A kind of high-efficient low-noise rotor
Technical field
The invention belongs to unmanned air vehicle technique fields, and in particular to a kind of high-efficient low-noise rotor.
Background technology
Rotor is the important component of helicopter.During helicopter flight, rotor, which rises, generates lift and the dual work of pulling force
With.Moreover, rotor also acts as the effect similar to aircraft aileron, elevator.As social economy constantly develops, nobody
Machine field has also derived numerous technical products, existing to apply the rotor in unmanned plane field mostly using oval blade, and
Using the symmetrical airfoil of condition of equivalent thickness, but its manufacture is of high cost, and manufacturing process is complicated, and symmetrical airfoil lift resistance ratio is small, and there are winged
The problem of line efficiency is low, and noise is high.
A kind of low noise blade (application number for rotor craft of Chinese patent:CN201610405088.4), it is related to
Aeromechanics technology field can improve pneumatic efficiency and drop while blade production cost and structural strength is ensured
Low noise.The present invention includes:Anti- section under smooth extended segment, sweepforward section, sweepback section and sweepback, sweepforward section, sweepback section and sweepback
Anti- section is located on the outside of blade down, and first sweepforward sweepback again is presented in blade outboard structure;Smooth extended segment is smooth outward from starting point
Specified radius part connection sweepforward section is extended to, starting point is blade and propeller hub junction;Sweepforward section connects smooth extended segment, sweepback
Section connection sweepforward section, anti-section connection sweepback section under sweepback.The program by the blade that multistage forms by realizing rotor craft
The flight of low noise, but its blade is made up of anti-section under smooth extended segment, sweepforward section, sweepback section and sweepback, planform compared with
For complexity, manufacture difficulty is big, cost is uncontrollable, and the design of multistage be easy to cause the missing of blade overall construction intensity, needs
It makes improvements.
Therefore urgent need will one kind be simple in structure, easy to process, lift resistance ratio is high, strong antijamming capability, overall structure stability
Strong high-efficient low-noise rotor.
Invention content
The object of the present invention is to provide a kind of high-efficient low-noise rotors, complex to solve prior art construction shape, system
Make the problem of difficulty is big, cost is uncontrollable, structural stability is inadequate.
The present invention provides following technical solutions:
A kind of high-efficient low-noise rotor, including blade, the blade includes rotational positioning hole, and the rotational positioning hole connects successively
It is connected to integrally formed smooth section and sweepback section;The sweepback section includes lower anti-blade tip, and the sweepback section further includes arc in sweepback
With arc under sweepback, the intersection of arc forms taper end under arc and the sweepback in the sweepback.
Preferably, the smooth section includes upper cambered surface and lower camber side, and the bending degree of the upper cambered surface is more than the lower arc
The bending degree in face can obtain higher lift resistance ratio, and this kind of blade is biconvex profile, simple in structure, easy to process.
Preferably, the blade is included with reference to chord length, and the thickness of the blade meets:Maximum blade thickness/chord length≤
8%, be conducive to ensure smaller resistance.
Preferably, the angle of sweep of the sweepback section is 22 degree, it is possible to reduce profile drag power improves lift distribution and decrease
Paddle-vortex interaction.
Preferably, the inverted diherdral of the lower anti-blade tip is 33 degree, and the design of lower anti-blade tip not only makes the induced velocity of blade
Reduce, and more uniform compared with the induced velocity distribution of ordinary rectangular blade.
Preferably, the blade includes leading edge and rear, and the leading edge can be reduced wave resistance, be made generation attached using sharp leading edge
The oblique shock wave of body is with instead of in vitro normal shock wave.
Preferably, the blade includes the string of a musical instrument, and the blade forms torsion angle, the torsion along the string of a musical instrument just torsion
Angle is no more than 15 degree, is conducive to change and extends effective angle of attack to each section, and then adjusts the exhibition of aerodynamic loading to distribution, thus
Reduce wing induced drag, improve airfoil lift.
