Unmanned aerial vehicle aerodynamic layout and unmanned aerial vehicle

Abstract

The aerodynamic layout comprises a fuselage, wings and an empennage, the wings are installed on the fuselage, the empennage is connected with the wings, the wings comprise a middle wing, outer wings and winglets, the middle wing is connected to the upper end of the middle of the fuselage, the outer wings are symmetrically arranged on the two sides of the middle wing, the winglets are arranged on the edges of the outer wings, the plane shape of the middle wing is rectangular, and the plane shape of the middle wing is rectangular. The plane shape of the outer wing is trapezoid, the sweepback angles of 1 / 4 chord lines of the middle wing and the outer wing are both 0 degree, the dihedral angle of the middle wing is 0 degree, the dihedral angle of the outer wing is 0.5 degree, the empennage comprises a vertical tail and a horizontal tail, and the vertical tail is connected to the wings and arranged behind the fuselage. A stable laminar flow field can be formed in a low-speed cruising state through the combined design of specific structures of the rectangular middle wing and the trapezoidal outer wing, wingspan loads are distributed in an oval trend through the trapezoidal design of the outer wing, induced resistance can be reduced by combining the structural design of the wingtip winglet, and additional resistance caused by the sweepback angle is eliminated through the design that the sweepback angle is 0 degree.

Description

Technical Field

[0001] This utility model relates to the field of unmanned aerial vehicle (UAV) technology, and in particular to the aerodynamic layout of UAVs. Background Technology

[0002] Unmanned aerial vehicles (UAVs) are unmanned aircraft that fly using wireless remote control or autonomous programs. With their advantages of flexible deployment, low cost, and low risk, they have been widely adopted in diverse fields such as military reconnaissance, disaster monitoring, geographic mapping, and express delivery. As application scenarios become more complex, higher demands are being placed on UAVs' endurance, payload efficiency, and environmental adaptability, prompting aircraft design to evolve towards higher efficiency and multi-functionality.

[0003] Aerodynamic layout, as a core aspect of UAV design, directly determines the aerodynamic performance of an aircraft by defining the geometric configuration and relative positions of components such as the fuselage, wings, and tail. A reasonable aerodynamic layout can optimize lift generation, reduce flight drag, enhance handling stability, and influence structural weight distribution and mission payload configuration, thus serving as a key technological foundation for improving the overall flight performance of UAVs. Utility Model Content

[0004] This application provides an aerodynamic layout for an unmanned aerial vehicle (UAV) that enables the UAV to have good flight performance. This application also provides a UAV employing this aerodynamic layout.

[0005] The first aspect of this application provides an aerodynamic layout for an unmanned aerial vehicle (UAV), including:

[0006] body;

[0007] The wing includes: a center wing, an outer wing, and winglets. The center wing is connected to the upper middle part of the fuselage. The outer wings are symmetrically arranged on both sides of the center wing. Winglets are provided on the edges of the outer wings. The planar shape of the center wing is rectangular, and the planar shape of the outer wing is trapezoidal. The sweep angle of the quarter chord of the center wing and the outer wing is 0°. The dihedral angle of the center wing is 0°, and the dihedral angle of the outer wing is 0.5°.

[0008] The tail section includes a vertical stabilizer and a horizontal stabilizer, wherein the vertical stabilizer is connected to the wing and is located at the rear of the fuselage.

[0009] The beneficial effects of the above embodiments are as follows: The combination design of the rectangular center wing and the trapezoidal outer wing can form a stable laminar flow field in low-speed cruise state. The trapezoidal design of the outer wing makes the wingspan load distribution elliptical. Combined with the winglet structure design, it can reduce the generation of induced drag. The design of 0° sweep angle eliminates the additional drag caused by the sweep angle. At the same time, the 0° dihedral angle simplifies the structural complexity and avoids the additional torque generated by asymmetric load. The dihedral angle structure design can improve lateral stability and crosswind resistance. Experimental verification shows that this UAV has good lift performance and flight performance.

[0010] Based on the above embodiments, the embodiments of this application can be further improved as follows:

[0011] In one embodiment of this application, the system further includes: a landing gear bay and a connecting pipe. The landing gear bay is connected to the lower sides of both sides of the mid-wing, and the connecting pipe is connected to the rear end of the landing gear bay. The tail fin is installed at the rear end of the connecting pipe. The beneficial effects of this step are: the landing gear bay is integrated under the mid-wing, and the in-bay design avoids exposed landing gear, thereby reducing parasitic drag; the streamlined transition structure formed by the connecting pipe can guide the wake of the mid-wing to smoothly transition to the tail fin, thereby optimizing aerodynamic efficiency.

[0012] In one embodiment of this application: the outer wing is equipped with flaps and ailerons, the vertical tail is equipped with a rudder, and the horizontal tail is equipped with an elevator.

[0013] In one embodiment of this application: the horizontal stabilizer is positioned above the vertical stabilizer, such that the horizontal stabilizer is located above the rear end of the UAV propeller. The advantage of this step is that it avoids the propeller slipstream area.

