Aerodynamic layout of a large-lift surface ultra-low orbit aircraft

Abstract

The present invention discloses an aerodynamic layout of a large-lift-surface ultra-low-orbit aircraft, which includes an aircraft body, a group of aerodynamic sails, and a group of solar cell wings. The body of the aircraft provides a space for equipment installation, and its cross-section is an equilateral triangle structure with a side length of W and a length of L. The large-lift-surface aerodynamic sails are located directly below the aircraft body, providing the main mechanical load and the area for solar cell placement. The solar cell wings are attached to the upper surface of the aerodynamic sails. The designed large-lift-surface aerodynamic layout can effectively increase the lift-to-drag ratio of the aircraft under the design requirements of a fixed antenna angle, and change the orbital plane of the aircraft through an aerodynamic assist method, so as to achieve a large-range orbital inclination maneuver for the aircraft in the ultra-low orbit with the minimum fuel consumption.

Description

Technical Field

[0001] The present invention relates to an aerodynamic layout of a large-lift-surface ultra-low-orbit aircraft, belonging to the field of aerodynamic design of aerospace aircraft. Background Art

[0002] With the rapid development of space technology, some innovative technologies have been applied to the mission design of spacecraft, including aerodynamic-assisted orbit transfer technology. Aerodynamic-assisted orbit transfer was proposed by Howard London at the annual meeting of the American Institute of Aeronautics and Astronautics in 1961. Aerodynamic-assisted orbit transfer combines pure-impulse orbit transfer with aerodynamic orbit transfer, and inserts an atmospheric flight stage during the entire orbit transfer flight. During this flight segment, part of the orbit transfer (changing the orbit plane or altitude) is completed with the help of aerodynamic force, and finally all orbit transfer requirements are completed with technical indicators such as minimum energy consumption.

[0003] The AOT (Aeroassisted Orbit Transfer) orbit transfer method effectively utilizes the natural resource of the atmosphere around the planet where the spacecraft orbits, reduces fuel consumption with the help of aerodynamic force, and thus enables the aircraft to obtain a larger payload ratio. Since this orbit transfer method can greatly save the fuel required for orbit transfer, it is generally considered that AOT is one of the very important means for future space transportation. The successful flight tests of transatmospheric aircraft such as the space shuttle, CAV, and X-37B have proved the feasibility of aerodynamic-assisted orbit transfer technology, providing technical support and guarantee for the development of new space transportation systems.

[0004] Research has found that to achieve aerodynamic-assisted orbit transfer of a space vehicle, it is necessary to break through the design of a hypersonic fuselage with a high lift-drag ratio. For a hypersonic aircraft with a high lift-drag ratio, when the aircraft operates very close to the vicinity of the maximum hypersonic lift-drag ratio, the aerodynamic maneuver efficiency for changing the orbit plane is the highest, and the key factor for achieving large-scale lateral maneuver is the maximum lift-drag ratio of the aircraft. The effective range is also related to the lift-drag ratio of the aircraft. Therefore, the design of a hypersonic airframe with a high lift-drag ratio is particularly important. Summary of the Invention

[0005] The technical problem solved by the present invention is: to overcome the problem of the relatively small lift-drag ratio of existing aircraft, and provide an aerodynamic layout of a large-lift-surface ultra-low-orbit aircraft, which can greatly improve the aerodynamic lift-drag ratio of the aircraft, thereby improving the maneuvering orbit transfer ability of the aircraft.

[0006] The technical solution of the present invention is:

[0007] An aerodynamic layout of a large-lift-surface ultra-low-orbit aircraft, comprising an aircraft body, an aerodynamic sail, and a solar cell wing; the aircraft body provides an equipment installation space, the large-lift-surface aerodynamic sail is located directly below the aircraft body, and the solar cell wing is attached to the upper surface of the aerodynamic sail.

[0008] In some implementations, when the aircraft body performs aerodynamic orbit transfer, it operates in the deep atmosphere, and the height of the deep atmosphere is below 100 km.

[0009] In some implementations, the cross-section of the aircraft body is an equilateral triangle structure, and the aerodynamic sail is connected to one side of the aircraft body.

[0010] In some implementations, the side length of the equilateral triangle cross-section is W and the length is L, and the value range is: 0.5 m ≤ W ≤ 1.5 m, 5 m ≤ L ≤ 15 m.

[0011] In some implementations, the aerodynamic sail adopts a honeycomb structure, which can not only save the weight of the aerodynamic sail plate but also maintain the rigidity and strength of the aerodynamic sail.

[0012] In some implementations, the aerodynamic sail has an airfoil sweep (the sweep angle is θ L ) shape, which can reduce the pressure drag on the windward side of the aerodynamic sail. The value range of θ L is: 0° < θ L ≤ 60°.

