Tilt-rotor aircraft resistance reduction structure and method

Abstract

The invention discloses a resistance reduction structure and method for a tilt-rotor aircraft. The resistance reduction structure comprises a fixed section wing, a tilt section wing, an aileron, a trailing edge blowing mechanism, a fairing, a motor nacelle, a propeller, a steering engine, a driving gear, a driven gear and a tilt shaft, and the trailing edge blowing mechanism comprises a high-pressure air chamber, a rotating shaft and a shifting piece; when the aircraft is in a helicopter mode, the trailing edge blowing mechanism blows air from the trailing edges of the tilting wings to the leading edges to separate airfoil airflows on the tilting wings, so that the resistance generated by high-speed airflows of propellers on the tilting section wings is reduced, and the tilting wing aircraft is more stable in hovering and taking-off and landing; the advantages of a helicopter aircraft and a fixed-wing aircraft are effectively combined, vertical take-off and landing and high-efficiency cruising speed can be achieved, and the problem that extra resistance is generated by a tilt-rotor aircraft in a helicopter mode is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of aircraft, and in particular to a drag reduction structure and method for a tilt-rotor aircraft. Background Art

[0002] In recent years, aviation technology has developed rapidly, especially with the introduction of low-altitude economy, various types of aircraft have grown rapidly, the most representative of which are aircraft that can achieve both fixed-wing and vertical take-off and landing flight modes. This type of aircraft does not require a runway for take-off, and does not require high conditions for take-off and landing, which makes this type of aircraft more applicable and versatile. At the same time, this type of aircraft takes into account the advantages of high cruise efficiency and long range of fixed-wing aircraft. Tilt-rotor aircraft is a variant aircraft that combines the characteristics of fixed-wing aircraft and helicopters. This type of aircraft can freely switch between helicopter mode and fixed-wing mode by controlling the tilt of the wings.

[0003] Tilt-rotor aircraft overcomes the drag loss caused by the impact of rotor downwash on the wing, which is only 1.2% of the rotor drag. However, in helicopter mode, the tilting of the main wing allows the lift of the aircraft to be completely provided by the rotor during forward flight. In addition, the high-speed slipstream generated by the rotation of the propeller will generate a lot of resistance when flowing through the tilt-rotor wing, affecting the stability of the tilt-rotor aircraft's vertical take-off and landing, and reducing flight efficiency. Summary of the invention

[0004] The purpose of the present invention is to solve the technical problems existing in the prior art and to provide a drag reduction structure and method for a tilt-rotor aircraft.

[0005] To achieve the above-mentioned purpose, the technical solution provided by the present invention is: a drag reduction structure of a tilt-wing aircraft, the drag reduction structure comprising a fixed-section wing, a tilt-section wing, and a trailing edge blowing mechanism; the fixed-section wing and the tilt-section wing are connected by a tilting mechanism, a trailing edge blowing mechanism is provided at the trailing edge of the tilt-section wing, a power assembly is provided at the front end of the tilt-section wing, the trailing edge blowing mechanism comprises a high-pressure air chamber, a rotating shaft, and a paddle, high-pressure gas is stored in the high-pressure air chamber, the paddle is connected to the tilt-section wing by a rotating shaft, the paddle rotates around the rotating shaft to change the direction of the high-speed airflow blown out by the high-pressure air chamber, and a gap is left between the paddle and the tilt-section wing.

[0006] Preferably, the tilt mechanism is composed of a driving gear, a servo, a driven gear, and a tilt shaft. The servo and driving gear are installed in combination in the tilt section wing. The driven gear is connected to the fixed section wing through the tilt shaft. The driven gear is meshed with the driving gear. The tilt mechanism rotates to drive the tilt section wing to tilt relative to the fixed section wing, thereby realizing the conversion of the aircraft between fixed wing mode and helicopter mode.

[0007] Preferably, the power assembly consists of a nacelle, a fairing and a propeller, the nacelle is arranged below the leading edge of the tilting section wing, and an electric motor is arranged in the nacelle.

