Aerodynamic layout of wide-speed-range variant high-speed aircraft

Abstract

The invention discloses a wide-speed-range variant high-speed aircraft aerodynamic layout, and belongs to the technical field of aircrafts, the wide-speed-range variant high-speed aircraft aerodynamic layout comprises a fuselage, the front end of the fuselage is provided with a drag reduction rod, the rear end is provided with a thrust vectoring nozzle, the left and right sides are symmetrically provided with triangular sweepback wings, and the top is provided with a supporting structure; a high-pressure capturing wing is arranged on the top of the supporting structure. The shock wave separation effect of the drag reduction rod is combined with the high-pressure capture and reflection shock wave induction mechanism of the high-pressure capture wings, so that the aircraft can achieve effective drag reduction and lift augmentation effects in different flight states, and the lift-drag ratio and adaptability of the high-speed blunt cone aircraft are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of aircraft technology, and more particularly to an aerodynamic layout for a wide-speed-range variant high-speed aircraft. Background Technology

[0002] When high-speed aircraft fly at supersonic and hypersonic speeds, their aerodynamic characteristics are mainly affected by flow structures such as strong shock waves and expansion waves. Among these, attached shock waves significantly increase pressure drag, becoming one of the key factors limiting the lift-to-drag ratio and range performance of aircraft. Therefore, how to reduce shock wave drag while maintaining structural volumetric efficiency and simultaneously improve lift is an important research direction in the aerodynamic layout design of high-speed aircraft.

[0003] Currently, high-speed aerodynamic configurations mostly employ blended wing-body or waverider layouts. Waveriders rely on controlled attachment of leading-edge shock waves to achieve an ideal lift-to-drag ratio, but their internal volumetric efficiency is limited. While blended wing-body configurations offer higher effective volume, their lift-to-drag ratio is relatively low at high Mach numbers. Existing configurations struggle to simultaneously achieve both a high lift-to-drag ratio and high volumetric efficiency; therefore, there is an urgent need to propose a novel high-speed aircraft configuration that combines both.

[0004] During high-speed flight, wave coupling inevitably occurs between different parts of an aircraft, such as the fuselage, leading edge, and appendages. In traditional designs, these shock waves and expansion waves primarily manifest as additional drag, leading to a decrease in overall performance. However, by rationally arranging the forebody components, the position, intensity, and shape of the shock waves can be effectively controlled, resulting in drag reduction or local pressure gain under certain conditions, thereby improving overall aerodynamic efficiency.

[0005] To address the issue of excessive drag on the forebody of high-speed blunt-cone aircraft, existing research has shown that installing a drag-reducing rod at the nose can push the leading-edge shock wave away from the wall, creating a forward low-pressure zone and significantly reducing pressure drag. Compared to traditional pointed-cone transition structures, drag-reducing rods not only avoid sacrificing internal fuselage volume but also maintain high volumetric efficiency over a wider design range. To further enhance the effectiveness of the drag-reducing rod, an aerodynamic disk can be installed at its front end. The aerodynamic disk weakens the intensity of the reattached shock wave, making the shock wave structure more curved and gentle, thereby further reducing total drag, especially under supersonic inflow conditions. However, existing drag-reducing rod structures are prone to shock wave asymmetry and reattachment position drift under non-zero angles of attack, leading to a significant decrease in drag reduction performance.

[0006] Besides drag reduction design, lift enhancement is equally crucial for high-speed aircraft. High-pressure capture wings, a configuration that utilizes the high-pressure region behind the leading-edge shock wave for lift enhancement, are typically positioned above the aircraft. This structure can capture the high-pressure gas behind the shock wave and generate additional lift through the pressure difference between the upper and lower surfaces, thereby improving the lift-to-drag ratio. However, high-pressure capture wings have significant design point characteristics. When the angle of attack changes or the incoming flow conditions deviate from the design state, the pressure recovery on the compression surface is insufficient, leading to a decrease in lift enhancement and affecting overall flight performance.

[0007] In summary, the drag reduction rod configuration in the existing technology has insufficient drag reduction performance at non-zero angles of attack, and the high-pressure capture wing has insufficient lift increase when deviating from the design point. Therefore, it is difficult to simultaneously meet the dual requirements of drag reduction and lift increase for high-speed blunt cone aircraft under different flight conditions. Summary of the Invention

[0008] The purpose of this invention is to provide an aerodynamic layout for a wide-range variable high-speed aircraft, which solves the problem that the drag reduction rod configuration in the prior art has insufficient drag reduction performance at non-zero angle of attack, and the high-pressure capture wing has insufficient lift increase when deviating from the design point. Therefore, it is difficult to simultaneously meet the dual requirements of drag reduction and lift increase for high-speed blunt cone aircraft under different flight conditions.

