Vortex generator structure for aircraft and aircraft

Abstract

The present application relates to a vortex generator structure. The vortex generator structure (115) comprises a portion (405) defining an opening (421) leading to a corresponding chamber (423), an aircraft airflow changing device (301) arranged in the chamber (423), and at least one fluid muscle actuator structure (801) coupled to the airflow changing device (301). The present application also relates to an aircraft comprising the vortex generator structure.

Description

Technical Field

[0001] The present technology relates to an aircraft airflow modification device and a vortex generator structure for an aircraft including the aircraft airflow modification device. Background Art

[0002] The vertical tail of an aircraft and the vertical rudder mounted to the vertical tail provide a method of controlling the yaw moment for rotating the aircraft around its vertical axis or yaw axis. Therefore, the vertical tail and the vertical rudder provide directional stability and directional control. The maximum yaw moment that the rudder can produce depends on the size of the rudder and the degree to which the rudder can deflect around the rudder axis. In other words, a larger yaw moment can be produced with a larger rudder or a rudder that can deflect a larger angle. Since the rudder can only deflect a limited angle to avoid the stall flow at the rudder, the maximum yaw moment is mainly determined by the overall shape and surface area of ​​the vertical tail and the rudder.

[0003] Under normal operating conditions, the maximum yaw moment is never required, so most of the yaw moment that can be generated by the vertical rudder remains unused, which causes unnecessary aerodynamic drag, and with increased drag, fuel consumption increases, thereby reducing the maximum range of the aircraft. Therefore, any unnecessary drag should be avoided.

[0004] In view of the above, it can be considered that the purpose of the present technology is to improve the flow generated by the vertical tail and the vertical rudder without having to increase the size of the vertical tail. Another purpose of the present technology is to provide a vortex generator structure that is less prone to failure or has low maintenance costs due to having few moving parts in its design. Summary of the invention

[0005] One embodiment of the present technology provides a vortex generator structure that includes a portion defining an opening to a corresponding chamber, an aircraft airflow altering device disposed within the chamber, and at least one fluid muscle actuator structure coupled to the airflow altering device.

[0006] In another embodiment of the present technology, an aircraft airflow changing device may include an elastically deformable baffle member and an elastically deformable base member, wherein, when the elastically deformable base member is in a first state, the elastically deformable baffle member of the aircraft airflow changing device in the corresponding first state extends through the opening, wherein, when the elastically deformable base member is in a second state, the elastically deformable baffle member of the aircraft airflow changing device in the corresponding second state is retracted from the opening, and wherein the fluid muscle actuator is configured to apply a force to the elastically deformable base member of the aircraft airflow changing device to deform the elastically deformable base member from the first state to the second state or to deform the elastically deformable base member from the second state to the first state.

[0007] The first state of the elastically deformable baffle member and the corresponding first state of the elastically deformable base member can be a non-flexed state. The fluid muscle actuator structure can be configured to provide a force substantially in the direction of the transverse axis of the elastically deformable base member. In another embodiment of the present technology, the fluid muscle actuator structure may also include at least one coupler configured to offset the fluid muscle actuator relative to the airflow changing device by a distance D. The distance D may preferably be about 10 mm.

[0008] In another embodiment of the present technology, the fluid muscle actuator may be configured to be pivotally connected to the coupler. The body of the coupler may be configured to extend from the airflow altering device in a generally vertical direction.

[0009] In another embodiment of the present technology, the fluid muscle actuator structure can be pneumatically driven. In another embodiment, the fluid muscle actuator structure can be hydraulically driven. The fluid muscle actuator structure can preferably be configured to operate within a pressure range of 0Pa to +600000Pa relative to ambient pressure. The fluid muscle actuator structure can preferably be configured to have an extended length of about 60mm.

[0010] In another embodiment of the present technology, the elastic strain energy stored by the fluid muscle actuator and the elastically deformable base member may be sufficient to deploy the airflow altering device. In another embodiment, the elastic strain energy stored by the fluid muscle actuator may be sufficient to deploy the airflow altering device.

[0011]

[0013] In yet another embodiment of the present technology, an aircraft having at least one vortex generator structure may be provided.

[0012] Advantages of the present technology will now become apparent from the detailed description with appropriate reference to the accompanying drawings.

[0013] Description of the drawings

[0014] Embodiments of the present technology will now be described, by way of example only, with reference to the following drawings, in which:

[0015] Figure 1 is a side view of an aircraft including a plurality of vortex generator structures and a system for operating the vortex generator structures;

[0016] Figure 2 yes Figure 1 A close-up view of the vertical tail of the aircraft of FIG. 1 showing the location of the vortex generator structure in more detail;

[0017] Figure 3A yes Figure 1 and Figure 2 An isometric view of an aircraft airflow modifying device of a vortex generator structure of the vortex generator structure in a first state of extension;

[0018] Figure 3B yes Figure 3A An isometric view of an aircraft airflow modification device in a retracted second state;

[0019] Figure 4A yes Figure 1 and Figure 2 An isometric view of a vortex generator structure of the invention, the vortex generator structure comprising an aircraft airflow changing device in a first state of extension;

[0020] Figure 4B yes Figure 3B An isometric view of the vortex generator structure in a retracted second state;

[0021] Figure 5A The vortex generator structure 115 is provided along Figure 4A A side cross-sectional view of the YZ plane indicated in ;

[0022] Figure 5B The vortex generator structure 115 is provided along Figure 4B A side cross-sectional view of the YZ plane indicated in ;

[0023] Fig. 6A yes Figure 4A The vortex generator structure is adopted Figure 4A The front cross-sectional view of the plane XZ given in ;

[0024] Figure 6B yes Figure 4B The vortex generator structure is adopted Figure 4B The front cross-sectional view of the plane XZ given in ;

[0025] Fig. 7A According to another embodiment of the present technology Figure 4AA front cross-sectional view of a vortex generator structure;

[0026] Figure 7B According to another embodiment of the present technology Figure 4B A front cross-sectional view of a vortex generator structure.

[0027] Fig. 8A and Figure 8B is a front cross-sectional view of a vortex generator structure 115 according to another embodiment of the present technology.

