Technical Field of the Invention

The present invention relates to an aerodynamic device. In particular, the invention relates to an aerodynamic device such as a wing for an aircraft.

Background to the Invention

An aircraft typically undertakes three phases during a flight - ascent, cruise and descent. During descent of an aircraft a significant amount of energy (both kinetic and potential) must be dissipated in order to be able to land the aircraft safely and effectively. This is achieved through reducing altitude and speed, typically by increasing drag using a flap arrangement on the wings of the aircraft. In reducing speed, a reduction in lift is also experienced which is generally compensated for by the flap arrangement by increasing the camber and area of the wing to increase the lift coefficient. In conventional systems which operate in this manner, little to none of the dissipated kinetic and potential energy of the aircraft is recovered.

It is known to use fluid structure interaction to generate or recover energy. However, to date, no complete solution has been provided. It would be advantageous to provide an arrangement which could recover at least some of the otherwise dissipated energy during a descent phase of an aircraft.

It is therefore an aim of an embodiment or embodiments of the invention to improve upon the prior art.

Summary of the Invention

According to an aspect of the invention there is provided an aerodynamic device, the aerodynamic device comprising a body portion having a leading edge and a trailing edge; a conduit within the body portion, the conduit comprising an inlet at or proximal to the leading edge of the body portion and defining a flowpath through the body portion; one or more airflow disrupters positioned within the conduit and configured, in use, to disrupt the airflow through the conduit; and one or more energy recovery devices positioned within the conduit operable to recover energy from the disrupted airflow through the conduit. Advantageously, the aerodynamic device may be used to recover energy, for example, during a descent phase of an associated aircraft through fluid structure interaction between the aerodynamic device and the airflow across (and in this case through) the device.

The width of the conduit may, in embodiments, be substantially equal along its length. In other embodiments the width of the conduit may vary along its length. For example, in some embodiments the width of the conduit may decrease along its length, e.g. between the inlet and the distal end of the conduit which may, in embodiments, comprise an outlet. Variation of the width of the conduit along its length may be used to control the velocity of the airflow through the conduit, and in embodiments, the velocity of air flowing out of the conduit through an outlet.

The conduit may extend substantially the entire distance between the leading and trailing edges of the body portion of the aerodynamic device. In other embodiments, the conduit may extend no more than 90%, or no more than 80%, or no more than 70%, or no more than 60% of the distance between the leading and trailing edges of the body portion. In embodiments, the conduit may extend between 60% - 90%, or between 60% - 75%, or between 60% - 70% of the distance between the leading and trailing edges of the body portion, for example. In presently preferred embodiments, the conduit may extend approximately two thirds of the distance between the leading and trailing edges of the body portion. Where the device comprises a wing for an aircraft, the distance between the leading and trailing edges of the body portion may be referred to as a chord.

In embodiments the conduit may be substantially straight. That is, the path between the inlet of the conduit and a distal end, which may be an outlet, of the conduit may be substantially straight. In alternative embodiments the conduit may be curved. That is, the path between the inlet and a distal end, which may be an outlet, of the conduit may follow a curved path. The curved path may be particularly beneficial in embodiments wherein the conduit comprises an outlet which may be used to direct airflow from the conduit with respect to one or more components of the aerodynamic device, e.g. an external surface of the device. Providing a curved conduit may enable the direction of airflow through an outlet in the conduit to be controlled. The conduit comprises an inlet at or proximal to the leading edge of the body portion. In embodiments the body portion comprises a front surface which is preferably curved. The foremost portion of the front surface may herein be referred to as the leading edge of the body portion. In embodiments the inlet is provided below the leading edge of the body portion, for example, the inlet is provided within the front surface of the body portion but below the foremost portion thereof.

In embodiments, the inlet may span a substantial portion of the width of the body portion of the aerodynamic device. In some embodiments the inlet may span at least 25%, or at least 50%, or at least 75% of the width of the body portion. In embodiments, the inlet may span between 25% - 75%, or between 30% - 70%, or between 40% - 60%, or between 50-90%, or between 60-80%, of the width of the body portion. In embodiments wherein the aerodynamic device comprises a wing for an aircraft, the device may include a flap arrangement, preferably at or proximal to a rear surface thereof. The rearmost portion of the rear surface may herein be referred to as the trailing edge of the body portion. In such embodiments, the inlet may span substantially the same proportion of the aerodynamic device as the flap arrangement.

In presently preferred embodiments the conduit comprises a single inlet. However, in some embodiments the conduit may comprise a plurality of inlets. In such embodiments, each of the plurality of inlets may be configured as described herein.