[0008] Preferably, a propeller is installed at the front end of the nacelle through a hinge device; the fairing is transitionally connected to the lower side of the leading edge of the tilt section wing, and the fairing and the propeller are both connected to the motor in the nacelle.

[0009] Preferably, the tilting section wing is provided with an aileron, and the aileron is movably hinged in a connecting groove provided on the tilting section wing.

[0010] The present invention also discloses a method for reducing drag of a tilt-rotor aircraft, which is applied to the above-mentioned drag reduction structure of the tilt-rotor aircraft. The drag reduction method is as follows: when the aircraft is in helicopter mode, the paddle of the trailing edge blowing mechanism will rotate upward 90 degrees around the rotation axis to blow the high-speed airflow blown out of the high-pressure air chamber along the upper wing surface of the tilt-section wing toward the leading edge of the tilt-section wing, so that the airflow on the upper wing surface of the tilt-section wing is separated, thereby reducing the pressure difference between the upper and lower wing surfaces of the tilt-section wing, so as to reduce the drag generated by the high-speed slipstream of the propeller on the tilt-section wing.

[0011] Beneficial effects of the present invention:

[0012] The present invention adopts a design in which a tilting section wing and a fixed section wing are connected by a tilting mechanism, which effectively combines the advantages of a helicopter aircraft and a fixed-wing aircraft, and can achieve both vertical take-off and landing and a more efficient cruising speed.

[0013] The present invention, during the vertical take-off and landing stage of the tilt-wing aircraft, blows air toward the leading edge of the tilt-section wing through the trailing edge blowing mechanism, so as to change the airflow on the upper wing surface of the tilt-section wing, reduce the resistance generated by the tilt-section wing of the aircraft in the helicopter mode, and further make the aircraft more stable during the hovering and take-off and landing stage, and finally solve the problem of slippage of the tilt-wing aircraft during take-off and landing. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The drawings described herein are used to provide further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0015] Figure 1 An axial view of an aircraft wing in helicopter mode according to an embodiment of the present invention;

[0016] Figure 2 A top view of the aircraft wing in helicopter mode according to an embodiment of the present invention;

[0017] Figure 3 A front view of the aircraft wing in the helicopter mode according to an embodiment of the present invention;

[0018] Figure 4 An axial view of an aircraft wing tilt mechanism in an embodiment of the present invention;

[0019] Figure 5 A cross-sectional view of an aircraft trailing edge blowing mechanism in an embodiment of the present invention;

[0020] Figure 6 It is a top view of the aircraft trailing edge blowing mechanism in an embodiment of the present invention.

[0021] Figure annotation:

[0022] 1-fixed section of wing; 2-tilting section of wing; 3-trailing edge blowing mechanism; 31-high pressure air chamber; 32-rotating shaft; 33-paddle 4-aileron; 5-motor nacelle; 6-blade; 7-fairing; 8-driving gear; 9-servo; 10-driven gear; 11-tilting shaft. DETAILED DESCRIPTION

[0023] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it cannot be understood as a limitation on the scope of protection of the present invention.

[0024] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0025] In the description of the present invention, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood as not including the number itself, and "above", "below", "within" etc. are understood as including the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0026] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0027] Reference Figure 1-Figure 6, a preferred embodiment of the present invention, a drag reduction structure of a tilt-wing aircraft, the drag reduction structure comprising a fixed section wing 1, a tilt section wing 2, and a trailing edge blowing mechanism 3; the fixed section wing 1 and the tilt section wing 2 are connected by a tilting mechanism, and the rotation of the tilting mechanism drives the tilt section wing 2 to tilt relative to the fixed section wing 1, so as to realize the conversion of the aircraft between the fixed wing mode and the helicopter mode; a trailing edge blowing mechanism 3 is provided at the trailing edge of the tilt section wing 2, and a power assembly is provided at the front end of the tilt section wing 2, the trailing edge blowing mechanism comprises a high-pressure air chamber 31, a rotating shaft 32, and a paddle 33, the high-pressure air chamber 31 stores high-pressure gas, the paddle 33 is connected to the tilt section wing 2 by the rotating shaft 32, the paddle 33 rotates around the rotating shaft 32 to change the direction of the high-speed airflow blown out by the high-pressure air chamber 31, and a gap is left between the paddle 33 and the tilt section wing 2 to prevent the paddle 33 from getting stuck when rotating around the rotating shaft 32.

