CN109533311A - A kind of high-performance ducted fan - Google Patents
A kind of high-performance ducted fan Download PDFInfo
- Publication number
- CN109533311A CN109533311A CN201811364053.6A CN201811364053A CN109533311A CN 109533311 A CN109533311 A CN 109533311A CN 201811364053 A CN201811364053 A CN 201811364053A CN 109533311 A CN109533311 A CN 109533311A
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- Prior art keywords
- blade
- fan
- duct
- blade fan
- performance
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- 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.)
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C27/00—Rotorcraft; Rotors peculiar thereto
- B64C27/20—Rotorcraft characterised by having shrouded rotors, e.g. flying platforms
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C11/00—Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C11/00—Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
- B64C11/02—Hub construction
- B64C11/14—Spinners
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C11/00—Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
- B64C11/16—Blades
- B64C11/18—Aerodynamic features
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C11/00—Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
- B64C11/16—Blades
- B64C11/20—Constructional features
Abstract
This application provides a kind of high-performance ducted fans, belong to flight vehicle aerodynamic design, ducted fan includes duct, the opposing stationary central fairing with duct, it is set to stator vane fixed with duct and central fairing between duct and central fairing and respectively, and the pulp hub radome fairing that is relatively rotatable to each other coaxial with central fairing and the multiple blade fans being set on pulp hub radome fairing, blade fan successively has along spanwise direction from blade root to blade tip there are three region, the torsion angle perseverance of blade fan is 7 °~9 ° in first area, the torsion angle perseverance of blade fan is 0 ° in third region, the blade fan torsion angle of second area between the terminal of first area and the starting point in third region is linear change, D is blade fan diameter.The application can be realized the geometry optimization of blade fan, duct and stator vane on pneumatic, and in the case where generating identical liter/thrust, the power reduction of consumption can be obviously improved hovering performance under identical pulling force.
Description
Technical field
The application belongs to flight vehicle aerodynamic design field, in particular to a kind of high-performance ducted fan.
Background technique
Ducted fan is that aircraft commonly rises/push system, can produce unidirectional liter/thrust, realizes aircraft vertical
Landing, balance and flight forward.Compared with the liters/push system such as rotor, propeller, ducted fan has easy to maintenance, use
Safe, compact-sized, the more low technical characterstic of noise level is one of the Main way for promoting liter/push system efficiency.Duct
On the basis of the design of fan will guarantee duct space and structure space, aerodynamic performance, weight, maintainability are comprehensively considered
Equal many factors, process is mutually coordinated, overall balance is just able to achieve.
The ducted fan of the prior art mechanical property, in terms of existing defects, also have optimization space.
Summary of the invention
There is provided a kind of high-performance ducted fans for the purpose of the application, any of the above-described to solve the problems, such as or mitigate.
The technical solution of the application is: a kind of high-performance ducted fan, and the ducted fan includes duct, opposite with duct
Static central fairing is set to stator fixed with duct and central fairing between duct and central fairing and respectively
It blade, and the pulp hub radome fairing that is relatively rotatable to each other coaxial with the central fairing and is set to more on pulp hub radome fairing
A blade fan, wherein the blade fan successively has along spanwise direction from blade root to blade tip there are three region, in first area
The torsion angle perseverance of interior blade fan is 7 °~9 °, and the torsion angle perseverance of blade fan is 0 ° in third region, in first area
The blade fan torsion angle of second area between terminal and the starting point in third region is linear change, and D is blade fan diameter.
In one embodiment of the application, the terminal of the first area is 0.18D~0.22D, the third region
Starting point is 0.4D~0.46D, and D is blade fan diameter.
In one embodiment of the application, the duct (1) include the lip being sequentially connected, etc. straight sections and diffuser,
In, the lip is circular arc lines, and the equal straight sections are the straight line parallel with duct axis, and the diffuser is and blade fan
Rotary shaft at default diffusion angle straight line.
In one embodiment of the application, circular arc lines radius R=0.05D~0.15D of the lip, diffuser it is pre-
If -12 ° of angle of flare ψ=8 °, and length L the > 0.5D, D of diffuser are blade fan diameter.
In one embodiment of the application, there is gap delta between the blade fan and duct, the gap delta is not more than
0.005D, D are blade fan diameter.
