Triangular-layout three-duct tilting electric vertical take-off and landing aircraft

Abstract

The three-duct tilting electric vertical take-off and landing aircraft comprises an aircraft body, the aircraft body adopts a streamline design, and an integrated electric ducted fan fused with the aircraft body is arranged at the rear part of the aircraft body; a duct sealing device is arranged at an inlet and an outlet of the integrated electric ducted fan; left and right wings are arranged on two sides of the fuselage, and left and right tilting electric ducted fans are respectively mounted in the middles of the left and right wings; the three electric ducted fans are arranged in a triangular space; a horizontal tail and a vertical tail are arranged at the tail part of the fuselage, and the horizontal tail and the vertical tail are arranged by adopting an integrated cross-shaped empennage; wing control surfaces are arranged on the rear edges of the left and right wings, a horizontal tail control surface is arranged on the rear edge of the horizontal tail, and a vertical tail control surface is arranged on the rear edge of the vertical tail. The aircraft adopts a combined layout of double tilting ducts and a single fixed fusion duct, so that high stability of vertical take-off and landing, moment self-balance in a transition stage and high aerodynamic efficiency in a cruise stage are realized.

Description

Technical Field

[0001] This invention relates to the field of aerospace and aircraft design technology, specifically to a triangular-layout, three-duct tilt-electric vertical takeoff and landing aircraft. Background Technology

[0002] In recent years, with the development of electric propulsion and lightweight composite materials, vertical takeoff and landing (VTOL) aircraft have become a hot topic in aerospace engineering research. Existing eVTOL aircraft are mainly divided into two categories: one is the multi-rotor type, which has good vertical takeoff and landing capabilities but low forward flight efficiency; the other is the tiltrotor type or tilt-ducted type, which can take off and land vertically and fly horizontally, but has a complex structure and significant aerodynamic interference.

[0003] Traditional tilt-rotor configurations typically employ open-type propellers, which suffer from significant tip vortex interference, high noise, and thrust loss during forward flight. Ducted fans, by incorporating an annular duct outside the propeller, can significantly improve thrust efficiency, reduce noise, and enhance safety. However, existing tilt-rotor ducted fan layouts are mostly symmetrically arranged with two ducts, which can easily lead to pitch moment imbalances during vertical takeoff and landing. Furthermore, in forward flight mode, the non-operating duct generates additional drag, reducing overall aerodynamic efficiency.

[0004] Therefore, how to improve the aerodynamic shape, reduce drag and increase stability in forward flight while ensuring vertical takeoff and landing capabilities has become a key technical challenge in the design of tiltrotor aircraft. Summary of the Invention

[0005] To overcome the problems of high drag during cruise, complex transition flight control, and low thrust redundancy in existing vertical takeoff and landing (VTOL) aircraft, this invention provides a triangular-configured three-duct tilt-type electric vertical takeoff and landing (VTOL) aircraft. This aircraft employs a combined layout of "dual tilt-duct + single fixed duct," achieving high stability during vertical takeoff and landing, torque self-balancing during the transition phase, and high aerodynamic efficiency during cruise.

[0006] The technical solution of the present invention to solve the above problems is as follows: This application provides a triangularly arranged three-ducted tilt-type electric vertical takeoff and landing aircraft, including a fuselage with a streamlined design. An integrated electric ducted fan is installed at the rear of the fuselage. The inlet and outlet of the integrated electric ducted fan are equipped with duct sealing devices. Left and right wings are provided on both sides of the fuselage, and left and right tiltable electric ducted fans are respectively installed in the middle of the left and right wings. The three electric ducted fans are arranged in a triangular spatial arrangement.

[0007] In one alternative embodiment, the left and right tiltable electric ducted fans further include a tilting mechanism, which includes a laterally arranged rotating shaft and a drive device. The left and right tiltable electric ducted fans are mounted in the mounting space of the left and right wings via the rotating shaft.

[0008] In one alternative, the left and right tiltable electric ducted fans are configured to rotate about a transverse axis within a range of 0° to 90°.

[0009] In one alternative configuration, the left and right wings adopt a medium aspect ratio structure, and the left and right tiltable electric ducted fans are mounted on the main beam and connected by reinforced nodes.

