Rotorcraft, aircraft and method for operating an aircraft

Abstract

The rotor (22) of the rotor- wing device (1) in the wing (11) has an inlet opening (21) which can be closed by the closure (3) and a discharge opening (25) which can be closed by the closure (3). Here, the closure (3) is partially air-permeable in the closed state. This air permeability can influence the aerodynamic properties of the wing (11) in a targeted manner in the event of operation of the rotor (22) and closure (3) being closed. As a result, by means of the negative pressure in the region of the inlet opening (21) of the rotor (22) within the wing (11), suction of air on the top side of the wing can be achieved, and at the same time, by means of the overpressure in the region of the discharge opening (25), blowing out of air on the bottom side of the wing can be achieved. Advantageously, as a result, the decelerated boundary layer on the top side of the wing can reduce its thickness (δG) by means of the suction in the region of the inlet opening (21), and a higher-energy outer layer can be applied to the profile of the wing (11). More advantageously, the air resistance of the wing (11) can be reduced and its lift increased, which achieves better flight characteristics and higher energy efficiency of the aircraft having the rotor- wing device (1) according to the invention. Particularly advantageously, suction in the region of the closure (3) of the inlet opening (21) of the rotor (22) is achieved, which would otherwise form a thicker boundary layer (δ G ) in the region as a result of the unevenness on the surface caused by the closure (3).

Description

[0001] The invention relates to a wing-rotor device, to an aircraft and to a method for operating an aircraft.

[0002] Aircrafts which can take off and land vertically (VTOL - Vertical Take off and Landing) are known in a variety of different embodiments. The main advantage of such aircrafts is that the requirements for the site for take-off and landing are less and a landing runway is not required. At the same time, horizontally oriented drives can achieve a significantly higher travel speed than, for example, helicopters.

[0003] For example, a suitable aircraft with turbine drives can direct the propeller thrust downward by means of jet deflection in order to take off and land. In document DE 2924504 A1 a gas turbine engine is specified which directs the thrust in a vertical direction downward by means of a thrust deflection device and thereby enables the aircraft to take off and land vertically. The disadvantage of this solution is that it is only suitable for turbine propellers, wherein the noise and exhaust emissions make it almost impossible to use in urban areas.

[0004] Also in document DE 42 37 873 A1 a suitable aircraft for vertical take-off and landing is specified. For this purpose, the air flow of at least one propeller is directed by means of an air control system on the wings of the aircraft, so that the necessary lift for vertical take-off and landing is generated. The disadvantage is that this solution also uses the air flow of turbine jet propellers, so that the use in urban areas seems unlikely.

[0005] Furthermore, in document DE 1 935857 U an aircraft or spacecraft is specified, wherein the air flow is pressed into a chamber by means of a fan, from which the air can be blown out by means of channels which are alternately opened and closed in opposite directions. The channels are then also used to control the aircraft in high-speed flight. Turbine propellers or propellers with recoil devices are recommended as the fan. Disadvantageously, these cannot be used in residential areas either.

[0006] Furthermore, propeller-driven aircrafts with so-called tilt-rotors are also known, wherein the rotors can be rotated in order to achieve a transition from vertical flight to horizontal flight, i.e. a so-called transition phase, so that a vertical thrust for take-off and landing and a horizontal thrust for flight operation can be generated by means of the rotors. The disadvantage of tilt-rotors is the high technical requirements for the blade control of the rotors and the movable connection of the rotors.

[0007] A flying machine is specified in document DE 299 16203 U1 in which a rotor is integrated in a wing, which rotor can generate a vertical thrust. Thereby, the flying machine can take off or land vertically. When transitioning to a flight operation, a horizontal, i.e. wind direction oriented along the wing, rotor on the rear of the flying machine is activated. The opening in the wing for the rotor is closed by a blind curtain device for the flight operation, and the wing then provides sufficient lift and can be flown through in the manner of a conventional fixed-wing flying machine.

[0008] This technical solution is based on the fact that the aerodynamic properties of the wing are poor when the blind curtain device is closed. Due to the gaps and unevennesses on the wing surface caused by the blind curtain device, the transition from a laminar to a turbulent fluid mechanical boundary layer is promoted, and thereby the lift of the wing is reduced and the fluid resistance is increased. Even more disadvantageously, the rotor is not used when the blind curtain device is closed, and only serves to increase the weight of the flying machine.