In one embodiment of the application, the profile thickness of blade fan perseverance before the terminal of first area is
12.5%-13.5% is 9%-10% at blade tip, and the terminal in first area is opened up along blade to linear change between blade tip
Change.
In one embodiment of the application, the rotor hub fairing system and central fairing are the cylindrical body with same radius
Structure, and radius is not less than 0.15D, D is blade fan diameter.
In one embodiment of the application, the blade quantity phase of the blade quantity of the stator vane and the blade fan
Together, the gap and between the stator vane and shown blade fan is not more than 0.1D, and D is blade fan diameter.
In one embodiment of the application, the section and duct axis of the stator vane have angleThe angle
Deflection direction be duct axis be directed toward stator vane string direction, angleDeflection direction and blade fan rotation side
To opposite.
In one embodiment of the application, the angleIt is distributed as follows:
Wherein, a=-342.9D-50, b=285.7D+83.3, c=-85.7D-37.5, d=17.1D+4.2, e=-
0.23D-0.2,
In formula: r is variable, and R is blade fan radius, and D is blade fan diameter.
It is excellent that the high-performance ducted fan of the application can be realized the geometry of blade fan, duct and stator vane on pneumatic
Change, in the case where generating identical liter/thrust, the power of consumption is reduced, and hovering performance can be obviously improved under identical pulling force.
Detailed description of the invention
In order to illustrate more clearly of technical solution provided by the present application, attached drawing will be briefly described below.It is aobvious and easy
Insight, drawings discussed below are only some embodiments of the present application.
Fig. 1 is the high-performance ducted fan sectional view and parameter definition of the application；
Fig. 2 is that the high-performance ducted fan of the application constitutes schematic diagram；
Fig. 3 is the section torsion angle distribution schematic diagram of the fan blade of the application；
Fig. 4 is the sectional thickness distribution schematic diagram of the fan blade of the application；
Fig. 5 is the diagrammatic cross-section of the fan blade of the application；
Fig. 6 is the stator section angle distribution schematic diagram of the application；
Fig. 7 is the ducted fan of the application compared with conventional ducted fan performance.
Appended drawing reference:
1- duct, 11- lip, the straight sections such as 12-, 13- diffuser；
2- blade fan；
3- rotor hub fairing system；
4- central fairing；
5- stator vane；
6- duct axis.
Specific embodiment
To keep the purposes, technical schemes and advantages of the application implementation clearer, below in conjunction in the embodiment of the present application
Attached drawing, technical solutions in the embodiments of the present application is further described in more detail.
In the description of the present application, term " center ", " longitudinal direction ", " transverse direction ", "front", "rear", "left", "right", "vertical",
The orientation or positional relationship of the instructions such as "horizontal", "top", "bottom", "inner", "outside" is to be closed based on orientation described in attached drawing or position
System is merely for convenience of description the application and simplifies description, rather than the device or element of indication or suggestion meaning must have
Specific orientation is constructed and operated in a specific orientation, therefore should not be understood as the limitation to the application protection scope.
In order to solve in the prior art, in the case that ducted fan generates identical liter/thrust, consumed power is higher
In the case of, the application proposes a kind of high-performance ducted fan, by optimizing the geometric shape of ducted fan, comprehensive duct, blade
It with the geometric parameter and layout of stator, realizes in the case where generating identical liter/thrust, consumes lower power, improve duct
The pneumatic efficiency of fan.
High-performance ducted fan structural schematic diagram as depicted in figs. 1 and 2, the high-performance ducted fan of the application are forming
On include: a non-rotary duct 1, with duct 1 be coaxially disposed multiple blade fans 2, with blade fan 2 rotate together with and
The rotor hub fairing system 3, fixed central fairing 4 and outer end for wrapping up propeller hub are connect with duct 1 and inner end and central fairing 4
Multiple stator vanes 5 of connection.
As shown in figure 3, the optimization for blade fan 2 includes: blade fan 2 in the optimization of high-performance ducted fan
Successively have from blade root to blade tip along spanwise direction there are three region, in first area the torsion angle perseverance of blade fan be 7 °~
9 °, the torsion angle perseverance of blade fan is 0 ° in third region, between the terminal of first area and the starting point in third region
The blade fan torsion angle of second area is linear change, and D is blade fan diameter.The radial Zhan Xiangsuo with the application in figure
The direction of reference is identical, but radial position is at zero axial location for referring generally to rotor hub fairing system 4 in figure, and by blade fan 2
Blade root generally has a distance with the axis of rotor hub fairing system 4, therefore is the application at about 0.15 position of radial position in figure
Blade fan 2 blade root at.
