CN112918668B - Rotor of rotor craft and rotor craft - Google Patents
Rotor of rotor craft and rotor craft Download PDFInfo
- Publication number
- CN112918668B CN112918668B CN201911244213.8A CN201911244213A CN112918668B CN 112918668 B CN112918668 B CN 112918668B CN 201911244213 A CN201911244213 A CN 201911244213A CN 112918668 B CN112918668 B CN 112918668B
- Authority
- CN
- China
- Prior art keywords
- airfoil
- rotor
- blade
- wing
- line
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C27/00—Rotorcraft; Rotors peculiar thereto
- B64C27/32—Rotors
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C27/00—Rotorcraft; Rotors peculiar thereto
- B64C27/32—Rotors
- B64C27/46—Blades
- B64C27/467—Aerodynamic features
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C27/00—Rotorcraft; Rotors peculiar thereto
- B64C27/32—Rotors
- B64C27/46—Blades
- B64C27/473—Constructional features
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C3/00—Wings
- B64C3/10—Shape of wings
Abstract
The present disclosure relates to a rotor of a rotorcraft and a rotorcraft, wherein the rotor of the rotorcraft comprises a blade and a hub, the blade is mounted on a drive assembly of the rotorcraft through the hub, an airfoil of the blade is composed of a leading edge, a trailing edge, and an up-camber line and a down-camber line between the leading edge and the trailing edge, a ratio of a maximum thickness a of the airfoil of the blade to a chord length c of the airfoil is a/c =6.85%, and the maximum thickness is located at x/c = 30.5%; the ratio of the maximum camber b of the airfoil of the blade to the chord length c of the airfoil is b/c =6.6%, the maximum camber b being located at x/c = 47.1%. The rotor that obtains through above-mentioned technical scheme has higher aerodynamic efficiency, lighter weight, and under the same lifting surface distribution design, required rotational speed is lower, and the noise is littleer.
Description
Technical Field
The utility model relates to an aircraft technical field specifically relates to a rotor and rotor craft of rotor craft.
Background
Improving aerodynamic efficiency is an important task in aircraft 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 airfoil profile of a rotorcraft plays an important role in improving aerodynamic efficiency. Existing rotors are designed primarily around large manned aircraft, which are typically in high reynolds number (typically over 1000,000) flows. Less rotor research is currently being conducted for many low reynolds number (500,000 or less) flows, such as logistics distribution, plant protection, aerial photography, etc. The existing rotor wing generally has the problems of low lift coefficient, low lift-drag ratio and the like under the low Reynolds number flow, so that the aerodynamic efficiency of the rotor wing unmanned aerial vehicle is low.
Disclosure of Invention
It is a first object of the present disclosure to provide a rotor for a rotary-wing aircraft that has a higher lift coefficient and a greater lift-to-drag ratio in a low reynolds number environment, improving the aerodynamic efficiency of the rotary-wing aircraft.
In order to achieve the above object, the present disclosure provides a rotor of a rotorcraft, comprising a blade and a hub, the blade being mounted to a drive assembly of the rotorcraft via the hub, an airfoil of the blade being formed by a leading edge, a trailing edge, and an up-camber line and a down-camber line therebetween, a ratio of a maximum thickness a of the airfoil of the blade to a chord length c of the airfoil being a/c =6.85%, the maximum thickness being located at x/c = 30.5%; the ratio of the maximum camber b of the airfoil of the blade to the chord length c of the airfoil is b/c =6.6%, the maximum camber b being located at x/c = 47.1%; where x is the distance along the chord line from the leading edge to the trailing edge, the values of a/c, b/c, x/c, respectively, having a maximum error of + -3%.
A second object of the present disclosure is to provide a rotorcraft having a rotor of the rotorcraft described above.
