Aerodynamic configuration of wing body fusion layout unmanned aerial vehicle

Abstract

The invention discloses an aerodynamic configuration of a wing body fusion layout unmanned aerial vehicle, and relates to the technical field of high lift-drag ratio flight of low-altitude economic unmanned aerial vehicles, the aerodynamic configuration comprises a wing body part, a V-shaped empennage is mounted at the rear end of the upper surface of the wing body part, and an engine is mounted between the opposite surfaces of the V-shaped empennage; control surface parts are mounted on the wing body part and the V-shaped empennage; an undercarriage is mounted on the lower surface of the wing body part; the wing body part comprises an inner wing and an outer wing, the inner wing and the outer wing are symmetrically arranged, and a wing tip is mounted on the edge of the outer wing; the sweepback angle of the front edge of the wing body part is 20 degrees, and the sweepback angle of the rear edge of the wing body part is 17 degrees. According to the aerodynamic configuration of the wing body fusion layout unmanned aerial vehicle, better aerodynamic performance, higher carrying capacity and lower noise are achieved; the cruising device is simple in appearance, high in cruising efficiency and suitable for engineering practical application.

Description

Technical Field

[0001] The invention relates to the technical field of low-altitude economical unmanned aerial vehicle (UAV) with high lift-to-drag ratio flight, and in particular to an aerodynamic shape of a UAV with a wing-body fusion layout. Background Art

[0002] Since the birth of the aircraft, how to reduce flight resistance, improve flight performance, and reduce structural weight has always been the direction of continuous research in the aviation industry. The Blended Wing Body (BWB) aircraft was first proposed by NASA's Langley Research Center in the 1990s. Due to its highly integrated characteristics in layout, the wetted area is much smaller than that of traditional layout aircraft, which greatly reduces resistance and improves lift-to-drag ratio, so it has better aerodynamic characteristics. In addition, BWB aircraft has potential huge advantages in flight performance, structural weight, safety performance, environmental protection and comfort, and has received extensive attention and in-depth research from domestic and foreign aircraft manufacturers and researchers. Countries with relatively developed aviation industries such as the United States, Europe, and Russia have successively invested a lot of resources in the research of wing-body blended aircraft and have made great progress.

[0003] The BWB UAV is very suitable as the first choice for transportation and long-endurance missions due to its high lift-to-drag ratio. Therefore, the development of a BWB UAV has very clear usage scenarios and requirements for both military and civilian use. In military use, it can undertake reconnaissance, transportation, bombing and other tasks, and in civilian use, it can undertake aerial photography, mapping, express delivery and other businesses.

[0004] The aerodynamic shape of the BWB UAV is characterized by its smoothly transitioned wings and fuselage. Unlike conventional layout aircraft, the aerodynamic shape of its fuselage is also formed by swept wing profiles, so its fuselage can also generate greater lift to achieve a greater lift-to-drag ratio and higher aerodynamic efficiency than conventional layouts.

[0005] How to develop an aerodynamic shape for a wing-body fusion layout UAV so that it can give full play to the advantages of high lift-to-drag ratio and improve its stability in cruising state has become a technical problem that needs to be solved urgently by technicians in this field. Summary of the invention

[0006] The purpose of the present invention is to provide an aerodynamic shape of a wing-body fusion layout UAV to solve the problems listed in the background technology.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0008] The present invention discloses an aerodynamic shape of a wing-body fusion layout UAV, comprising a wing-body part, a V-shaped tail wing is installed at the rear end of the upper surface of the wing-body part, an engine is installed between the opposite surfaces of the V-shaped tail wing, and a control surface part is installed on both the wing-body part and the V-shaped tail wing; a landing gear is installed on the lower surface of the wing-body part;

[0009] The wing-body part comprises an inner wing and an outer wing, wherein the inner wing is symmetrically arranged with the outer wing, and a wing tip is installed at the edge of the outer wing;

[0010] The leading edge sweep angle of the wing-body part is 20°, and the trailing edge sweep angle of the wing-body part is 17°.