It in this application, include: that the terminal of first area is located at for advanced optimizing for above-mentioned blade fan 2
It is as shown in the figure 0.2D in the section 0.18D~0.22D, the starting point in third region is located in the section of 0.4D~0.46D, figure
Shown in be 0.45D, D be blade fan diameter.
In this application, the structure of duct 1 is optimized:
1) inner wall of duct 1 successively by lip 11, etc. straight sections 12 be connected with diffuser 13 and constitute, wherein lip 11 is
Circular arc type lines, waiting straight sections 12 is the straight line parallel with rotation center (duct axis 6), and the linear of diffuser 13 is and blade wind
Fan 2 rotary shaft at certain diffusion angle straight line；
2) as Fig. 2, blade fan 2 and the gap delta of duct 1 are located at no more than 0.005D, the arc radius R of lip 11
Between 0.005D~0.15D, optimal case is close to 0.1D, and the angle of flare ψ of diffuser 13 is located between 8 °~12 °, optimal
Scheme is close to 10 °, and the length L of diffuser 13 is not less than 0.5D, and optimal case is that take close to 0.5D, D be blade fan diameter,
By the combination of above-mentioned geometry, it can be achieved that the optimal pneumatic efficiency of duct；
3) such as Fig. 3, blade fan 2 are connect with the propeller hub being wrapped in rotor hub fairing system 3, and the torsion angle of blade fan is whole
Be about 8 ° close to the position 0.2D torsion angle in nonlinear change, be about 0 ° close to the position 0.45D torsion angle, in 0.2D and
Torsion angle changes linearly between 0.45D, keeps constant in 0.45D to blade tip torsion angle.
4) such as Fig. 4, the sectional thickness of blade fan 2 is being about 12.5% close to 0.2D (i.e. the terminal of first area) position
~13.5%, it is as shown in the figure 13%, is about 9%~10% in blade tip, be as shown in the figure 10%, in 0.2D to edge between blade tip
Blade is opened up to linear change；
5) rotor hub fairing system 3 and central fairing 4 are cylindrical structure, radius having the same, and radius is not less than
0.15D, D are blade fan diameter；
6) such as Fig. 5, stator vane 5 are fixed multiple leaflet constructs, and blade quantity is identical as blade fan 2, blade fan 2
Blade outer end connect with duct 1, inner end and central fairing 4 connection, the gap M between stator vane 5 and blade fan 2 is not
It is blade fan diameter greater than 0.1D, D.
7) such as Fig. 6, there are included angle, included angle direction and blade fans 2 for the section and duct axis 6 of stator vane 5
Direction of rotation can promote duct aeroperformance on the contrary, be defined as positive direction.In the application, non-constant stator vane 2 is defined
Section and 6 angle of duct axis, angle are distributed as follows:
Wherein, a=-342.9*D-50, b=285.7*D+83.3, c=-85.7*D-37.5, d=17.1*D+4.2, e
=-0.23*D-0.2；
In formula, r is variable, and R is blade fan radius, and D is blade fan diameter.
The geometry that the high-performance ducted fan of the application passes through complex optimum duct 1, blade fan 2 and stator vane 5 etc.
Parameter and layout have been obviously improved the performance of ducted fan.
In order to verify the application high-performance ducted fan performance, by high-performance ducted fan to the application and often
10 blades of rule are compared using the hovering performance of the ducted fan of NACA23012 aerofoil profile, to examine the effect of the application.
The hovering performance FM of ducted fan is defined by following formula:
Wherein, T is ducted fan total pulling force, and P is fan power, and ρ is atmospheric density, and S is fan area.
Such as Fig. 7, by comparison, the high-performance ducted fan of the application can mention under identical pulling force with conventional ducted fan
Rising hovering performance is more than 6%.
The above, the only specific embodiment of the application, but the protection scope of the application is not limited thereto, it is any
Within the technical scope of the present application, any changes or substitutions that can be easily thought of by those familiar with the art, all answers
Cover within the scope of protection of this application.Therefore, the protection scope of the application should be with the scope of protection of the claims
It is quasi-.