[0009] The technical problem addressed by the present invention is currently to provide a wing-rotor device, a flying machine and a method for operating a flying machine, which overcome the above-mentioned disadvantages of the prior art.

[0010] The wing-rotor device according to the invention comprises a rotor arranged in a wing. The propulsion direction of the rotor is here essentially oriented perpendicular to the wind direction of the wing. The wing of the wing-rotor device is here used for a flight operation in which the flying machine obtains its lift by the inflow, or rather the onflow, of the wing. In the take-off and landing operation, the flying machine obtains the necessary lift by the air flow of the rotor arranged in the wing of the wing-rotor device according to the invention.

[0011] According to the invention, the rotor in the wing has an inlet opening which can be closed by a closure and an outlet opening which can be closed by a closure. Here, the closure is partially air-permeable in the closed state.

[0012] This permeability can influence the aerodynamic properties of the wing in a targeted manner in the case of a rotor running and the closure being closed. A suction of air on the top side of the wing can then be achieved by means of the negative pressure in the area of the intake of the rotor in the wing. Advantageously, the decelerated boundary layer on the top side of the wing can reduce its thickness in the area of the intake due to the suction and a higher- energy outer layer can be applied to the profile of the wing. At the same time air is blown out on the bottom side of the wing, thereby advantageously achieving a stabilization of the boundary layer, which can significantly increase the lift of the wing. More advantageously, the air resistance of the wing can be reduced and its lift increased, which achieves better flight characteristics and a higher energy efficiency of the aircraft with the rotor- wing arrangement according to the invention. It is particularly advantageous to achieve the suction in the area of the closure of the intake of the rotor, where a thicker boundary layer would otherwise be formed due to the unevenness on the surface caused by the closure.

[0013] It is particularly advantageous that, according to the invention, a rotor- wing arrangement is provided by means of a small number of extremely cost-effective changes, which not only overcomes the disadvantages in the prior art, i.e. the poor aerodynamic properties of the wing-rotor arrangement with the closure, but also simultaneously achieves a targeted control of the aerodynamic properties of the wing-rotor arrangement.

[0014] According to the invention, a suction of air on the surface of the wing, i.e. in the area of the intake of the rotor, and a blowing out of air on the bottom side in the area of the discharge of the rotor is achieved. The rotor thus still works in the direction of the vertical downward thrust in the flight operation with the closure of the intake and the discharge, and thereby forms a negative pressure on the top side of the wing in the area of the intake of the rotor and an overpressure on the bottom side of the wing in the area of the discharge of the rotor. The area between the intake and the rotor is therefore also referred to as an overpressure chamber and the area between the discharge and the rotor is also referred to as a negative pressure chamber.

[0015] In a preferred design of the wing-rotor arrangement, the closure or the area of the surface of the wing in which the closure is arranged has a plurality of openings distributed in a planar manner. Here, the openings establish a fluid- mechanical connection between the gap between the rotor and the closure of the intake on the surface of the wing. The openings are thus fluid- mechanically connected to the negative pressure generated by the operation of the rotor and suck air on the surface of the wing. Advantageously, the openings distributed in a planar manner simultaneously suck the boundary layer in a planar manner. Here, the specific number of openings, their size, spacing and direction are related to the design of the wing and the design of the aircraft and can be determined by a person skilled in the art in the scope of experiments or simulations. Preferably, the openings are cylindrical holes here, since the openings should be simple and cost-effective to open. The openings can also be conical holes or have an inclination angle.

[0016] Preferably, the closure has between 3 and 100, further preferably between 4 and 50 and particularly preferably between 5 and 20 openings per square meter. The openings preferably have a diameter of between 0.01 and 5 mm, further preferably between 0.03 and 1 mm and particularly preferably between 0.05 and 0.2 mm. Advantageously, the aircraft with a wing-rotor device of this type of design can be excellently controlled.

[0017] In an alternative design, the closure is at least partially porous. The porosity can be introduced, for example, by a sintering process when manufacturing the closure. Advantageously, a particularly good uniform distribution of the suction openings can be achieved by the porosity of the surface, and thus also a uniform suction and / or blowing area.

[0018] In another alternative design, the air permeability of the closure is achieved by its gaps and openings due to the structure. This can be, for example, the gaps of a blind (or as a louver). Here, the direction of the air suction and / or blowing can advantageously be used to purposefully control the aerodynamic properties of the wing-rotor device by the design of the edges that constitute the gaps, and the size of the air flow can be used to purposefully control the aerodynamic properties of the wing-rotor device by the size of the openings and gaps.