The conduit may comprise an outlet. The outlet may be provided at a distal end of the conduit from the inlet. The outlet may be provided at or proximal to the trailing edge of the body portion of the aerodynamic device. In some embodiments the outlet may be provided within an upper surface of the body portion of the aerodynamic device.

The outlet may be configured (i.e. shaped, positioned, etc.) so as to control airflow leaving the conduit with respect to one or more components of the aerodynamic device. In some embodiments the outlet may be configured so as to direct airflow leaving the conduit onto one or more components of the aerodynamic device. For example, in embodiments wherein the aerodynamic device comprises a wing of an aircraft, the outlet may be configured to direct airflow across, onto or otherwise with respect to one or more flaps of a flap arrangement of the wing. The outlet may be substantially flat. That is, the outlet may be comprise a substantially rectangular cross-section having a width which is greater than its height (or conversely a height which is greater than its width). In this way, the outlet may be configured such that airflow out from the conduit through the outlet is substantially tangential to a surface of the aerodynamic device, e.g. to create a substantially laminar airflow across an upper surface of the body portion of the aerodynamic device, or to increase the total energy of the boundary layer of the upper surface. Advantageously, configuring the outlet in this manner may improve the lift coefficient of the aerodynamic device, thereby improving overall aerodynamic performance. This may be particularly useful where the aerodynamic device comprises a wing for an aircraft.

The outlet of the conduit may comprise an area substantially equal to the area of the inlet of the conduit. In presently preferred embodiments, for example embodiments wherein the width of the conduit varies with length, the area of the outlet may be different to the area of the inlet. In some embodiments the area of the outlet is smaller than the area of the inlet. For example, in some embodiments the area of the outlet may be smaller than the area of the inlet by a factor of at least 2, or at least 4, or at least 6, or at least 8, or at least 10, or at least 12. In presently preferred embodiments the outlet comprises an area which is smaller than the area of the inlet by a factor of between 10 and 12. In this way, the airflow out of the conduit through the outlet may be at an increased velocity when compared with the airflow through the inlet. This may be beneficial, for example, in embodiments wherein airflow from the outlet may be directed onto, across or otherwise with respect to one or more further components of the aerodynamic device.

In presently preferred embodiments the conduit comprises a single outlet. However, in some embodiments the conduit may comprise a plurality of outlets. In such embodiments, each of the plurality of outlets may be configured as described herein.

In embodiments, the aerodynamic device may comprise a shutter arrangement configured, in use, to control airflow through the conduit. The shutter arrangement may be provided at or proximal to the inlet of the conduit. In embodiments a shutter arrangement may be provided at or proximal to the outlet of the conduit. In embodiments there may be provided a shutter arrangement at or proximal to the inlet of the conduit and a shutter arrangement provided at or proximal to the outlet of the conduit.

The shutter arrangement may comprise a closure member configured to at least partly cover the inlet of the conduit thereby preventing airflow through the inlet and into the conduit of the aerodynamic device. The shutter arrangement may be moveable between a configuration wherein the inlet is substantially uncovered and a configuration wherein the inlet is at least partly covered. Such an arrangement may be particularly beneficial during, for example, phases of flight of an aircraft where energy recovery is not beneficial - i.e. where energy recovery would be counter-productive - for example, during ascent and cruise phases of flight.

The one or more airflow disrupters may, in some embodiments, comprise a single airflow disrupter positioned within the conduit. In other embodiments, the aerodynamic device comprises a plurality of airflow disrupters located at different positions along the length of the conduit.

The one or more airflow disrupters may comprise an additional component positioned within the airflow through the conduit. The airflow disrupter(s) may be integrally formed within the conduit or in other embodiments be suitably mounted within the conduit. In such embodiments the one or more airflow disrupters form an obstruction within the conduit and cause airflow through the conduit to be directed about the obstruction in a plurality of directions to induce turbulences in the airflow.

The one or more airflow disrupters may comprise a polygonal (e.g. triangular) cross section. In such embodiments, the airflow disrupter(s) may be positioned within the conduit such that airflow through the conduit is incident on an edge thereof, e.g. a leading edge, configured to direct airflow through the conduit in at least two directions about the disrupter(s) to induce turbulences in the airflow.

In some embodiments the one or more airflow disrupters may comprise a circular or semi-circular cross-section, or may be otherwise configured with a curved surface on which airflow through the conduit may be incident, in use. In such embodiments the one or more airflow disrupters may be configured such that airflow incident on the dismpter(s) is directed in a plurality of directions about the disrupter(s) to induce turbulences in the airflow.