Through above-mentioned technical scheme, the rotor of the rotor craft that this disclosure provided has higher maximum lift coefficient and higher lift-drag ratio under low reynolds number flows to can improve rotor craft's aerodynamic efficiency, because rotor craft's aerodynamic efficiency's improvement in addition, under the condition that same lifting surface distributes, required rotational speed is lower, can 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, but do not constitute a limitation of the disclosure. In the drawings:
FIG. 1 is a schematic view of an airfoil profile of a rotor shown in accordance with an exemplary embodiment;
FIG. 2 is an airfoil of the present disclosure and VR7 airfoil at low Reynolds number Re =1.3 × 10 4 Comparing the curves of the time maximum lift coefficient;
FIG. 3 is an airfoil of the present disclosure and VR7 airfoil at low Reynolds number Re =2.7 × 10 4 Comparing the curves of the time maximum lift coefficient;
FIG. 4 is an airfoil of the present disclosure and VR7 airfoil at low Reynolds number Re =4 × 10 4 Comparing the curves of the time maximum lift coefficient;
fig. 5 is an airfoil of the present disclosure and VR7 airfoil at low reynolds number Re =1.8 × 10 5 Comparing the curves of the time maximum lift coefficient;
FIG. 6 is an airfoil of the present disclosure and VR7 airfoil at low Reynolds number Re =4 × 10 5 Comparing the curves of the time maximum lift coefficient;
FIG. 7 is an airfoil of the present disclosure and VR7 airfoil at low Reynolds number Re =1.3 × 10 4 A time maximum lift-drag ratio curve comparison graph;
fig. 8 is an airfoil of the present disclosure and VR7 airfoil at low reynolds number Re =2.7 × 10 4 A time maximum lift-drag ratio curve comparison graph;
FIG. 9 is an airfoil of the present disclosure and VR7 airfoil at low Reynolds number Re =4 × 10 4 A time maximum lift-drag ratio curve comparison graph;
fig. 10 is an airfoil of the present disclosure and VR7 airfoil at low reynolds number Re =1.8 × 10 5 A time maximum lift-drag ratio curve comparison graph;
FIG. 11 is an airfoil of the present disclosure and VR7 airfoil at low Reynolds number Re =4 × 10 5 A time maximum lift-drag ratio curve comparison graph;
figure 12 is a perspective view of a rotor shown in accordance with an exemplary embodiment;
figure 13 is a plan view of a rotor shown in accordance with an exemplary embodiment;
FIG. 14 is a force effect comparison graph of a blade of the present disclosure to a T-motor pure carbon blade.
Description of the reference numerals
1. The leading edge 12 and the trailing edge of the blade 11
13. Upper arc 14 and lower arc 15 chord
16. Heel 171 of blade root 17
18. Maximum thickness of lower airfoil a of upper airfoil 19
b maximum camber c chord length
Detailed Description
The following detailed description of the embodiments of the disclosure refers to 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 rotor of the rotorcraft and the rotorcraft of the present disclosure will be 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.
As shown in fig. 12 and 13, the present disclosure provides a rotor of a rotorcraft, the rotor comprising a blade 1 and a hub, the blade 1 being mounted to a drive assembly of the rotorcraft via the hub. The drive assembly may be, for example, a rotary electric machine mounted on the fuselage of the rotorcraft, the output shaft of which is connected to the hub to rotate the blades 1. The aircraft body of the rotor aircraft can be provided with a plurality of rotors, and the flight attitude of the rotor aircraft can be changed by adjusting the rotating speed and the attitude of the rotors so as to switch between actions of hovering, traveling or heeling.
The blade 1 of the present disclosure may be made of any material in the related art, including but not limited to metal materials, plastics, carbon fibers, and the like. In addition, molding may be employed in the manufacture. Stamping, forging and other processing means in various related technologies.
As shown in fig. 1, the airfoil of the blade 1 of the present disclosure is composed of a leading edge 11, a trailing edge 12, and an up camber line 13 and a down camber line 14 between the leading edge 11 and the trailing edge 12. The ratio of the maximum thickness a of the airfoil of the blade 1 to the chord length c of the airfoil is a/c =6.85%, the maximum thickness being located at x/c = 30.5%; the ratio of the maximum camber b of the airfoil of the blade to the chord length c of the airfoil is b/c =6.6%, the maximum camber b being located at x/c = 47.1%; where x is the distance from the leading edge 11 to the trailing edge 12 along the chord line 15, a/c, b/c, x/c each have a maximum error of + -3%, i.e., the profile of the airfoil made up of a/c, b/c, x/c within the tolerance of + -3% falls within the scope of the present disclosure as claimed.
Compared with the airfoil design of the existing rotor wing, the airfoil design has the advantage that the flowing characteristic of low Reynolds number is considered, the maximum thickness a is pushed to the tail edge 12 when the airfoil design is carried out, and therefore the phenomenon that the airflow is separated in the upper camber line 13 of the rotor wing too early and the lift loss is caused is avoided. In addition, through the improvement on the maximum thickness a and the maximum curvature b, the boundary layer of the front section of the wing profile is more stable, the separation point is delayed, and the working of the cambered surface on the front section of the wing profile is facilitated.
