CN113022849A - Propeller and rotor craft - Google Patents
Propeller and rotor craft Download PDFInfo
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- CN113022849A CN113022849A CN202110593820.6A CN202110593820A CN113022849A CN 113022849 A CN113022849 A CN 113022849A CN 202110593820 A CN202110593820 A CN 202110593820A CN 113022849 A CN113022849 A CN 113022849A
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- 238000000034 method Methods 0.000 abstract description 4
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- 230000000694 effects Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
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- 206010035148 Plague Diseases 0.000 description 1
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- 230000009286 beneficial effect Effects 0.000 description 1
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- 238000002474 experimental method Methods 0.000 description 1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C27/00—Rotorcraft; Rotors peculiar thereto
- B64C27/32—Rotors
- B64C27/46—Blades
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C27/00—Rotorcraft; Rotors peculiar thereto
- B64C27/04—Helicopters
- B64C27/08—Helicopters with two or more rotors
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Abstract
The present disclosure relates to a propeller and rotorcraft, wherein the propeller comprises a plurality of blades connected at a center of rotation, and the mounting angle of the blades is 24 ° ± 1.5 ° at a distance from the center of rotation that is 35.7% of the radius of the propeller; the mounting angle of the blade is 16 degrees +/-1.5 degrees at the position 59.5 percent of the radius of the propeller away from the rotation center; the blade mount angle was 12 ° ± 1.5 ° at 83.3% of the radius of the propeller from the center of rotation. The screw that obtains through above-mentioned technical scheme can improve rotor craft's time of flight, journey ability, and then promotes rotor craft aerodynamic efficiency and improves, and under the condition that same lifting surface distributes, required rotational speed is lower for it is possible to reduce the noise that rotor craft flight in-process produced.
Description
Technical Field
The present disclosure relates to the field of aircraft technology, and in particular, to a propeller and rotorcraft.
Background
Many rotor crafts wide application in a plurality of fields such as survey and drawing, security protection, commodity circulation and distribution. Among these, how to improve aerodynamic efficiency and reduce noise is an important issue that plagues rotorcraft design. In the case of rotorcraft, it is necessary to reduce the power consumed as much as possible while generating the same lift, or to generate as much lift as possible while consuming the same power, which is of great importance for increasing the endurance, range and load-carrying capacity of the aircraft. The use experience of the user can be greatly influenced if the noise is too large, and particularly, when the noise is applied to areas with dense population such as logistics distribution, the noise generated by the noise can generate great interference on the daily life of residents, so that the user experience is influenced.
Disclosure of Invention
A first object of the present disclosure is to provide a propeller that can improve the aerodynamic efficiency of a rotorcraft, while reducing the noise level.
To achieve the above object, the present disclosure provides a propeller comprising a plurality of blades connected at a rotation center, the blades having a mount angle of 24 ° ± 1.5 ° at a distance of 35.7% of a radius of the propeller from the rotation center; at 59.5% of the radius of the propeller from the center of rotation, the blade has a setting angle of 16 ° ± 1.5 °; the blade mount angle is 12 ° ± 1.5 ° at 83.3% of the radius of the propeller from the center of rotation.
Optionally, the blade has a stagger angle of 21 ° ± 1.5 ° at 23.8% of the radius of the propeller from the centre of rotation; the blade mount angle is 20 ° ± 1.5 ° at 47.6% of the radius of the propeller from the center of rotation; at 71.4% of the radius of the propeller from the center of rotation, the blade has a setting angle of 14 ° ± 1.5 °; the blade mount angle is 5 ° ± 1.5 ° at a distance of 95.2% of the radius of the propeller from the center of rotation.
Optionally, the relative chord length of the blade is 0.19 ± 0.02 at 35.7% of the radius of the propeller from the centre of rotation; at 59.5% of the radius of the propeller from the centre of rotation, the relative chord length of the blade is 0.13 ± 0.02; the relative chord length of the blade is 0.09 +/-0.02 at the position which is 83.3 percent of the radius of the propeller away from the rotation center, wherein the relative chord length of the blade is the ratio of the local chord length of the blade to the radius of the blade.