[0013] In some implementations, the root length of the aerodynamic sail wing is L s , the tip length of the wing is L w , and the thickness is W w , and the value range is: 5 m ≤ L s ≤ 15 m, 0.5 m ≤ L w ≤ 5 m, 10 mm ≤ W w ≤ 100 mm.

[0014] In some implementations, the distance between the head of the aircraft body along the flight direction and the vertex of the aerodynamic sail is L1, and the value range is: W ≤ L1 ≤ 5W.

[0015] In some implementations, the solar cell wing is a thin sheet structure and covers the entire upper surface of the aerodynamic sail. The thickness of the solar cell wing is W s , and the value range is: 5 mm ≤ W s ≤ 50 mm.

[0016] In summary, this application includes at least the following beneficial technical effects:

[0017] (1) The aerodynamic layout of a large lift surface ultra-low orbit aircraft provided by the present invention uses a satellite body with an equilateral triangle cross-section as the installation space, which can not only ensure the function of the remote sensing antenna but also effectively reduce the volume of the aircraft, thereby reducing the supersonic wave drag and skin friction of the aircraft.

[0018] (2) The aerodynamic layout of a large lift surface ultra-low orbit aircraft provided by the present invention not only has an aerodynamic sail to provide lift for the aircraft, but also can provide an area for arranging solar cells, and has the function of power generation by solar wings.

[0019] (3) The overall structure of the present invention is simpler, with low economic cost and great economic value. Description of the Drawings

[0020] Figure 1 : Schematic diagram of the large lift surface ultra-low orbit aircraft of the present invention;

[0021] Figure 2 : Front view of the aerodynamic layout of the aircraft;

[0022] Figure 3 : Top view of the aerodynamic layout of the aircraft;

[0023] Figure 4 : Surface pressure contour map of the large lift surface ultra-low orbit aircraft;

[0024] Figure 5 : Variation of lift-drag ratio with angle of attack.

[0025] Description of reference numerals: 1. Aircraft body; 2. Aerodynamic sail; 3. Solar cell wing. Detailed Description of the Invention

[0026] The following further describes the present application in detail with reference to the drawings and specific embodiments:

[0027] An embodiment of the present application discloses an aerodynamic layout of a large lift surface ultra-low orbit aircraft, as Figures 1-3 shown, including an aircraft body 1, an aerodynamic sail 2 and a solar cell wing 3.

[0028] The aircraft body 1 is a prismatic structure with an equilateral triangle cross-section, which can not only meet remote sensing detection but also provide an equipment installation space. The aerodynamic sail 2 is located directly below the aircraft body 1, and the solar cell wing 3 is attached to the upper surface of the aerodynamic sail 2. The aerodynamic sail 2 provides lift for the ultra-low orbit flight of the aircraft and the main mechanical load, and at the same time can provide an area for arranging solar cells to ensure the power generation function of the solar cell wing 3.

[0029] The aircraft operates at a deep space altitude below 100 km.

[0030] The cross-section of the aircraft body is an equilateral triangle structure, and the aerodynamic sail is connected to the side surface of the aircraft body through a connection structure.

[0031] The side length of the equilateral triangle cross-section of the aircraft body is W and the length is L, and the value range is: 0.5 m ≤ W ≤ 1.5 m, 5 m ≤ L ≤ 15 m.

[0032] The pneumatic sail adopts a honeycomb structure, which can not only save the weight of the pneumatic sail plate material, but also maintain the rigidity and strength of the pneumatic sail.

[0033] The pneumatic sail has a swept-back airfoil shape (the swept-back angle is θ L ), which can reduce the pressure drag on the windward side of the pneumatic sail. The value range of θ L is: 0° < θ L ≤ 60°.

[0034] The root length of the pneumatic sail wing is L s , and the tip length is L w , and the thickness is W w . The value range is: 5m ≤ L s ≤ 15m, 0.5m ≤ L w ≤ 5m, 10mm ≤ W w ≤ 100mm.

[0035] The distance between the head of the aircraft body along the flight direction and the vertex of the pneumatic sail is L1, and the value range is: W ≤ L1 ≤ 5W.

[0036] The solar cell wing is a thin sheet structure and covers the entire upper surface of the pneumatic sail. It can not only ensure the power generation function of the solar cell wing, but also achieve the purpose of reducing friction resistance.

[0037] The thickness of the solar cell wing is W s , and the value range is: 5mm ≤ W s ≤ 50mm.

[0038] Embodiment:

[0039] The following combines examples to illustrate the specific implementation of the present invention.

[0040] As a specific design example of the aerodynamic layout of a large lift surface ultra-low orbit aircraft, as Figure 1 shown. In this embodiment, the size of the aircraft body is: length L = 8000mm, side length of the equilateral triangle W = 750mm; the swept-back angle θ of the pneumatic sail = 30°, axial length L S = 8375mm, tip width L w = 4092mm. The flight altitude is taken as 100km, located in the upper atmosphere airspace, and the specific oncoming flow conditions are shown in Table 1.

[0041] Table 1 Oncoming flow conditions of the upper atmosphere aircraft evaluation example

[0042]

[0043] Figure 4It is the surface pressure cloud map of an upper atmosphere aircraft at a flight altitude of 100 km. As can be seen from the figure, the pressure is relatively high on the head of the aircraft body, the solar wings, and the windward side of the antenna. Table 2 shows the aerodynamic drag of a large lift surface ultra-low orbit aircraft at different angles of attack. C L is the lift coefficient, and C D is the drag coefficient.

[0044] Table 2 Lift-to-drag ratio of a large lift surface ultra-low orbit aircraft at different angles of attack

[0045]

[0046]

[0047] As can be seen from Table 2 and Figure 5 it can be seen that at an angle of attack of 10°, the lift-to-drag ratio of the large lift surface ultra-low orbit aircraft is 0.75; at an angle of attack of 20°, the lift-to-drag ratio is 0.85; and at an angle of attack of 30°, the lift-to-drag ratio is 0.81. It can be seen from the table that a large lift surface and an ultra-low orbit aircraft that saves installation space can achieve a relatively high lift-to-drag ratio.

[0048] The implementation principle of this application is as follows:

[0049] Make full use of the equilateral triangle cross-section satellite body as the installation space and also have the function of a remote sensing antenna, which can reduce the surface friction drag and pressure drag brought by additional equipment; use a large-area aerodynamic sail to increase the lift of the satellite, and attach the solar cell wing to the surface of the aerodynamic sail to prevent the gas flow in the gap between the aerodynamic sail and the solar cell wing, further reducing the friction drag brought by the upper surface of the aerodynamic sail and the lower surface of the solar cell wing, so as to achieve a high lift-to-drag ratio of the ultra-low orbit satellite.

[0050] The un-disclosed technology of the present invention belongs to the common general knowledge of those skilled in the art.

[0051] Although the present invention is disclosed above with preferred embodiments, it is not used to limit the present invention. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims of the present invention.

Claims

1. An aerodynamic layout of a large lift surface ultra-low orbit aircraft, characterized in that: It includes an aircraft body (1), an aerodynamic sail (2) and a solar cell wing (3); The aircraft body (1) provides an equipment installation space. The high-lift aerodynamic sail (2) is located directly below the aircraft body (1), and the solar cell wing (3) is attached to the upper surface of the aerodynamic sail (2); The cross-section of the aircraft body (1) is an equilateral triangle structure, and the aerodynamic sail (2) is connected to the side surface of the aircraft body (1) through a connection structure; The pneumatic sail (2) has an airfoil swept shape, and the sweep angle θ of the pneumatic sail (2) L ranges as follows: 0° < θ L ≤ 60°; The root length of the pneumatic sail (2) is L s , and the tip length is L w , and the thickness is W w , and the value range is: 5m ≤ L s ≤ 15m, 0.5m ≤ L w ≤ 5m, 10mm ≤ W w ≤ 100mm.

2. The aerodynamic layout of a large-lift surface ultra-low orbit aircraft according to claim 1, characterized in that: When the aircraft body (1) performs aerodynamic orbit transfer, it operates in the deep atmosphere, and the height of the deep atmosphere is below 100 km.

3. The aerodynamic layout of a large lift surface ultra-low orbit aircraft according to claim 1, characterized in that: The side length of the cross-section of the equilateral triangle structure is W and the length is L, and the value range is: 0.5 m ≤ W ≤ 1.5 m, 5 m ≤ L ≤ 15 m.

4. The aerodynamic layout of a large lift surface ultra-low orbit aircraft according to claim 1, characterized in that: The aerodynamic sail (2) adopts a honeycomb structure.

5. The aerodynamic layout of a large lift surface ultra-low orbit aircraft according to claim 1, characterized in that: The distance between the head of the aircraft body (1) along the flight direction and the vertex of the aerodynamic sail (2) is L1, and the value range is: W ≤ L1 ≤ 5W.

6. The aerodynamic layout of a large-lift surface ultra-low orbit aircraft according to claim 1, characterized in that: The solar cell wing (3) is a thin sheet structure covering the entire upper surface of the aerodynamic sail; the thickness of the solar cell wing is W s , and the value range is: 5 mm ≤ W s ≤ 50 mm.

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