the 0kt condition (trace 502) and 30kt condition (trace 504) in the described embodiment where the flow control device 16 is not activated. max The image.

[0030] like Figures 6A to 6C As shown, selective activation of the flow control device 16 in the subarray within the left array 22b is achieved to mitigate the effects of flow control relative to the subarray. Figure 4 and Figure 5 The flow distortion caused by the left-side wind component. For the example shown in the attached figures... Figure 6A The activation of the first subarray 28a shown leads to, as Figure 7A The diagram shows the IDC over the entire mass flow range of trace 701. max The modifications. Similarly, Figure 6B The activation of the second subarray 28b shown results in, as Figure 7B The image shows the IDC of trace 702. max The modification, and Figure 6C The activation of the third subarray 28c shown results in, as Figure 7C The image shows the IDC of trace 703. max Modifications were made. In an example control scenario, the active subarrays switch depending on the mass flow rate range; the first subarray 28a is active when the mass flow rate is between 0 and 0.48, the second subarray 28b is active when the mass flow rate is between 0.48 and 0.82, and the third subarray 28c is active when the mass flow rate is between 0.82 and 1. This results in the IDC shown in Figure 8.max The modification involves the trace segment 801 being connected to the IDC over a flow range of 0 to 0.48 of the activated first subarray 28a. max Modifications were made regarding the IDC of trace segment 802 and the activation of the second subarray 28b within a flow range of 0.48 to 0.82. max The modification relates to the IDC of trace segment 803 and the 0.82 to 1.0 flow range of the activated third subarray 28c. max Related to IDC across the entire flow range. max The overall reduction is optimized. The resulting reduction in flow distortion is as follows: Figure 8B As shown. In other embodiments (or in alternative operations to the illustrated embodiments), various combinations of flow control devices in the subarray and individual or combined activation of the subarray can be employed to adjust flow correction based on changes in crosswind rate and inlet mass flow rate.

[0031] The operation of array 22a for the right wind component is similar to the operation of array 22b for the left wind component, as described above.

[0032] In an alternative implementation, one or more flow control arrays 22c may be employed, either alone or in addition to the flow control arrays 22a, 22b for crosswind distortion correction, within the azimuth range 23c on the bottom of the inlet inner surface, for example, as... Figure 9 As shown as an example, 130° to 230° is used to accommodate flow distortion caused by high angle of attack (aircraft pitch) scenarios or ground eddy scenarios, where flow separation occurs substantially at the bottom of the inner surface of the inlet or on one side or beam side of the inlet. The operation of array 22c is analogous to the operation disclosed for array 22b and can be combined with the operation of array 22a or array 22b.

[0033] Although this document describes specific flight conditions such as crosswinds, angle of attack, and ground eddies, this implementation provides flow control capabilities based on generalized flight conditions (including flow velocities constituting the instantaneous flight state, flow angles relative to the engine, engine inlet mass flow rate, and altitude).

[0034] like Figure 10As shown, the control system 1002 employs a controller 1004 that receives condition input 1006 from one or more condition sensors 1008. The condition sensors 1008 may be pressure sensors or other sensing systems such as optical or ultrasonic detectors for boundary layer separation or internal turbulence in inlet 20. Crosswind direction and velocity (or angle of attack) may be provided by various aircraft onboard systems or as external inputs to the condition signal 1009 received by the controller 1004. One or more mass flow sensors 1010 also provide an inlet mass flow input 1012 to the controller 1004. The inlet mass flow input 1012 may alternatively be derived from external inputs such as thrust rod position or fan speed. In response to the inlet state determined by the condition signal 1009, the condition sensors 1008, and the mass flow sensors 1010, the controller 1004 provides a control signal 1013 to one or more activation devices 1014, which are configured to activate individual or sub-array flow control devices 16 in the previously described array. As described in more detail later, the control signal may also provide or modulate the jet flow rate or vortex generator deployment frequency for the flow control device 16. The controller may operate in open-loop mode based on the status signal 1009 and the inlet mass flow input 1012, or may provide closed-loop control using feedback from the status sensor 1008 and the mass flow sensor 1010.

[0035] In the open-loop implementation, the controller 1004 does not react to the flow field conditions. Instead, it operates only on a pre-planned schedule, targeting specific actuation intensity and location based on measured flight conditions at the time, such as current engine inlet mass flow rate, flight speed, crosswind speed, and direction and altitude.