[0010] In one alternative, all three electric ducted fans are driven by independent motors.

[0011] In one alternative embodiment, the fuselage is provided with a horizontal stabilizer and a vertical stabilizer at the tail, wherein the horizontal stabilizer and the vertical stabilizer are arranged in an integrated "cross-shaped" tail fin configuration.

[0012] In one alternative embodiment, the trailing edges of both the left and right wings are provided with wing control surfaces, the trailing edge of the horizontal stabilizer is provided with a horizontal stabilizer control surface, and the trailing edge of the vertical stabilizer is provided with a vertical stabilizer control surface.

[0013] In one alternative configuration, landing gear is provided below the fuselage.

[0014] In one alternative approach, the aircraft has four flight modes: Vertical takeoff and landing mode: The duct enclosure is opened, and the three electric duct fans are all in a vertical state and work together to provide the aircraft with all vertical lift and control the attitude through differential speed. Hovering mode: Attitude control is achieved by adjusting the thrust difference of each of the three electric ducted fans; Transition mode: The left and right tiltable electric ducted fans gradually tilt towards a horizontal position; during this process, the integrated electric ducted fan continues to work and adjusts its thrust to balance the nose-down torque generated by the tilting of the left and right tiltable electric ducted fans until the wing aerodynamic lift is fully established; during the establishment of the wing aerodynamic lift, the speed of the integrated electric ducted fan gradually decreases, and the duct sealing device gradually closes; Forward flight mode: When the airspeed reaches the predetermined threshold, the integrated electric ducted fan stops working and the duct sealing device is fully closed; the left and right tiltable electric ducted fans are locked in the horizontal position and only provide cruise thrust, and the lift of the aircraft is provided entirely by the left and right wings, horizontal stabilizer and vertical stabilizer.

[0015] In one alternative embodiment, the duct enclosure is a push-out baffle structure, wherein in the closed state, the outer surface of the duct enclosure is flush with the skin surface of the fuselage, forming a smooth aerodynamic transition surface.

[0016] In summary, the triangular-layout, three-duct tilt-electric vertical takeoff and landing aircraft provided by this invention has the following advantages: (1) By combining the design of the rear ducted fan with the enclosed device, the problem of parasitic drag caused by the exposed vertical motor during cruise of traditional multi-rotor or compound wing aircraft is solved, and the lift-to-drag ratio and range are significantly improved. (2) The use of a rear-mounted lift fan as an "aerodynamic trimmer" effectively solves the problem of drastic pitch moment changes commonly seen in tiltrotor aircraft in transition corridors, and reduces the difficulty of control law design; (3) The triangular layout allows the two front fans to be supported by the wing structure at the same time and converted into propulsion power during cruise, thus avoiding dead weight; the single rear fan focuses on low-speed lift and trim, thus achieving the optimal power distribution. (4) With three independently driven fans and aerodynamic control surfaces, the landing safety can still be ensured by the remaining power and gliding ability when a single power unit fails. Attached Figure Description

[0017] The accompanying drawings, which are provided to further illustrate the invention and constitute a part of this invention, are illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention.

[0018] Figure 1 This is a schematic diagram of the overall structural layout of the aircraft of the present invention; Figure 2 This is a top-view schematic diagram of the vertical takeoff attitude of the aircraft of the present invention; Figure 3 This is a schematic diagram of the tilt transition attitude of the aircraft of the present invention; Figure 4 This is a top-down view of the forward flight attitude of the aircraft of the present invention (with the rear duct closed). Figure 5 This is a forward-looking schematic diagram of the forward flight attitude of the aircraft of the present invention (with the rear duct closed). Figure 6 This is a schematic diagram of the operation of the duct sealing device of the aircraft of the present invention.

[0019] Attached image captions: 1-Fuselage; 2-Integrated electric ducted fan; 3-Left wing; 4-Right wing; 5-Wing control surfaces; 6-Left tiltable electric ducted fan; 7-Right tiltable electric ducted fan; 8-Horizontal stabilizer; 9-Vertical stabilizer; 10-Horizontal stabilizer control surfaces; 11-Vertical stabilizer control surfaces; 12-Duct enclosure; 13-Landing gear. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0021] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0023] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used solely for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In the description of the present invention, unless otherwise stated, "a plurality of" means two or more. Furthermore, the terms "first" and "second" are merely used for descriptive distinction and have no special meaning.

[0024] This invention discloses a triangular-configured, three-duct tilt-electric vertical takeoff and landing aircraft, such as... Figure 1As shown, the aircraft provided by this invention includes a fuselage 1, which adopts a streamlined shape design to reduce aerodynamic drag and improve flight efficiency in forward flight. A landing gear 13 is installed below the fuselage 1 for takeoff and landing. An integrated electric ducted fan 2, fused with the fuselage, is located at the rear of the fuselage 1. This ducted fan is vertically embedded within the structure of the fuselage 1 and provides lift and thrust for vertical takeoff and landing, hovering, and transition phases. Furthermore, a duct sealing device 12 is provided at the inlet and outlet of the ducted fan. Through the integrated design of the rear ducted fan and the cooperation of the sealing device, the parasitic drag problem caused by the exposed vertical motors during cruise in traditional multi-rotor or compound-wing aircraft is solved, significantly improving the lift-to-drag ratio and range.

[0025] Furthermore, left and right wings 3 and 4 are provided on both sides of the fuselage 1, and left and right tiltable electric ducted fans 6 and 7 are provided in the middle of the two wings. The two ducted fans are in a vertical operating state during vertical takeoff and landing and hovering phases to provide lift; during transition and forward flight phases, the two ducted fans are tilted to a horizontal position to provide forward thrust.

[0026] Specifically, the left and right tiltable electric ducted fans 6 and 7 are configured to rotate around the lateral axis within a range of 0° to 90° to achieve switching between vertical lift and horizontal thrust states. The tilting action is automatically completed by the electric drive unit in response to commands from the flight control system, enabling the aircraft to smoothly switch between four flight modes: vertical takeoff and landing, hovering, transition, and forward flight.

[0027] More specifically, the left and right wings 3 and 4 adopt a medium aspect ratio structure, and the left and right tiltable electric ducted fans 6 and 7 are installed at the main beam position, with reinforced joint connections to ensure a stable connection. The left and right tiltable electric ducted fans 6 and 7 also include a tilting mechanism, which includes a laterally arranged rotating shaft and a drive device. The left and right tiltable electric ducted fans 6 and 7 are installed in the installation space of the left and right wings 3 and 4 via the rotating shaft.

[0028] Preferably, the three-ducted fan of the present invention is arranged in a triangular pattern, that is, the two left and right tiltable electric ducted fans 6 and 7 at the front and the integrated electric ducted fan 2 at the rear are symmetrically distributed downwards in the longitudinal direction. The two left and right tiltable electric ducted fans 6 and 7 at the front are responsible for the main thrust output and roll control, while the integrated electric ducted fan 2 at the rear is responsible for auxiliary lift generation and pitch moment balance. This layout can form a balanced thrust distribution during vertical takeoff and landing, avoiding excessive pitch moment; during hovering, the large-spaced power fulcrum effectively improves attitude stability in hovering; during the transition phase, the rear lift fan is used as an "aerodynamic trimmer," effectively solving the problem of drastic pitch moment changes commonly seen in tiltrotor aircraft during the transition corridor; during forward flight, the thrust center and center of gravity are reasonably matched, improving the aerodynamic stability of the entire aircraft, allowing the two front fans to be supported by the wing structure simultaneously and converted into propulsion power during cruise, avoiding dead weight, while the single rear fan focuses on low-speed lift and trim, achieving optimal power distribution.

[0029] In practical applications, the control logic of the aircraft in different modes is as follows: (1) Vertical take-off and landing mode: The duct enclosure device 12 is opened, and the three duct fans 2, 6 and 7 are all in a vertical state (90°) and work together to provide the aircraft with all vertical lift and control the attitude through differential speed. (2) Hovering mode: Attitude control is achieved by adjusting the thrust difference of each ducted fan; (3) Transition mode: The left and right tiltable electric ducted fans 6 and 7 on the wings gradually tilt to the horizontal state (0°); during this process, the integrated electric ducted fan 2 continues to work and adjusts the thrust to balance the nose-down torque generated by the tilting of the left and right tiltable electric ducted fans 6 and 7 until the aerodynamic lift of the wings is fully established; during the process of establishing the aerodynamic lift of the wings, the speed of the integrated electric ducted fan 2 gradually decreases and the duct sealing device 12 gradually closes. (4) Forward flight mode: When the airspeed reaches the predetermined threshold, the integrated electric ducted fan 2 stops working and the duct sealing device 12 is fully closed to reduce drag; the left and right tiltable electric ducted fans 6 and 7 are locked in the horizontal position and only provide cruise thrust, and the lift of the aircraft is entirely provided by the wings and tail.

[0030] Specifically, such as Figure 2 As shown, when the aircraft is in vertical takeoff and landing (VTOL) or hovering mode, the duct enclosure 12 of the integrated electric ducted fan 2 is fully open. The left and right tiltable electric ducted fans 6 and 7 tilt to a vertical position (90°), providing the aircraft with all its lift. At this time, the aircraft can achieve vertical takeoff and landing on the spot or low-speed hovering, with good attitude stability and crosswind resistance.

[0031] Specifically, such as Figure 3 As shown, when the aircraft enters the transition mode, as the aircraft accelerates forward, the left and right wings 3 and 4 generate aerodynamic lift. The left and right tiltable electric ducted fans 6 and 7 gradually tilt from a vertical position (90°) to a horizontal position (0°). During this process, due to the change in the forward thrust vector, a significant change in pitch moment occurs. The integrated electric ducted fan 2 continues to operate, dynamically adjusting the thrust to compensate for the nose-down moment, ensuring a smooth transition of the fuselage attitude during the power conversion process.

[0032] Furthermore, such as Figure 6 As shown, in the transition mode, the ducted enclosure 12 gradually closes the inlet and outlet of the integrated electric ducted fan 2 according to the flight status. At the same time, the integrated electric ducted fan 2 gradually reduces its speed and stops working, so that the aircraft maintains a smooth aerodynamic shape during the thrust conversion process. During this stage, the flight control system adjusts the attitude of the fuselage 1 by adjusting the thrust to achieve a dynamic balance between lift and center of gravity, ensuring a smooth and reliable flight transition.

[0033] Preferably, the duct sealing device 12 is a push-out baffle structure. In the closed state, the outer surface of the duct sealing device 12 is flush with the skin surface of the fuselage 1, forming a smooth aerodynamic transition surface, thereby significantly reducing forward flight aerodynamic drag.

[0034] Specifically, such as Figure 4 and Figure 5 As shown, when the aircraft fully enters forward flight mode, the left and right tiltable electric ducted fans 6 and 7 tilt to a horizontal position (0°) and remain stable, providing all forward thrust; the left and right wings 3 and 4 generate all lift; the integrated electric ducted fan 2 completely stops and the duct enclosure 12 is completely closed. At this time, the aircraft cruises in a fixed-wing mode, with high cruise speed and range efficiency.

[0035] Preferably, the aircraft is equipped with a horizontal stabilizer 8 and a vertical stabilizer 9 at the tail, both arranged in an integrated "cross-shaped" tail configuration to enhance longitudinal and directional stability. The trailing edge of the horizontal stabilizer 8 is equipped with a horizontal stabilizer control surface 10, which is a pitch control surface; the trailing edge of the vertical stabilizer 9 is equipped with a vertical stabilizer control surface 11, which is a directional control surface. These two control surfaces provide pitch and directional control in forward flight, working in conjunction with the ducted fan differential thrust control to ensure excellent attitude stability of the entire aircraft in multiple modes.

[0036] Furthermore, the trailing edges of the left and right wings 3 and 4 are provided with wing control surfaces 5, and the horizontal stabilizer control surface 10, the vertical stabilizer control surface 11 and the wing control surfaces 5 cooperate with each other to provide aerodynamic control torque during the forward flight phase.

[0037] Furthermore, the three electric ducted fans 2, 6, and 7 are all driven by independent motors, and the duct structure improves thrust efficiency and noise suppression performance. The three independently driven ducted fans, together with three types of aerodynamic control surfaces, can still ensure landing safety through residual power and gliding ability when a single power unit fails.

[0038] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following claims.

[0039] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A triangular-configured, three-duct tilt-electric vertical takeoff and landing aircraft, characterized in that, The fuselage (1) is streamlined and has an integrated electric ducted fan (2) integrated with the fuselage at its rear. The inlet and outlet of the integrated electric ducted fan (2) are equipped with duct sealing devices (12). The fuselage (1) has left and right wings (3, 4) on both sides. The left and right wings (3, 4) are respectively equipped with left and right tiltable electric ducted fans (6, 7) in the middle part of the left and right wings (3, 4). The three electric ducted fans (2, 6, 7) are arranged in a triangular space.

2. The triangular-layout, three-duct tilt-electric vertical takeoff and landing aircraft according to claim 1, characterized in that, The left and right tiltable electric ducted fans (6, 7) also include a tilting mechanism, which includes a laterally arranged rotating shaft and a drive device. The left and right tiltable electric ducted fans (6, 7) are installed in the installation space of the left and right wings (3, 4) through the rotating shaft.

3. The triangular-layout, three-duct tilt-electric vertical takeoff and landing aircraft according to claim 1, characterized in that, The left and right tiltable electric ducted fans (6, 7) are configured to rotate around the transverse axis within a range of 0° to 90°.

4. The triangular-layout, three-duct tilt-electric vertical takeoff and landing aircraft according to claim 1, characterized in that, The left and right wings (3, 4) adopt a medium aspect ratio structure, and the left and right tiltable electric ducted fans (6, 7) are installed at the main beam position and connected by reinforced nodes.

5. The triangular-layout, three-duct tilt-electric vertical takeoff and landing aircraft according to claim 1, characterized in that, The three electric ducted fans (2, 6, 7) are all driven by independent motors.

6. The triangular-layout, three-duct tilt-electric vertical takeoff and landing aircraft according to claim 1, characterized in that, The fuselage (1) is provided with a horizontal tail (8) and a vertical tail (9) at the tail end, and the horizontal tail (8) and the vertical tail (9) are arranged in an integrated "cross-shaped" tail fin.

7. The triangular-layout, three-duct tilt-electric vertical takeoff and landing aircraft according to claim 6, characterized in that, The trailing edges of the left and right wings (3, 4) are provided with wing control surfaces (5), the trailing edge of the horizontal stabilizer (8) is provided with a horizontal stabilizer control surface (10), and the trailing edge of the vertical stabilizer (9) is provided with a vertical stabilizer control surface (11).

8. The triangular-layout, three-duct tilt-electric vertical takeoff and landing aircraft according to claim 1, characterized in that, The fuselage (1) is provided with landing gear (13) below.

9. The triangular-layout, three-duct tilt-electric vertical takeoff and landing aircraft according to claim 6, characterized in that, The aircraft has four flight modes: Vertical take-off and landing mode: The duct enclosure device (12) is opened, and the three electric duct fans (2, 6, 7) are all in a vertical state and work together to provide the aircraft with all vertical lift and control the attitude through differential speed. Hovering mode: Attitude control is achieved by adjusting the thrust difference of each of the three electric ducted fans (2, 6, 7); Transition mode: The left and right tiltable electric ducted fans (6, 7) gradually tilt towards a horizontal state; during this process, the integrated electric ducted fan (2) continues to work and adjusts its thrust to balance the nose-down torque generated by the tilting of the left and right tiltable electric ducted fans (6, 7) until the wing aerodynamic lift is fully established; during the establishment of the wing aerodynamic lift, the speed of the integrated electric ducted fan (2) gradually decreases, and the duct sealing device (12) gradually closes; Forward flight mode: When the airspeed reaches the predetermined threshold, the integrated electric ducted fan (2) stops working and the duct sealing device (12) is completely closed; the left and right tiltable electric ducted fans (6, 7) are locked in the horizontal position and only provide cruise thrust, and the lift of the aircraft is entirely provided by the left and right wings (3, 4), horizontal tail (8) and vertical tail (9).

10. The triangular-layout, three-duct tilt-electric vertical takeoff and landing aircraft according to claim 1, characterized in that, The duct sealing device (12) is a push-out baffle structure. In the closed state, the outer surface of the duct sealing device (12) is flush with the skin surface of the fuselage (1), forming a smooth aerodynamic transition surface.

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