Based on the technical scheme and theoretical analysis, the rotor of the rotorcraft disclosed by the invention has a higher maximum lift coefficient and a higher lift-drag ratio under the condition of low Reynolds number flow, shows excellent aerodynamic efficiency, 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.
According to one embodiment of the present disclosure, as shown in FIG. 1, the camber line 13 may be represented by a camber line coordinate value pair x/c, y u The camber line 14 may be defined by a camber line coordinate value pair x/c, y l Defined by/c, the pairs of values of the upper arc coordinates x/c, y u C and said pair of lower arc coordinate values x/c, y l The/c may be defined according to:
TABLE 1 airfoil top and bottom surface characteristic point coordinates
Wherein, y u Is the distance of the upper camber line 13 perpendicular to the chord line 15, y l Is the distance that the camber line 14 is perpendicular to the chord line 15.
Numerical value pairs of arc ascending coordinates x/c, y in this disclosure u C and lower arc coordinate value pairs x/c, y l The maximum error of each of/C is equal to + -3%, i.e., the upper arc coordinate pair X/C, Y within the tolerance of + -3% error u Numerical value pairs of/C and lower arc line coordinates X/C, Y l The profile of the airfoil surrounded by the/C falls within the protection range claimed by the disclosure, and the obtained airfoil can still achieve the beneficial effects of the airfoil within the error range. In addition, the coordinate pairs adopted when the airfoil profile is defined by the present disclosure are dimensionless coordinate values, and the shape of the airfoil is not changed when the data in the table 1 is proportionally enlarged or reduced.
The beneficial effects of the rotor of the present disclosure in improving aerodynamic efficiency of a rotorcraft will be further illustrated below by aerodynamic comparison experiments with the rotor of the present disclosure (E376) and the rotor of boeing (VR 7) developed specifically for a vertical take-off and landing craft under low reynolds number flow.
As shown in the following Table 2, reynolds numbers Re of 1.3X 10 were selected respectively 4 、2.7×10 4 、4×10 4 、1.8×10 5 And 4X 10 5 When the attack angle is in the range of-5-15 degrees, the maximum lift coefficient of the E376 airfoil profile and the Boeing VR7 airfoil profile is compared. The maximum lift coefficients of the airfoils of the present disclosure are each greater than the maximum lift coefficient of VR7 airfoils within a selected range of reynolds numbers, specifically, when Re =1.3 × 10 4 In time, the maximum lift coefficient of the E376 airfoil of the disclosure is improved by 58.23% compared with that of the VR7 airfoil; when Re =2.7 × 10 4 In time, the maximum lift coefficient of the E376 airfoil of the disclosure is increased by 39.81% compared with that of the VR7 airfoil; when Re =4 × 10 4 In time, the maximum lift coefficient of the E376 airfoil of the disclosure is improved by 32.74% compared with that of the VR7 airfoil; when Re =1.8 × 10 5 In time, the maximum lift coefficient of the E376 airfoil of the disclosure is improved by 17.27% compared with that of the VR7 airfoil; when Re =4 × 10 5 In time, the maximum lift coefficient of the E376 airfoil of the disclosure is improved by 19.31% compared with that of the VR7 airfoil. That is, the maximum lift coefficient of the E376 airfoil of the present disclosure can be increased by at least 17% as compared to the VR7 airfoil. Referring also to fig. 2-6, the lift coefficient of the E376 airfoil of the present disclosure is generally higher than that of the VR7 airfoil with variation in angle of attack over the effective operating point range of the airfoil at low reynolds numbers.
