CN219192541U

CN219192541U - Bionic eagle wing tip winglet pneumatic structure

Info

Publication number: CN219192541U
Application number: CN202223295457.9U
Authority: CN
Inventors: 王继明; 姚远; 杨万里; 党铁红; 董明
Original assignee: Shanghai Volant Aerotech Ltd
Current assignee: Shanghai Volant Aerotech Ltd
Priority date: 2022-12-08
Filing date: 2022-12-08
Publication date: 2023-06-16
Anticipated expiration: 2032-12-08

Abstract

The utility model discloses a bionic eagle wing tip winglet aerodynamic structure, which comprises a bionic eagle wing tip winglet, wherein the bionic eagle wing tip winglet is arranged at the wing tip end part of a wing, the bionic eagle wing tip winglet comprises a low-resistance wing tip transition section and a wing, the low-resistance wing tip transition section is connected with the wing tip end part of the wing, the wing is connected with the low-resistance wing tip transition section, the wing is in a bent upward reverse structure, the root chord length of the low-resistance wing tip transition section is set to W1, and the tip chord length is set to W2, wherein W2/W1 is controlled to be 0.6-1. The bionic eagle wing tip winglet provided by the structure can reduce the induced resistance during cruising, increase the lift-drag ratio of the whole aircraft, promote the range of the aircraft and increase the effective load of the aircraft.

Description

Bionic eagle wing tip winglet pneumatic structure

Technical Field

The utility model relates to the technical field of aviation, in particular to a bionic eagle wing tip winglet aerodynamic structure.

Background

eVTOL (Electric Vertical Takeoff and Landing) electric vertical takeoff and landing aircraft development has attracted extensive attention including aerospace businesses, automotive industries, transportation industries, governments, military and academia. Future potential applications for eVTOL relate to a variety of scene modes for urban passenger transport, regional passenger transport, freight transport, personal aircraft, emergency medical services, and the like.

Compared with other vehicles, the eVTOL aircraft is more suitable for future travel ecology, has the potential of becoming a next-generation urban air vehicle no matter on an industrial basis or a technical basis, and has the advantages of high safety, low noise, low manufacturing cost, low operation cost and the like as a novel medium-short-distance air vehicle.

Vertical lift of eVTOL is typically achieved by multiple rotors providing vertical lift. The multi-rotor wing has the functions of vertical take-off, landing, hovering and the like, has low dependence on terrain and good flexibility, but the maximum front flying speed is limited by a plurality of limits; if the aircraft only depends on the vertical propellers to provide lift force and thrust, the efficiency is low; the fixed wing aircraft has higher forward flight speed, but has high requirements on terrain and higher site construction and maintenance cost, so that the lift-drag ratio of the vertical take-off and landing aircraft is improved by combining the advantages of multiple rotors and fixed wings, and the voyage is further improved to become a hot spot for aerodynamic research.

The aerodynamic design of an aircraft is critical to the economic performance of the aircraft. For an electric vertical takeoff and landing aircraft, it is desirable for the aircraft to have a higher efficiency, and more pneumatically, a higher lift-drag ratio (the ratio of the lift of the aircraft to the drag). There are many factors that affect lift-drag ratio, such as laminar flow conditions at the wing surface, wing airfoil and plane parameters.

The energy consumption of the transport aircraft is directly proportional to the resistance when the transport aircraft is cruising and flying, so that the pneumatic drag reduction has great significance for improving the cruising performance of the aircraft and reducing the running cost. About 60% -65% of aerodynamic drag is zero liter drag and about 35% -40% is induced drag when the aircraft cruises and flies, wherein the aerodynamic drag is mainly determined by the wetting area and the flow linearity of the aircraft, and the aerodynamic drag is difficult to further reduce under a certain technical level. The latter is mainly embodied in energy loss caused by wing tip vortex, and the induced resistance can be obviously reduced by weakening the wing tip vortex through the optimal design of the wing tip appearance. The existing electric vertical lifting wing tip device generally adopts a simpler low-resistance wing tip device, the lower wing surface flows to turn over the upper wing surface to roll up wing tip vortex due to the typical three-dimensional effect of the wing tip, and the stronger wing tip vortex causes larger induced resistance.