[0028] When the aircraft is in helicopter mode, the paddle 33 of the trailing edge blowing mechanism 3 will rotate upward 90 degrees around the rotating shaft 32 to blow the high-speed airflow blown out of the high-pressure air chamber 31 along the wing surface of the tilt section wing 2 toward the leading edge of the tilt section wing 2, so that the airflow on the wing surface of the tilt section wing 2 is separated, thereby reducing the pressure difference between the upper and lower wing surfaces of the tilt section wing 2, thereby achieving the purpose of reducing resistance.

[0029] Furthermore, the tilt mechanism is composed of a driving gear 8, a steering gear 9, a driven gear 10, and a tilt shaft 11. The steering gear 9 and the driving gear 8 are installed in combination in the tilt section wing 2. The driven gear 10 is connected to the fixed section wing 1 through the tilt shaft 11. The driven gear 10 is meshed with the driving gear 8. Figure 4 Preferably, the driving gear 8 and the driven gear 10 have the same specifications, and the steering gear 9 rotates to drive the tilting section wing 2 to rotate, thereby realizing the switching between the helicopter mode and the fixed-wing mode of the aircraft.

[0030] In this embodiment, the power assembly is composed of a nacelle 5, a propeller 6 and a fairing 7. The nacelle 5 is arranged below the leading edge of the tilting section wing 2, and a motor is arranged in the nacelle 5. The motor is arranged in the nacelle 5 to provide power for the aircraft. The propeller 6 and the fairing 7 are fixedly connected to the output shaft of the motor. The fixed connection of the two makes the operation of the power assembly more stable.

[0031] Furthermore, a propeller 6 is installed at the front end of the nacelle 5 through a hinge device; the fairing 7 is transitionally connected to the lower side of the leading edge of the tilting section wing 2, and the fairing 7 and the propeller 6 are both connected to the motor in the nacelle 5.

[0032] The tilting section wing 2 is provided with an aileron 4, which is movably hinged in a connecting groove provided on the tilting section wing 2. The aileron 4 is deflected by the rotation of the movable hinge mechanism to provide a rolling moment for the aircraft.

[0033] The present invention also discloses a method for reducing drag of a tilt-rotor aircraft, which is applied to the above-mentioned drag reduction structure of the tilt-rotor aircraft. The drag reduction method is as follows: when the aircraft is in helicopter mode, the paddle 33 of the trailing edge blowing mechanism will rotate upward 90 degrees around the rotation axis 32 to blow the high-speed airflow blown out of the high-pressure air chamber 31 along the upper wing surface of the tilt-section wing 2 toward the leading edge of the tilt-section wing 2, so that the airflow on the upper wing surface of the tilt-section wing 2 is separated, thereby reducing the pressure difference between the upper and lower wing surfaces of the tilt-section wing 2, so as to reduce the drag generated by the high-speed slipstream of the propeller 6 on the tilt-section wing 2.

[0034] The tilting section wing 2 of the present invention is connected to the fixed section wing 1 through a tilting mechanism, and can realize a 90-degree tilting perpendicular to the fixed section wing 1. At the same time, a power assembly is provided at the leading edge of the tilting section wing 2 to provide power for the aircraft. A trailing edge blowing mechanism 3 is provided at the trailing edge of the tilting section wing 2. When the aircraft is in helicopter mode, the high-speed airflow blown out of the high-pressure air chamber 31 in the trailing edge blowing mechanism 3 will blow air from the leading edge of the tilting section wing 2 to separate the airflow on the upper wing surface of the tilting section wing 2, so as to reduce the resistance generated by the high-speed airflow of the propeller 6 on the tilting section wing 2, thereby making the tilt-wing aircraft more stable in hovering and taking off.