[0011] Preferably, the wing-body part is generated using three sections and three guide lines, with the midpoint of the leading edge as the coordinate origin (0, 0, 0) mm, and the wing tip is extended to the point (1520, 265, 2187.5) mm on the basis of the outer wing to be closed.

[0012] Preferably, the three cross sections of the wing-body portion are located at 0, 1250, and 2062.5 mm in the span direction, respectively;

[0013] The cross-sectional airfoil of the wing-fuselage part at 0 mm in the span direction is MH91, which is proportionally scaled to a chord length of 2000 mm, and a blunt trailing edge with a height of 10 mm is intercepted. The leading edge point of the airfoil of the wing-fuselage part is the origin (0, 0, 0) mm;

[0014] The cross-sectional airfoil of the wing-fuselage portion at 1250 mm in the span direction is ONERAOA209, which is proportionally reduced to a chord length of 450 mm, the leading edge points of the airfoil are (950, 100, 1250) mm, and the airfoil is twisted -1° around the Z axis at 1 / 4 of the chord length and -4° around the X axis;

[0015] The cross-sectional airfoil of the wing-fuselage portion located at 2062.5 mm in the span direction is a self-designed airfoil, scaled proportionally to a chord length of 250 mm, the leading edge points of the airfoil are (1250, 190, 2062.5) mm, and the airfoil is twisted 2° around the Z axis at 1 / 4 of the chord length and -21° around the X axis.

[0016] Preferably, the overall geometric parameters of the wing-body part include wingspan b = 4.375m; wing area S = 2.08m 2 ; Aspect ratio A = 9.2; Wing root chord length C r =0.758m; average aerodynamic chord length C a =0.546m; root-tip ratio λ=0.33; 1 / 4 chord sweep angle Λ=17°.

[0017] Preferably, the V-shaped tail is generated by using two cross sections, and the wing tip of the V-shaped tail is extended by 60 mm on the basis of the main part of the V-shaped tail and generated in a closed manner;

[0018] The vertical tail height of the V-shaped tail is 700 mm; the wing root chord length is 492 mm; the leading edge sweep angle is 28°; and the root-tip ratio is 0.3.

[0019] Preferably, the two cross sections of the V-shaped tail are located at 0 and 640 mm in the span direction respectively;

[0020] The cross-sectional airfoil of the V-shaped tail wing at 0 mm in the span direction is NACA0008, which is proportionally scaled to a chord length of 492 mm;

[0021] The cross-sectional airfoil of the V-shaped tail located at 640 mm in the span direction is NACA0008, which is proportionally scaled to a chord length of 147.6 mm, and the leading edge point of the airfoil of the V-shaped tail is (300, 640, 0);

[0022] The V-shaped tail wing as a whole is first rotated -2° around the Y axis, then rotated 41.7° around the X axis, and finally translated to the coordinates of the leading edge point of the wing root of the V-shaped tail wing (1300, 0, 300) mm.

[0023] Preferably, the geometric parameters of the V-shaped tail include: horizontal projection tail volume is 0.7; vertical projection tail volume is 0.11; wingspan b = 0.64m; wing area S = 0.2045; wing root chord length C r =0.492m; root-tip ratio λ=0.3; V-tail leading edge sweep angle Λ=28°; the angle between the V-tail wing surface and the V-tail symmetry plane θ=41.7°.

[0024] Preferably, the landing gear is divided into a front wheel and two main wheels, the front wheel controls the direction during ground taxiing, and the main wheels bear the main weight and control the brakes.