Optionally, the relative chord length of the blade is 0.17 ± 0.02 at 23.8% of the radius of the propeller from the centre of rotation; the relative chord length of the blade is 0.16 +/-0.02 at the position which is 47.6 percent of the radius of the propeller away from the rotation center; the relative chord length of the blade is 0.11 plus or minus 0.02 at 71.4% of the radius of the propeller from the center of rotation; the relative chord length of the blade is 0.07 + -0.02 at 95.2% of the radius of the propeller from the center of rotation.
Optionally, the blade has a leading edge and a trailing edge and is formed with a main blade and a blade tip in the span-wise direction, where the leading edge and the trailing edge are swept back.
Optionally, the mounting angle of the blade tip is smaller than the mounting angle of the root of the main blade, the blades are distributed with negative twist from at least the end section of the main blade to the blade tip, and the mounting angle change rate at the blade tip is larger than that at the main blade.
Optionally, the relative chord length of the tip gradually decreases in the spanwise direction, and the relative chord length of the tip is smaller than that of the main paddle.
Optionally, the paddles are three of the same structure.
Optionally, three of the blades are integrally formed and arranged at equal intervals in the circumferential direction.
It is a second object of the present disclosure to provide a rotary-wing aircraft including a propeller according to any of the above.
The propeller provided by the present disclosure comprises a plurality of blades connected at a center of rotation, wherein the mounting angle of the blades is 24 ° ± 1.5 ° at a distance of 35.7% of the radius of the propeller from the center of rotation; the mounting angle of the blade is 16 degrees +/-1.5 degrees at the position 59.5 percent of the radius of the propeller away from the rotation center; the blade mount angle was 12 ° ± 1.5 ° at 83.3% of the radius of the propeller from the center of rotation. The screw that obtains through above-mentioned technical scheme can improve rotor craft's time of flight, journey ability, and then promotes rotor craft aerodynamic efficiency and improves, and under the condition that same lifting surface distributes, required rotational speed is lower for it is possible to reduce the noise that rotor craft flight in-process produced.
Additional features and advantages of the disclosure will be set forth in the detailed description which follows.
Drawings
The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure without limiting the disclosure. In the drawings:
FIG. 1 is a schematic view of a blade provided by an exemplary embodiment of the present disclosure;
FIG. 2 is a schematic view of a propeller provided by an exemplary embodiment of the present disclosure;
FIG. 3 is an illustration of twist angles provided by an exemplary embodiment of the present disclosure;
fig. 4 to 10 are sectional views of the propeller of fig. 2 at different radii from the center of rotation.
Description of the reference numerals
1-blade, 11-main blade, 12-blade tip, 121-sweep, 13-trailing edge, 14-leading edge, 15-chord, 100-propeller.
Detailed Description
The following detailed description of specific embodiments of the present disclosure is provided in connection with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation.
The following detailed description of specific embodiments of the present disclosure is provided in connection with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation. The terms upper and lower equal orientation as presented in this embodiment are with reference to the rotor after it is mounted on the aircraft and the normal operational attitude of the rotorcraft, and should not be considered limiting. The blade for a rotary-wing aircraft of the present disclosure is described in detail below with reference to the accompanying drawings. The features of the following examples and embodiments may be combined with each other without conflict.
It should be noted that the parameters referred to in the present disclosure are defined in a manner common in the art, and the airfoil refers to a two-dimensional section of the blade at any position in the span direction. Taking the blade 1 in fig. 1 as an example, the rotation center is set as the origin to establish a coordinate system, and the extending direction from the root of the main blade 11 to the blade tip 12 is defined as the span direction (left-to-right direction in fig. 1), and correspondingly, the direction perpendicular to the span direction is the chord direction. Wherein C is the local chord length of the airfoil, i.e. the distance from the leading edge 14 to the trailing edge 13 of the airfoil in the standing section; r is the blade radius, i.e., the spanwise distance from the center of rotation to the tip 12 end; dividing the local chord length C by the radius R of the blade, namely C/R is called the relative chord length of the blade and is a dimensionless parameter; r is the spanwise distance from any section airfoil to the center of rotation, and the distance R is divided by the radius R of the blade, namely R/R is called as a spanwise relative position and is a dimensionless parameter. The dimensionless seating parameters used in this disclosure to define the blade profile mean that the shape of the blade 1 is not altered when scaled up or down.