TABLE 2 maximum lift coefficient at different Reynolds numbers
| Re | CLmax_VR7 | Clmax_E376 | Lifting of |
| 13000 | 0.79 | 1.25 | 58.23％ |
| 27000 | 1.03 | 1.44 | 39.81％ |
| 40000 | 1.13 | 1.5 | 32.74％ |
| 180000 | 1.39 | 1.63 | 17.27％ |
| 400000 | 1.45 | 1.73 | 19.31％ |
As shown in the following Table 3, reynolds numbers Re of 1.3X 10 were selected respectively 4 、2.7×10 4 、4×10 4 、1.8×10 5 And 4X 10 5 When the attack angle is in the range of-5-15 degrees, the maximum lift-drag ratio of the E376 airfoil and the Boeing VR7 airfoil is compared. The maximum lift-to-drag ratios of the airfoils of the present disclosure are all greater than the maximum lift-to-drag ratio of VR7 airfoils over the range of reynolds numbers chosen, specifically, when Re =1.3 × 10 4 In time, the maximum lift-drag of the E376 airfoil of the disclosure is improved by 53.39% compared with that of the VR7 airfoil; when Re =2.7 × 10 4 In time, the maximum lift-drag of the E376 airfoil of the disclosure is improved by 41.31% compared with that of the VR7 airfoil; when Re =4 × 10 4 In time, the maximum lift-drag comparison VR7 profile lift of the E376 profile of the present disclosure37.48 percent; when Re =1.8 × 10 5 In time, the maximum lift-drag of the E376 airfoil of the disclosure is improved by 28.66% compared with that of the VR7 airfoil; when Re =4 × 10 5 In time, the maximum lift-drag of the E376 airfoil of the disclosure is improved by 21.27% compared with that of the VR7 airfoil. That is, the maximum lift-drag ratio of the E376 airfoil profile can be increased by at least 21% compared with the VR7 airfoil profile. Referring also to fig. 7-11, the lift-to-drag ratio of the E376 airfoil of the present disclosure is generally higher than that of the VR7 airfoil with a change in angle of attack over the effective operating range of the airfoil at low reynolds numbers.
TABLE 3 maximum lift coefficient at different Reynolds numbers
| Re | CL/CDmax_VR7 | CL/CDmax_E376 | Lifting of |
| 13000 | 11.5 | 17.64 | 53.39％ |
| 27000 | 20.55 | 29.04 | 41.31％ |
| 40000 | 26.2 | 36.02 | 37.48％ |
| 180000 | 42.25 | 54.36 | 28.66％ |
| 400000 | 50.72 | 61.51 | 21.27％ |
Through above-mentioned contrast experiment, this disclosure E376 airfoil and VR7 airfoil are under low reynolds number, and maximum lift coefficient and maximum lift-drag ratio all have apparent promotion, prove that the rotor that adopts this disclosure's airfoil has higher aerodynamic efficiency, lighter weight. In addition, because the improvement of rotor craft aerodynamic efficiency, under the condition that same lifting surface distributes, required rotational speed is lower, consequently can effectually reduce the noise that rotor craft flight in-process produced, especially logistics distribution etc. are applied to the comparatively dense region of population, and reduction that can the at utmost is to the interference of resident's life around, promotes user's experience.
According to one embodiment of the present disclosure, as shown in fig. 12 and 13, the blade 1 of the present disclosure includes a blade root 16, a blade tip 17, and an upper wing surface 18 and a lower wing surface 19 which are disposed opposite to each other, one side of the upper wing surface 18 and one side of the lower wing surface 19 are connected to form a leading edge 11, the other side is connected to form a trailing edge 12, and a portion of the blade 1 extending from a position with a radius of 35% to the blade tip 17 has the airfoil shape.
The portion of the disclosed blade 1 extending from 35% of the radius to the tip 17 has the airfoil shape described above in the present disclosure, and thus the disclosed blade 1 has all the benefits of the airfoil shape described above. The reason that the airfoil described above is not used for all sections of the blade 1 of the present disclosure is because the root 16 is used for connection with the hub, thereby enabling the hub to rotate under the drive of the drive assembly. The root 16 is closer to the hub than the main part of the blade 1 and the tip 17 part and will therefore be subjected to a higher output torque. For structural reinforcement purposes, the blade 1 of the present disclosure may employ a thickening process before 35% of its radius. In addition, the linear speed of rotation at a portion of the blade 1 of the present disclosure before 35% of its radius is low, and thus contributes little to the lift, so that even if this portion of the airfoil takes a shape different from that of the airfoil of the present disclosure, it does not have a substantial effect on the force efficiency and aerodynamic efficiency. It should be understood that the blade 1 of the present disclosure does not present all technical obstacles to the overall construction of the blade that employ the airfoil of the present disclosure.