[0028] Fig. 9A and Fig. 9B An expansion operation of the vortex generator control system 814 and a contraction operation of the vortex generator control system 814 according to an embodiment of the present technology are respectively provided.

[0029] Fig. 10A and Fig. 10B is a front cross-sectional view of a vortex generator structure 115 in accordance with an embodiment of the present technology. DETAILED DESCRIPTION

[0030] Reference Figure 1 , the aircraft 101 includes a pair of lifting surface assemblies in the form of wings 103 joined to a fuselage 105. Each wing 103 includes hinged control surfaces such as ailerons and spoilers (not shown), and high lift devices such as flaps and slats (not shown). Each wing 103 carries an engine 107 mounted to an engine pylon 108 using the wing. The aircraft 101 includes additional lifting surface assemblies in the form of a horizontal tail 109 and a vertical tail 111, wherein the horizontal tail 109 and the vertical tail 111 are each attached to the rear of the fuselage 105. The vertical tail 111 is provided with an articulated control surface in the form of a rudder 113. The aircraft 101 includes other surface assemblies, such as a belly fairing 112 that smoothly connects the wing 103 to the fuselage 105, and a high lift device fairing 114 that smoothly connects each portion of the flap (not shown) to the corresponding wing 103.

[0031] In this embodiment, the aircraft 101 also includes a plurality of vortex generator structures 115 installed in the vertical tail 111. The deflection of each control surface and the deflection of each vortex generator structure 115 are controlled by at least one flight control unit 117. The flight control unit 117 receives input from at least one sensor unit 119 and commands the deflection according to a predetermined flight envelope stored on a medium (not shown) connected to the flight control unit 117.

[0032] Reference Figure 2In this embodiment, each vortex generator structure 115 is set separately from the adjacent vortex generator structure 115 along the span direction of the vertical tail 111. Each vortex generator structure 115 is installed in the main body 203 of the vertical tail 111 and has a chordwise position set in front of the leading edge 201 of the rudder 113.

[0033] Reference Figure 3A In this embodiment, an aircraft airflow altering device 301 is provided, comprising an elastically deformable baffle member 303 laminated to an elastically deformable base member 305 to form a single integrally formed component, i.e., the component has no hinges or separate connector elements. In a first state, the elastically deformable baffle member 303 is generally flat and rectangular in shape and extends in the YZ plane in a manner generally perpendicular to the elastically deformable base member 305 also in the corresponding first state, such that the most lateral edge 307 of the elastically deformable baffle member 303 is generally coincident with the YZ plane.

[0034] The elastically deformable baffle member 303 is formed of 8 layers of co-cured GFRP laminate material that steps down from 8 layers to 4 layers at the edge 307 of the elastically deformable baffle member 303. Each layer may use an epoxy / E-glass composite material.

[0035] The elastically deformable baffle member 303 may have a dimension Hf of at least 10 mm in the Z direction, but preferably, it has a dimension Hf of 20 mm in the Z direction. The elastically deformable baffle member 303 may have a dimension Wf of at least 30 mm in the Y direction, but preferably, it has a dimension Wf of 60 mm in the Z direction. The elastically deformable baffle member 303 may have a dimension Tf of at least 0.5 mm in the X direction, but preferably, it has a dimension Tf of 1 mm in the X direction.

[0036] The elastically deformable base member 305 is formed of a rectangular GFRP laminate profile, so that the elastically deformable apron member 303 has a relatively low lateral stiffness when compared to the elastically deformable base member 305 .

[0037] The elastically deformable base member 305 may have a dimension Hb of at least 2 mm in the Z direction, but preferably it has a dimension Hb of 5 mm in the Z direction.

[0038] The elastically deformable base member 305 has a dimension Wb in the Y direction of at least 60 mm (ie, the same Y dimension as the elastically deformable baffle member 303), but preferably it has a dimension Wb in the Y direction of 80 mm.

[0039] The elastically deformable base member 305 preferably has a dimension Tb of 20 mm in the X direction.

[0040] Alternatively, the elastically deformable baffle member 303 or the elastically deformable base member 305 may be formed of any other suitable material and also by any suitable method, such as non-metallic materials, metallic materials or composite materials, including but not limited to laying and curing materials, manufacturing by adding layers, or by machining, forming, casting or molding materials. In addition, the elastically deformable baffle member 303 and the elastically deformable base member 305 may be formed integrally.

[0041] In addition, the elastically deformable baffle member 303 may not be rectangular in shape, but may have a swept leading edge or trailing edge. Alternatively, the elastically deformable baffle member 303 may be triangular. Alternatively, the elastically deformable baffle member 303 may include a curved edge. Alternatively, the elastically deformable baffle member 303 may be semicircular or semi-elliptical.

[0042] is shown as being in Figure 3A The aircraft airflow changing device 301 in the first state is Figure 3B 305 is shown in the second state. In response to the positive bending moment Mx about the X-axis, the elastically deformable base member 305 undergoes uniaxial elastic bending to reach the second state, thereby causing asymmetric elastic buckling of the elastically deformable baffle member 303 to reach the corresponding second state. This is caused by the lateral torsional buckling of the elastically deformable baffle member 303 having a lower total lateral stiffness than the total lateral stiffness of the elastically deformable base member 305. When the elastically deformable baffle member 303 is in the second state, its lateralmost edge 307 is at a substantially perpendicular angle A relative to the YZ plane.

[0043] Removing the bending moment Mx from the elastically deformable base member 305 (i.e., causing the elastically deformable base member 305 to return from the second state to the first state) causes the elastically deformable baffle member 303 and the elastically deformable base member 305 to elastically deform back to their respective non-bent first states, wherein the outermost edge 307 of the elastically deformable baffle member 303 returns to a position that substantially coincides with the YZ plane, and the elastically deformable base member 305 is substantially rectangular in shape.

[0044] In the present embodiment, the elastically deformable baffle member 303 is in an extended configuration when the first state is a non-flexed state, and is in a contracted configuration when the second state is a flexed state. Correspondingly, the elastically deformable base member 305 is non-flexed in the first state and is flexed in the corresponding second state. However, it should be understood that those skilled in the art will understand that different variations can be achieved, for example, the aircraft airflow change device can be constructed and manufactured so that the elastically deformable baffle member 303 is extended and non-flexed in the first state corresponding to the flexed first state of the elastically deformable base member 305.