As shown in fig. 1 to 10, the present disclosure provides a propeller 100 including a plurality of blades 1 connected at a rotation center. At 35.7% of the radius of the propeller from the centre of rotation (i.e. R/R = 35.7%), the mounting angle of the blade is 24 ° ± 1.5 °; the mounting angle of the blade is 16 degrees +/-1.5 degrees at the position 59.5 percent of the radius of the propeller away from the rotation center; the blade mount angle was 12 ° ± 1.5 ° at 83.3% of the radius of the propeller from the center of rotation. Referring to fig. 3, the twist angle α refers to the angle between the chord line 15 of the standing section airfoil and the horizontal plane of rotation. The propeller obtained by the technical scheme can improve the time and range capacity of the rotor craft, and further improve the aerodynamic efficiency of the rotor craft. With the same distribution of the lifting surfaces, a lower rotational speed is required, making it possible to reduce the noise generated during the flight of the rotorcraft.
The paddle 1 is further optimized, and the mounting angle of the paddle is 21 degrees +/-1.5 degrees at the position which is 23.8 percent of the radius of the propeller away from the rotation center; the mounting angle of the blade is 20 +/-1.5 degrees at the position which is 47.6 percent of the radius of the propeller away from the rotation center; the mounting angle of the blade is 14 degrees +/-1.5 degrees at the position 71.4% of the radius of the propeller away from the rotation center; the blade mount angle is 5 ° ± 1.5 ° at a distance of 95.2% of the radius of the propeller from the center of rotation.
With continued reference to fig. 1-10, in accordance with an embodiment of the present disclosure, it is possible to obtain better aerodynamic performance and noise reduction through a synergistic optimization of the spanwise distribution of the chord length and stagger angle of the blade 1. Specifically, at a distance of 35.7% of the radius of the propeller from the rotation center, the relative chord length (i.e., C/R) of the blade is 0.19 +/-0.02; at the position 59.5 percent of the radius of the propeller away from the rotation center, the relative chord length of the blade is 0.13 +/-0.02; the relative chord length of the blade is 0.09 ± 0.02 at 83.3% of the radius of the propeller from the center of rotation.
The blade 1 is further optimized, and the relative chord length of the blade is 0.17 +/-0.02 at the position which is 23.8 percent of the radius of the propeller away from the rotation center; the relative chord length of the blade is 0.16 +/-0.02 at the position which is 47.6 percent of the radius of the propeller away from the rotation center; the relative chord length of the blade is 0.11 plus or minus 0.02 at the position 71.4 percent of the radius of the propeller away from the rotation center; the relative chord length of the blade is 0.07 + -0.02 at 95.2% of the radius of the propeller from the center of rotation.
For convenience of description and better in the structure of the blade 1 of the present disclosure, the blade 1 is defined herein as a main blade 11 and a tip 12 from inside to outside in the span-wise direction, and according to one embodiment of the present disclosure, as shown in fig. 1 to 3, the blade 1 is swept back at the tip 12 and the leading edge 14 and the trailing edge 13, that is, a swept-back portion 121 is formed at the tip 12. The backswept part 121 can cut off the air flow in the direction of the blade 1 when the blade 1 rotates, so that the vortex formed by the blade tip 12 is reduced, the strength of the vortex of the blade tip 12 is reduced, and in addition, the backswept part 121 can weaken the degree of air pressure change near the blade 1, weaken the degree of periodic cutting air flow of the blade 1 with certain thickness, and finally reduce the rotation noise generated when the blade 1 rotates. It should be noted here that the leading edge 14 and the trailing edge 13 are both formed in a swept shape, but the degree of sweep may be different. It should be noted that the leading edge 14 and the trailing edge 13 are explained herein according to the knowledge of the ordinary skill in the art.
The blade 1 as a whole may be formed in a negative twist configuration, where negative twist means that the angle of incidence of the tip 12 is smaller than the angle of incidence of the root of the main blade 11. From at least the end part (the end opposite the root) of the main blade 11 to the tip 12, the blade 1 has a negative twist distribution, i.e. the angle of incidence decreases continuously from the aforementioned end part to the tip of the tip 12. The design of the negative torsion distribution can ensure that the induced speed distribution of the blade 1 is more uniform in the flying process so as to obtain better aerodynamic performance and noise reduction effect. Further, in the portion where the angle of incidence changes continuously, the slope of the angle of incidence change at the tip 12 is larger than that at the main blade 11, that is, an "accelerated negative twist" is formed at the tip 12. Further, the relative chord length (C/R) of the tip 12 gradually decreases in the spanwise direction, and the relative chord length of the tip 12 is smaller than that of the main blade 11. The optimized design of the blade tip 12 can weaken blade tip vortex and reduce the interference of the blade vortex, thereby achieving the purpose of reducing the noise of the propeller. The rate of change of the relative chord length of the tip 12 is greater than that of the main blade in the portion near the tip, in other words, the tip 12 is of a sharpened design.