The beneficial effects of the invention are as follows:
1st, using the blade including smooth section and sweepback section, and sweepback section includes lower anti-blade tip, and lower anti-blade tip has taper
End, one side agent structure consolidate, and without excessive segmentation, on the other hand this kind design reduces the induced velocity of blade, and
Also evenly, the tip vortex position for also making blade more on the lower, advantageously reduces paddle-vortex interaction for the distribution of induced velocity, flight
Efficient, the overall power of aircraft is low;
2nd, using biconvex profile, and the upper cambered surface bending degree of slip section is than lower camber side bending degree bigger, favorably
In ensureing lower relative thickness, higher lift resistance ratio is obtained;
3rd, blade is using positive torsion, and maximum twist angle is 15 degree, is conducive to change the angle of attack of blade, and then adjusts pneumatic
The exhibition of load, so as to improve the lift of blade, is conducive to raising efficiency to distribution;
4th, the configuration of the present invention is simple, easy to process, pneumatic efficiency is high, is easy to wide popularization and application.
Description of the drawings
Attached drawing is used to provide further understanding of the present invention, and a part for constitution instruction, the reality with the present invention
Example is applied together for explaining the present invention, is not construed as limiting the invention.In the accompanying drawings:
Fig. 1 is schematic structural view of the invention;
Fig. 2 is schematic front view of the present invention;
Fig. 3 is sweepback section detailed schematic;
Fig. 4 is schematic diagram of the embodiment of the present invention;
Fig. 5 is B-B direction diagrammatic cross-section in Fig. 4;
Fig. 6 be in Fig. 4 C-C to diagrammatic cross-section;
Fig. 7 be in Fig. 4 E-E to diagrammatic cross-section;
Fig. 8 be in Fig. 4 F-F to diagrammatic cross-section;
Fig. 9 be in Fig. 4 G-G to diagrammatic cross-section;
Figure 10 be in Fig. 4 H-H to diagrammatic cross-section;
Figure 11 be in Fig. 4 I-I to diagrammatic cross-section;
Figure 12 be in Fig. 4 J-J to diagrammatic cross-section;
Figure 13 be in Fig. 4 K-K to diagrammatic cross-section;
Figure 14 be in Fig. 4 L-L to diagrammatic cross-section;
Figure 15 be in Fig. 4 M-M to diagrammatic cross-section;
Figure 16 be in Fig. 4 N-N to diagrammatic cross-section;
Figure 17 be in Fig. 4 O-O to diagrammatic cross-section;
Figure 18 be in Fig. 4 P-P to diagrammatic cross-section;
Figure 19 is pulling force-power lab diagram of rotor blade;
In figure:1. rotational positioning hole, 2. leading edges, 3. rears, 4. sweepback sections, arc in 41. sweepback, arc under 42. sweepback, under 5.
Anti- blade tip, cambered surface on 6., 7. lower camber sides, 8. strings of a musical instrument, 9. smooth sections;
STA:Anti- blade tip, ST under sweepback taper:Sweepback taper blade tip, R:Rectangle blade tip.
Specific embodiment
For those skilled in the art is made to more fully understand technical scheme of the present invention, below in conjunction with the accompanying drawings and specific embodiment party
Formula is described in further detail the present invention.
As shown in Figures 1 to 4, the embodiment of the present invention provides a kind of high-efficient low-noise rotor, and including blade, blade includes rotation
Location hole 1, rotational positioning hole 1 are connected with integrally formed smooth section 9 and sweepback section 4 in turn;Sweepback section 4 includes lower anti-blade tip 5,
Sweepback section 4 further includes in sweepback arc 42 under arc 41 and sweepback, and the intersection of arc 42 forms taper end under arc 41 and sweepback in sweepback.
Preferably, smooth section 9 includes upper cambered surface 6 and lower camber side 7, and the bending degree of upper cambered surface 6 is more than the bending of lower camber side 7
Degree can obtain higher lift resistance ratio, and this kind of blade is biconvex profile, simple in structure, easy to process.Blade includes reference
Chord length, the thickness of blade meet:Maximum blade thickness/chord length≤8% is conducive to ensure smaller resistance.The sweepback of sweepback section 4
Angle is 22 degree, it is possible to reduce profile drag power improves lift distribution and weakens paddle-vortex interaction.Under anti-blade tip 5 inverted diherdral be 33
Degree, the design of lower anti-blade tip 5 not only reduce the induced velocity of blade, but also are distributed more compared with the induced velocity of ordinary rectangular blade
Become uniform.Blade includes leading edge 2 and rear 3, and leading edge 2 can be reduced wave resistance, be made the oblique shock wave of the attached body of generation with generation using sharp leading edge
For in vitro normal shock wave.Blade includes the string of a musical instrument 8, and blade forms torsion angle along the just torsion of the string of a musical instrument 8, and torsion angle is no more than 15 degree,
Be conducive to change the effective angle of attack extended to each section, and then the exhibition for adjusting aerodynamic loading is induced to distribution so as to reduce wing
Resistance improves airfoil lift.