[0025] Preferably, the control surface portion includes an elevator, a rudder and an aileron, the elevator is located in the middle of the trailing edge, the elevator is 300 mm wide, the elevator is located at the leading edge at X=1600 mm, the designed maximum upward deflection angle of the elevator is 30°, and the designed maximum downward deflection angle of the elevator is 20°;

[0026] The rudder is located on the V-shaped tail, between 192 mm and 640 mm in the span direction of the V-shaped tail, the width of the rudder is 0.3 times the chord length of the corresponding section, and the designed maximum deflection angle of the rudder is plus or minus 20°;

[0027] The aileron is located on the trailing edge of the outer wing, between 1100 mm and 1800 mm of the wing-body portion along the wing span, the width of one end of the aileron is 0.2 times the chord length of the corresponding section, and the width of the other end of the aileron is 0.25 times the chord length of the corresponding section;

[0028] The maximum upward deflection angle of the aileron is designed to be 25°, and the maximum downward deflection angle of the aileron is designed to be 20°.

[0029] Compared with the prior art, the beneficial technical effects of the present invention are:

[0030] The aerodynamic shape of the wing-body fusion layout UAV of the present invention has significant technical advantages over conventional layout aircraft. It has higher aerodynamic efficiency, lower fuel consumption, greater internal space utilization and lower noise level. Starting from its higher aerodynamic efficiency, its characteristics are fully utilized in the design to achieve a larger lift-to-drag ratio, optimize the internal space, and achieve a larger load-bearing volume. At the same time, a V-shaped tail is added on the basis of the wing and body to improve flight stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention will be further described below in conjunction with the accompanying drawings.

[0032] Figure 1 A top view of the aerodynamic shape of a wing-body fusion layout UAV of the present invention Figure 1 ;

[0033] Figure 2 A top view of the aerodynamic shape of a wing-body fusion layout UAV of the present invention Figure 2 ;

[0034] Figure 3 A schematic side view of the aerodynamic shape of a wing-body fusion layout UAV of the present invention;

[0035] Figure 4 The wing-body airfoil shape and position of the present invention.

[0036] Explanation of the reference numerals: 1. wing-fuselage; 2. V-shaped tail; 3. control surface part; 4. engine; 5. landing gear part; 6. inner wing; 7. outer wing; 8. wingtip; 9. leading edge; 10. trailing edge; 11. elevator; 12. rudder; 13. aileron; 14. front wheel; 15. main wheel. DETAILED DESCRIPTION

[0037] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0038] like Figure 1-4 As shown, an aerodynamic shape of a wing-body fusion layout UAV includes a wing-body portion 1, a V-shaped tail 2 is installed at the rear end of the upper surface of the wing-body portion 1, an engine 4 is installed between the opposite surfaces of the V-shaped tail 2, and a control surface portion 3 is installed on both the wing-body portion 1 and the V-shaped tail 2; a landing gear 5 is installed on the lower surface of the wing-body portion 1;

[0039] The wing-body part 1 comprises an inner wing 6 and an outer wing 7, wherein the inner wing 6 is symmetrically arranged with the outer wing 7, and a wing tip 8 is installed at the edge of the outer wing 7;

[0040] The leading edge 9 of the wing-fuselage part 1 has a sweep angle of 20°, and the trailing edge 10 of the wing-fuselage part 1 has a sweep angle of 17°.

[0041] Specifically, the wing-body part 1 is generated using three sections and three guide lines, with the midpoint of the leading edge 9 as the coordinate origin (0, 0, 0) mm, and the wing tip 8 is extended to the point (1520, 265, 2187.5) mm on the basis of the outer wing 7 to be closed and generated. The fuselage symmetry plane is 1972 mm long and 303 mm thick, with no obvious winglets, and the entire wing-body part is gradually reversed.

[0042] like Figure 4 As shown, the three cross sections of the wing-body portion 1 are located at 0, 1250, and 2062.5 mm in the span direction respectively;

[0043] The cross-sectional airfoil of the wing-fuselage part 1 at 0 mm in the span direction is MH91, which is proportionally scaled to a chord length of 2000 mm, and a blunt trailing edge with a height of 10 mm is intercepted, so that the actual length of the fuselage is 1972 mm, and the leading edge point of the airfoil of the wing-fuselage part 1 is the origin 0, 0, 0 mm;