Claims (10)
1. a kind of high-performance ducted fan, which is characterized in that the ducted fan includes duct (1), opposing stationary with duct (1)
Central fairing (4), be set between duct (1) and central fairing (4) and respectively with duct (1) and central fairing
(4) fixed stator vane (5), and the pulp hub radome fairing (3) that is relatively rotatable to each other coaxial with the central fairing (4) and
The multiple blade fans (2) being set on pulp hub radome fairing (3), wherein the blade fan (2) along spanwise direction from blade root extremely
Blade tip successively has there are three region, and the torsion angle perseverance of blade fan is 7 °~9 ° in first area, the blade in third region
The torsion angle perseverance of fan is 0 °, and the blade fan of the second area between the terminal of first area and the starting point in third region is turned round
Corner is linear change, and D is blade fan diameter.
2. high-performance ducted fan as described in claim 1, which is characterized in that the terminal of the first area be 0.18D~
0.22D, the starting point in the third region are 0.4D~0.46D, and D is blade fan diameter.
3. the high-performance ducted fan as described in claim 1 to 2 is any, which is characterized in that the duct (1) includes successively phase
Even lip (11), etc. straight sections (12) and diffuser (13), wherein the lip (11) be circular arc lines, it is described grade straight sections
It (12) is the straight line parallel with duct axis (6), the diffuser (13) is the rotary shaft with blade fan (2) into default diffusion
The straight line of angle.
4. high-performance ducted fan as claimed in claim 3, which is characterized in that the circular arc lines radius R of the lip (11)
=0.05D~0.15D, default -12 ° of angle of flare ψ=8 ° of diffuser (13), and the length L of diffuser (13) are not less than 0.5D,
D is blade fan diameter.
5. high-performance ducted fan as described in claim 1, which is characterized in that between the blade fan (2) and duct (1)
With gap delta, the gap delta is not more than 0.005D, and D is blade fan diameter.
6. high-performance ducted fan as described in claim 1, which is characterized in that the profile thickness of the blade fan (2) exists
Permanent before the terminal of first area is 12.5%-13.5%, is 9%-10% at blade tip, first area terminal to blade tip it
Between open up along blade to linear change.
7. high-performance ducted fan as described in claim 1, which is characterized in that the rotor hub fairing system (3) and center rectification
Covering (4) is the cylindrical structure with same radius, and radius is not less than 0.15D, and D is blade fan diameter.
8. high-performance ducted fan as described in claim 1, which is characterized in that the blade quantity of the stator vane (5) with
The blade quantity of the blade fan (2) is identical, and the gap between the stator vane (5) and shown blade fan (2) is not
It is blade fan diameter greater than 0.1D, D.
9. high-performance ducted fan as described in claim 1, which is characterized in that the section and duct of the stator vane (5)
Axis (6) has angleThe angleDeflection direction be duct axis (6) be directed toward stator vane (5) string direction,
AngleDeflection direction it is opposite with the direction of rotation of blade fan (2).