A blade 1 designed according to the above design parameters, in which the blade radius R is 210 mm, is given in the following by way of example. Reference may also be made to fig. 4 to 10.
Table 1: design parameters of chord length and mounting angle of each section of blade
The plurality of blades 1 are connected at a rotation center and arranged at equal intervals in the circumferential direction with respect to the rotation center, integrally formed as a propeller 100. The plurality of blades 1 may be integrally formed, so as to ensure the overall structural strength of the propeller 100, or the propeller 100 may also be separately formed, for example, each blade 1 is mounted on the hub, and the rotation center of the blade 1 is the axis of the hub. Fig. 2 shows an embodiment of a propeller with three blades 1, which can reduce the rotational speed corresponding to the design drag, thus effectively reducing noise.
The beneficial effects of the propeller 100 of the present disclosure in improving aerodynamic efficiency and reducing noise of a rotorcraft will be further illustrated below by comparative experiments on aerodynamics of the propeller 100 of the present disclosure having three blades and the propellers provided in the prior art (two blades, large chord length, small mounting angle).
Table 2: measured noise contrast
Wherein, survey point distance refers to the distance of rotor craft apart from the noise meter. As can be seen from table 2, the rotorcraft having the propeller 100 of the present application all had lower noise than the rotorcraft having the prior art propeller design at different test distances.
Table 3: comparing time of flight with distance of flight
As can be seen from table 3, the rotorcraft with the propeller of the present application had a greater lift than the rotorcraft with the propeller of the present design, both when underway and on voyage, further verifying the effect of the propeller of the present application in improving aerodynamic performance.
Based on the theoretical analysis and experimental verification, the rotorcraft disclosed by the invention has excellent aerodynamic efficiency especially under the condition of low Reynolds number flow (10000-400000), and can consume less power under the condition of generating the same lift force or generate larger lift force under the condition of consuming the same power. Furthermore, aerodynamic noise generated by the rotor at high speed is a major source of noise in rotorcraft. Because the improvement of rotor craft aerodynamic efficiency, under the condition that same lifting surface distributes, required rotational speed is lower, therefore can the effectual noise that reduces rotor craft flight in-process and produce, promotes user experience.
A second object of the present disclosure is to provide a rotorcraft that includes any one of the propellers 100 described above, and that has all of the advantages thereof, which will not be described in detail herein.
The preferred embodiments of the present disclosure are described in detail with reference to the accompanying drawings, however, the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical idea of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.
It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. In order to avoid unnecessary repetition, various possible combinations will not be separately described in this disclosure.
In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.
Claims (10)
1. A propeller comprising a plurality of blades connected at a center of rotation, characterized in that:
the blade mount angle is 24 ° ± 1.5 ° at 35.7% of the radius of the propeller from the center of rotation;
at 59.5% of the radius of the propeller from the center of rotation, the blade has a setting angle of 16 ° ± 1.5 °;
the blade mount angle is 12 ° ± 1.5 ° at 83.3% of the radius of the propeller from the center of rotation.
2. The propeller of claim 1, wherein:
at a distance of 23.8% of the radius of the propeller from the center of rotation, the pitch angle of the blades is 21 ° ± 1.5 °;
the blade mount angle is 20 ° ± 1.5 ° at 47.6% of the radius of the propeller from the center of rotation;
at 71.4% of the radius of the propeller from the center of rotation, the blade has a setting angle of 14 ° ± 1.5 °;
the blade mount angle is 5 ° ± 1.5 ° at a distance of 95.2% of the radius of the propeller from the center of rotation.
3. The propeller of claim 1 or 2, wherein:
the relative chord length of the blade is 0.19 +/-0.02 at a distance of 35.7% of the radius of the propeller from the rotation center;
at 59.5% of the radius of the propeller from the centre of rotation, the relative chord length of the blade is 0.13 ± 0.02;
the relative chord length of the blade is 0.09 +/-0.02% at the position which is 83.3% of the radius of the propeller from the rotating center,
wherein the relative chord length of the blade is the ratio of the local chord length of the blade to the radius of the blade.