[0044] The cross-sectional airfoil of the wing-fuselage portion 1 at 1250 mm in the span direction is ONERA OA209, proportionally reduced to a chord length of 450 mm, the leading edge points of the airfoil are (950, 100, 1250) mm, and the airfoil is twisted -1° around the Z axis at 1 / 4 of the chord length and -4° around the X axis;

[0045] The cross-sectional airfoil of the wing-fuselage portion 1 located at 2062.5 mm in the span direction is a self-designed airfoil, scaled proportionally to a chord length of 250 mm, the leading edge points of the airfoil are (1250, 190, 2062.5) mm, and the airfoil is twisted 2° around the Z axis at 1 / 4 of the chord length and -21° around the X axis.

[0046] Specifically, the overall geometric parameters of the wing-body part 1 include wingspan b=4.375m; wing area S=2.08m 2 ; Aspect ratio A = 9.2; Wing root chord length C r =0.758m; average aerodynamic chord length Ca =0.546m; root-tip ratio λ=0.33; 1 / 4 chord sweep angle Λ=17°.

[0047] Specifically, the V-shaped tail 2 is generated by using two cross sections, and the wing tip of the V-shaped tail 2 is extended by 60 mm on the basis of the main part of the V-shaped tail 2 and is generated in a closed manner;

[0048] The vertical tail height of the V-shaped tail 2 is 700 mm; the wing root chord length is 492 mm; the leading edge sweep angle is 28°; and the root-tip ratio is 0.3.

[0049] Specifically, the two cross sections of the V-shaped tail wing 2 are located at 0 and 640 mm in the span direction respectively;

[0050] The cross-sectional airfoil of the V-shaped tail wing 2 at 0 mm in the span direction is NACA0008, which is proportionally scaled to a chord length of 492 mm;

[0051] The cross-sectional airfoil of the V-shaped tail 2 at 640 mm in the span direction is NACA0008, which is proportionally scaled to a chord length of 147.6 mm, and the leading edge point of the airfoil of the V-shaped tail 2 is (300, 640, 0);

[0052] The V-shaped tail 2 as a whole is first rotated by -2° around the Y axis, then rotated by 41.7° around the X axis, and finally translated to the coordinates of the leading edge point of the wing root of the V-shaped tail 2 at (1300, 0, 300) mm.

[0053] Specifically, the geometric parameters of the V-shaped tail 2 include: horizontal projection tail volume is 0.7; vertical projection tail volume is 0.11; wingspan b = 0.64m; wing area S = 0.2045; wing root chord length C r =0.492m; root-tip ratio λ=0.3; V-tail leading edge sweep angle Λ=28°; the angle between the V-tail wing surface and the V-tail symmetry plane θ=41.7°.

[0054] Specifically, the landing gear 5 is divided into a front wheel 14 and two main wheels 15. The front wheel 14 controls the direction when sliding on the ground, and the main wheel 15 bears the main weight and controls the brakes. The design weight of the UAV is 100 kg, and the center of gravity is set to (870, 0, 0) mm. The design makes the main wheels bear 90% of the weight in a static state; the design limit ground friction angle is greater than or equal to 13.5°; the design center of gravity to a main wheel and the front wheel The angle between the vertical line and the ground is greater than or equal to 50°, and the coordinates of the front wheel contact point with the ground are (240, -250, 0) mm, and the coordinates of the main landing gear wheel contact point with the ground are (940, -240, 300) mm.

[0055] Specifically, the engine is planned to use a turbojet engine and be installed in a back-supported manner. The outer shell needs to ensure that there is enough space inside. The initial plan is to adopt a power scheme with a thrust-to-weight ratio of 0.3. The power of each engine needs to reach about 15kg, and the corresponding engine size is approximately 100mm in diameter and 250mm in length. In order to make the air inlet perpendicular to the flow on the upper surface of the fuselage, the installation angle between the pod and the X-axis is 5°, and the coordinates of the center point of the engine air inlet are (1305.23, 189.77, 200) mm.