In some embodiments the one or more airflow disrupters may comprise a variation in an internal surface/wall of the conduit. That is, the conduit may comprise one or more airflow disrupters in the form of ridges and/or detents in an internal surface/wall of the conduit to cause airflow through the conduit to be directed about the ridges/detents in a plurality of directions to induce turbulences in the airflow.

The one or more energy recovery devices may comprise a turbine. The turbine may comprise a rotor assembly provided within airflow through the conduit configured to rotate upon interaction with the airflow. The rotation of the rotor assembly may be used to operate a generator for generating electrical energy.

In some embodiments, the one or more energy recovery devices may comprise a transducer, for example, an electrical transducer. The transducer may comprise a piezoelectric device configured to generate an electrical output in dependence on an applied pressure - e.g. through interaction with the airflow through the conduit. In such embodiments, the transducer may be provided within the airflow through the conduit and, in use, the transducer may be operable to vibrate upon interaction with the airflow.

In some embodiments the transducer may be mounted on or otherwise coupled to a supporting member within the conduit. In such embodiments, the supporting member may be configured to vibrate upon interaction with the airflow through the conduit. The size, shape, configuration and/or positioning of the supporting member within the conduit may be such that the supporting member is configured to vibrate upon interaction with the airflow through the conduit at a frequency approximately equal to a preferred operational frequency (e.g. a resonant frequency) of an associated transducer. The preferred operational frequency of the transducer may correspond to a frequency of peak efficiency for the transducer, or may correspond to a frequency at or just below the undamped natural frequency of the transducer.

In embodiments, the aerodynamic device comprises a plurality of a transducers. Each of the plurality of transducers may be mounted on or otherwise coupled to one of one or more supporting members provided within the conduit. For example, there may be provided a plurality of supporting members with one or more transducers provided on each supporting member.

In embodiments wherein the one or more energy recovery devices are mounted or otherwise coupled to a supporting member, the (or each) supporting member may comprise part of an airflow disrupter within the conduit. For example, one or more energy recovery devices may be mounted or otherwise coupled to a surface of an airflow disrupter.

The supporting member may be formed of a rigid, semi-rigid or flexible material.

In some embodiments the aerodynamic device comprises a plurality of energy recovery devices. Each of the plurality of energy recovery devices may be of the same type. In alternative embodiments, the plurality of energy recovery devices may include two or more types of energy recovery devices - e.g. at least one turbine and at least one transducer.

In embodiments, the aerodynamic device comprises a plurality of conduits. In such embodiments, each of the plurality of conduits may comprise a conduit as described herein. For example, each of the plurality of conduits may comprise an inlet at or proximal to the leading edge of the body portion and defining a flowpath through the body portion; one or more airflow disrupters configured to disrupt the airflow through the conduit; and one or more energy recovery devices positioned therein.

The aerodynamic device may comprise an aerodynamic device for a vehicle such as an aircraft. In embodiments, the aerodynamic device comprises a wing for an aircraft.

According to a further aspect of the invention there is provided an aircraft comprising the aerodynamic device of a preceding aspect of the invention.

In embodiments the aerodynamic device comprises a wing of the aircraft.

Detailed Description of the Invention

In order that the invention may be more clearly understood one or more embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings, of which: Figure 1 is a cross-sectional view of an embodiment of an aerodynamic device in accordance with the invention;

Figure 2 is a cross-section view of a section of the aerodynamic device of Figure 1; Figure 3 is a plan view of the aerodynamic device of Figures 1 and 2; Figure 4 is a cross-sectional view of the aerodynamic device of the preceding Figures;

Figures 5A-5B are cross-sectional views of embodiments of an aerodynamic device in accordance with the invention; and Figures 6A-6C are cross-sectional views of further embodiments of an aerodynamic device in accordance with the invention.

An embodiment of an aerodynamic device 10 in accordance with the invention is shown in Figures 1-4.

In general, the aerodynamic device comprises a wing 10 for an aircraft 32. The wing 10 comprises a body portion 12 which includes a conduit 18 defining a flowpath through the body portion 12 for air incident on the wing 10. One or more airflow disrupters 24 are provided within the conduit 18 and are each configured, in use, to disrupt the airflow through the conduit 18 causing it to become more turbulent. Further, one or more energy recovery devices 26 are provided within the conduit 18 and are operable, in use, to recover energy from the airflow through the conduit 18.