4. The propeller of claim 3, wherein:
at a distance of 23.8% of the radius of the propeller from the center of rotation, the relative chord length of the blade is 0.17 ± 0.02;
the relative chord length of the blade is 0.16 +/-0.02 at the position which is 47.6 percent of the radius of the propeller away from the rotation center;
the relative chord length of the blade is 0.11 plus or minus 0.02 at 71.4% of the radius of the propeller from the center of rotation;
the relative chord length of the blade is 0.07 + -0.02 at 95.2% of the radius of the propeller from the center of rotation.
5. The propeller of claim 1, wherein: the blade has a leading edge and a trailing edge and is formed with a main blade and a blade tip in the span-wise direction, where the leading edge and the trailing edge are swept back.
6. The propeller of claim 5 wherein the tip has a stagger angle that is less than the stagger angle of the root of the main blade, the blades have a negative twist distribution from at least the tip portion of the main blade to the tip, and the rate of change of the stagger angle at the tip is greater than the rate of change of the stagger angle at the main blade.
7. The propeller as claimed in claim 5 or 6 wherein the relative chord length of the tip tapers in the spanwise direction and is less than the relative chord length of the main blade.
8. The propeller of claim 1 wherein said blades are three of the same construction.
9. The propeller of claim 8 wherein three of said blades are integrally formed and are equally circumferentially spaced.
10. A rotorcraft, comprising at least one propeller as recited in any one of claims 1-9.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110593820.6A CN113022849B (en) | 2021-05-28 | 2021-05-28 | Propeller and rotary wing aircraft |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110593820.6A CN113022849B (en) | 2021-05-28 | 2021-05-28 | Propeller and rotary wing aircraft |
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| CN113022849A true CN113022849A (en) | 2021-06-25 |
| CN113022849B CN113022849B (en) | 2024-02-06 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114633877A (en) * | 2022-02-17 | 2022-06-17 | 惠阳航空螺旋桨有限责任公司 | Low-noise propeller |
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| EP0265335B1 (en) * | 1986-10-24 | 1990-02-07 | Office National d'Etudes et de Recherches Aérospatiales (O.N.E.R.A.) | Propellers, in particular for aircraft propulsion units |
| CN207000809U (en) * | 2017-04-07 | 2018-02-13 | 深圳市大疆创新科技有限公司 | Blade, propeller, power suit and unmanned vehicle |
| CN207466960U (en) * | 2017-11-14 | 2018-06-08 | 深圳市易飞行科技有限公司 | A kind of folding propeller and unmanned plane |
| CN208291466U (en) * | 2018-05-25 | 2018-12-28 | 深圳市大疆创新科技有限公司 | Propeller, Power Component and aircraft |
| CN109923036A (en) * | 2017-06-30 | 2019-06-21 | 深圳市大疆创新科技有限公司 | Propeller, Power Component and aircraft |
| CN210479019U (en) * | 2019-08-08 | 2020-05-08 | 深圳市帅泰科技有限公司 | Blade, propeller and aircraft |
-
2021
- 2021-05-28 CN CN202110593820.6A patent/CN113022849B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0265335B1 (en) * | 1986-10-24 | 1990-02-07 | Office National d'Etudes et de Recherches Aérospatiales (O.N.E.R.A.) | Propellers, in particular for aircraft propulsion units |
| CN207000809U (en) * | 2017-04-07 | 2018-02-13 | 深圳市大疆创新科技有限公司 | Blade, propeller, power suit and unmanned vehicle |
| CN109923036A (en) * | 2017-06-30 | 2019-06-21 | 深圳市大疆创新科技有限公司 | Propeller, Power Component and aircraft |
| CN207466960U (en) * | 2017-11-14 | 2018-06-08 | 深圳市易飞行科技有限公司 | A kind of folding propeller and unmanned plane |
| CN208291466U (en) * | 2018-05-25 | 2018-12-28 | 深圳市大疆创新科技有限公司 | Propeller, Power Component and aircraft |
| CN210479019U (en) * | 2019-08-08 | 2020-05-08 | 深圳市帅泰科技有限公司 | Blade, propeller and aircraft |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114633877A (en) * | 2022-02-17 | 2022-06-17 | 惠阳航空螺旋桨有限责任公司 | Low-noise propeller |
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