[0056] Specifically, the control surface part 3 includes an elevator 11, a rudder 12 and an aileron 13, the elevator 11 is located in the middle of the trailing edge 10, the elevator 11 is 300 mm wide, the elevator 11 is located at X=1600 mm of the leading edge 9, the designed maximum upward deflection angle of the elevator 11 is 30°, and the designed maximum downward deflection angle of the elevator 11 is 20°;

[0057] The rudder 12 is located on the V-shaped tail 2, between 192 mm and 640 mm in the span direction of the V-shaped tail 2, the width of the rudder 12 is 0.3 times the chord length of the corresponding section, and the designed maximum deflection angle of the rudder 12 is plus or minus 20°;

[0058] The aileron 13 is located on the trailing edge 10 of the outer wing 7, and is located between 1100 mm and 1800 mm of the wing-body portion 1 along the wing span direction. The width of one end of the aileron 13 is 0.2 times the chord length of the corresponding section, and the width of the other end of the aileron 13 is 0.25 times the chord length of the corresponding section.

[0059] The maximum upward deflection angle of the aileron 13 is designed to be 25°, and the maximum downward deflection angle of the aileron 13 is designed to be 20°.

[0060] The core research and development idea of ​​the present invention is: to improve the stability of the cruising state under the premise of achieving a high lift-to-drag ratio; its theoretical basis is computational fluid dynamics and aerodynamics; to achieve this core research and development goal, the design of the wing-body fusion layout UAV needs to be optimized in detail in terms of aerodynamic shape and flight control: first, in aerodynamic design, the lift distribution is optimized and the induced drag is minimized by integrating the wing and the fuselage, and the lift is improved by optimizing the airfoil of the fuselage and the airfoil, as well as the main geometric parameters such as the wing-body aspect ratio, and the pressure difference drag and surface friction drag are reduced, thereby significantly improving the lift-to-drag ratio; secondly, the upturned design is adopted at the wing tip to further reduce the induced drag and improve the aerodynamic efficiency; finally, in terms of flight control, the pitch and yaw stability of the UAV is improved by adding a V-shaped tail design, and the natural rolling stability provided by the wide body shape unique to the wing-body fusion layout is combined to achieve a stable attitude design in the cruising state. In addition, the additional attitude balancing ability provided by the three sets of control surfaces designed further improves the stability of the UAV under different flight conditions.

[0061] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0062] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. An aerodynamic shape of a wing-body fusion layout UAV, including a wing-body part, characterized in that: A V-shaped tail is installed at the rear end of the upper surface of the wing-fuselage part, an engine is installed between the opposite surfaces of the V-shaped tail, and a control surface part is installed on both the wing-fuselage part and the V-shaped tail; a landing gear is installed on the lower surface of the wing-fuselage part; The wing-body part comprises an inner wing and an outer wing, wherein the inner wing is symmetrically arranged with the outer wing, and a wing tip is installed at the edge of the outer wing; The leading edge sweep angle of the wing-body part is 20°, and the trailing edge sweep angle of the wing-body part is 17°.

2. The aerodynamic shape of a wing-body fusion layout UAV according to claim 1 is characterized by: The wing-body part is generated by using three sections and three guide lines, with the midpoint of the leading edge as the coordinate origin (0, 0, 0) mm, and the wing tip is extended to the point (1520, 265, 2187.5) mm on the basis of the outer wing and is generated in a closed manner.

3. The aerodynamic shape of the wing-body fusion layout UAV according to claim 2 is characterized by: The three cross sections of the wing-body part are located at 0, 1250, and 2062.5 mm in the span direction respectively; The cross-sectional airfoil of the wing-fuselage part at 0 mm in the span direction is MH91, which is proportionally scaled to a chord length of 2000 mm, and a blunt trailing edge with a height of 10 mm is intercepted. The leading edge point of the airfoil of the wing-fuselage part is the origin (0, 0, 0) mm; The cross-sectional airfoil of the wing-fuselage portion at 1250 mm in the span direction is ONERAOA209, which is proportionally reduced to a chord length of 450 mm, the leading edge points of the airfoil are (950, 100, 1250) mm, and the airfoil is twisted -1° around the Z axis at 1 / 4 of the chord length and -4° around the X axis; The cross-sectional airfoil of the wing-fuselage portion located at 2062.5 mm in the span direction is a self-designed airfoil, scaled proportionally to a chord length of 250 mm, the leading edge points of the airfoil are (1250, 190, 2062.5) mm, and the airfoil is twisted 2° around the Z axis at 1 / 4 of the chord length and -21° around the X axis.