[0045] Reference Figure 4A In this embodiment, each vortex generator structure 115 includes a shell 401 that is generally rectangular in shape overall; having an outer cover 403 defined by a portion 405 that is generally coplanar with the outermost surface (also commonly referred to as the outer mold line or OML) of the vertical tail 111 (not shown). It should be understood that the exact shape of the shell 401 may be determined by the available space in which it is to be installed, so the shell 401 may not be rectangular in shape. The shell 401 includes a front wall 407, a rear wall 409, a pair of side walls 411, 413, and an innermost wall 414 (not shown), the front wall 407 and the rear wall 409 are each arranged to be generally parallel to the XZ plane, the pair of side walls 411, 413 are each arranged to be generally parallel to the YZ plane, and the innermost wall 414 is arranged to be generally parallel to the XY plane and offset from the outer cover 403. The shell 401 is a unitary component formed of CFRP material. However, the housing 401 may be an assembly of two or more separate subcomponents formed of the same material, the subcomponents being attached to each other by any suitable means, such as by replaceable fasteners. Such a structure may be preferred for subsequent assembly and disassembly of the vortex generator structure 115. The housing 401 may also be formed of any other suitable non-metallic material, metallic material, or composite material and using any suitable manufacturing method, such as additive layer manufacturing, machining, forming, casting, molding, or lay-up and curing.

[0046] Peripheral edge 417 of outer cover 403 is configured to extend generally perpendicular to walls 407 , 409 , 411 , 413 of shell 401 so as to define an overhang 419 configured to attach to a corresponding peripheral edge 501 (not shown) provided by vertical fin 111 .

[0047] The overhang 419 extends substantially along the entire peripheral edge 417, i.e. along the front wall 407, the rear wall 409 and the two side walls 411, 413 of the vortex generator structure 115. However, this overlapping structure may be discontinuous around the peripheral edge of the top cover 403. In this embodiment, countersunk quick release fasteners (not shown) are used in combination with corresponding nut plates (not shown) attached to the respective parts of the surrounding structure to assemble the vortex generator structure 115 to the vertical tail 111. This provides a line replaceable system, which is important for in-service operations, where a failed unit can be quickly replaced to prevent unnecessary delays during normal operation. Alternatively, the vortex generator structure 115 can form an integral part of the vertical tail 111, i.e. part of the cover of the vertical tail 111.

[0048] Portion 405 also defines an opening 421 in outer cover 403 of housing 401 to a corresponding chamber 423 within housing 401, wherein chamber 423 is also defined by the inner surfaces of walls 407, 409, 411, and 413. The inner surfaces may be offset as shown, or may be in close proximity to the edge of elastically deformable baffle member 303. The edge of opening 421 may include a large radius or chamfer configured to improve airflow through chamber 423.

[0049] The chamber 423 is provided with an aircraft airflow changing device 301, which is supported by the front wall 407 and the rear wall 409 of the housing 401 and includes an elastically deformable baffle member 303. Figure 4A In the first state shown in FIG. 4 , the PCB extends through the opening 421 .

[0050] When the elastically deformable baffle member 303 is extended in the first state during operation of the aircraft 101, a portion of the airflow 431 proximate the outer cover 403 is changed by the elastically deformable baffle member 303 to generate one or more airflow vortices 433 that flow rearward from the location of the vortex generator structure 115 and flow through the vertical tail 111 and the rudder 113.

[0051] Reference Figure 4B , Figure 4A The vortex generator structure 115 is shown in a second configuration in which the elastically deformable baffle member 303 of the aircraft airflow modification device 301 is in its second flexed state and the elastically deformable base member is in a corresponding second flexed state, i.e. corresponding to Figure 3B The state shown in FIG. 4 is when it is retracted from the opening 421 .

[0052] The known effect of vortices 433 near a lifting surface that is subject to airflow separation is that even though such vortices 433 also generate relevant amounts of form drag and vortex drag, the onset of separation of the airflow from the lifting surface is still delayed. Despite this drag loss, vortices 433 are still desirable in certain situations. For example, the vertical tail 111 or the rudder 113 are dimensioned taking into account parameters such as surface area, airfoil cross section, so that when the vertical tail 111 and the rudder 113 are operated at the maximum angle of incidence relative to the airflow direction of the free stream, they can provide sufficient yaw moment to control the aircraft 101. The dimensions of the vertical tail 111 and the rudder 113 for these situations can take into account a certain amount of lift loss caused by possible flow separation. Therefore, in the context of the present embodiment of the vertical tail 111 or rudder 113, when the vortex 433 is introduced in front of (upstream of) the area of ​​the vertical tail 111 and rudder 113, the flow separation loss can be reduced or completely eliminated, otherwise the flow separation will be presented at a larger angle of incidence. The vortex generator structure 115 of the present technology is a device to achieve this, and the vortex generator structure 115 further allows the overall size of the vertical tail 111 and rudder 113 to be reduced and the overall weight is therefore reduced, which is advantageous in terms of the manufacturing and operating costs of the aircraft 101.

[0053] Reference Figure 4B , contraction of the elastically deformable baffle member 303 restores the airflow near the vortex generator structure 115 to its nominal characteristics and avoids form drag and vortex drag losses that would otherwise occur. This configuration is desirable, for example, when the vertical tail 111 or rudder 113 does not need to operate at a high angle of incidence relative to the free stream airflow direction during cruise. In this embodiment, the opening 423 can also be provided with a thin rupturable membrane configured to extend over the opening 423 in the plane of the portion 405 and fastened or bonded to the outer cover 403. The rupturable membrane will provide aerodynamic coverage for the chamber 423, but is also configured to be permanently ruptured due to the elastically deformable baffle member 303 contacting the rupturable membrane during the initial stage of its first extension, so as not to inhibit the full extension or performance of the elastically deformable baffle member 303.