The body portion 12 includes an upper surface 19, lower surface 21, a leading edge 14 and a trailing edge 16. The leading edge 14 defines part of a front surface 15 of the body portion 12, specifically the foremost portion of the front surface 15. The front surface 15 of the body portion 12 comprises a curved configuration for directing airflow incident on the wing 10 about the body portion 12. In the illustrated embodiment, the wing 10 includes a flap arrangement 30, with the rearmost edge of the flap arrangement 30 defining the trailing edge 16 of the body portion 12.

The conduit 18 defines a flowpath through the body portion 12 of the wing 10 and includes an inlet 20 proximal to the leading edge 14. Specifically, and as shown, the inlet 20 is provided within the front surface 15 but below the leading edge 14. The conduit 18 additionally includes an outlet 22 at a distal end of the conduit 18 to the inlet 20. The outlet 22 is provided within the upper surface 19 of the body portion 12, at approximately two thirds of the distance along the upper surface 19 of the body portion 12 from the leading edge 14 to the trailing edge 16. Further, the conduit 18 is curved between the inlet 20 and the outlet 22. This configuration allows air incident on the front surface 15 of the wing 10 to enter the conduit 18 through the inlet 20 before being expelled through the outlet 22 and over the remainder of the upper surface 19 of the wing 10 and on to the flap arrangement 30. This is illustrated specifically in Figure 4. As described herein, such an arrangement may provide improvements in aerodynamic efficiency of the wing 10 when compared with conventional arrangements.

In the illustrated embodiment the size of the conduit 18 varies along its length between the inlet 20 and the outlet 22. Specifically, the width of the conduit 18 decreases along its length. This configuration allows for control over the velocity of the airflow through the conduit 18 and out through outlet 22. Specifically, by reducing the width of the conduit 18 the velocity of the airflow out of the conduit 18 may be increased when compared with the air incident on the wing 10. This is particularly beneficial as the airflow from the outlet 22 may be directed over external surfaces of the wing 10 (such as the remainder of the upper surface 19 of the body portion 12 and/or the flap arrangement 30) for aerodynamic purposes (as is described herein).

Figure 3 illustrates how the width of the conduit 18 varies with length in the illustrated embodiment. Specifically, inlet 20 defines a relatively wide opening 23 for the intake of air incident on the front surface 15 of the wing 10. The conduit 18 narrows significantly to form a narrow portion 25. In this embodiment, the air flow disrupter(s) 24 and the energy recovery device(s) 26 are provided within the narrow portion 25 of the conduit 18.

As described herein, the outlet 22 is configured to control airflow leaving the conduit 18. Specifically, the outlet 22 is substantially flat and includes a substantially rectangular cross-section having a width which is greater than its height. In this way, the airflow out from the conduit 18 through the outlet 22 may be made substantially tangential to the upper surface 19 of the wing 10 to create a substantially laminar airflow across the upper surface 19 and on to the flap arrangement 30. In conjunction with the narrowing of the conduit 18, the shape of the outlet 22 may provide improvements in aerodynamic performance of the wing 10 as described herein.

In the illustrated embodiment, the wing 10 includes a shutter arrangement in the form of a closure member 28 positioned across the inlet 20 of the conduit 18. In use, the closure member 28 is configured to at least partly cover the inlet 20 of the conduit 18 to prevent air incident on the front surface 15 of the wing 10 from entering the conduit 18. This may be beneficial during, for example, phases of flight of an aircraft where energy recovery is not beneficial - i.e. where energy recovery would be counter productive - for example, during ascent and cruise phases of flight. The closure member 28 is moveable between the configuration shown in Figure 1 and a further configuration whereby the inlet 20 is substantially uncovered thereby allowing air incident on the front surface 15 of the wing 10 to enter the conduit 18. In some instances a closure member may also be provided across the outlet 22 of the conduit 18 for the same/similar purpose.

One or more airflow disrupters 24 are provided within the conduit 18 and are each configured, in use, to disrupt the airflow through the conduit 18 causing it to become more turbulent. Specifically, and as described herein, the airflow disrupters 24 are configured to direct the airflow through the conduit 18 about the disrupters 24 to induce turbulences in the airflow.