Disclosure of Invention

The utility model aims to provide a bionic eagle wing tip winglet aerodynamic structure to solve the problems in the background art. In order to achieve the above purpose, the present utility model provides the following technical solutions: the utility model provides a bionical eagle wing tip winglet aerodynamic structure, includes bionical eagle wing tip winglet, bionical eagle wing tip winglet installs in wing tip portion, bionical eagle wing tip winglet includes low resistance wing tip transition section and wing, low resistance wing tip transition section connects the wing tip portion, low resistance wing tip transition section is connected to the wing, the wing is the crooked anti-structure, the root chord length of low resistance wing tip transition section is established to W1, and tip chord length is established to W2, wherein W2/W1 control is at 0.6 ~ 1.

Preferably, the root chord length of the wing is set to be C1, the tip chord length is set to be C2, and the wing tip-to-heel ratio C2/C1 is controlled to be 0.3-1.

Preferably, the wing comprises a front wing, a middle wing and a rear wing, and the front wing, the middle wing and the rear wing are distributed in a staggered manner.

Preferably, the dihedral angles in front of, in the wing and behind the wing are gradually decreased in the airflow direction.

Preferably, the wing span before, in and after the wing presents an increasing trend along the airflow direction.

Preferably, the tip chord line of the wing is in a negative torsion state compared with the root chord line, and the torsion angle is controlled to be-3-0 degrees.

The utility model has the technical effects and advantages that: the bionic eagle wing tip winglet provided by the structure can reduce the induced resistance during cruising, increase the lift-drag ratio of the whole aircraft, promote the range of the aircraft and increase the effective load of the aircraft.

Drawings

FIG. 1 is a schematic top view of an installation of the present utility model on an eVTOL aircraft;

FIG. 2 is a front view of a schematic installation view of the present utility model on an eVTOL aircraft;

FIG. 3 is an isometric view of the present utility model on an eVTOL aircraft;

FIG. 4 is a schematic diagram of a simulated hawk wing tip winglet structure according to the utility model;

fig. 5 is a schematic diagram of planar parameters of a simulated hawk wing tip winglet according to the utility model.

In the figure: 1. a body; 2. a motor arm; 3. a wing; 4. an outer V tail; 5. an inner V tail; 6. bionic eagle wing tip winglet; 7. a skid; 61-low resistance wingtip transition section; 62-front of the wing; 63-wing; 64-after the wing.

Detailed Description

In order that the manner in which the above-recited features, advantages, objects and advantages of the present utility model are attained and can be readily understood, a more particular description of the utility model will be rendered by reference to the appended drawings, in which the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected or detachably connected, or integrally or mechanically connected, or electrically connected, unless otherwise explicitly stated and defined; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements.

Examples

As shown in fig. 1, the plane is a top view illustration of an electric vertical take-off and landing plane with a bionic eagle wing tip winglet aerodynamic structure, and main components of the plane comprise a plane body 1, a motor arm 2, a wing 3, an outer V-tail 4, an inner V-tail 5, a bionic eagle wing tip winglet 6 and a skid 7. The bionic eagle wing tip winglet 6 is arranged at the tip end position of the wing 3 (as shown in figures 1 and 2).

The bionic eagle wing tip winglet 6 is similar to the wing after the eagle is unfolded in appearance, and the three-dimensional appearance is shown in an eVTOL aircraft schematic (isometric) diagram containing the bionic eagle wing tip winglet in figure 3 and a structure schematic diagram of the bionic eagle wing tip winglet in figure 4. The bionic eagle wing tip winglet 6 comprises a low-resistance wing tip transition section 61 and wings, wherein the wings comprise a front wing 62, a middle wing 63 and a rear wing 64, and the wings are not limited to 3 wings shown in fig. 4. The wing of the bionic eagle wing tip winglet 6 is characterized in that each wing is bent upwards and is distributed in a staggered manner, and the wake flow of the upstream wing is prevented from influencing the drag reduction effect of the downstream wing. Thus, the direction of the airflow is gradually decreased, but the utility model is not limited thereto, and the dihedral angle of the wing may also be increased in the direction of the airflow.