[0009] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0010] The present invention discloses an aerodynamic layout for a wide-speed-range variant high-speed aircraft, including a fuselage, a drag-reducing rod at the front end of the fuselage, a vectoring nozzle at the rear end, triangular swept wings symmetrically arranged on the left and right sides, and a support structure at the top; a high-pressure capture wing is arranged at the top of the support structure.

[0011] The front end of the drag-reducing rod is equipped with an aerodynamic disk for generating a bow-shaped shock wave in the hypersonic incoming flow; the nose of the fuselage forms a shoulder region behind the drag-reducing rod, which is used to reattach the airflow after passing through the bow-shaped shock wave and generate a reattached shock wave; the top surface of the fuselage forms an expansion shape behind the blunt cone head, which is used to generate an expansion beam below the high-pressure capture wing; the high-pressure capture wing simultaneously captures the bow-shaped shock wave generated by the drag-reducing rod and the reattached shock wave generated by the shoulder region of the fuselage, and induces the generation of a reflected shock wave; the nose of the fuselage adopts a blunt cone design, and the drag-reducing rod is configured to rotate in a vertical plane around the center of the blunt cone of the nose of the fuselage so that its axis is aligned with the actual incoming flow direction; the support structure is configured to translate vertically and horizontally, so as to drive the high-pressure capture wing to capture the high-pressure airflow;

[0012] The high-pressure zone is formed on the lower surface of the high-pressure capture wing by the multiple compression of the incoming flow by the bow shock wave, the reattached shock wave and the reflected shock wave. The relatively lower pressure formed on the upper surface in the expansion beam generated on the top of the fuselage generates a significantly increased pressure difference between the upper and lower surfaces, thereby providing additional lift to the hypersonic vehicle to improve the lift-to-drag ratio.

[0013] Furthermore, the semi-cone angle β of the blunt cone satisfies: β≤10°.

[0014] Furthermore, the upper surface cross-section of the rear half of the fuselage smoothly transitions from a semi-circle to a semi-rounded rectangle.

[0015] Furthermore, the lower surface cross-section of the rear half of the fuselage smoothly transitions from a semi-circle to an arc with a larger radius.

[0016] Furthermore, the rear half of the fuselage is deflected downwards by 5° to 10°.

[0017] Furthermore, the pneumatic disc adopts a hemispherical structure.

[0018] Furthermore, the rotation angle α of the drag-reducing rod satisfies: 0°≤α≤20°.

[0019] Furthermore, the leading and trailing edges of the high-pressure capture wing are both designed with sweep angles, and its planar geometric profile is a smooth, continuous curve; the leading and trailing edges of the high-pressure capture wing both adopt a smooth transition structure with rounded corners and tangent to straight lines.

[0020] Furthermore, the surface of the vector nozzle adopts a parabolic shape design, and the nozzle exit direction is parallel to the central axis of the fuselage.

[0021] Furthermore, the support structure is designed with a sweep angle.

[0022] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0023] This invention, a wide-range variator high-speed aircraft aerodynamic layout, achieves active coupling between the shock wave system and the pressure field by coordinating the drag-reducing rod and the high-pressure capture wing. The drag-reducing rod pushes the leading-edge shock wave away from the fuselage surface, creating a low-density region in front of the nose and significantly reducing the intensity of the reattached shock wave, thereby reducing nose pressure drag. The bow-shaped shock wave and reattached shock wave, regulated by the drag-reducing rod, form a high-pressure region located further upstream and concentrated above the fuselage, enabling the high-pressure capture wing to acquire compressed gas with higher capture efficiency. After capturing the high-pressure flow, the high-pressure capture wing further induces reflected shock waves. The multi-shock cooperative compression structure, composed of the drag-reducing rod, the reattached shock wave, and the reflected shock wave induced by the high-pressure capture wing, significantly enhances the high-pressure region generated on the lower surface of the capture wing, achieving a lift gain exceeding that of traditional capture wing layouts. Through the above-mentioned coupling effect, the present invention simultaneously achieves nose drag reduction and upper lift increase, so that the increase in lift and the reduction in drag promote each other. While maintaining the high volume ratio of the blunt cone configuration, it achieves a significant nonlinear improvement in lift-to-drag ratio and has a comprehensive aerodynamic gain effect that is significantly greater than the effect of either of them alone.