10. high-performance ducted fan as claimed in claim 9, which is characterized in that the angleIt is distributed as follows:
Wherein, a=-342.9D-50, b=285.7D+83.3, c=-85.7D-37.5, d=17.1D+4.2, e=-0.23D-
0.2,
In formula: r is variable, and R is blade fan radius, and D is blade fan diameter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811364053.6A CN109533311B (en) | 2018-11-16 | 2018-11-16 | High-performance ducted fan |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811364053.6A CN109533311B (en) | 2018-11-16 | 2018-11-16 | High-performance ducted fan |
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| Publication Number | Publication Date |
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| CN109533311A true CN109533311A (en) | 2019-03-29 |
| CN109533311B CN109533311B (en) | 2021-02-26 |
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ID=65848002
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811364053.6A Active CN109533311B (en) | 2018-11-16 | 2018-11-16 | High-performance ducted fan |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110513217A (en) * | 2019-09-05 | 2019-11-29 | 中国航天空气动力技术研究院 | A kind of unmanned plane ducted fan dynamical system |
| CN111776209A (en) * | 2020-07-17 | 2020-10-16 | 王东明 | Electronic many rotors plant protection unmanned aerial vehicle |
| WO2021079687A1 (en) * | 2019-10-24 | 2021-04-29 | 株式会社Ｓｕｂａｒｕ | Disc-type vertical take-off and landing aircraft |
| CN114435585A (en) * | 2022-01-28 | 2022-05-06 | 清华大学 | Variable pitch fan and pitch control method thereof |
| KR20220120267A (en) * | 2021-02-23 | 2022-08-30 | 국방과학연구소 | Aircraft with asymmetric ducted fan |
| CN116124407A (en) * | 2023-04-10 | 2023-05-16 | 中国空气动力研究与发展中心低速空气动力研究所 | Test method for obtaining influence of radar wake on aerodynamic characteristics of helicopter tail piece |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101973391A (en) * | 2010-10-15 | 2011-02-16 | 北京理工大学 | Lip and spread angle variable efficient duct |
| CN102745328A (en) * | 2012-07-13 | 2012-10-24 | 北京理工大学 | Bypass with tip eddy-current confinement effect |
| CN106741858A (en) * | 2016-12-06 | 2017-05-31 | 顺丰科技有限公司 | Propeller fin |
| CN206503738U (en) * | 2016-12-29 | 2017-09-19 | 深圳光启合众科技有限公司 | Ducted fan |
| CN206943088U (en) * | 2017-05-03 | 2018-01-30 | 深圳光启合众科技有限公司 | Ducted fan |
| CN207826548U (en) * | 2017-12-29 | 2018-09-07 | 江苏方阔航空科技有限公司 | A kind of high-efficient low-noise rotor |
| CN108545173A (en) * | 2018-06-25 | 2018-09-18 | 北京小米移动软件有限公司 | Blade, propeller and aircraft |
-
2018
- 2018-11-16 CN CN201811364053.6A patent/CN109533311B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101973391A (en) * | 2010-10-15 | 2011-02-16 | 北京理工大学 | Lip and spread angle variable efficient duct |
| CN102745328A (en) * | 2012-07-13 | 2012-10-24 | 北京理工大学 | Bypass with tip eddy-current confinement effect |
| CN106741858A (en) * | 2016-12-06 | 2017-05-31 | 顺丰科技有限公司 | Propeller fin |
| CN206503738U (en) * | 2016-12-29 | 2017-09-19 | 深圳光启合众科技有限公司 | Ducted fan |
| CN206943088U (en) * | 2017-05-03 | 2018-01-30 | 深圳光启合众科技有限公司 | Ducted fan |
| CN207826548U (en) * | 2017-12-29 | 2018-09-07 | 江苏方阔航空科技有限公司 | A kind of high-efficient low-noise rotor |
| CN108545173A (en) * | 2018-06-25 | 2018-09-18 | 北京小米移动软件有限公司 | Blade, propeller and aircraft |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110513217A (en) * | 2019-09-05 | 2019-11-29 | 中国航天空气动力技术研究院 | A kind of unmanned plane ducted fan dynamical system |
| WO2021079687A1 (en) * | 2019-10-24 | 2021-04-29 | 株式会社Ｓｕｂａｒｕ | Disc-type vertical take-off and landing aircraft |
| JP2021066331A (en) * | 2019-10-24 | 2021-04-30 | 株式会社Ｓｕｂａｒｕ | Disc type vertical take-off and landing aircraft |
| JP7284685B2 (en) | 2019-10-24 | 2023-05-31 | 株式会社Subaru | Disc-type vertical take-off and landing aircraft |
| CN111776209A (en) * | 2020-07-17 | 2020-10-16 | 王东明 | Electronic many rotors plant protection unmanned aerial vehicle |
| KR20220120267A (en) * | 2021-02-23 | 2022-08-30 | 국방과학연구소 | Aircraft with asymmetric ducted fan |
| KR102526692B1 (en) | 2021-02-23 | 2023-04-28 | 국방과학연구소 | Aircraft with asymmetric ducted fan |
| CN114435585A (en) * | 2022-01-28 | 2022-05-06 | 清华大学 | Variable pitch fan and pitch control method thereof |
| CN116124407A (en) * | 2023-04-10 | 2023-05-16 | 中国空气动力研究与发展中心低速空气动力研究所 | Test method for obtaining influence of radar wake on aerodynamic characteristics of helicopter tail piece |
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