[0036] In the closed-loop implementation, the controller 1004 responds to the "condition" of the flow field at the inlet. The mass flow sensor 1010 and the condition sensor 1008 provide continuous monitoring to the controller 1004, causing the controller to continuously provide updated control signals 1013 to the activation device 1014. The flow control system is activated only when the controller 1004 has determined that flow separation has occurred (or based on the anticipated presence of a condition).

[0037] For the above combination, in the open-loop configuration, the controller 1004 actuates a predetermined array or subarray based on the strength of the flow control device 16 targeting the desired flow separation region, using the state signal 1009. This is then converted to continuous monitoring of the mass flow sensor 1010 and the state sensor 1008 for the closed-loop configuration. The array or subarray in the closed-loop configuration can be determined in real time and may include multiple or single flow control devices 16 responding in real time to the state sensor 1008, depending on the configuration of the activation device described later.

[0038] exist Figure 11A and Figure 11BIn the example embodiment shown in the exploded diagram, the flow control device 16 is a control nozzle, and the activation device 1014 is one or more concentric cylinders 1102 or cylindrical segments (the wall thickness of the components is exaggerated for clarity) spaced between the inner surface 18 of the inlet and the pressure chamber 1104. The pressure chamber 1104 is connected to an exhaust system 1105 or other pressure source. The concentric cylinders have an array of holes 1106a-1106d, which allows for... Figure 11C The “closed” position shown is rotated to align with the control nozzles in the circumferential rows 24a-24d, thereby causing the subarrays 28a, 28b, or 28c to open toward the pressure chamber 1104 to obtain Figure 11D The nozzle flow is shown. The activation device 1014 is a motor that engages with the concentric cylinder 1102 to rotate the cylinder from a closed position to an aligned position. Although in Figures 11A to 11D The diagram shows a single orifice corresponding one-to-one with the flow control devices in the corresponding row, but each concentric cylinder can rotate in multiple steps within 10° intervals of the device, wherein the stepped array has orifice or blank closures to accommodate different azimuth ranges of specific subsets of the flow control devices in the row, thereby obtaining the previously described subarrays 28a, 28b, and 28c. In an alternative embodiment, a single sliding or rotatable door can provide closed and open states for the flow control device 16.

[0039] exist Figures 11E to 11O In a similar example embodiment shown, the flow control device 16 is a control nozzle, and the activation device 1014 is one or more perforated annular plates 1110 or plate segments, substantially perpendicular to the normal flow axis 15, located between the inner inlet surface 18 and the outer surface 19, having a conduit 1112 extending from the interface 1114 of the annular plate 1110 to the flow control device 16 on the inner inlet surface 18. A second interface 1116 of the plate communicates with a pressure chamber 1118. As in previous embodiments, the pressure chamber 1118 is connected to an exhaust system or other pressure source. The annular plate 1110 has, as shown in the previous embodiments... Figure 11F The aperture arrays 1120a-1120d shown can be obtained from, for example Figure 11E and Figure 11N and Figure 11O The "closed" position shown is rotated to align with the control nozzles in the circumferential rows 24a-24d to open the various subarrays into the pressure chamber 1118 to achieve, as Figure 11F and Figure 11G The jet flow shown is as follows: Figure 11H and Figure 11I , Figure 11J and Figure 11K as well as Figure 11L and Figure 11MThe full subarray shown is partially open. The activation device 1014 is a motor that engages with the annular plate 1110 to rotate the plate from a closed position to multiple aligned positions around the normal flow axis 15. Although in Figures 11A to 11D The diagram shows a single hole corresponding one-to-one with the flow control device in the corresponding row, but the annular plate 1110 can be rotated in multiple steps within 10° intervals of the device, wherein the stepped array has hole or blank closures to accommodate different azimuth ranges of specific subsets of the flow control devices in the row, thereby obtaining multiple subarrays.

[0040] exist Figure 12 In another example embodiment, schematically illustrated, the electronically or hydraulically controlled valve 1202 provides an activation device to connect a corresponding flow control device 16 to a pressure source 1203, such as an exhaust system. The controller 1004 activates one or more selected valves 1202 using control signals 1013 for a predetermined array or subarray of flow control devices. Figure 13 As shown, in contrast to the control of a single flow control device, manifold valve 1302 can be connected between a pressure source and one or more manifolds 1304, and is in fluid communication with an array or subarrays 28a, 28b of flow control devices 16.

[0041] Such as about Figures 11A to 13 The described implementation can also be applied to a pneumatic flow control system that uses suction instead of blowing, i.e., jetting, or a combination of suction and blowing.