[0024] Furthermore, the aerodynamic layout variant mechanism of the wide-speed-range variant high-speed aircraft of this invention is simple and reliable to implement. It can achieve significant aerodynamic performance improvement through only single-degree-of-freedom motions such as translation or rotation, improving adaptability and stability at different angles of attack. At the same time, it reduces structural complexity and implementation cost, expands the applicability of high-speed aircraft in high Mach number and multi-condition missions, and has broad application prospects in the field of aerodynamic shape design of future high-speed aircraft.

[0025] In summary, this invention combines the shock wave separation effect of the drag reduction rod with the high-pressure capture and reflected shock wave induction mechanism of the high-pressure capture wing, enabling the aircraft to achieve effective drag reduction and lift enhancement under different flight conditions, thereby significantly improving the lift-to-drag ratio and adaptability of the high-speed blunt cone aircraft. Attached Figure Description

[0026] The present invention will be further described below with reference to the accompanying drawings.

[0027] Figure 1 This is a schematic diagram of the overall aerodynamic layout of the wide-speed-range variant high-speed aircraft of the present invention;

[0028] Figure 2 Schematic diagram of the design principle for drag reduction and lift enhancement;

[0029] Figure 3 This is a pressure contour map;

[0030] Figure 4 This is a schematic diagram of the extreme positions of the aerodynamic layout of the wide-speed-range variant high-speed aircraft of the present invention;

[0031] Figure 5 This is a top view of the wide-speed-range variant high-speed aircraft of the present invention;

[0032] Figure 6 This is a front view of the wide-speed-range variant high-speed aircraft of the present invention;

[0033] Figure 7 This is a rear view of the wide-speed-range variant high-speed aircraft of the present invention;

[0034] Explanation of reference numerals in the attached diagram: 1. Fuselage; 2. Drag reduction rod; 3. Triangular swept wing; 4. Vector nozzle; 5. High-pressure capture wing; 6. Support structure; 7. Bow-shaped shock wave; 8. Reattached shock wave; 9. Expanding beam; 10. Reflected shock wave; 11. High-pressure region. Detailed Implementation

[0035] like Figure 1 , 6 As shown, an aerodynamic layout for a wide-speed-range variant high-speed aircraft includes a fuselage 1, a drag-reducing rod 2 mounted at the front end of the fuselage 1, a vector nozzle 4 mounted at the rear end, triangular swept wings 3 symmetrically mounted on the left and right sides, and a support structure 6 mounted on the top; a high-pressure capture wing 5 is mounted on the top of the support structure 6.

[0036] like Figure 2 , 3 As shown, the front end of the drag-reducing rod 2 is equipped with an aerodynamic disk for generating a bow-shaped shock wave 7 in the hypersonic incoming flow. Specifically, the high-speed incoming flow first contacts the leading edge of the aerodynamic disk, forming a stable bow-shaped shock wave 7 at its head. This bow-shaped shock wave 7 has a certain shock wave angle, and its envelope can cover the head region of the downstream fuselage 1, preventing the high-speed incoming flow from directly impacting the nose, significantly reducing the nose pressure differential drag, and achieving drag reduction. The aerodynamic disk adopts a hemispherical structure to improve the shock wave morphology, increase the shock wave propulsion distance, and enhance the formation effect of the low-density region. Simultaneously, the hemispherical aerodynamic disk can generate a more uniform and gentle bow-shaped shock wave 7 within a wider Mach number and angle of attack range, avoiding pressure fluctuations caused by shock wave asymmetry, making the drag reduction effect more stable and reliable.

[0037] like Figure 2 , 3 As shown, the nose of the fuselage 1 has a shoulder region formed behind the drag-reducing rod 2, which is used to reattach the airflow after passing through the bow-shaped shock wave 7 and generate a reattached shock wave 8. The top surface of the fuselage 1 has an expanded shape formed behind the blunt conical nose, which is used to generate an expanded beam 9 below the high-pressure capturing wing 5. The high-pressure capturing wing 5 simultaneously captures the bow-shaped shock wave 7 generated by the drag-reducing rod 2 and the reattached shock wave 8 generated by the shoulder region of the fuselage 1, and induces the generation of a reflected shock wave 10.

[0038] The bow shock 7, the reattached shock 8, and the reflected shock 10 compress the incoming flow, forming a high-pressure zone 11 on the lower surface of the high-pressure capture wing 5. The relatively lower pressure formed on the upper surface of the expansion beam 9 generated at the top of the fuselage 1 generates a significantly increased pressure difference between the upper and lower surfaces, thereby providing additional lift to the hypersonic vehicle to improve the lift-to-drag ratio.