In the embodiment illustrated in Figures 1-4, the airflow disrupter(s) 24 comprise an additional component provided within the conduit 18 causing airflow F through the conduit 18 to be directed about the disrupter 24 causing the airflow to become more turbulent. Specifically, the disrupter 24 is provided substantially central within the conduit 18 and includes a triangular cross-section defining a leading edge 27 and a pair of surfaces 29 onto which the airflow F through the conduit 18 is incident. This configuration has the effect of directing airflow in a plurality of directions about the disrupter 24 and through a gap(s) 31 between the disrupter 24 and the wall of the conduit 18. Altering the direction of the airflow through the conduit 18 and directing the airflow through this gap(s) 31 causing the airflow to become more turbulent, for example by inducing shearing elements or shedding eddies into the airflow through the conduit 18. It will be appreciated that the configuration of the airflow disrupter 24 is not limited to the disrupter 24 shown in Figures 1-4. As is described hereinbelow, and with reference to Figures 5 A-6C, variations in the configuration of the airflow disrupter 24 are possible and are within the scope of this invention.

One or more energy recovery devices 26 are provided within the conduit 18 and are operable, in use, to recover energy from the airflow through the conduit 18. Specifically, the energy recovery device(s) 26 is/are provided within the conduit 18 downstream of the air flow disrupter(s) 24 such that the recovery device(s) may interact with the turbulent airflow within the conduit 18 and extract energy therefrom.

In the illustrated embodiment, the energy recovery devices include an electrical transducer 26 configured to generate an electrical output in dependence on interaction of the transducer 26 with the airflow through the conduit 18. Specifically, the transducer 26 is operable to vibrate upon interaction with the turbulent airflow through the conduit 18 caused by the airflow disrupted s) 24.

The transducer 26 is mounted on or otherwise coupled to a supporting member 40 within the conduit 18. The supporting member 40 is configured to vibrate upon interaction with the turbulent airflow within the conduit 18. The size, shape, configuration and/or positioning of the supporting member 40 within the conduit 18 is chosen such that the supporting member 40 vibrates upon interaction with the airflow through the conduit 18 at a frequency approximately equal to a preferred operational frequency (e.g. a resonant frequency) of the transducer 26.

In the illustrated embodiment the transducer 26 is provided on a supporting member 40 which is separate from the airflow disrupter 24. However, it will be appreciated that the invention is not limited in this sense. For example, in some embodiments the supporting member 40 may comprise part of the airflow disrupter 24. For example, the transducer 26 may be mounted on or otherwise coupled to a surface of the airflow disrupter 24.

Figures 5A - 6C are a series of cross-sectional views of embodiments of an aerodynamic device in accordance with the invention. Specifically, these Figures illustrate the airflow F through various configurations of the invention. Figure 5 A further illustrates the wing 10 of the preceding Figures. As shown, the wing 10 includes conduit 18 including a plurality of air flow disrupters 24. The disrupters 24 are as described herein comprising a triangular cross section. As shown, this particular arrangement has been shown to result in a relatively high level of turbulence induced in the airflow F through the conduit 18.

Figure 5B illustrates a variant 10' of the wing 10 shown in the preceding Figures. Specifically, wing 10 ^' includes a conduit 18 ^' including a plurality of airflow disrupters 24' along its length. The airflow disrupters 24' similarly define a triangular cross section but instead comprise a series of ridges extending from a side wall of the conduit 18 ^' which define a series of funnel-type arrangements which direct the airflow through a series of openings 3 G which are provided substantially central within the conduit 18 ^' .

Figure 6A illustrates a further embodiment of an aerodynamic device in the form of a wing 110 comprising a conduit 118 therethrough. The conduit 118 includes a plurality of airflow disrupters 124 along its length for disrupting the airflow F through the conduit 118 to induce turbulences therein. The airflow disrupters 124 are configured similarly to airflow disrupters 24 of wing 10, but instead are substantially circular in cross section defining a curved surface on which airflow F through the conduit 118 may be incident, in use. The curved surface acts to direct the airflow F about the disrupter 124 to induce turbulences therein. Figure 6B illustrates a similar embodiment to that shown in Figure 6 A. However, the wing 210 shown in Figure 6B includes airflow disrupters 224 having a hemi-spherical cross-section.

Figure 6C illustrates a further embodiment of an aerodynamic device in the form of a wing 310 comprising a conduit 318 therethrough. The conduit 318 includes a plurality of airflow disrupters 342 along its length for disrupting the airflow F through the conduit 318 to induce turbulences therein. The airflow disrupters 324 comprise a series of ridges and detents in the internal wall of the conduit 324 over which the airflow F through the conduit 318 may be incident, in use. The ridges and detents act to interfere with the airflow F through the conduit 318 to induce turbulences therein.

The one or more embodiments are described above by way of example only. Many variations are possible without departing from the scope of protection afforded by the appended claims.