[0019] Here, the design of the edges that constitute the gaps can be varied to influence the direction of the air suction and / or air blowing, and / or the size of the openings and gaps inside the closure can be varied in order to further optimize the aerodynamic properties of the wing during flight operation.

[0020] Here, depending on the requirements of the specific aerodynamic design of the aircraft, different designs that ensure air permeability can be used within the wing-rotor device, such as cylindrical holes for suctioning air and sintered blind louvers for blowing air, or vice versa.

[0021] In a preferred design of the closure, the closure has at least one means for adjusting the blowing and / or suction direction of at least one opening. Preferably, multiple or all openings have a means for adjusting the blowing and suction of air. Advantageously, by adjusting the blowing and / or suction direction, the aerodynamic properties of the wing can be differentiated according to the specific requirements of the current flight state during flight operation. This advantageously enables good controllability during the transition phases of the aircraft.

[0022] In another preferred design of the wing-rotor device, at least one of the openings of the closure is configured to be closable. Particularly preferably, a plurality of the openings or all of the openings are configured to be closable. To this end, the openings have a closure device, for example in the form of a vane or an inflatable closure element in the fluid channel of the opening. Advantageously, further control measures of the aerodynamic properties of the rotor- wing device are thereby provided.

[0023] In a preferred design of the wing-rotor device, the rotor is a double rotor. The double rotor is here a rotor with two rotor blades arranged one above the other. The two rotor blades are usually operated in opposite rotational directions in order to compensate for the torque. Advantageously, the efficiency of the rotor is thereby improved, and the air quantity in the suction and blowing of air is thereby also increased.

[0024] In another preferred design of the wing-rotor device, at least one device for pressure regulation is arranged between the closure and the rotor. The device for pressure regulation can for example be an air channel with an adjustable air quantity. The air channel can here for example be guided from the region of the intake of the rotor to the region of the discharge and / or to a specific region of the wing, for example a wing region in the direction of the wind, forwards or backwards. By means of the device for pressure regulation, the air quantity to be sucked and / or to be blown can be controlled by influencing the pressure. Advantageously, the controllability of the wing-rotor device is further improved.

[0025] Particularly preferably, at least one device for pressure regulation is arranged between the rotor and the closure on both sides of the rotor. Advantageously, the air flow to be sucked or to be blown can thereby be controlled even more precisely.

[0026] In another preferred design of the wing-rotor device, the wing also has openings outside the closure element, which are fluid-dynamically connected to the region before or after the rotor, i.e. to the region of the intake or the discharge. Advantageously, the advantages of the present application, i.e. the targeted influencing of the boundary layer, can be used not only in the region of the closure element, but also on the entire surface of the wing. This can be achieved in a simple manner and method by means of fluid channels, which preferably have a valve.

[0027] The aircraft according to the application has at least one wing-rotor device according to the application. Preferably, the aircraft has two, three or four wing-rotor devices according to the application. Advantageously, the aircraft can be excellently controlled, even in the transition phase.

[0028] In a preferred design of the aircraft, the aircraft has one or more sensors for detecting parameters for determining the flight state. The control device can purposefully optimally adjust the aerodynamic properties of the at least one wing-rotor device for each flight state by comparing the sensor data with stored experimental data. To this end, the aircraft preferably has a control device and a storage device in which control data for, for example, the air quantity, the blow-out or blow-in direction and, if necessary, the blow-in position and / or blow-out position on the top side of the wing and / or the closure element corresponding to different flight states are stored.

[0029] A particular advantage of the application is that a rotor-wing device can be provided using simple changes which not only overcomes the disadvantages of the prior art, i.e. the adverse effect on the aerodynamic properties of the wing in the region of the closure element, but also compensates for, or even further improves, the aerodynamic properties.

[0030] The method for operating an aircraft relates to an aircraft comprising:

[0031] at least one wing having an integrated rotor, wherein the rotor has a thrust direction perpendicular to the wind direction of the wing.

[0032] a drive having a thrust direction in the wind direction of the wing,

[0033] a closure for closing the inlet opening of the rotor and a closure for closing the outlet opening, wherein the closure is at least partially air-permeable in the closed state.

[0034] The method for operating an aircraft according to the application is characterized in that air is purposefully drawn in and blown out in the region of the closure of the inlet opening and / or the outlet opening of the rotor of the wing-rotor device. Preferably, the drawing in and blowing out of air is achieved by the operation of the rotor of the rotor-wing device during the flight operation.