Specifically, as shown in Fig. 4 to Figure 18, the distance between the leading edge 2 of blade and rear 3 are by the straight of rotational positioning hole 1
Diameter is gradually expanded with smooth curve, reaches maximum at intermediate cross-section, then be gradually reduced, until tail portion sweepback section 4.From rotation
At the center of location hole 1 along the string of a musical instrument 8 with 20 centimeters for interval respectively to blade section, if Fig. 5 to Figure 18 is as it can be seen that B-B direction cuts open
The torsion angle in face is 7 degree, 40.23 centimeters of chord length, and the torsion angle of C-C to section is maximum, is 15 degree, 52.8 centimeters of chord length, E-E
To section torsion angle for 14 degree, 66.37 centimeters of chord length, F-F to the torsion angle of section be 13 degree, 71.02 centimeters of chord length, blade
Reach 5.7 centimeters of maximum gauge at F-F, relative thickness is maximum gauge and the ratio of chord length, i.e. 5.7/71*100%=
8%, G-G are 12 degree to the torsion angle of section, and chord length is 72.58 centimeters, and H-H is 11 degree to the torsion angle of section, and chord length is
73.35 centimeters, torsion angle from I-I to section for 10 degree, chord length is 70.27 centimeters, J-J to the torsion angle of section be 9 degree, chord length
It it is 63.8 centimeters, K-K is 8 degree to the torsion angle of section, and 58.57 centimeters of chord length, L-L is 7 degree to the torsion angle of section, and chord length is
55.09 centimeters, M-M is 6 degree to the torsion angle of section, and chord length is 51.7 centimeters, and N-N is 5 degree to the torsion angle of section, and chord length is
48.46 centimeters, torsion angle from O-O to section for 4 degree, chord length is 45.29 centimeters, P-P to the torsion angle of section be 3 degree, chord length
It is 42.65 centimeters;As it can be seen that the torsion angle of blade is from small to large, after reaching 15 degree of maximum value, then it is gradually reduced, corresponding chord length
Also first become larger, after successively decrease.
According to the blade that this programme is processed, in configuration different from traditional rectangle blade, manufacture is more convenient, and cost is more
Controllably;As shown in Fig. 1 to Figure 18, biconvex profile is related to obtain higher lift resistance ratio, and traditional round end aerofoil profile is in Supersonic
Detached shock wave can be generated in fast air-flow, and this wing makes the oblique shock wave of the attached body of generation to reduce wave resistance using sharp leading edge
To replace in vitro normal shock wave.Wave resistance is square directly proportional with relative thickness, therefore resistance is smaller.
As shown in Fig. 4 to Figure 19, the inverted diherdral of blade is 33 degree, and angle of sweep is 22 degree, and taper ratio is 20/23, comparison
Traditional rectangle slurry point, it is lower instead not only to reduce the induced velocity of blade but also more uniform compared with the induced velocity distribution of rectangle.
In addition lower anti-slurry point can make tip vortex position more downward, therefore the slurry of more traditional rectangle in terms of slurry-vortex interaction is weakened point is more
Favorably.And the design of sweepback taper slurry point can reduce profile drag power, improves lift distribution and weaken slurry-vortex interaction.Comparison
Traditional rectangle slurry point and sweepback taper slurry point (slurry point is not lower anti-), when pulling force is identical, and rotor other parameter is identical, power is most
It is small, it can be obtained by the experimental data of Fig. 2, power ratio rectangle blade reduces 3%.When flying speed is larger, 2 sweepback of leading edge can cause
Power loss caused by compressibility reduces.
The foregoing is only a preferred embodiment of the present invention, is not intended to restrict the invention, although with reference to aforementioned reality
Example is applied the present invention is described in detail, it for those skilled in the art, still can be to aforementioned each implementation
Technical solution recorded in example modifies or carries out equivalent replacement to which part technical characteristic.All essences in the present invention
With within principle, any modification, equivalent replacement, improvement and so on should all be included in the protection scope of the present invention god.