[0054] However, it should be understood that it is preferred that when the elastically deformable baffle member 303 of the airflow altering device 301 is in the second flexed state and the elastically deformable base member is in the corresponding second flexed state, the elastically deformable baffle member 303 of the airflow altering device 301 is not fully retracted into the chamber but rather it is positioned substantially parallel to the plane of the portion 405. In this configuration, the elastically deformable baffle member 303 in the retracted second state will remain in the airflow but will not generate any significant vortices 433 and associated drag. However, it may generate a certain degree of acceptable form drag.

[0055] Another advantage of using a vortex generator structure 115 comprising such an aircraft airflow modification device 301 is that the aircraft airflow modification device 301 has no moving parts, so that its design is simplified. Therefore, it may also have a lower probability of failure due to wear or due to seizure in the presence of contaminants such as ice, oil or dust, etc. This may result in a smaller number of vortex generator structures 115 being required and thus reducing costs or complexity due to longer maintenance inspection intervals.

[0056] It should also be understood that one or more vortex generator structures 115 can be arranged at other locations on the vertical tail 111 - for example, at the forward "leading" edge portion of the vertical tail 111 or the rudder 113 - in order to enhance aerodynamic performance. It should also be understood that the one or more vortex generator structures 115 can be arranged at other locations on the aircraft 101 near any other lifting surface where it may be desirable to inhibit flow separation. For example, the one or more vortex generator structures 115 can be installed at a portion of the forward or rearward "trailing" edge of the wing 103 or horizontal tail 109. Alternatively, the one or more vortex generator structures 115 can be installed on another surface component such as the pylon 108 or the engine 107. In addition, the one or more vortex generator structures 115 can be used to improve the aeroacoustic performance of the aircraft 101. For example, one or more vortex generator structures 115 may be positioned forward of (upstream of) and proximate to an opening 110 defined by a portion of an exterior surface of the vehicle 101 to generate one or more vortices 433 that may reduce audible Helm-Holtz induced frequencies from such opening 110 .

[0057] Reference Figure 5A , the airflow changing device 301 is installed in the chamber 423. The first end 502 and the second end 503 of the elastically deformable base member 305 are each positioned in the corresponding grooves 509 and 507 defined by the rear wall 409 and the front wall 407, respectively, so that the airflow changing device 301 is supported at both ends. An actuator structure 510 and a connector 513 including an electric linear actuator 511 are also installed in the chamber 423. It should be understood that the actuator structure can include any suitable alternative actuator, such as a rotary actuator or a piezoelectric actuator. The actuator can be alternatively hydraulically excited. The first end 515 of the linear actuator 511 has a lug and is pivotally mounted to a corresponding set of lugs provided by the innermost wall 414 of the chamber 423 with a U-shaped clip pin 519.

[0058] The second end 521 of the linear actuator 511 includes lugs pivotably connected to a set of lugs provided by the coupler 513 via another clevis pin 523. A coupler 525 is fixedly attached to a lower surface 527 of the elastically deformable base member 305 at approximately mid-length in the Y direction thereof.

[0059] Instead of either the pin structure or the coupler 525 used to connect the linear actuator 511 to the housing 401 , a universal ball joint type structure that may allow for greater degrees of freedom may alternatively be used, as desired.

[0060] When the actuator structure 510 is in the Figure 5A , the elastically deformable base member 305 is in a first state which is a non-bent state, and the elastically deformable baffle member 303 is therefore in a corresponding first state which is also non-bent. In this state, the elastically deformable baffle member 303 extends through the opening 421 and acts as a vortex generator in the presence of airflow passing through the vertical tail 111.

[0061] Reference Figure 5B , showing Figure 5A All the characteristics of Figure 5B 4, the actuator structure 510 is actuated to the second position, thereby providing a force generally along the vertical axis of the elastically deformable base member 305, causing the elastically deformable base member 305 to deform to the second state of the flexed state and the elastically deformable baffle member 303 to also deform to the corresponding second state of the flexed state. In this state, the elastically deformable baffle member 303 is retracted from the opening 421, causing the elastically deformable baffle member 303 to extend generally in the plane of the portion 405 (i.e., in the plane of the OML), so that the airflow near the opening 421 is not substantially changed. By removing the vertical force applied by the actuator structure 510, such as by deactivating the linear actuator 511, the elastic energy stored in the aircraft airflow change device 301 is sufficient to drive the linear actuator 511 in the opposite direction to restore the aircraft airflow change device 301 from the flexed second state to the non-flexed first state. No power or command needs to be supplied to the linear actuator 511 to extend the elastically deformable baffle member 303, which is advantageous because the design is inherently fail-safe and ensures that the maximum yaw moment capability of the vertical tail 111 and rudder 113 is still available as required when no power is present, albeit in exchange for minimal drag penalties.

[0062] It will be appreciated that the aircraft airflow changing device 301 may alternatively be actuated and deformed between the first and second states by deformation of surrounding structure acting on the elastically deformable base member 305 or by a pressure differential acting on the elastically deformable baffle member 303 due to airflow outside the chamber rather than by actuation of the specific type of powered actuator structure described thus far.

[0063] Reference Fig. 6A and Figure 6B , a gap 601 is provided between the side wall 413 of the housing 401 and the airflow changing device 301. Such a gap 601 may be preferred for providing a path for installing or replacing the actuator structure 510 or other internal components within the housing 401 or for performing maintenance or repair inspections. It should be understood that such a gap 601 may not be required, but the side wall 413 of the housing 401 may be configured so that when the elastically deformable base member 305 is in the first state and the second state, the side edge 309 of the elastically deformable base member 305 generally abuts the inner surface of the side wall 413, and the side wall 413 of the housing 401 may also be configured to generally abut the side edge 307 of the elastically deformable baffle member 303 when the elastically deformable baffle member 303 is in the second state of flexion. This may be preferably done to prevent liquid, contaminants from collecting in the chamber 423.

[0064] The coupler 513 is also shown to span substantially across the elastically deformable base member 305 in the X direction. This ensures that loads applied vertically by the actuator structure 510 in the Z direction are evenly distributed across the X dimension of the elastically deformable base member 305 via the coupler 513. Attaching the linear actuator 511 to the coupler 513 at the second end using a pivoting clevis pin 523 may allow for easier installation and replacement of the linear actuator 511 when required. The use of pivoting connections 519 and 523 in the actuator structure 510 ensures that bending loads are not applied to the elastically deformable base member 305 when vertical loads are applied, which bending loads may cause unintended deformation of the aircraft airflow altering device 303.