[0035] In a further preferred design of the method, the method comprises further method steps, for example:

[0036] vertical take-off and / or landing of the aircraft having an open closure with an inlet opening and / or an outlet opening,

[0037] opening the drive and starting the transition from the take-off and / or landing operation to the flight operation by movement in the wind direction of the at least one wing;

[0038] closing the closure.

[0039] For another preferred design of the method, the aircraft has a control device, a storage device and sensor devices for detecting the current flight state. Here, data on a large number of flight states and associated data on control data corresponding to the air quantity, the blow-out or blow-in direction and, if necessary, the blow-in position and / or the blow-out position on the top side of the wing and / or the closure are stored in the storage device.

[0040] Further preferred design features of the application result from the remaining features mentioned in the description.

[0041] If not stated otherwise, the different embodiments and design features of the rotor-wing device, the aircraft and for operating the aircraft can be advantageously combined with one another in the present application.

[0042] The application is explained in the following embodiments according to the drawings. In the drawings:

[0043] Figure 1 a top view of a wing-rotor device is shown,

[0044] Figure 2 a top view of a wing-rotor device with an open closure is shown,

[0045] Figure 3 a sectional view of a wing-rotor device is shown,

[0046] Figure 4 a sectional view of a wing-rotor device with an open closure is shown,

[0047] Figure 5 an enlarged view of a blade of a closure is shown,

[0048] Figure 6 a sectional view of a blade of a closure is shown, and

[0049] Figure 7 a sectional view of a blade of a closure with different embodiments of openings is shown.

[0050] Figure 1 a top view of a rotor-wing device 1 is shown, which has a wing 11 and an intake 21 of a rotor. Here, the intake 21 of the rotor is closed by means of a closure 3, which consists of a blind curtain with blades 31.

[0051] Figure 2 a view according to Figure 1 is shown with an open closure 3, that is to say the blades 31 of the closure 3 are turned up and the rotor can draw air through the closure (3).

[0052] Figure 3A sectional view of the rotor-wing device 1 is shown. The wing 11 has the usual cross-sectional shape of a wing, which in the case of an air flow with a wind direction 12 constitutes an upward force, i.e. a lift. Inside the wing 11 a rotor 22 is arranged. An inlet opening 21 and an outlet opening 25 are closed by a closure 3. Between the rotor 22 and the closure 3 of the outlet opening 25 a pressure chamber 24 is constituted by the rotation of the rotor, and between the rotor and the closure 3 of the inlet opening 21 a negative pressure chamber 23 is constituted.

[0053] The vane 31 of the closure 3 is in the closed position. The vane 31 is open with a hinge with a rotation axis 311. In addition, the vane 31 has an opening 312 in the form of a cylindrical hole with a connection between the negative pressure chamber 23 or the pressure chamber 24 and the surface of the closure 3. Thus, air is sucked in at the inlet opening 21 and blown out at the outlet opening. According to Figure 3 The view according to

[0054] Figure 4 A sectional view with the open closure 3 is shown according to Figure 3 For this purpose, the vane 31 is rotated about the rotation axis 311, so that the inlet opening 21 and the outlet opening 25 are open. The rotor 22 is in operation, and at this time the air flow, which is necessary for vertical take-off and landing, can be moved unhindered.

[0055] Figure 5 A detailed view of the vane 31 is shown. The vane 3 has a plurality of openings 312 distributed over its surface, through which air is sucked in and blown out. On the left side of the view an enlarged view of a plurality of openings 312 evenly distributed over the surface of the vane 31 is shown.

[0056] Figure 6A cross-sectional view of the blade 31 is shown. The cylindrical hole constitutes the opening 312. In the upper area of the view two diagrams are shown which show the fluid velocity V and the corresponding boundary layer thickness δG in relation to the distance from the surface of the wing. The boundary layer thickness δG is defined here as the distance from the wing within which at least 99% of the undisturbed fluid velocity Vo is reached. Here, the diagram on the left shows the boundary layer which is configured in the area of the closure 3 without openings 312 according to the application in the blade 31, while the diagram on the right shows the boundary layer on the wing 11 with openings 312 according to the application in the blade 31. It can be seen in the diagrams that the boundary layer thickness δG is significantly reduced by the air suction through the openings 312. This achieves a higher lift and a lower air resistance and thus brings about a significant energy saving and a more pronounced increase in flight safety through the improved controllability of the aircraft.