[0039] like Figure 1 , 4 As shown in Figures 6 and 7, the nose of the fuselage 1 adopts a blunt cone design and is symmetrically distributed along the central axis of the fuselage 1. The semi-cone angle β of the blunt cone satisfies: β≤10°, in order to reduce the shock wave angle and improve the efficiency of the reflected shock wave 10 induced by the high-pressure capture wing 5. The smaller shock wave angle allows the downward deflection angle of the rear half of the fuselage 1 to be reduced, thereby maintaining a high internal volume ratio while maintaining the lift enhancement effect.

[0040] The upper surface cross-section of the rear half of the fuselage 1 smoothly transitions from a semi-circle to a semi-rounded rectangle, which can prevent the reflected shock wave 10 from impacting the upper surface of the fuselage 1 and forming a high-pressure area, thus ensuring that the lift-enhancing effect of the high-pressure capture wing 5 is not disturbed.

[0041] The lower surface section of the rear half of the fuselage 1 smoothly transitions from a semi-circle to an arc with a larger radius, similar to a waverider structure, to form a stable high-pressure zone; this high-pressure zone is effectively "blocked" by the triangular swept wings 3 on both sides to prevent airflow from overflowing upwards, thereby improving the overall lift.

[0042] The rear half of the fuselage 1 is tilted downwards by 5° to 10°.

[0043] like Figure 4 As shown, the drag-reducing rod 2 is mounted to rotate in a vertical plane around the center of the blunt cone at the nose of the fuselage 1, ensuring its axis is aligned with the actual incoming flow direction. The rotation is kept smooth to avoid interfering with flight, thus maintaining the drag-reducing effect at different angles of attack. Specifically, the rotation angle is α, which is the same as the incoming flow angle of attack, ensuring the front end of the drag-reducing rod 2 remains parallel to the incoming flow direction. The angle range of α is limited to 0° ≤ α ≤ 20° to prevent over-correction. This method prevents the high-speed incoming flow from directly impacting the lower surface of the nose of the fuselage 1, thereby suppressing the formation of local high-pressure zones and maintaining the drag-reducing effect of the drag-reducing rod 2.

[0044] like Figure 5 As shown, the leading and trailing edges of the high-pressure capture wing 5 are both designed with sweep angles, and its planar geometric profile is a smooth, continuous curve. Since the leading and trailing edges of the high-pressure zone formed on the lower surface of the high-pressure capture wing 5 are elliptical, in order to improve the capture efficiency of the compressed air mass, the leading and trailing edges of the high-pressure capture wing 5 adopt a smooth transition structure with rounded corners and tangent to straight lines.

[0045] like Figure 4 As shown, the support structure 6 is designed with a sweep angle to reduce the additional drag of the structure itself. The support structure 6 is made as thin as possible while meeting structural strength requirements to further reduce shock wave interference and wave drag. Furthermore, the support structure 6 is configured to translate vertically and horizontally to drive the high-pressure capture wing 5 to capture high-pressure airflow. Specifically, the high-pressure capture wing 5 can be adjusted vertically within range a along the support structure 6 and horizontally within range b along the rear generatrix of the fuselage 1, ensuring that its leading edge appropriately intersects with the upstream shock wave under different incoming flow conditions, thereby maximizing the capture of high-pressure fluid behind the shock wave and maintaining lift enhancement.

[0046] like Figure 4 As shown, the vector nozzle 4 has a parabolic surface design, and the nozzle exit direction is parallel to the central axis of the fuselage 1 to reduce thrust loss caused by lateral velocity. The length of the vector nozzle 4 has been optimized so that the nozzle exit is located within the protection range of the tail of the fuselage 1, thereby avoiding high-temperature ablation caused by shock wave impact on the nozzle wall.

[0047] The working process of this invention is as follows:

[0048] When the aircraft flies at hypersonic speeds, the high-speed incoming airflow impacts the aerodynamic disk, generating a bow-shaped shock wave 7. After passing through this shock wave, the airflow impacts the area near the nose shoulder of the fuselage 1, generating a reattached shock wave 8. The high-pressure capture wing 5 located above the fuselage "captures" the bow-shaped shock wave 7 and the reattached shock wave 8, and induces a reflected shock wave 10. After being compressed multiple times by the bow-shaped shock wave 7, the reattached shock wave 8, and the reflected shock wave 10, the incoming airflow will generate a significant high-pressure zone 11 on the lower surface of the high-pressure capture wing 5. The relatively lower pressure formed on the upper surface of the expansion beam 9 generated at the top of the fuselage 1 will generate a significantly increased pressure difference between the upper and lower surfaces. Since the pressure on the upper surface of the high-pressure capture wing 5 is relatively low, a large pressure difference will be formed between the upper and lower surfaces of the capture wing, contributing to the increase of the overall lift and significantly improving its lift-to-drag ratio. During the above process, when the flight state changes, the support structure 6 moves at a constant speed up and down and forward and backward while maintaining flight stability, so that the high-pressure capture wing 5 moves to a new working position and its leading edge intersects with the upstream shock wave again, thereby maintaining stable lift performance; the rotation angle of the drag reduction rod 2 is consistent with the angle of attack of the incoming flow, so that the front end of the drag reduction rod 2 always remains parallel to the direction of the incoming flow, avoiding the high-speed incoming flow from directly hitting the lower surface of the nose of the fuselage 1, thereby suppressing the formation of local high-pressure areas and ensuring the drag reduction effect of the drag reduction rod 2.