[0065] Reference Fig. 7A , shows an alternative embodiment. The vortex generator structure 115 of this embodiment is Figure 4A The vortex generator structure 115 shown in FIG. 1 is substantially the same.

[0066] An airflow altering device 301 is mounted within the chamber 423. The elastically deformable base member 305 of the device is formed so that in its first non-flexed state it is in a generally slightly curved shape in the positive Z direction, represented in the figure by the dashed line 701 and the upper and lower surfaces 702. The first end 709 of the elastically deformable base member 305 is circular in shape and is positioned in a corresponding first slot 509 also having a corresponding circular shape, so that the first end 709 substantially conforms to the inner surface of the first slot 509.

[0067] The second end 707 of the elastically deformable base member 305 is positioned in a corresponding second slot 507 of similar corresponding shape. An actuator structure 710 is arranged in the second slot 507. The actuator structure comprises a linear actuator 711. The linear actuator 711 is fixed to the frontmost wall 407 of the housing 401 at a first end 713.

[0068] The second end 715 of the linear actuator 711 is pivotally attached to the second end 707 of the elastically deformable base member 305 by a clevis pin 717. The actuator structure 710 allows the elastically deformable base member 305 to rotate relative to the second end 715 of the linear actuator 711 and in a manner generally parallel to the YZ plane.

[0069] When the actuator structure 710 is in the Fig. 7A , the elastically deformable base member 305 is in a first state which is a non-bent state, and the elastically deformable baffle member 303 is therefore in a corresponding first state which is also non-bent. In this state, the elastically deformable baffle member 303 extends through the opening 421 and acts as a vortex generator in the presence of airflow passing through the vertical tail 111.

[0070] Reference Figure 7B , showing Fig. 7A All the characteristics of Figure 7B4, the actuator structure 710 is actuated to the second position, thereby providing a force generally along the transverse axis (Y direction) of the elastically deformable base member 305, causing the elastically deformable base member 305 to deform to the second state of the flexed state and the elastically deformable baffle member 303 to also deform to the corresponding second state of the flexed state. In this state, the elastically deformable baffle member 303 is retracted from the opening 421, causing the elastically deformable baffle member 303 to extend generally in the plane of the portion 405 (i.e., in the plane of the OML), so that the airflow near the opening 421 is not substantially changed. By removing the transverse force applied by the actuator structure 710, such as by deactivating the linear actuator 711, the elastic energy stored in the aircraft airflow change device 301 is sufficient to drive the linear actuator 711 in the opposite direction to restore the aircraft airflow change device 301 from the flexed second state to the non-flexed first state.

[0071] When with Figure 5A , Figure 5B , Fig. 6A and Figure 6B When compared to the embodiment of FIG. 1 , it can be seen that the housing 401 in this embodiment does not need to have such a large chamber 423 due to the actuator structure 710 requiring a much shorter stroke to achieve the same amount of deformation of the aircraft airflow changing device 301. Piezoelectric actuators may be preferred for this structure due to their relatively high power density for a given size. As a result, the inner wall 414 of the housing 401 is closer to the outer wall 403 and is therefore shallower, making the vortex generator structure 115 of this embodiment much more compact. This structure may be preferred where the available internal space of the vertical tail 111 is limited, and may be particularly desirable for the outer trailing edge region or other lifting surfaces of the vertical tail 111.

[0072] Reference Fig. 8A , showing an embodiment of the vortex generator structure 115. An airflow altering device 301 is mounted within the chamber 423, shown in a first position. The elastically deformable base member 305 of the device 301 is again formed so that in its non-flexed first state, it has an overall slightly curved shape in the positive Z direction, represented in the figure by the dashed line 701 and the upper and lower surfaces 702. A first end 709 of the elastically deformable base member 305 is positioned within a corresponding first slot 509 of similar corresponding shape. A second end 707 of the elastically deformable base member 305 is positioned within a corresponding second slot 507 of similar corresponding shape. Each end 707, 709 may have a shape corresponding to the housing 401, for example each end may be rounded to allow the airflow altering device 301 to be rotated more easily.

[0073] A fluid muscle actuator structure 801 is provided, which includes a fluid muscle actuator 803 pivotally connected to a pair of couplers 805; there is a coupler 805 at each end of the actuator 803. Each coupler 805 extends in a generally vertical direction from a lower portion of the airflow changing device 301 at a first end 709 and a second end 707 adjacent to the slots 509 and 507. Alternatively, the coupler may extend from the base member 305 at an acute angle, however, this may increase the width of the chamber 423 and therefore increase the overall size of the vortex generator structure 115. The coupler has a substantially L-shaped body formed of CFRP and bonded to the lower surface 702 of the base member 305 at an upper surface. Alternatively, any other suitable material may be selected, such as CRESS. In addition, it may be preferred that one or more couplers are integrally formed from the same material as the airflow changing device 301.

[0074] The opposite end of each coupler forms a U-shaped clip 811, which is configured to receive a corresponding lug 813 and a pin 809. When the lug 813 formed by the body of the fluid muscle actuator 803 is received in the corresponding U-shaped clip 811 and fixed at each coupler 805 using the pin 809, a pivotable connection between the fluid muscle actuator 803 and the coupler 805 is achieved. The coupler 805 is used to support the fluid muscle actuator 803 in the chamber 423 and offset the fluid muscle actuator 803 relative to the base member 305 or the baffle member 303 of the airflow changing device 301 by an offset length D, and the offset length D is between 5 mm and 15 mm in length. Preferably, 10 mm is used.

[0075] The use of a coupling 805 that provides an offset of length D as shown is advantageous because a moment arm of substantially the same length is introduced between the base member 305 and the load application point of the actuator 803, so that a higher positive bending moment or negative bending moment Mx about the X axis can be achieved for a given size of fluid muscle actuator 803. This can allow the use of smaller fluid muscle actuators 803 in some cases, which reduces the cost, power consumption and weight of the entire vortex generator structure 115. The pivotable connection of the coupling 805 optimizes the direction of the load from the actuator 803 and ensures that the fluid muscle actuator 803 itself is not subjected to bending or torsional loads caused by its own actuation. However, it should be understood that, alternatively, the fluid muscle actuator 803 can be directly attached to the elastically deformable base member 305 or the elastically deformable baffle member 303 without the need for a coupling 805. In an alternative embodiment, the actuator 803 can also be non-pivotally connected to the coupling 805. Another function of the coupler 805 is to orient the actuator 803 substantially parallel to the line 701 when the airflow altering device 301 is in the first position.