This disclosed rotor is at every section homoenergetic along the span of paddle 1 and is in the best working segment to reduce the resistance of air, improve pulling force and efficiency, thereby can increase rotor craft's time of endurance, can also reduce the noise that the aircraft produced in flight in addition, promote user experience.
The upper airfoil 18 is defined by an upper airfoil characteristic line constituted by (kx, ky, kz) defined by a plurality of coordinate pairs, the lower airfoil 19 is defined by a lower airfoil characteristic line constituted by (kx, ky, kz) defined by a plurality of coordinate pairs, the upper and lower airfoil characteristic lines being defined according to the following:
TABLE 4a coordinates of feature points of the airfoil feature lines
TABLE 4b characteristic point coordinates of lower airfoil surface characteristic line
Wherein, the x direction is the spanwise direction of rotor, and the y direction is the chord length direction of rotor, and z is the thickness direction. k = a/229, wherein a is the value of the radius of the rotor. Table 4 presents stereo profile data for an embodiment of a selected pitch radius of 229 mm, it being understood that clusters of curves scaled up or down using this data, with smooth transitions between the characteristic lines, are also within the scope of the practice of the present disclosure.
The following is an example of how to map out a blade having the same profile as the present disclosure, with other radius sizes being selected. When the radius dimension of the blade is 600 mm, i.e. a =600, k =2.62009, and then k is multiplied by the corresponding coordinate values in table 4 respectively, and finally a new set of feature point coordinates of the feature line is obtained, for example, the corresponding coordinates in the upper airfoil feature line 5 in table 4a become (297.60030, -31.16505, 7.31181), (297.60030, -30.85444, 7.64422) \ 8230; the corresponding coordinates in the lower airfoil feature line 5 in Table 4b become (297.60030, -31.16505, 7.31181), (297.60030, -31.01191, 6.97195) \8230; (8230;).
The maximum error of each of the upper and lower airfoil characteristic lines is equal to ± 3%, that is, the shape of the airfoil formed by the upper and lower airfoil characteristic lines within the tolerance of ± 3% error falls within the scope of protection claimed by the present disclosure.
According to the data in the above table, it can be seen that the blade 1 of the present disclosure has a three-dimensional structure defined by the above three characteristic lines in a distant interval from the center (approximately x interval of 113 to 196), and the corresponding blade structure in this interval is a main structure in the blade and is a relatively important tension generation area, and by optimizing the value of the characteristic line in this area, the main part of the blade 1 can be in a better working section in the span-wise direction, so as to reduce the resistance of air, improve the tension and efficiency, and increase the endurance time of the rotorcraft, and in addition, the noise generated by the rotorcraft during flight can be reduced, and the user experience can be improved.
In the present disclosure, the upper airfoil surface feature line and the lower airfoil surface feature line are further defined according to:
TABLE 5a coordinates of feature points of airfoil feature lines
TABLE 5b characteristic point coordinates of lower airfoil surface characteristic line
The choice of a zone closer to the centre (zone approximately 27-69) continues to be optimised because the root 16 is intended to be connected to the hub so that the blades can be rotated by the drive assembly. The root 16 is now located closer to the hub than the main part of the blade 1 and the tip 17 part and will therefore be subjected to a higher torque. The present disclosure provides for thickening at the root 16 portion, i.e., a bulge is formed outward along the chord of the root 16 to increase the structural strength of the root 16 portion.
In the present disclosure, the upper airfoil surface feature line and the lower airfoil surface feature line are further defined according to:
table 6a coordinates of feature points of airfoil feature lines
Table 6b coordinates of feature points of airfoil feature lines
Thus, the present disclosure further refines the main body portion of the blade 1, so that the transition of the main body portion of the blade 1 is smoother, and no sharp twisting occurs. The smooth transition structure can further improve the overall structural strength of the paddle 1, is not easy to break, improves the reliability of the main body part of the paddle 1 in work, and has higher tension and efficiency.
In the present disclosure, the upper airfoil surface feature line and the lower airfoil surface feature line are further defined according to: TABLE 7a coordinates of feature points for the airfoil feature lines
TABLE 7b characteristic point coordinates of lower airfoil surface characteristic line
The present disclosure also further refines the area of the blade root 16 closer, and improves the smoothness at the blade root 16 to improve the structural strength of the blade 1.