[0049] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. An aerodynamic layout for a wide-speed-range variant high-speed aircraft, characterized in that: The fuselage (1) includes a drag-reducing rod (2) at the front end, a vector nozzle (4) at the rear end, triangular swept wings (3) symmetrically arranged on the left and right sides, and a support structure (6) at the top. A high-pressure capture wing (5) is arranged on the top of the support structure (6). The head of the fuselage (1) adopts a blunt cone design. The drag-reducing rod (2) is configured to rotate around the center of the blunt cone at the head of the fuselage (1) in a vertical plane so that its axis is aligned with the actual incoming flow direction. The support structure (6) is configured to translate in the up-down and forward-backward directions so that it drives the high-pressure capture wing (5) to capture the high-pressure airflow. The front end of the drag-reducing rod (2) is provided with an aerodynamic disk for generating a bow-shaped shock wave (7) in the hypersonic incoming flow; the head of the fuselage (1) has a shoulder region formed behind the drag-reducing rod (2) for reattaching the airflow after passing through the bow-shaped shock wave (7) and generating a reattached shock wave (8); the top surface of the fuselage (1) has an expansion shape formed behind the blunt cone head for generating an expansion beam (9) below the high-pressure capture wing (5); the high-pressure capture wing (5) simultaneously captures the bow-shaped shock wave (7) generated by the drag-reducing rod (2) and the reattached shock wave (8) generated by the shoulder region of the fuselage (1), and induces the generation of a reflected shock wave (10). The high-pressure zone (11) is formed on the lower surface of the high-pressure capture wing (5) by the multiple compression of the incoming flow by the bow shock (7), the reattached shock (8) and the reflected shock (10), and a significantly increased pressure difference between the upper and lower surfaces is generated by utilizing the relatively lower pressure formed on the upper surface of the expansion beam (9) generated at the top of the fuselage (1), thereby providing additional lift to the hypersonic vehicle to improve the lift-to-drag ratio.

2. The aerodynamic layout of the wide-speed-range variant high-speed aircraft according to claim 1, characterized in that: The half-cone angle β of the blunt cone satisfies: β≤10°.

3. The aerodynamic layout of the wide-speed-range variant high-speed aircraft according to claim 1, characterized in that: The upper surface cross section of the rear half of the fuselage (1) smoothly transitions from a semi-circle to a semi-rounded rectangle.

4. The aerodynamic layout of the wide-speed-range variant high-speed aircraft according to claim 1, characterized in that: The lower surface section of the rear half of the fuselage (1) smoothly transitions from a semi-circle to an arc with a larger radius.

5. The aerodynamic layout of the wide-speed-range variant high-speed aircraft according to claim 1, characterized in that: The rear half of the fuselage (1) is deflected downwards by 5° to 10°.

6. The aerodynamic layout of the wide-speed-range variant high-speed aircraft according to claim 1, characterized in that: The pneumatic disc adopts a hemispherical structure.

7. The aerodynamic layout of the wide-speed-range variant high-speed aircraft according to claim 1, characterized in that: The rotation angle α of the drag-reducing rod (2) satisfies: 0°≤α≤20°.

8. The aerodynamic layout of the wide-speed-range variant high-speed aircraft according to claim 1, characterized in that: The leading and trailing edges of the high-pressure capture wing (5) are designed with sweep angles, and its planar geometric profile is a smooth continuous curve; the leading and trailing edges of the high-pressure capture wing (5) adopt a smooth transition structure with rounded corners and tangent to straight lines.

9. The aerodynamic layout of the wide-speed-range variant high-speed aircraft according to claim 1, characterized in that: The surface of the vector nozzle (4) is designed with a parabolic shape, and the nozzle outlet direction is parallel to the central axis of the fuselage (1).

10. The aerodynamic layout of the wide-speed-range variant high-speed aircraft according to claim 1, characterized in that: The support structure (6) is designed with a sweep angle.

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