[0076] The fluid muscle actuator 803 is similar to, for example, a commercially available artificial muscle type actuator from Festo Vertrieb GmbH. The actuator 803 in this embodiment is configured to be pneumatically driven by a gas pressure source supplied within an operating pressure range of 0 Pascal to +600,000 Pascal relative to the ambient atmospheric pressure value. In this embodiment, the ambient atmospheric pressure value can be within the range of values ​​determined according to the operating envelope of the aircraft, taking into account changes in air pressure and temperature according to the altitude of the aircraft and weather conditions. The pressure source can be provided by an independent pump, a pressurized or non-pressurized reservoir, or any combination of the two, such as an aircraft bleed air system or a central hydraulic system. In the case of providing power for the aircraft vortex generator structure 115, a pneumatic fluid muscle actuator 803 is desired, and pneumatic power systems tend to be lighter in weight. However, depending on the desired operating characteristics, the fluid muscle actuator 803 can alternatively be powered or hydraulically driven by any other suitable fluid. A hydraulically driven fluid muscle actuator 803 may be preferred because hydraulic systems have higher power density available and less variation in power characteristics due to ambient air temperature.

[0077] The fluid muscle actuator 803 includes an elongated body provided with a closed fluid bladder 804 having a substantially constant cylindrical cross-section over its length. At each end, the bladder 804 forms a lug 813, which, as previously described, can be attached to a U-shaped clip 811 at each end. The bladder 804 is formed of an elastic, impermeable material reinforced with a braided material, such as a rubber bladder 804 reinforced by a braided glass material. It will be appreciated by those skilled in the art that the configuration, material selection, and tightness of the reinforcing braid within the bladder 804 can be selected to determine the specific elastic strain energy, deflection characteristics, and / or force requirements of the bladder 804.

[0078] The fluid muscle actuator 803 is connected to a vortex generator control system 814 via a fluid conduit 815, and the vortex generator control system 814 includes at least one fluid pressure sensor 817, at least one solenoid-operated control valve 819, at least one pump 821, at least one reservoir 823, at least one controller 825 including a combined signal processor and memory unit 827, and the flight control unit 117, all of which are located and connected downstream of the fluid muscle actuator 803. The advantage of the vortex generator control system 814 as described above is that it is relatively simple and is formed by reliable components. Additional pressure sensors or other components may be installed in the control system 814 to achieve higher reliability and thus redundancy of the control system 814. For example, an additional control valve 819 may be installed in parallel with the first pressure control valve 819 to ensure that the failure of any valve 819 will not cause the system 814 to become inoperable. It should be understood that such a vortex generator control system 814 may be applied to the vortex generator structure 115 of any of the aforementioned embodiments, which may be provided with a hydraulically driven actuator, such as a linear hydraulic actuator, and may not necessarily require a fluid muscle actuator 803 .

[0079] When the fluid muscle actuator structure 801 is in a Fig. 8A , the elastically deformable base member 305 is in a first state which is a non-bent state, and therefore the elastically deformable baffle member 303 is in a corresponding first state which is also non-bent. In this state, the elastically deformable baffle member 303 extends through the opening 421 and acts as a vortex generator in the presence of an airflow flowing through the vertical tail 111. In addition, in this current state, the fluid muscle actuator 803 loses energy, that is, the capsule 804 of the actuator 803 has no elastic strain, and the fluid pressure in the actuator 803 is at or below the threshold value P1, which in this embodiment is 0 bar relative to the ambient atmospheric pressure. At the pressure P1, i.e. in the state of losing energy, the actuator 803 is designed to have a length L1 substantially equal to 60 mm, but depending on the size of the airflow changing device 301, the length L1 can be less than 60 mm or up to 150 mm.

[0080] If the fluid pressure in the bladder 804 increases above the threshold, the deformation (and therefore the elastic strain) of the actuator 803 increases in a manner substantially proportional to the increase in pressure. In this case, the outer diameter of the cylindrical bladder 804 begins to increase as the strain energy increases, and the elastic strain energy stored by the bladder 804 increases, and overall, the length of the actuator 803 decreases. At the peak energizing pressure P2, which in this embodiment is approximately 600,000 Pascals above the threshold, the actuator 803 is designed to have a length L2 equal to approximately 45 mm, which is approximately 25% shorter than L1. In this state, it can be said that the fluid muscle actuator 803 is shortened, and the airflow changing device 301 will be in a second state of flexion, and the airflow changing device 301 is retracted from the opening 421, as will be described later. Figure 8B The support is described in further detail below.

[0081] The opposite of this behavior exists when the actuator 803 loses energy to go from peak pressure P2 to P1. This is advantageous in the context of the aircraft vortex generator structure 115 because the entire system has an enhanced fail-safe design. If an unexpected leak in the bladder 804 of the actuator 803 or the vortex generator control system 814 causes a continued drop in pressure, the fluid muscle actuator 803 returns to its original length L1, resulting in the deployed state of the vortex generator structure 115 (generating vortices).

[0082] It should be understood that one or more vortex generator structures 115 can be connected to a single vortex generator control system 814. This is advantageous because in the event of a failure just described, since the pressure of the entire system will be affected, the risk of asymmetric deployment of multiple vortex generator structures 115 will be avoided, which may otherwise introduce undesirable aircraft handling qualities. It should also be understood that multiple vortex generator control systems 814 can be connected to multiple vortex generator structures 115, thereby obtaining a higher level of redundancy.