4. The aerodynamic shape of the wing-body fusion layout UAV according to claim 3 is characterized by: The overall geometric parameters of the wing-body part include wingspan b = 4.375m; wing area S = 2.08m 2 ; Aspect ratio A = 9.2; Wing root chord length C r =0.758m; average aerodynamic chord length C a =0.546m; root-tip ratio λ=0.33; 1 / 4 chord sweep angle Λ=17°.

5. The aerodynamic shape of the wing-body fusion layout UAV according to claim 4 is characterized by: The V-shaped tail wing is generated by using two cross sections, and the wing tip of the V-shaped tail wing is extended by 60mm on the basis of the main part of the V-shaped tail wing and is generated in a closed manner; The vertical tail height of the V-shaped tail is 700 mm; the wing root chord length is 492 mm; the leading edge sweep angle is 28°; and the root-tip ratio is 0.

3.

6. The aerodynamic shape of the wing-body fusion layout UAV according to claim 5 is characterized by: The two cross sections of the V-shaped tail are located at 0 and 640 mm in the span direction respectively; The cross-sectional airfoil of the V-shaped tail wing at 0 mm in the span direction is NACA0008, which is proportionally scaled to a chord length of 492 mm; The cross-sectional airfoil of the V-shaped tail located at 640 mm in the span direction is NACA0008, scaled to a chord length of 147.6 mm, and the leading edge point of the airfoil of the V-shaped tail is (300, 640, 0); The V-shaped tail wing as a whole is first rotated -2° around the Y axis, then rotated 41.7° around the X axis, and finally translated to the coordinates of the leading edge point of the wing root of the V-shaped tail wing (1300, 0, 300) mm.

7. The aerodynamic shape of the wing-body fusion layout UAV according to claim 1 is characterized by: The geometric parameters of the V-shaped tail include: horizontal projection tail volume is 0.7; vertical projection tail volume is 0.11; wingspan b = 0.64m; wing area S = 0.2045; wing root chord length C r =0.492m; root-tip ratio λ=0.3; V-tail leading edge sweep angle Λ=28°; the angle between the V-tail wing surface and the V-tail symmetry plane θ=41.7°.

8. The aerodynamic shape of the wing-body fusion layout UAV according to claim 1 is characterized by: The landing gear is divided into a front wheel and two main wheels. The front wheel controls the direction when sliding on the ground, and the main wheels bear the main weight and control the brakes.

9. The aerodynamic shape of a wing-body fusion layout UAV according to claim 1, characterized in that: The control surface part includes an elevator, a rudder and an aileron, the elevator is located in the middle of the trailing edge, the elevator is 300 mm wide, the elevator is located at the leading edge at X=1600 mm, the designed maximum upward deflection angle of the elevator is 30°, and the designed maximum downward deflection angle of the elevator is 20°; The rudder is located on the V-shaped tail, between 192 mm and 640 mm in the span direction of the V-shaped tail, the width of the rudder is 0.3 times the chord length of the corresponding section, and the designed maximum deflection angle of the rudder is plus or minus 20°; The aileron is located on the trailing edge of the outer wing, between 1100 mm and 1800 mm of the wing-body portion along the wing span, the width of one end of the aileron is 0.2 times the chord length of the corresponding section, and the width of the other end of the aileron is 0.25 times the chord length of the corresponding section; The maximum upward deflection angle of the aileron is designed to be 25°, and the maximum downward deflection angle of the aileron is designed to be 20°.

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