[0035] The present invention adopts a trailing edge blowing mechanism and a design in which the tilting section wing 2 is connected to the fixed section wing 1 through a tilting mechanism, which effectively combines the advantages of a helicopter aircraft and a fixed-wing aircraft, can achieve vertical take-off and landing and a more efficient cruising speed, and solves the problem of additional resistance generated by the tilt-wing aircraft in helicopter mode.

[0036] Under the premise that no conflict occurs, those skilled in the art may freely combine and superimpose the above-mentioned additional technical features.

[0037] The above description is only a preferred implementation mode of the present invention. Any technical solution that achieves the purpose of the present invention by substantially the same means belongs to the protection scope of the present invention.

Claims

1. A drag reduction structure for a tilt-rotor aircraft, characterized in that: The drag reduction structure comprises a fixed section wing (1), a tilting section wing (2), and a trailing edge blowing mechanism (3); the fixed section wing (1) and the tilting section wing (2) are connected via the tilting mechanism; a trailing edge blowing mechanism (3) is provided at the trailing edge of the tilting section wing (2); a power assembly is provided at the front end of the tilting section wing; the trailing edge blowing mechanism comprises a high-pressure air chamber (31), a rotating shaft (32), and a paddle (33); high-pressure gas is stored in the high-pressure air chamber (31); the paddle (33) is connected to the tilting section wing (2) via the rotating shaft (32); the paddle (33) rotates around the rotating shaft (32) to change the direction of a high-speed airflow blown out from the high-pressure air chamber (31); and a gap is left between the paddle (33) and the tilting section wing (2).

2. The drag reduction structure of a tilt-rotor aircraft according to claim 1, characterized in that: The tilt mechanism is composed of a driving gear (8), a steering gear (9), a driven gear (10), and a tilt shaft (11); the steering gear (9) and the driving gear (8) are installed in combination in the tilt section wing (2); the driven gear (10) is connected to the fixed section wing (1) through the tilt shaft (11); the driven gear (10) is meshed with the driving gear (8); the tilt mechanism rotates to drive the tilt section wing (2) to tilt relative to the fixed section wing (1), thereby realizing the conversion of the aircraft between the fixed wing mode and the helicopter mode.

3. The drag reduction structure of a tilt-rotor aircraft according to claim 1, characterized in that: The power assembly consists of a nacelle (5), a propeller (6) and a fairing (7); the nacelle (5) is arranged below the leading edge of the tilting section wing (2), and a motor is arranged in the nacelle (5).

4. The drag reduction structure of a tilt-rotor aircraft according to claim 3, characterized in that: A propeller (6) is installed at the front end of the nacelle (5) via a hinge device; the fairing (7) is transitionally connected to the lower side of the leading edge of the tilting section wing (2), and the fairing (7) and the propeller (6) are both connected to the motor in the nacelle (5).

5. The drag reduction structure of a tilt-rotor aircraft according to claim 1, characterized in that: The tilting section wing (2) is provided with an aileron (4), and the aileron (4) is movably hinged in a connecting groove provided on the tilting section wing (2).

6. A method for reducing drag of a tilt-rotor aircraft, characterized in that: A drag reduction structure for a tilt-rotor aircraft as claimed in any one of claims 1 to 5, wherein the drag reduction method is as follows: when the aircraft is in helicopter mode, the paddle (33) of the trailing edge blowing mechanism will rotate upward 90 degrees around the rotation axis (32) to blow the high-speed airflow blown out of the high-pressure air chamber (31) along the upper wing surface of the tilt-section wing (2) toward the leading edge of the tilt-section wing (2), so that the airflow on the upper wing surface of the tilt-section wing (2) is separated, thereby reducing the pressure difference between the upper and lower wing surfaces of the tilt-section wing (2), so as to reduce the resistance generated by the high-speed slipstream of the propeller (6) on the tilt-section wing (2).

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