[0083] At least a portion of the fluid conduit 815 within the chamber 423 is elastically deformable so that it is not damaged by movement of the fluid muscle actuator 803 within the chamber 423. The conduit 815 passes through a hole formed by the housing 401. The fluid muscle actuator controller 825 controls the actuation of the fluid muscle actuator 803 (and causes actuation of the aircraft airflow modification device 301 from a flexed state to a non-flexed state). The controller 825 includes a combined signal processor and memory unit 827, which is configured to (i) receive an expansion or contraction command signal from the flight control unit 117 (ii) receive a pressure reading signal from the pressure sensor 817, and (iii) receive status signals from the valve 819 (open / closed) and the pump (energized / de-energized) 821.

[0084] The controller 825 is also configured to (i) determine the deployment or contraction state of the fluid muscle actuator 803, (ii) send such state to the flight control unit 117, (iii) send a command to the control valve 819 to open or close it, and (iv) send a command to the pump 821 to start it and pump fluid from the reservoir 823 into the actuator 803, or to stop the pump 821 and allow fluid to return from the actuator 803 to the reservoir 823.

[0085] Reference Figure 8B , which shows Fig. 8A All the characteristics of Figure 8B , the fluid muscle actuator device 801 is actuated to the second position so that a force is provided substantially along the transverse axis (Y direction) of the elastically deformable base member 305 deformed to the second state. The elastically deformable base member 305 in the second state is in a flexed state, and the elastically deformable baffle member 303 is thus also deformed into a corresponding second state in a flexed state. As shown in the second state, the elastically deformable baffle member 303 is retracted from the opening 421 so that the elastically deformable baffle member 303 is substantially stretched in the plane of the portion 405 (i.e., in the plane of the OML), so that the airflow near the opening 421 is not substantially changed.

[0086] Reference Fig. 9A , showing a method for changing the airflow changing device 301 from Fig. 8A The first position shown in FIG. Figure 8B The operation 901 comprises the following steps: 903-the flight control unit 117 sends a signal to the controller 825 to move the airflow changing device 301, 905-the controller 825 sends a signal to the valve 819 to open it, sends a signal to the pump 821 to supply energy to it and upon receiving the signal, pumps the fluid into the bag 804 of the actuator 803 through the conduit 815, so that the elastically deformable baffle member 303 of the airflow changing device 301 moves toward the retracted position, and 907-when the controller 825 receives the peak P2 pressure value detected by the pressure sensor 817, the controller 825 sends a signal to the control valve 819 to close it and sends a signal to the pump 821 to lose energy. As before, once peak pressure P2 is reached, actuator 803 has length L2, elastically deformable baffle member 303 of airflow altering device 301 also retracts from opening 421 , and maximum strain energy is stored in the now deformed walls of bladder 804 and elastically deformable base member 305 .

[0087] Reference Fig. 9B , showing a method for changing the airflow changing device 301 from Figure 8B The second position shown in FIG. Fig. 8A 909 of the deployment operation of the first position in the airflow changing device 301. Operation 909 includes the following steps: 911-the flight control unit 117 sends a signal to the controller 825 to retract the airflow changing device 301; 913-the controller 825 sends a signal to the valve 819 to open upon receiving the signal, causing the pressure in the bag 804 to drop from the peak energizing pressure P2, thereby moving the elastically deformable baffle member 303 of the airflow changing device 301 toward the deployed position; and 915-when the controller 825 receives the threshold P1 pressure value detected by the pressure sensor 817, the controller 825 sends a signal to the control valve 819 to close. As previously described, once P1 is reached, the actuator 803 has a length L1, and the elastically deformable baffle member 303 of the airflow changing device 301 extends through the opening 421 and acts as a vortex generator in the presence of airflow flowing through the vertical tail 111.

[0088] In this embodiment, the elastic strain energy stored in the walls of the bladder 804 of the actuator 803 and the elastically deformable base member 305 of the airflow changing device 301 is sufficient to cause the airflow changing device 301 to deploy and force the fluid to flow back to the reservoir 823 through the conduit 815 without the need to energize the pump 819 in the opposite direction, however, this principle can be used when necessary. Once the threshold pressure P1 is reached at the sensor 817, the controller 827 signals the valve 819 to close. The controller 825 can also send a signal to the flight control unit 117 that the deployment state has been achieved. The controller 827 can signal the valve 819 at a value slightly higher than the threshold pressure P1 to take into account any processing or signal lag in the controller 825.

[0089] The vortex generator structure 115 is configured such that the elastic strain energy stored in the actuator 803 and the elastically deformable base member 305 work together to provide the elastic strain energy required to deploy the airflow modification device 301, wherein the pressure within the actuator 803 is released, either intentionally or as a result of the vortex generator structure 115 becoming inoperable due to an accidental leak of fluid from the system 814 or the actuator 803. Alternatively, the elastic strain energy stored in the fluid muscle actuator 803 can be configured to provide the energy required to deploy the airflow modification device 301.

[0090] Although Fig. 8A and Figure 8BThe fluid muscle actuator structure 801 in the embodiment is connected to the deformable type airflow changing device 301, but the fluid muscle actuator structure 801 can also be applied to actuate the vortex generator structure 115 using the rigid type airflow changing device 901, which only includes the rigid baffle member 303, which can be carried in the chamber 423 or hingedly installed in the chamber 423. By way of example, Fig. 10A Such a structure is shown which is substantially in accordance with the previous embodiment, but wherein the airflow altering device 301 is a rigid carbon fiber baffle member 301 which is hingedly mounted and pivoted about an axis 1003 formed by a pair of concentrically aligned corrosion resistant stainless steel shafts 1001 which each engage a respective side of the member 301 and housing 401. In the present embodiment shown, the fluid muscle actuator structure 801 is configured to extend and shorten along the ZX plane substantially in the Z axis direction. The fluid muscle actuator 803 is coupled to the housing 401 at a first end by a first pivotable coupling 805 provided by a lug, pin and clevis, and is coupled to the airflow altering device 301 at a second end by a second pivotable coupling 805 also provided by a lug, pin and clevis. The pivot axis provided by the pin of the second connector 805 is offset a distance relative to the axis 1003 so that a lever arm is provided, and extension and retraction of the fluid muscle actuator 803 enables actuated rotation of the airflow altering device 301 about the axis 1003. In response to a deployment command from the flight control unit 117, the vortex generator control system 814 has commanded the vortex generator structure 115 to move to a first state, whereby the fluid muscle actuator 803 is de-energized to a threshold pressure P1 and extended to a length L1, and the airflow altering device 301 is rotated about the axis 1003 to deploy into the airflow outside the opening 421, as shown.

[0091] Fig. 10B Shown with Fig. 10A The same structure, wherein, in response to a retraction command from the flight control unit 117, the vortex generator control system 814 has commanded the vortex generator structure 115 to move to the second state, whereby the fluid muscle actuator 803 is energized to a peak pressure P2 and shortened to a length L2, and the airflow altering device 301 is rotated about the axis 1003 to retract to a position inside the cavity 423 away from the airflow. This embodiment is also a fail-safe design, wherein the elastic strain energy stored in the fluid muscle actuator 803 is configured to be sufficient to deploy the airflow altering device 301, whether it is a commanded operation or in response to an unexpected pressure loss in the vortex generator control system 814 or the actuator 803.

[0092] Using Fluid Muscle Actuator 803 FIG. 8A to FIG. 10B Embodiments of the invention may be preferred because the use of the fluid muscle actuator 803 enables elastic strain energy to be stored by the actuator 803, which stored elastic strain energy can then be used additionally or entirely for fail-safe deployment of the airflow altering device 301. In certain embodiments, this may also allow for a reduction in the elastic energy required to be stored by the base member 305, allowing for the use of a less rigid and therefore smaller or lighter base member 305. This allows for more space to be available within the chamber 423 for the actuation structure 801, potentially allowing for the use of a higher power actuator, or alternatively for the use of a more compact vortex generator structure 115, which is advantageous for the reasons previously described. Additionally, the use of the fluid muscle actuator 803 is advantageous because they have a higher strength to weight ratio than conventional electric motors and hydraulic linear actuators, allowing for a reduction in the weight of the vortex generator structure 115. This is advantageous in aerospace, where the weight of the flight component is an important design requirement. Finally, the vortex generator structure 115 including the fluid muscle actuator structure 801 includes fewer moving parts and a substantially non-metallic configuration, which makes the design less susceptible to wear, corrosion, and clogging by contaminants such as water, ice, hydraulic oil, and / or dust.

[0093] Where in the foregoing description it is mentioned that an integral part or element has known, obvious or foreseeable equivalents, then these equivalents are incorporated herein as if set forth individually. Reference should be made to the claims to determine the true scope of the invention, which should be construed to include any such equivalents. The reader will also understand that integral components or features of the invention described as preferred, advantageous, convenient, etc. are optional and do not limit the scope of the independent claims. Furthermore, it should be understood that such optional integral parts or features, while potentially beneficial in some embodiments of the invention, may not be desirable in other embodiments and therefore may not be present.

Claims

1. A vortex generator structure (115), comprising: a portion (405) defining an opening (421) leading to a corresponding chamber (423); an aircraft airflow changing device (301), the aircraft airflow changing device (301) being arranged in the chamber (423); and At least one fluid muscle actuator structure (801), the at least one fluid muscle actuator structure (801) being coupled to the airflow changing device (301), wherein the aircraft airflow changing device (301) comprises an elastically deformable baffle member (303) and an elastically deformable base member (305), wherein when the elastically deformable base member (305) is in a first state, the elastically deformable baffle member (303) of the aircraft airflow changing device (301) in a corresponding first state extends through the opening (421), and wherein when the elastically deformable base member (305) is in a first state, the elastically deformable baffle member (303) of the aircraft airflow changing device (301) in a corresponding first state extends through the opening (421). When the elastically deformable base member (305) is in the second state, the elastically deformable baffle member (303) in the corresponding second state of the aircraft airflow changing device (301) is retracted from the opening (421); and wherein the fluid muscle actuator structure (801) is configured to apply a force to the elastically deformable base member (305) of the aircraft airflow changing device (301) so as to deform the elastically deformable base member (305) from the first state to the second state or to deform the elastically deformable base member (305) from the second state to the first state.

2. The vortex generator structure (115) according to claim 1, wherein: The first state of the elastically deformable baffle member (303) and the corresponding first state of the elastically deformable base member (305) are non-buckled states.

3. The vortex generator structure (115) according to claim 1 or 2, wherein: The fluid muscle actuator structure (801) is configured to provide a force substantially in the direction of a transverse axis of the elastically deformable base member (305).

4. The vortex generator structure (115) according to claim 1 or 2, wherein: The fluid muscle actuator structure (801) further comprises at least one connector (805), wherein the at least one connector (805) is configured to offset the fluid muscle actuator (803) of the fluid muscle actuator structure (801) by a distance D relative to the airflow changing device (301).

5. The vortex generator structure (115) according to claim 4, wherein: The distance D is 10 mm.

6. The vortex generator structure (115) according to claim 4, wherein: The fluid muscle actuator (803) is configured to be pivotably connected to the coupling (805).

7. The vortex generator structure (115) according to claim 4, wherein: The body of the coupler (805) is configured to extend from the airflow changing device (301) in a substantially vertical direction.

8. The vortex generator structure (115) according to any one of claims 1 to 2, 5 to 7, wherein: The fluid muscle actuator structure (801) is pneumatically driven.

9. The vortex generator structure (115) according to any one of claims 1 to 2, 5 to 7, wherein: The fluid muscle actuator structure (801) is hydraulically driven.

10. The vortex generator structure (115) according to any one of claims 1 to 2, 5 to 7, wherein: The fluid muscle actuator structure (801) is configured to operate within a pressure range of 0Pa to +600000Pa relative to ambient pressure.

11. The vortex generator structure (115) according to any one of claims 1 to 2, 5 to 7, wherein: The fluid muscle actuator structure (801) is configured to have an extended length of approximately 60 mm.

12. The vortex generator structure (115) according to claim 4, wherein: The elastic strain energy stored by the fluid muscle actuator (803) and the elastically deformable base member (305) is sufficient to cause the airflow altering device (301) to deploy.

13. The vortex generator structure (115) according to claim 4, wherein: The elastic strain energy stored by the fluid muscle actuator (803) is sufficient to cause the airflow changing device (301) to deploy.

14. An aircraft (101) having at least one vortex generator structure (115) according to any one of claims 1 to 13.

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