CN106516074A - Deformable lift and buoyancy integrated aircraft aerodynamic configuration - Google Patents

Abstract

Belonging to the technical field of aircraft design, the invention discloses a deformable lift and buoyancy integrated aircraft aerodynamic configuration. The aerodynamic configuration has a single-fuselage, tandem wing and horizontal tail-free layout, double vertical tails tilt outward certain angle, wings are located at the upper part of the fuselage, front wings and back wings have the same design. The fuselage can produce radial deformation, the fuselage is divided into a front section, a middle section and a back section, and the three sections of the fuselage deform respectively. Because of the introduction of dynamic lift, the aircraft has higher flight height than an airship, greater flight speed, and stronger wind resistant performance and maneuverability; and due to the introduction of static lift, the aircraft has loading capacity far higher than that of conventional high-altitude unmanned aerial vehicles, and has higher structural height and strength. In the process of vertical rising and fall, the fuselage can produce corresponding deformation to change the fuselage volume so as to guarantee the fuselage lift and the aircraft weight balance. With no need for ballonet and ancillary equipment in conventional airships and lift and buoyancy integrated aircrafts, the deformable lift and buoyancy integrated aircraft aerodynamic configuration provided by the invention can reduce the aircraft weight and decrease the ground parking volume of the aircraft.

Description

A deformable aerodynamic shape of a lift-and-float integrated aircraft

technical field

The invention belongs to the technical field of aircraft design, and relates to a deformable aerodynamic shape of a lift-floating integrated aircraft, in particular to an aerodynamic shape of an aircraft which comprehensively utilizes dynamic lift and static lift and whose fuselage can be adaptively deformed.

Background technique

Near-space flight platforms have broad application prospects. For this kind of high-altitude and long-endurance aircraft platform, high-altitude airships, solar-powered aircraft, and lift-and-float integrated aircraft are currently the most researched directions. But these kinds of aircraft also have their obvious disadvantages: high-altitude airships are too bulky, low flying speed, poor maneuverability, poor wind resistance, and high transportation, storage and maintenance costs. Due to the limitation of solar power, the weight of solar aircraft must be very light, which greatly limits its ability to carry loads, and the body structure has to sacrifice strength and rigidity due to the pursuit of light weight. In order to pursue high aerodynamic efficiency, the wings often use large wings The chord-ratio configuration makes the wing more flexible, and the wing deforms severely during flight, which is prone to flight safety problems. At present, the static lift components of the integrated aircraft are mostly semi-rigid airship structures, and their shape cannot be changed. There must be a huge auxiliary airbag inside to store air to adjust the weight of the aircraft. The ground parking volume is huge, and there must be equipment such as intake and exhaust pumps to adjust The auxiliary airbag has a complex structure and a large additional weight.

In order to overcome the respective shortcomings of the above aircrafts, it is necessary to design an aerodynamic shape of a near-space aircraft with strong load capacity, high structural rigidity, and high aerodynamic efficiency to meet the design requirements of high-altitude and long-endurance UAVs.

Contents of the invention

In order to solve the deficiencies of the near-space aircraft in the prior art, the present invention proposes a deformable aerodynamic shape of the lift-floating integrated aircraft. The main feature of the present invention is that the lift force of the aircraft is composed of static lift force and dynamic lift force. The static lift force or buoyancy force is generated by the fuselage, and the dynamic lift force is generated by the wings. The fuselage can be adaptively deformed with the flight height. Tandem wings, no horizontal tail layout, double vertical tails tilted at a certain angle, the wings are located on the upper part of the fuselage, the front and rear wings are of the same design, the single wing is a straight wing with a large aspect ratio, and the fuselage section is two semi-elliptical combination. The fuselage can produce radial deformation. The fuselage is divided into three sections, front, middle and rear. The deformation of the three sections of the fuselage is carried out separately, and the deformation of the middle section of the fuselage is the main deformation.

The aerodynamic shape of the deformable lifting and floating integrated aircraft provided by the present invention includes a fuselage, a front wing, a rear wing and an empennage. Material Skinning.

The deformable rigid skeleton includes front and rear wing spars, fuselage deformable trusses, fuselage dimensional frames and fuselage longitudinal beams, wherein the fuselage longitudinal beams have two, connected to the front wing spars at two points A and B, It is connected with the rear wing spar at two points C and D; the two ends of the longitudinal beam of the fuselage reach the head and tail of the fuselage as the longitudinal frame support of the fuselage; the deformed truss of the fuselage has two, respectively The front spar is connected at two points A and B, and is connected with the rear wing spar at two points C and D; the two ends of the fuselage dimensional frame are connected with the two longitudinal beams of the fuselage through two rotating pairs , in the front, middle and rear sections of the fuselage, each section of the fuselage has at least one fuselage-dimensional frame, the fuselage-dimensional frame has the same deformation structure as the fuselage deformation truss, the plane where the fuselage The planes where the deformed trusses are located are all perpendicular to the longitudinal beams of the fuselage. In the maximum unfolded state of the fuselage, the shape of the skin structure is consistent with the shape of the designed fuselage.

Both the fuselage deformable truss and the fuselage dimensional frame include five trusses and six revolving pairs. Taking the fuselage deformable truss connected to points A and B on the front wing spar as an example, the fuselage deformable truss Including the first truss to the fifth truss, the structures of the first truss to the fifth truss are all arc-shaped. In the maximum unfolded state, the shape of the skin on the deformed truss of the fuselage is consistent with the shape of the designed fuselage, and the surface of the fuselage The curvature is continuous, and the transition connection is smooth; the truss and one end of the truss are connected at two points A and B respectively through a rotating pair, and the first truss and the fifth truss are sequentially connected to the second truss, the third truss and the fourth truss through a rotating pair. Truss; the outer skin of the fuselage is connected to the first truss to the fifth truss, and deforms together with the first truss to the fifth truss.

The present invention has the following beneficial effects:

(1) The introduction of dynamic lift makes the flying height of the aircraft higher than that of the airship, the flying speed is higher, and the wind resistance and maneuverability are stronger.

(2) The introduction of static lift makes the aircraft's load capacity much higher than that of conventional high-altitude UAVs, and its structural strength is higher.

(3) Since the fuselage can generate part of the static lift, the static lift of the fuselage can be used to achieve vertical take-off and landing at low altitudes, reducing the requirements of the aircraft on the airport, and it can hover within a certain height range at high altitudes, and can complete various fixed points homework tasks.

(4) In the process of vertical ascent and descent, the fuselage can produce corresponding deformation and change the volume of the fuselage to ensure the balance between the buoyancy of the fuselage and the weight of the aircraft. It does not need the secondary airbags and auxiliary equipment in conventional airships and lift-floating integrated aircraft, which can lower the aircraft. reduce the weight of the aircraft on the ground.

Description of drawings

1A-1D are schematic diagrams of the aerodynamic shape of the deformable lift-floating integrated aircraft.

Figure 2 is a schematic diagram of the radial deformation of the fuselage during the ascent process of deformation at low altitude.

Figure 3 is a schematic diagram of the whole machine structure.

Figure 4 is a schematic diagram of the deformed structure of the fuselage.

In the picture:

1-fuselage; 2-front wing; 3-rear wing; 4-tail; 5-engine;

6-solar cell; 7-section shape A; 8-section shape B; 9-section shape C; 10-wing spar;

11-deformation truss of the fuselage; 12-rotating pair; 13-longitudinal beam of the fuselage; 14-dimensional frame of the fuselage.

detailed description

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

The aerodynamic shape of the deformable lift-floating integrated aircraft proposed by the present invention is shown in Figures 1A to 1D. Deformed fuselage, the front wing 2 and the rear wing 3 form front and rear tandem wings, the front wing 2 and the rear wing 3 are both large aspect ratio configurations, and are respectively located at the front and rear of the fuselage 1. Since the rear wing 3 is located at the front In the wake of the wing 2, there is an angle difference of 3° to 6° between the front wing 2 and the rear wing 3 to ensure high aerodynamic efficiency. The empennage 4 adopts a V-shaped tail and is located at the rear of the fuselage 1 . It adopts propeller propulsion, and four engines 5 are respectively placed on the left and right sides of the front and rear wings, and the power supply adopts the joint power supply mode of solar cells 6 and fuel cells. As shown in FIGS. 1B-1D , the grid structure represents solar cells 6 , and the solar cells 6 are laid on the upper surfaces of the fuselage 1 and the front wings 2 and rear wings 3 .

In conjunction with Fig. 1, the aircraft provided by the present invention is a single fuselage, the fuselage adopts a semi-rigid structure, the inside of the fuselage 1 has a deformable rigid skeleton, and a film skin is laid outside the skeleton, and the fuselage 1 is divided into three sections, front, middle and back, as Figure 1B, the front section is a semi-ellipsoidal head, the middle section is a straight section, and the rear section is a tail shrinkage section. The deformation of the three sections of the fuselage is carried out separately, and the deformation of the middle section of the fuselage is the main deformation.

The flight mode of the deformable lift-and-float integrated aircraft: when on the ground, the fuselage 1 of the aircraft has a cross-sectional shape of A7 in the ground state, has the smallest volume, and its static lift and weight are basically balanced. In the rising stage of low-altitude deformation, relying on the engine 5 to generate thrust to overcome the resistance and fly forward, the front wing 2 and the rear wing 3 generate aerodynamic lift to make the aircraft climb, the external atmospheric pressure and atmospheric density decrease, and the internal pressure of the fuselage 1 is greater than the external pressure, forming The pressure difference drives the deformable rigid frame to change without paying extra energy. The volume of the fuselage 1 increases adaptively, keeping the gravity and buoyancy basically equal at all times, and the fuselage section is in the middle state. The fuselage section shape is B8. When the volume of the fuselage 1 increases to the maximum, the deformation ends, the fuselage 1 is the cross-sectional shape C9 when fully expanded, the aircraft reaches the maximum hovering height, and the volume of the fuselage of the aircraft no longer changes. If the aircraft still needs to climb further, it relies on the engine 5 to promote sufficient flight speed, the front wing 2 and the rear wing 3 produce aerodynamic lift, the resultant force of the dynamic lift and buoyancy is greater than the gravity of the aircraft, and the aircraft continues to climb and finally reaches the predetermined cruising altitude. The descending phase is basically the reverse process of the dynamic lift climbing and deformation rising phases. All the energy of the aircraft is provided by the solar cell 6, and the solar cell 6 directly provides energy for the engine 5, airborne equipment and payload during the day, and electrolyzes water to store energy for the fuel cell. Nighttime energy is provided entirely by fuel cells.

In conjunction with Fig. 2, Fig. 3 and Fig. 4, the specific implementation of the deformable rigid frame inside the fuselage is illustrated: as shown in Fig. Dimensional frame 14 and fuselage stringer 13. Wherein there are two fuselage longitudinal beams 13, which are connected at two points A and B with the front wing spar 10, and connected at two points C and D with the rear wing spar 10, and are supported as the longitudinal skeleton of the fuselage. There are two fuselage deformation trusses 11, which are respectively connected with the front and rear wing spars 10. The fuselage deformation truss 11 is a reinforced structure for realizing the deformation of the fuselage. The two ends of the fuselage shape-dimensional frame 14 are connected with the two fuselage longitudinal beams 13 through two rotating pairs, and are respectively arranged on the fuselage. In the front, middle and back three sections of the body, the fuselage dimensional frame 14 has the same deformation structure as the fuselage deformation truss 11, and the plane where the fuselage dimensional frame 14 is located and the plane where the fuselage deformation truss 11 is located are all perpendicular to the longitudinal beam of the fuselage. The maximum unfolded state of the fuselage ensures that the shape of the external skin structure is consistent with the shape of the designed fuselage. Due to the large spatial scale of the fuselage deformation structure, in order to meet the requirements of deformation stability and reduce the mass, the plane rod structure is used to form the fuselage deformation truss 11 and the fuselage shape-dimensional frame 14 . Taking the fuselage deformable truss 11 as an example, the fuselage deformable truss 11 is divided into five truss structures: the first truss H1 to the fifth truss H5, and the five truss structures are all arc-shaped. As shown in Figure 4, the first truss H1 and the fifth H5 are connected to the wing spar 10 through the rotary joint 12, between the first truss H1 and the second truss H2, between the second truss H2 and the third truss H3, and between the third truss The connections between H3 and the fourth truss H4 and between the fourth truss H4 and the fifth truss H5 are respectively connected by a rotating pair 12 . The outer skin of the fuselage is made of film material, laid on the deformable truss 11 of the fuselage, and deformed together with the first truss H1 to the fifth truss H5, the deformable outer surface of the middle part of the fuselage is divided into five pieces, each piece is relatively independent, The block itself does not deform, and the shape and curvature are relatively fixed, so that no large wrinkles will appear during the deformation process, and when the complete deformation is achieved, the curvature of the fuselage surface can be continuous and the transition connection is smooth. The driving force for the deformation of the fuselage deformation truss 11 comes from the pressure difference between the inside and outside of the fuselage skin without paying extra energy. When the deformation is complete, the rotating pair 12 is locked to meet the load-bearing requirements.

When the aircraft is parked on the ground, the fuselage has a cross-sectional shape of A7, as shown in Figure 2. At this time, the first truss H1 and the fifth truss H5 open to both sides of the fuselage, and the third truss H3 moves to the uppermost position. The distance between the four trusses H3 and the wing spar 10 is the smallest; the second truss H2 and the fourth truss H4 are located inside the fuselage, and each rotating pair 12 is locked. At this time, the volume of the fuselage is the smallest, and the transverse dimension is the smallest. During the deformation and ascension process of the aircraft, the fuselage has a cross-sectional shape of B8, and the pressure difference between the inside and outside of the fuselage skin pushes the deformation of the fuselage deformation truss 11 and the fuselage dimensional frame 14 to deform. At this time, the rotating pair 12 is unlocked, and the first truss H1 and The fifth truss H5 rotates around the swivel joint 12 and spreads to both sides of the fuselage, the third truss H3 translates downward, the second truss H2 and the fourth truss H4 rotate downward around the swivel joint 12, and during the deformation process, the auxiliary control device , to ensure the left-right symmetry of the aircraft. As the altitude increases, the volume of the aircraft fuselage gradually increases. When the volume of the fuselage of the aircraft is increased to the maximum state, the fuselage is a cross-sectional shape C9, the third truss H3 is translated to the lowest position, each rotating pair 12 is locked, the first truss H1 and the second truss H2, the second truss H2 and the second truss The three trusses H3, the third truss H3 and the fourth truss H4, the fourth truss H4 and the fifth truss H5 are guaranteed to be tangent, and the transition of the outer skin is smooth.

Example:

The designed maximum hovering height h=15km, the maximum volume V=140000m ³ , and the ratio of the maximum volume to the minimum volume of the fuselage K=6.3.

The chord length of each truss is obtained by calculating the geometric relationship between the deformed trusses: assuming that the distance between the two revolving pairs 12 on the wing spar 10 is a, the chord length of the first truss H1 and the fifth truss H5 is 1.11a, the The chord length of the third truss H3 and the fourth truss H4 is 0.94a, and the chord length of the third truss H3 is 0.85a. Assume that the angle between the first truss H1 and the vertical direction is θ. When the aircraft is parked on the ground, θ=28.4°. During the deformation and ascent process of the aircraft, when the flight altitude is 11km, θ reaches the maximum value of 51.6°. At this time, the truss H2, Both H3 and H4 are in the horizontal position. When the flying height reaches the maximum hovering height of 15km, θ=30.4°, and the deformation is completed.

Claims (5)

1. A deformable lift-floating integrated aircraft aerodynamic shape, comprising fuselage, front wing, rear wing and empennage, is characterized in that: the fuselage is a deformable fuselage, and the inside of the fuselage has a deformable rigid framework, The exterior of the fuselage is covered with thin film material skins; the deformable rigid skeleton includes front and rear wing spars, fuselage deformation trusses, fuselage dimensional frames and fuselage stringers, wherein the fuselage stringers have two, and the front wing The beam is connected at two points A and B, and connected with the rear wing spar at two points C and D; the two ends of the longitudinal beam of the fuselage reach the position of the fuselage head and tail, and are used as the longitudinal frame support of the fuselage; There are two body deformation trusses, which are respectively connected with the front spar at two points A and B, and connected with the rear wing spar at two points C and D; The two longitudinal beams of the fuselage mentioned above are connected. In the front, middle and rear sections of the fuselage, each section of the fuselage has at least one fuselage dimensional frame. The fuselage dimensional frame has the same deformation structure as the fuselage deformation truss. The plane where the body-dimensional frame is located and the plane where the fuselage deformation truss is located are both perpendicular to the longitudinal beam of the fuselage. In the maximum unfolded state of the fuselage, the shape of the skin structure is consistent with the shape of the designed fuselage. 2. The aerodynamic profile of a deformable lifting-floating integrated aircraft according to claim 1, wherein the deformable truss of the fuselage and the dimension-dimensional frame of the fuselage all include five trusses and six rotating pairs, so that The fuselage deformation truss is connected to two points A and B on the front wing spar as an example. The fuselage deformation truss includes the first truss to the fifth truss, and the structures of the first to fifth truss are arc-shaped Shape: In the maximum unfolded state, the shape of the skin on the deformed truss of the fuselage is consistent with the shape of the designed fuselage, the curvature of the fuselage surface is continuous, and the transition connection is smooth; one end of the first truss and the fifth truss are respectively connected to A, At two points B, the first truss and the fifth truss are sequentially connected to the second truss, the third truss and the fourth truss by rotating joints; the outer skin of the fuselage is connected to the first to fifth trusses, The truss to the fifth truss are deformed together. 3. The aerodynamic profile of a deformable lift-floating integrated aircraft according to claim 2, characterized in that: the structural shape and size of the first truss and the fifth truss are the same; the second truss and the fourth truss The structures are identical in shape and size. 4. The aerodynamic profile of a deformable lift-floating integrated aircraft according to claim 2, wherein when the aircraft is parked on the ground, the fuselage has a cross-sectional shape A, and at this moment, the first truss and the fifth truss face toward the fuselage. The two sides are opened, and the third truss moves to the uppermost position. At this time, the distance between the third truss and the wing spar is the smallest; the second truss and the fourth truss are inside the fuselage, and each rotating pair is locked. At this time, the fuselage The volume is the smallest, and the lateral dimension is the smallest; during the deformation and ascension process of the aircraft, the fuselage has a cross-sectional shape of B, and the pressure difference between the inside and outside of the fuselage skin pushes the deformation of the fuselage deformation truss and the fuselage dimensional frame to deform. At this time, the rotating pair is unlocked, and the first The first truss and the fifth truss rotate around the revolving pair and open to the sides of the fuselage, the third truss translates downward, the second and fourth trusses rotate downward around the revolving pair, and the volume of the aircraft fuselage gradually increases; when the aircraft When the volume of the fuselage increases to the maximum state, the fuselage has a cross-sectional shape of C, the third truss moves to the lowest position, and each rotating pair is locked, the first truss and the second truss, the second truss and the third truss, the third truss and The fourth truss, the fourth truss and the fifth truss are guaranteed to be tangent, and the transition of the outer skin is smooth. 5. The aerodynamic profile of a deformable lifting-floating integrated aircraft according to claim 1, wherein in the aircraft, the front wing and the rear wing form front and rear tandem wings, and the front wing and the rear wing are both The large aspect ratio configuration is located at the front and rear of the fuselage respectively. Since the rear wing is located in the wake of the front wing, there is an angle difference of 3° to 6° between the front wing and the rear wing. The empennage adopts a V-shaped empennage. It is located at the rear of the fuselage; it is propelled by propellers, and the four engines are placed on the left and right sides of the front and rear wings respectively, and the power supply is jointly powered by solar cells and fuel cells.