As shown in FIG. 5, the planar parameters of the bionic eagle wing tip winglet are shown, the chord length of the root of the low-resistance wing tip transition section 61 is set to W1, the chord length of the tip is set to W2, the typical straight low-resistance wing tip part is from the root to the middle, and the W2/W1 is controlled to be 0.6-1. The bionic eagle wing tip winglet 6 starts upwards from the tip of the low resistance wing tip transition section 61 to the wing tip, which is the main section for drag reduction. The chord length of the root part of the wing is C1, the chord length of the tip part is C2, and the ratio of the wing tip to the root of the wing is controlled to be 0.3-1. The wing tip-to-heel ratio can be controlled well to control the strength of wing tip vortex, so that the aim of effectively adjusting the induced resistance is achieved.

The plume length presents an increasing trend along the airflow direction distribution. The increase of the aspect ratio of the bionic eagle wing tip winglet 6 can effectively improve the lift-drag ratio, and the aspect ratio of the upper reverse section is adjusted by controlling the wing height and the ratio of the root chord length and the tip chord length. The lift-drag ratio of the whole aircraft can be improved by improving the height of the wing, but as the height is increased, the bending moment of the wing root is increased, so that the structural weight is increased, and if the height is too large, the comprehensive efficiency is reduced. Meanwhile, too high wing can cause vibration problem, which is unfavorable for structural design.

Due to the induction of wing tip vortices, the local angle of attack of the wing tends to increase compared to the angle of attack of the incoming flow in front, the wing tip chord line is generally negatively twisted compared to the root chord line, i.e. the leading edge is low-headed. The torsion angle is generally controlled to be-3-0 degrees, and the size of the torsion angle is selected to consider not only the full-machine lift-drag ratio in the cruising stage, but also the separation characteristic under a large attack angle. When the front edge of the wing tip is lower, the wing tip is higher, the wing tip deviates from the optimal local attack angle range, namely, the drag reduction effect is reduced when the wing tip is lower, the wing tip can be subjected to flow separation in advance, the wing tip can be subjected to buffeting or non-instruction rolling and other phenomena of an airplane, and the speed loss can be advanced when the wing tip is serious.

Finally, it should be noted that: the foregoing description is only illustrative of the preferred embodiments of the present utility model, and although the present utility model has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described, or equivalents may be substituted for elements thereof, and any modifications, equivalents, improvements or changes may be made without departing from the spirit and principles of the present utility model.

Claims

1. The utility model provides a bionical hawk wing tip winglet aerodynamic structure, includes bionical hawk wing tip winglet, its characterized in that: the bionic eagle wing tip winglet is mounted at the wing tip end part, the bionic eagle wing tip winglet comprises a low-resistance wing tip transition section and a wing, the low-resistance wing tip transition section is connected with the wing tip end part of a wing, the wing is connected with the low-resistance wing tip transition section, the wing is of a bending upward-reverse structure, the root chord length of the low-resistance wing tip transition section is set to W1, the tip chord length is set to W2, and W2/W1 is controlled to be 0.6-1.

2. A simulated hawk wing tip winglet aerodynamic structure as claimed in claim 1, wherein: the chord length of the root part of the wing is set as C1, the chord length of the tip part is set as C2, and the ratio of the wing tip to the root of the wing is controlled to be 0.3-1.

3. A simulated hawk wing tip winglet aerodynamic structure as claimed in claim 1, wherein: the wing comprises a front wing, a middle wing and a rear wing, and the front wing, the middle wing and the rear wing are distributed in a staggered manner.

4. A simulated hawk wing tip winglet aerodynamic structure as claimed in claim 3, wherein: the dihedral angles in front of, in the wing and behind the wing gradually decrease along the airflow direction.

5. A simulated hawk wing tip winglet aerodynamic structure as claimed in claim 3, wherein: the wing span of the front wing, the middle wing and the rear wing of the wing is distributed and presented with increasing trend along the airflow direction.

6. A simulated hawk wing tip winglet aerodynamic structure as claimed in claim 1, wherein: the tip chord line of the wing is in a negative torsion state compared with the root chord line, and the torsion angle is controlled to be-3 degrees to 0 degrees.