Further, for promoting the effect of making an uproar that falls, this disclosed rotor is along every section homoenergetic in the span direction of paddle 1 and is in the best working segment to reduce the resistance of air, improve pulling force and efficiency, thereby can increase rotor craft's time of endurance, can also reduce the noise that the aircraft produced when flight in addition, promote user's use and experience.
According to an embodiment of the present disclosure, as shown in fig. 12 and 13, a swept portion 171 is further formed at the wing tip 17, the swept portion 171 extends from the leading edge 11 to the trailing edge 12 in a bending manner, and an upper wing surface characteristic line and a lower wing surface characteristic line of the swept portion 171 are defined according to the following:
TABLE 8a coordinates of feature points of airfoil feature lines
TABLE 8b characteristic point coordinates of lower airfoil surface characteristic lines
Wherein, the x direction is the span direction of rotor, and the y direction is the chord length direction of rotor, and z is the thickness direction. k = a/229, wherein a is the value of the radius of the rotor. Table 8 is a three-dimensional profile data for an embodiment of a selected pitch radius of 229 mm, it being understood that clusters of curves scaled up or down using this data, with smooth transitions between the characteristic lines, are also within the scope of the practice of the present disclosure.
The following is an exemplary way to provide how to obtain a sweep 171 having the same profile as the present disclosure, with other selected radius blade sizes. For example, if the radius dimension of the blade is 600 mm, i.e., a =600, k =2.62009, then k is multiplied by the corresponding coordinate values in table 8, respectively, to obtain the feature point coordinates of a new set of feature lines, for example, the corresponding coordinates in the upper airfoil feature line 10 in table 8a become (549.60056, -22.77924, 2.38606), (549.60056, -22.77924, 2.58626) \ 8230; \8230; the corresponding coordinates in the lower airfoil feature line 10 in Table 8b become (549.60056, -22.77924, 2.38606), (549.60056, -22.67366, 2.21162) \8230;.
The maximum error of each of the upper and lower airfoil characteristic lines is equal to ± 3%, i.e., the shape of the airfoil formed by the upper and lower airfoil characteristic lines within the tolerance of ± 3% error falls within the scope of the present disclosure.
In the present disclosure, by designing the three-dimensional structure formed by the two airfoil characteristic lines, the swept-back portion 171 is configured, and the presence of the swept-back portion 171 can cut off the air flow in the direction of the blade 1 when the blade 1 rotates, thereby reducing the vortex formed by the blade tip 17 portion and reducing the strength of the vortex formed by the blade tip 17 portion, and in addition, the swept-back portion 171 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 a certain thickness, and finally reduce the rotation noise generated when the blade 1 rotates.
In order to make the sweepback more effective, the present disclosure adds a wing surface characteristic line to define the sweepback. Specifically, as shown in table 9 below:
table 9a coordinates of feature points of airfoil feature lines
TABLE 9b characteristic point coordinates of lower airfoil surface characteristic line
By further limiting the characteristic lines of the upper and lower airfoils of the swept portion 171, the swept portion 171 is smoother, the vortex formed at the blade tip 17 is more stable, and the noise reduction effect can be further improved.
The beneficial effects of the blade 1 of the present disclosure in improving the aerodynamic efficiency of a rotorcraft will be further illustrated by force versus effect testing of the blade of the present disclosure (18 inch bakelite) and a T-motor pure carbon blade.
As shown in fig. 14, the force efficiency of a rotorcraft using the blades 1 of the present disclosure is improved by 4.9% on average compared to a T-motor pure carbon blade. Specifically, under 1.5kg of tension, the force effect is improved by 2.7%; under the tension of 1.1kg, the force effect is improved by 5 percent; the pull force is improved by 7 percent under the tension of 1.8 kg. In addition, through experiments and numerical simulation, compared with a T-motor pure carbon blade, the noise of the blade 1 is reduced by 3 decibels. According to the method, numerical simulation and wind tunnel test are adopted in the test of the force effect, and the accuracy of the test result is guaranteed.
According to one embodiment of the present disclosure, as shown in fig. 13, there may be at least two blades 1, and at least two blades 1 are connected together by a root 16 and are centrosymmetric with respect to a center point position of the connection. At least two paddle 1 can integrated into one piece to can guarantee paddle 1's holistic structural strength, perhaps paddle 1 also can adopt the fashioned design of components of a whole that can function independently, for example install each paddle 1 respectively on the propeller hub, make the installation and the change of paddle 1 comparatively convenient, the axis that the center of rotation of paddle 1 was the propeller hub place this moment.