[0042] like Figure 14 As shown, the synthetic nozzle 1402 can be used as a flow control device at an array position on the inner surface 18 of the inlet 20, and can be directly activated by the controller 1004 to provide flow modification in the inlet. The power connection 1404 and the horizontal control 1406 (e.g., pulse width modulation (PWM) injection modulation) can be directly controlled by the controller 1004 via the repeater 1408 or other suitable control element to activate each of the synthetic nozzles controllable by the controller 1004 to generate the selected subarrays 28a, 28b, 28c.

[0043] Figure 15 An alternative embodiment with an array of deployable eddy current generators or other mechanical devices such as pin 1502 is schematically shown, which are extended and retracted in response to a control signal 1013 by a solenoid manipulator 1504 or similar component acting as an activation device. Pin 1502 can be periodically extended and retracted at varying frequencies to achieve the desired flow modification.

[0044] like Figure 16As shown, the disclosed embodiment provides a method 1600 for flow control in the inlet of a low L / D fan nozzle. A controller receives a status signal and an inlet mass flow signal (step 1602). In response to the status and inlet mass flow signals, the controller provides a control output to one or more of a plurality of flow control devices in an array on the inner surface of the inlet to reduce flow distortion in the inlet (step 1604). The controller receives a status signal from one or more status sensors (step 1606). In response to the inlet mass flow signal or the status signal, the controller modulates the flow control devices to form a subarray to optimize the reduction of flow distortion in the inlet (step 1608). For various disclosed embodiments, the step of modulating the flow control devices can be accomplished by: selectively aligning concentric cylinders with an array of orifices to connect a corresponding subarray of the flow control devices to a pressure source; selectively opening a valve between the pressure source and one or more flow control devices to form a subarray; selectively opening a valve between the pressure source and one or more manifolds connected to the subarray of the plurality of flow control devices; selectively activating a synthesis device to form a subarray; or selectively deploying and retracting a deployable vortex generator to form a subarray.

[0045] Various embodiments have now been described in detail in accordance with the requirements of patent law, and those skilled in the art will recognize modifications and substitutions to the specific embodiments disclosed herein. Such modifications are within the scope and intent of the appended claims. In the specification and claims, the terms “comprising,” “incorporating,” “incorporates,” or “incorporating,” “include,” “includes,” or “including,” “has,” “have,” or “having,” and “contain,” “contains,” or “containing” are intended for disclosure and may include additional or equivalent elements. The term “substantially” as used in the specification and claims means that the stated feature, parameter, or value does not need to be implemented precisely, but rather may have deviations or variations, including, for example, tolerances, measurement errors, measurement accuracy limitations, and other factors known to those skilled in the art, in an amount that does not preclude the effect that the feature is intended to provide. As used herein, the terms “right,” “left,” “front,” “back,” “up,” “down,” and “clockwise,” “counterclockwise,” are employed to describe relative positioning and movement with respect to the accompanying drawings, and in addition to the specific embodiments disclosed, exemplary embodiments, depending on the orientation of the actual embodiment, may be replaced or reversed by appropriate descriptors such as “first,” “second,” “top,” “bottom,” or “left,” “right.”

[0046] Item 1. An inlet flow distortion control system, comprising: a plurality of flow control devices integrated in an inner surface of an inlet, forming at least one array, the at least one array extending in an azimuth range relative to the normal flow axis of the inlet and having a plurality of circumferential rows spaced apart from a protrusion of the inlet by an increasing axial distance; and a control system operatively connected to the plurality of flow control devices, the control system being adapted to activate the flow control devices in a selected subarray of the at least one array in response to an inlet flow state indicated by a predetermined flight condition or flow parameters measured within the inlet.

[0047] Item 2. The inlet flow distortion control system according to Item 1, wherein at least one array comprises a right array and a left array, the right array having an azimuth range determined based on a right-side airflow separation domain, and the left array having an azimuth range determined based on a left-side airflow separation domain.

[0048] Item 3. The inlet flow distortion control system according to Item 1 or 2, wherein at least one array comprises an array extending over an azimuth range at the bottom of the inner surface of the inlet to accommodate the control of flow distortion caused by high angle of attack or ground eddies.

[0049] Item 4. The inlet flow distortion control system according to Item 2 or 3, wherein the left array and the right array each include a plurality of circumferential rows spaced apart from the inlet protrusion by an increased first axial distance, a second axial distance, a third axial distance and a fourth axial distance.

[0050] Item 5. The inlet flow distortion control system according to Item 4, wherein, for each of the right array and the left array, the first of the plurality of circumferential rows includes a flow control device extending over the azimuth range of each of the right array and the left array, the second of the plurality of circumferential rows includes a flow control device extending over a reduced azimuth range of each of the right array and the left array, and the third of the plurality of circumferential rows includes a flow control device extending over a further reduced azimuth range of each of the right array and the left array.