[0014] A second aspect of this application provides an unmanned aerial vehicle (UAV) including the aforementioned UAV aerodynamic configuration. Attached Figure Description

[0015] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0016] Figure 1 Diagram I showing the structure of the unmanned aerial vehicle (UAV);

[0017] Figure 2 Diagram II of the UAV structure;

[0018] Figure 3 Diagram III of the UAV structure;

[0019] Figure 4 I is the surface pressure cloud map of the body surface model;

[0020] Figure 5 II. Surface pressure cloud map of the body surface model;

[0021] Figure 6 Surface pressure cloud map III for the body surface model;

[0022] Figure 7 IV is the surface pressure cloud map of the body surface model;

[0023] Figure 8 Figure I shows the aerodynamic characteristic curves.

[0024] Figure 9 Figure II shows the aerodynamic characteristic curves.

[0025] Figure 10 Figure III shows the aerodynamic characteristic curves.

[0026] Figure 11 Figure IV shows the aerodynamic characteristic curves.

[0027] The components are: 1. Fuselage; 2. Wings; 201. Center wing; 202. Outer wing; 203. Winglets; 204. Flaps; 205. Ailerons; 3. Tail; 301. Vertical tail; 302. Horizontal tail; 303. Rudder; 304. Elevator; 4. Landing gear bay; 5. Connecting pipes. Detailed Implementation

[0028] In this application, unless otherwise expressly specified and limited, the terminology used should be interpreted broadly. For example, a connection can be a fixed connection, a detachable connection, or an integral part; it can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of different terms in this utility model according to the specific circumstances, and the scope of the specific meaning should be limited to achieving the function of this application.

[0029] In the description of this application, it should be understood that the directional terms or positional relationships described are based on the orientation or positional relationships shown in the accompanying drawings, or based on the orientation or positional relationships in actual use, and are only for the purpose of facilitating the description of the contents of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0030] Example 1

[0031] like Figure 1-3As shown, an aerodynamic layout for an unmanned aerial vehicle (UAV) includes: a fuselage 1, wings 2, and a tail 3. The wings 2 are mounted on the fuselage 1, and the tail 3 is connected to the wings 2. The wings 2 include: a center wing 201, an outer wing 202, and winglets 203. The center wing 201 is connected to the upper middle part of the fuselage 1. The outer wings 202 are symmetrically arranged on both sides of the center wing 201, and winglets 203 are arranged on the edges of the outer wings 202. The planar shape of the center wing 201 is rectangular, and the planar shape of the outer wing 202 is trapezoidal. The sweep angle of the quarter chord of the center wing 201 and the outer wing 202 is 0°. The dihedral angle of the center wing 201 is 0°, and the dihedral angle of the outer wing 202 is 0.5°. The tail 3 includes: a vertical tail 301 and a horizontal tail 302. The vertical tail 301 is connected to the wings 2 and is located behind the fuselage 1.

[0032] The combination design of the rectangular center wing 201 and the trapezoidal outer wing 202 can form a stable laminar flow field in low-speed cruise. The trapezoidal design of the outer wing 202 makes the wingspan load distribution elliptical. Combined with the winglet 203 structural design, it can reduce the generation of induced drag. The design of 0° sweep angle eliminates the additional drag caused by the sweep angle. At the same time, the 0° dihedral angle simplifies the structural complexity and avoids the additional torque generated by asymmetric load. The dihedral angle structural design can improve lateral stability and crosswind resistance. Experimental verification shows that this UAV has good lift performance and flight performance.

[0033] Among them, such as Figure 1-3 As shown, fuselage 1 has a nacelle configuration and is integrated with the shape of the center wing 201. The engine is mounted at the rear of the nacelle fuselage 1 and is connected to the propeller. An engine cowling is installed at the rear of fuselage 1 and is located on the outside of the engine.

[0034] Among them, such as Figure 1-3 As shown, there are two outer wings 202 symmetrically arranged on both sides of the middle wing 201, two vertical tails 301 symmetrically arranged, and horizontal tails 302 located between the vertical tails 301.

[0035] Among them, such as Figure 1-3 As shown, the aerodynamic layout of the UAV also includes: a landing gear bay 4 and a connecting pipe 5. The landing gear bay 4 is connected to the lower sides of both sides of the middle wing 201, and the connecting pipe 5 is connected to the rear end of the landing gear bay 4. The tail fin 3 is installed at the rear end of the connecting pipe 5. The landing gear bay 4 is integrated under the middle wing 201. Through the internal storage design, the landing gear is not exposed, thereby reducing parasitic drag. The streamlined transition structure formed by the connecting pipe 5 can guide the wake of the middle wing 201 to smoothly transition to the tail fin 3, thereby optimizing aerodynamic efficiency.

[0036] Among them, such as Figure 1-3As shown, the outer wing 202 is equipped with flaps 204 and ailerons 205, the vertical tail 301 is equipped with a rudder 303, and the horizontal tail 302 is equipped with an elevator 304. The flaps 204, ailerons 205, rudder 303, and elevator 304 are all connected to the corresponding servos via linkages, and the servos control the movement of the corresponding elevators 304, flaps 204, ailerons 205, and rudder 303.

[0037] Among them, such as Figure 1-3 As shown, the horizontal stabilizer 302 is positioned above the vertical stabilizer 301, so that the horizontal stabilizer 302 is located above the rear end of the UAV propeller, thereby avoiding the propeller slipstream area.

[0038] The aerodynamic layout also features the following technical parameters: wingspan 8.95m, wing area 4.1m². 2 The wing root chord is 0.65m, the aspect ratio is 18.0, the fuselage length is 3.65m, the overall length is 5.37m, and the overall height (with landing gear down) is 1.39m.

[0039] Aerodynamic characteristics simulation calculations for UAVs:

[0040] The coordinate system for the aerodynamic computation of the UAV carrier platform is defined with the foremost point of the nose as the origin, the X-axis (horizontal and rearward along the longitudinal plane of symmetry of the fuselage) as positive, the Z-axis (upward along the vertical line) as positive, and the Y-axis (defined according to the right-hand rule). STAR CCM+ CFD software is used to simulate the aerodynamic shape of the entire aircraft. The computational mesh is generated based on a structured mesh. The far-field length on the side of the computational domain is taken as 20 times the wingspan, and the far-field lengths at the front, rear, top, and bottom are taken as 20 times the overall aircraft length. The mesh thickness near the wall is 0.01 mm, and the total number of meshes is 12.1 million. The k-ω SST turbulence model is used.

[0041] The aerodynamic characteristics of the entire aircraft were calculated at an altitude of 2000m and at incoming flow velocities of 150km / h and 170km / h, respectively. The reference area of ​​the entire aircraft is 4.5m². 2 The longitudinal reference length is the average aerodynamic chord length of 0.5m, the lateral reference length is the wingspan of 8.95m, and the moment reference points are (2.1m, 0m, 0.25m). The lift coefficient remains almost unchanged at both speeds, while the drag coefficient increases slightly at 120km / h compared to 150km / h. The longitudinal static stability at 120km / h and 150km / h is 0.283 and 0.282, respectively, giving the UAV good flight performance.

[0042] The focal point of the entire machine is located 2.273m behind the origin of the machine head, and the design center of gravity is located at (2.152m, 0m, 0.25m), with a static stability margin of 24.4%. The pressure cloud diagram of the machine body surface is shown below. Figures 4 to 7 .

[0043] The takeoff weight of the UAV platform in this design is set at 320 kg, including 120 kg of usable fuel. When cruising at 150 km / h at an altitude of 2000 m with half fuel, the lift coefficient is 0.626, and the lift-to-drag ratio is approximately 20.12. At an angle of attack of 3-4°, the aircraft achieves its maximum lift-to-drag ratio, approximately 23.2. Aerodynamic characteristic curves are shown below. Figures 8 to 11 .

[0044] Example 2

[0045] An unmanned aerial vehicle (UAV) includes the UAV aerodynamic layout disclosed in Embodiment 1.

[0046] The above are merely embodiments of this utility model. Commonly known structures and characteristics are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are aware of all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can, based on the guidance provided in this application, improve and implement this solution in combination with their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of this utility model. These should also be considered within the scope of protection of this utility model, and will not affect the effectiveness of the implementation of this utility model or the practicality of the patent.

Claims

1. An aerodynamic layout for an unmanned aerial vehicle (UAV), characterized in that, include: body; The wing includes: a center wing, an outer wing, and winglets. The center wing is connected to the upper middle part of the fuselage. The outer wings are symmetrically arranged on both sides of the center wing. Winglets are provided on the edges of the outer wings. The planar shape of the center wing is rectangular, and the planar shape of the outer wing is trapezoidal. The sweep angle of the quarter chord of the center wing and the outer wing is 0°. The dihedral angle of the center wing is 0°, and the dihedral angle of the outer wing is 0.5°. The tail section includes a vertical stabilizer and a horizontal stabilizer, wherein the vertical stabilizer is connected to the wing and is located at the rear of the fuselage.

2. The aerodynamic layout of the unmanned aerial vehicle according to claim 1, characterized in that, Also includes: The landing gear bays and connecting pipes are connected to the lower sides of the center wing. The connecting pipes are connected to the rear end of the landing gear bays, and the tail wing is installed at the rear end of the connecting pipes.

3. The aerodynamic layout of the unmanned aerial vehicle according to claim 1, characterized in that, The outer wing is equipped with flaps and ailerons, the vertical tail is equipped with a rudder, and the horizontal tail is equipped with an elevator.

4. The aerodynamic layout of the unmanned aerial vehicle according to claim 1, characterized in that, The horizontal stabilizer is positioned above the vertical stabilizer, so that the horizontal stabilizer is located above the rear end of the UAV propeller.

5. A drone, characterized in that, The aerodynamic layout of the unmanned aerial vehicle includes any one of claims 1-4.

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