A second object of the present disclosure is to provide a rotorcraft comprising a rotor of the rotorcraft described above. This rotor craft has all beneficial effects of the rotor of above-mentioned rotor craft, and this disclosure is not repeated 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. To avoid unnecessary repetition, the disclosure does not separately describe various possible combinations.
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 gist of the present disclosure.
Claims (9)
1. A rotor for a rotary-wing aircraft, comprising at least two blades (1) and a hub, the blades (1) being mounted on a drive assembly of the rotary-wing aircraft by means of the hub, the airfoil of the blade (1) being constituted by a leading edge (11), a trailing edge (12), and an upper camber line (13) and a lower camber line (14) which are located between the leading edge (11) and the trailing edge (12), the airfoil of the blade (1) having a ratio of a maximum thickness a to a chord length c of the airfoil of a/c =6.85%, the maximum thickness being located at x/c = 30.5%; the ratio of the maximum camber b of the airfoil of the blade (1) to the chord length c of the airfoil is b/c =6.6%, said maximum camber b being located at x/c = 47.1%; wherein x is the distance from the leading edge (11) to the trailing edge (12) along the chord line (15), the values of a/c, b/c, x/c respectively having a maximum error of ± 3%; the upper arc line (13) is formed by an upper arc line coordinate value pair x/c, y u C, said camber line (14) being defined by a pair of camber line coordinate values x/c, y l C, said pair of values of the upper arc coordinates x/c, y u C and said pair of lower arc coordinate values x/c, y l The/c is defined according to:
wherein, y u Is the distance of said camber line (13) perpendicular to said chord line (15), y l Is the distance of said camber line (14) perpendicular to said chord line (15), said camber line coordinate value pair x/c, y u C and said pair of lower arc coordinate values x/c, y l The maximum error of each of/c is equal to ± 3%; the paddle (1) comprises a paddle root (16), a paddle tip (17), an upper wing surface (18) and a lower wing surface (19) which are arranged oppositely up and down, one side of the upper wing surface (18) and one side of the lower wing surface (19) are connected to form the leading edge (11), the other side of the upper wing surface and the other side of the lower wing surface are connected to form the trailing edge (12), and the paddle (1) extends from 35% of the radius to the paddle tip (17)Has said airfoil profile.
2. A rotor of a rotary-wing aircraft according to claim 1, wherein the upper airfoil surface (18) is defined by an upper airfoil surface characteristic line (kx, ky, kz) defined by a plurality of coordinate pairs, the lower airfoil surface (19) is defined by a lower airfoil surface characteristic line (kx, ky, kz) defined by a plurality of coordinate pairs, the upper and lower airfoil surface characteristic lines being defined according to:
wherein, the x direction is the unfolding direction of the rotor wing, the y direction is the chord length direction of the rotor wing, and the z direction is the thickness direction; k = a/229, wherein a is the radius of the rotor; the maximum error of each of the upper airfoil profile and the lower airfoil profile is equal to ± 3%.
3. A rotor of a rotary-wing aircraft according to claim 2, wherein the upper and lower wing characteristic lines are further defined according to:
4. a rotor of a rotary-wing aircraft according to claim 3, wherein the upper and lower wing characteristic lines are further defined according to:
5. a rotor of a rotary-wing aircraft according to claim 4, wherein the upper and lower wing characteristic lines are further defined according to:
6. a rotor of a rotorcraft according to any one of claims 2 to 5, wherein a sweep (171) is formed at the tip (17), the sweep (171) extending from the leading edge (11) towards the trailing edge (12), the upper and lower profile lines of the sweep (171) being defined according to:
7. a rotor of a rotorcraft according to claim 6, wherein the upper and lower profile lines of the swept back portion (171) are further defined according to:
8. a rotor of a rotorcraft according to claim 1, wherein at least two of the blades (1) are integrally or separately formed.