[0051] Item 6. The inlet flow distortion control system according to Item 5, wherein the control system comprises: a controller that receives a status signal or condition input for crosswind or angle of attack; a mass flow input to the controller; and one or more activation devices that receive an output signal from the controller in response to the mass flow input and the status signal or condition input, the one or more activation devices being configured to activate a flow control device in one of a selected subarray.

[0052] Item 7. The inlet flow distortion control system according to Item 6, wherein the one or more activation devices comprise: one or more concentric cylinders spaced apart between the inner surface of the inlet and the pressure chamber, the one or more concentric cylinders having an array of holes rotatable from a closed position to be aligned with one or more control nozzle rows; and a pressure source connected to the pressure chamber.

[0053] Item 8. The inlet flow distortion control system according to Item 7, wherein the pressure source is an exhaust system.

[0054] Item 9. The inlet flow distortion control system according to Item 7 or 8, wherein one or more concentric cylinders comprise a plurality of concentric cylinders, each concentric cylinder being aligned with a corresponding one of one or more rows of control nozzles to open one of the selected subarrays into the pressure chamber.

[0055] Item 10. The inlet flow distortion control system according to any one of items 6-9, wherein one or more activation devices include one or more valves, each valve being connected to a corresponding flow control device among a plurality of flow control devices.

[0056] Item 11. The inlet flow distortion control system according to Item 10, further comprising at least one manifold connecting one of one or more valves to a selected subarray of at least one array of a plurality of flow control devices.

[0057] Item 12. The inlet flow distortion control system according to any one of items 6-11, wherein each of the plurality of flow control devices includes a synthesizing nozzle, and further includes: a power connection to each synthesizing nozzle; and a level controller connected to each synthesizing nozzle via a repeater, capable of controlling to generate selected subarrays of at least one array.

[0058] Item 13. The inlet flow distortion control system according to any one of items 6-12, wherein each of the plurality of flow control devices includes an expanded eddy current generator, and wherein one or more activation devices each includes a solenoid manipulator.

[0059] Item 14: A jet engine comprising: an inlet having a normal flow axis and an inner surface extending from a protrusion; a plurality of flow control devices forming at least one array integrated on the inner surface, the at least one array extending in an azimuth range relative to the normal flow axis and having a plurality of circumferential rows spaced apart from the protrusion of the inlet by an increasing axial distance; and a control system operatively connected to the plurality of flow control devices, the control system being adapted to activate the flow control devices in a selected subarray of the at least one array in response to a predetermined flight condition or inlet flow field.

[0060] Item 15. A method for flow control in a nozzle inlet, the method comprising: receiving a status signal and a mass flow signal in a controller; providing a control output from the controller to one or more of a plurality of flow control devices in an array on an inner surface of the inlet in response to the status signal and the mass flow signal; and reducing flow distortion in the inlet.

[0061] Item 16. The method of item 15, further comprising: receiving a condition signal from one or more condition sensors in a controller; wherein the step of reducing flow distortion includes modulating a plurality of flow control devices to form a subarray responsive to a mass flow signal or a condition signal to optimize the reduction of flow distortion in the inlet.

[0062] Item 17. The method of Item 16, wherein the step of modulating the plurality of flow control devices includes selectively aligning concentric cylinders with an array of holes to connect respective subarrays of the plurality of flow control devices to a pressure source.

[0063] Item 18. The method according to Item 16 or 17, wherein the step of modulating the plurality of flow control devices includes: selectively opening a valve between a pressure source and one or more of the plurality of flow control devices to form a subarray, or a pressure source and one or more manifolds connected to the subarray of the plurality of flow control devices.

[0064] Item 19. The method according to any one of items 16 to 18, wherein the plurality of flow control devices includes a synthesis device, and the step of modulating the plurality of flow control devices includes selectively activating the synthesis device to form a subarray.

[0065] Item 19. The method according to any one of items 16-19, wherein the plurality of flow control devices includes an expandable eddy current generator, and the step of modulating the plurality of flow control devices includes selectively expanding and retracting the expandable eddy current generator to form a subarray.

Claims

1. An inlet flow distortion control system, comprising: Multiple flow control devices are integrated into the inner surface of the inlet, forming a right array and a left array. The right array has an azimuth range relative to the normal flow axis of the inlet and determined based on a right-side airflow separation domain. The left array has an azimuth range relative to the normal flow axis of the inlet and determined based on a left-side airflow separation domain. Each of the right and left arrays has multiple circumferential rows spaced apart from the protrusion of the inlet by an increasing axial distance. Wherein, for each of the right array and the left array, a first row of the plurality of circumferential rows includes flow control devices extending over the azimuth range of each of the right array and the left array; a second row of the plurality of circumferential rows includes flow control devices extending over a reduced azimuth range of each of the right array and the left array; and a third row of the plurality of circumferential rows includes flow control devices extending over a further reduced azimuth range of each of the right array and the left array; and A control system operatively connected to the plurality of flow control devices, the control system being adapted to activate the flow control devices in the right array or a selected subarray of the left array in response to an inlet flow state indicated by a predetermined flight condition or flow parameters measured within the inlet.

2. The inlet flow distortion control system according to claim 1, wherein, The control system includes: The controller receives status signals or condition inputs for crosswind or angle of attack; The mass flow is input to the controller; and One or more activation devices, in response to the mass flow input and the status signal or condition input receiving an output signal from the controller, are configured to activate a flow control device in one of the selected subarrays.

3. The inlet flow distortion control system according to claim 2, wherein, The one or more activation devices include: One or more concentric cylinders spaced apart between the inner surface of the inlet and the pressure chamber, the one or more concentric cylinders having an array of holes rotatable from a closed position to be aligned with one or more control nozzle rows; and, A pressure source, which is connected to the pressure chamber.

4. The inlet flow distortion control system according to claim 3, wherein, The pressure source is the exhaust system.

5. The inlet flow distortion control system according to claim 3, wherein, The one or more concentric cylinders include a plurality of concentric cylinders, each concentric cylinder being aligned with a corresponding one of the one or more rows of control nozzles to open one of the selected subarrays into the pressure chamber.

6. The inlet flow distortion control system according to claim 2, wherein, The one or more activation devices include one or more valves, each valve being connected to a corresponding flow control device among the plurality of flow control devices.

7. The inlet flow distortion control system of claim 6, further comprising at least one manifold connecting one of the one or more valves to a selected subarray of the right array or the left array of the plurality of flow control devices.

8. The inlet flow distortion control system according to claim 2, wherein, Each of the plurality of flow control devices includes a synthesis nozzle, and further includes: The power is connected to each synthetic nozzle; and, A horizontal controller, connected to each synthesizing nozzle via a repeater, is capable of controlling the generation of a selected subarray of the right array or the left array.

9. The inlet flow distortion control system according to any one of claims 2-8, wherein, Each of the plurality of flow control devices includes an expandable eddy current generator, and each of the one or more activation devices includes a solenoid manipulator.

10. A method for flow control in a nozzle inlet, the method comprising: The controller receives status signals and mass flow signals. In response to the status signal and the mass flow signal, a control output from the controller is provided to one or more of a plurality of flow control devices in at least one array on the inner surface of the inlet, the at least one array extending in an azimuth range relative to the normal flow axis of the inlet and having a plurality of circumferential rows spaced apart from the protrusion of the inlet by an increasing axial distance, wherein a first row of the plurality of circumferential rows includes flow control devices extending in the azimuth range of the at least one left array, a second row of the plurality of circumferential rows includes flow control devices extending in a reduced azimuth range of the at least one array, and a third row of the plurality of circumferential rows includes flow control devices extending in a further reduced azimuth range of the at least one array; as well as Reduce flow distortion in the inlet.

11. The method of claim 10, further comprising: The controller receives condition signals from one or more condition sensors; wherein the step of reducing flow distortion includes... The plurality of flow control devices are modulated to form a subarray responsive to the mass flow signal or condition signal to optimize the reduction of flow distortion in the inlet.

12. The method according to claim 11, wherein, The step of modulating the plurality of flow control devices includes selectively aligning concentric cylinders with the array of holes to connect respective subarrays of the plurality of flow control devices to a pressure source.

13. The method according to claim 11, wherein, The steps of modulating the plurality of flow control devices include: Open selectively A valve between a pressure source and one or more of the plurality of flow control devices to form the subarray, or A pressure source and one or more manifolds connected to the subarray of the plurality of flow control devices.

14. The method according to claim 11, wherein, The plurality of flow control devices include a synthesis device, and the step of modulating the plurality of flow control devices includes selectively activating the synthesis device to form the subarray.

15. The method according to any one of claims 11-14, wherein, The plurality of flow control devices include an expandable eddy current generator, and the step of modulating the plurality of flow control devices includes selectively expanding and retracting the expandable eddy current generator to form the subarray.

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