[0057] Figure 7 A blade 31 of the closure 3 is shown. Different forms of openings 312 are shown exemplarily. All shown openings 312 can be used for sucking and blowing out air. Thus, conical openings 312, 315 are shown. With this type of opening it is possible to accelerate or decelerate the air flow depending on the fluid direction. Inclined openings 313, 314 can determine the blowing or sucking direction, through the use of which it is also possible to adjust the aerodynamic properties of the wing 11.

[0058] List of reference signs

[0059] 1 wing-rotor device

[0060] 11 wing

[0061] 12 wind direction

[0062] 21 inlet

[0063] 25 outlet

[0064] 22 rotor

[0065] 23 underpressure chamber

[0066] 24 overpressure chamber

[0067] 3 closure

[0068] 31 blade

[0069] 311 rotation axis

[0070] 312, 315 conical opening

[0071] 313, 314 inclined opening

[0072] δ Gthickness of the boundary layer

[0073] A distance from the surface of the wing

[0074] V fluid velocity

[0075] V0 undisturbed fluid velocity

Claims

1. A wing-rotor arrangement (1) having a rotor (22), said rotor being arranged in a wing (11) such that the thrust direction of the rotor (22) is oriented perpendicularly to the wind direction of the wing (11), wherein: The rotor (22) has an inlet opening (21) in the wing (11) which can be closed by a closure element (3) and an outlet opening (25) which can be closed by a closure element (3), wherein the closure element (3) is partially air-permeable in the closed state.

2. The wing-rotor arrangement (1) according to claim 1, characterized in that The closing element (3) has openings distributed over a large area.

3. The wing-rotor arrangement (1) according to claim 1, characterized in that The closure element (3) is at least partially porous.

4. The wing-rotor arrangement (1) according to claim 1, characterized in that The gaps and openings of the closure (3) ensure air permeability.

5. The wing-rotor arrangement (1) according to claim 2, characterized in that The closure (3) comprises means for adjusting the orientation of at least one opening (312).

6. The wing-rotor arrangement (1) according to claim 2 or 5, characterized in that At least one opening (312) is closable.

7. The wing-rotor arrangement (1) according to claim 1, characterized in that The rotor (22) is a double rotor.

8. The wing-rotor arrangement (1) according to claim 1, characterized in that At least one device for pressure regulation is arranged between the closure element (3) and the rotor (22).

9. The wing-rotor arrangement (1) according to claim 7, characterized in that A device for pressure regulation is arranged on each side of the rotor (22) between the rotor (22) and the closure element (3).

10. The wing-rotor arrangement (1) according to claim 1, characterized in that The wing (11) has an opening on its top side and / or bottom side outside the closure (3), wherein the opening on the top side is connected to the space between the rotor (22) and the closure (3) of the inlet (21), and / or the opening on the bottom side is connected to the space between the rotor (22) and the closure (3) of the outlet (25).

11. An aircraft having at least one wing-rotor arrangement (1) according to any one of claims 1 to 10.

12. A method for operating an aircraft, the aircraft comprising at least one wing (11) with an integrated rotor (22), the rotor being arranged in the wing (11) and having a thrust direction perpendicular to a wind direction (12) of the wing (11), the aircraft comprising a drive having a thrust direction in the wind direction of the wing (11), wherein: The wing (11) has an inlet (21) of the rotor (22) that can be closed by a closure (3) and an outlet (25) that can be closed by the closure (3), wherein the closure (3) is at least partially air-permeable in the closed state, characterized in that air is purposefully sucked in and blown out in the region of the closure (3) of the inlet (21) and / or outlet (25) of the rotor (22) of the wing-rotor arrangement (1) in order to use the rotor (22) for vertical take-off and landing of the aircraft, and that the aerodynamic properties of the wing are influenced by the partial air permeability of the closure when the closure is closed.

13. Method for operating an aircraft according to claim 12, characterized in that At least one of the following steps is additionally performed: a) Vertical take-off aircraft with an open enclosure (3); b) activating the drive and transitioning to a flight operation in which at least one wing (11) moves in the direction of the wind (12); c) Close the closure (3).

14. Method for operating an aircraft according to claim 12 or 13, characterized in that The aircraft has a control device, a memory device, and a sensor device, wherein the sensor device detects the current flight state and compares the current flight state with data in the memory device via the control device and executes corresponding control data for the suction and discharge of air.

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