9. A rotorcraft, comprising a rotor of a rotorcraft according to any one of claims 1-8.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911244213.8A CN112918668B (en) | 2019-12-06 | 2019-12-06 | Rotor of rotor craft and rotor craft |
| PCT/CN2020/088363 WO2021109441A1 (en) | 2019-12-06 | 2020-04-30 | Rotor wing of rotorcraft and rotorcraft |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911244213.8A CN112918668B (en) | 2019-12-06 | 2019-12-06 | Rotor of rotor craft and rotor craft |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112918668A CN112918668A (en) | 2021-06-08 |
| CN112918668B true CN112918668B (en) | 2022-12-20 |
Family
ID=76161869
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911244213.8A Active CN112918668B (en) | 2019-12-06 | 2019-12-06 | Rotor of rotor craft and rotor craft |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN112918668B (en) |
| WO (1) | WO2021109441A1 (en) |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9688395B2 (en) * | 2013-12-04 | 2017-06-27 | Sikorsky Aircraft Corporation | Boundary layer ingesting blade |
| CN104354850B (en) * | 2014-10-30 | 2016-03-09 | 中国人民解放军空军航空大学 | A kind of HAE fixed wing aircraft Airfoil |
| CN105752314B (en) * | 2016-03-22 | 2017-03-29 | 西北工业大学 | A kind of high-altitude low speed Natural Laminar Flow high-lift airfoil |
| CN206202665U (en) * | 2016-11-09 | 2017-05-31 | 亿航智能设备（广州）有限公司 | Propeller, Power Component and aircraft |
| CN107444611B (en) * | 2017-08-01 | 2020-04-21 | 中国航空工业集团公司西安飞机设计研究所 | General high-lift aircraft wing section |
| CN107757871B (en) * | 2017-09-20 | 2023-11-28 | 中国水利水电科学研究院 | Airfoil profile for light and small fixed wing unmanned aerial vehicle |
| CN208149614U (en) * | 2018-04-25 | 2018-11-27 | 深圳市大疆创新科技有限公司 | Propeller, Power Component and aircraft |
| CN211364914U (en) * | 2019-12-06 | 2020-08-28 | 北京二郎神科技有限公司 | Rotor craft's paddle and rotor craft |
-
2019
- 2019-12-06 CN CN201911244213.8A patent/CN112918668B/en active Active
-
2020
- 2020-04-30 WO PCT/CN2020/088363 patent/WO2021109441A1/en active Application Filing
Also Published As
| Publication number | Publication date |
|---|---|
| CN112918668A (en) | 2021-06-08 |
| WO2021109441A1 (en) | 2021-06-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR102471407B1 (en) | VTOL aircraft using rotors to simulate the dynamics of a rigid wing | |
| US8066219B2 (en) | Anhedral tip blades for tiltrotor aircraft | |
| JP5078883B2 (en) | Rotor blade of high speed rotorcraft | |
| CN211364914U (en) | Rotor craft's paddle and rotor craft | |
| CN205366054U (en) | Screw, power component and aircraft | |
| JP3802209B2 (en) | Wing with swept tip for aircraft rotor | |
| CN110155319B (en) | Method for modifying a blade to increase its negative stall angle of attack | |
| CN207826548U (en) | A kind of high-efficient low-noise rotor | |
| CN108163192A (en) | A kind of high-efficient low-noise rotor | |
| CN109110124A (en) | A kind of new Main Rotor Blade | |
| CN110896624A (en) | Screw, power component and aircraft | |
| EP0262071A1 (en) | Helicopter blade airfoil | |
| CN211364941U (en) | Rotor craft's paddle and rotor craft | |
| CN110155318B (en) | Method for determining the initial leading edge circle of the airfoil of a blade and method for modifying a blade to increase its negative stall angle of attack | |
| CN112918668B (en) | Rotor of rotor craft and rotor craft | |
| CN204507266U (en) | Low induced drag lifting airscrew anti-under a kind of wing tip sweepback | |
| CN109533314A (en) | A kind of light-duty unmanned helicopter Rotor Aerodynamics Shape | |
| AU2016365585B2 (en) | Autogyro rotor blade for generating lift by autorotation | |
| CN112977816B (en) | Rotor craft's paddle and rotor craft | |
| CN112918669B (en) | Rotor of rotor craft and rotor craft | |
| US10899440B2 (en) | Rotor blade tip design for improved hover and cruise performance | |
| WO2021109479A1 (en) | Blade and rotor for rotorcraft, and rotorcraft | |
| CN112298549A (en) | Tilt rotor with bionic wavy leading edge and tilt rotor aircraft | |
| CN112977815B (en) | Rotor craft, blade of rotor craft and wing section of blade | |
| CN209795824U (en) | Rotor wing section of micro-miniature rotor unmanned aerial vehicle |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |