CN207991788U - A kind of aerofoil profile sideway oscillation flow tunnel testing device - Google Patents
A kind of aerofoil profile sideway oscillation flow tunnel testing device Download PDFInfo
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- CN207991788U CN207991788U CN201820578724.8U CN201820578724U CN207991788U CN 207991788 U CN207991788 U CN 207991788U CN 201820578724 U CN201820578724 U CN 201820578724U CN 207991788 U CN207991788 U CN 207991788U
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Abstract
The utility model discloses a kind of aerofoil profile sideways to vibrate flow tunnel testing device, including mounting seat, motor, U-shaped strut, aerofoil profile model, it is connected separately with rectification wing tip on two ends of the aerofoil profile model, several dynamic pressure measurement holes and static pressure measured hole are set on the aerofoil profile model, several pressure sensors are provided in the aerofoil profile model, the angular displacement sensor at aerofoil profile model end constitutes position feedback two close cycles servo-control system with the photoelectric encoder at AC servo motor end；The utility model solve can not directly carry out at present aerofoil profile sideway oscillation（Dynamic plunders effect）The problem of research, in order to obtain wind energy conversion system more comprehensively and accurately load value, obtain the design scheme of multiple-objection optimization, the affecting laws for studying sideway oscillation to wind mill airfoil dynamic load characteristic are needed, this will be of great significance to the design of major diameter wind energy conversion system and construction MW class wind turbine group.
Description
Technical field
The present invention relates to wind tunnel test fields, vibrate flow tunnel testing device more particularly, to a kind of aerofoil profile sideway.
Background technology
The actual motion process of large scale wind power machine is very complicated, and blade or aerofoil profile are usually operated under dynamic stall state, moves
State stall is a serious non-linear, unsteady pneumatic phenomenon, is also lacked at present to the deep of unsteady stall aerodynamic characteristic
Understand, it can not comprehensive accurate description dynamic stall phenomenon and rule.Dynamic oscillation process is usually associated with pitching（The angle of attack is periodical
Variation）And sideway（Angle of sweep cyclically-varying）It is carried out at the same time, vertical dip mining can cause wind energy conversion system practical limit load higher than setting
Meter and calculated value, and may reduce ultimate load when weaving majority.The rank that many dynamic problems were not known in the past
Section, do not stint in engineering and use full design content to retain sovereignty over a part of the country as cost to increase blade construction weight, so usually ignoring sideway oscillation
Influence, both at home and abroad in terms of the research of aerofoil profile dynamic characteristic is concentrated mainly on vertical dip mining.In order to improve Blade Properties, drop
Low blades weight, aerodynamic loading assessment should be more accurate, to reduce design margin.
Currently, have the research for fixing vertical dip mining or aerofoil profile Radial Flow under angle of sweep about rotor-blade airfoil band on a small quantity,
It is regarded as the research of the static state " plunder effect (Sweep Effect) " constant about angle of sweep：The three-dimensional non-steady of airfoil
Boundary layer separation shows significantly different feature compared to the separation in the case of two-dimensional flow.However, the shimmy process of wind energy conversion system is
Along with the continually changing dynamic in angle of sweep " plunderring effect ", shimmy and other non-stationary motions coupling can cause stall more multiple
It is miscellaneous.So far, the technology for directly carrying out the oscillation of aerofoil profile sideway and research are there is no in open source literature, in order to obtain wind energy conversion system more
Comprehensively and accurately load value obtains the design scheme of multiple-objection optimization, needs to study sideway oscillation to aerofoil profile dynamic load characteristic
Affecting laws.Wind tunnel test is to recognize the main means of aerofoil profile dynamic stall characteristic and flow mechanism, in consideration of it, establishing aerofoil profile
Vertical dip mining and sideway vibrate dynamic wind-tunnel research technique, carry out wind mill airfoil dynamic stall attribute testing research, based on setting
The electronics external trigger device of meter has expanded fluidised form synchro measure means, realizes wind-tunnel incoming, angle of attack and dynamic pressure number
According to real-time synchronization acquisition, can be wind mill airfoil dynamic " plunderring effect " research provide important technology support, it will to promotion
Chinese large-sized wind energy conversion system autonomous Design research and development ability plays vital supporting role.
Invention content
The purpose of the present invention is to obtain wind energy conversion system more comprehensively and accurately load value, obtain the design of multiple-objection optimization
Scheme, the oscillation of research sideway provide important technical to the affecting laws of wind mill airfoil dynamic load characteristic, establish aerofoil profile
Sideway vibrates dynamic wind-tunnel research technique, and the research that effect can be plunderred for the dynamic of wind mill airfoil provides technical support, provides one
Kind aerofoil profile sideway vibrates flow tunnel testing device.
To achieve the goals above, the present invention adopts the following technical scheme that：
A kind of aerofoil profile sideway oscillation flow tunnel testing device, including a mounting seat being fixed on wind-tunnel outer wall, it is described
There are one motors, the power output shaft of motor to enter in wind-tunnel across wind-tunnel outer wall and connect a U for setting in mounting seat
The opening both ends of shape strut, open end towards wind-tunnel center and the U-shaped strut of the U-shaped strut are connected on aerofoil profile model；
Rectification wing tip is connected separately on two ends of the aerofoil profile model, along symmetrical section on the aerofoil profile model
Several dynamic pressure measurement holes of a circle are provided with, the side in dynamic pressure measurement hole is provided with a circle several static pressures
Measured hole,
Several pressure sensors, the angular displacement sensor at aerofoil profile model end and friendship are provided in the aerofoil profile model
The photoelectric encoder at flow servo motor end constitutes position feedback two close cycles servo-control system.
In the above-mentioned technical solutions, thrust bearing, the thrust bearing are provided between the output revolving shaft and U-shaped strut
It is fixed in mounting seat, one end of thrust bearing is connect with U-shaped strut, and the other end connects the output revolving shaft of motor.
In the above-mentioned technical solutions, the output revolving shaft of the motor is not subject to the axial tension of U-shaped strut, and only power output
Square.
In the above-mentioned technical solutions, the aerofoil profile model is three stage structure, the rectifying wings of intermediate mold segment and both ends
Point, the rectification wing tip can be replaced.
In the above-mentioned technical solutions, the rectification wing tip includes three kinds of winglet, the blunt wing and tapered wing wing tip forms.
In the above-mentioned technical solutions, two connecting pins of the U-shaped strut are symmetrically connected on aerofoil profile model, the U-shaped
It is respectively arranged with angle block gauge between two connecting pins of strut and aerofoil profile model.
In the above-mentioned technical solutions, company is fixed in two connecting pins of the U-shaped strut and the different location of angle block gauge
It connects, to change the angle of attack of aerofoil profile model.
In the above-mentioned technical solutions, the U-shaped strut is integrated design, and U-shaped strut is non-smooth surface, the U-shaped
It is cavity structure in the bar of strut, the cavity structure is communicated in aerofoil profile model.
In the above-mentioned technical solutions, the aerofoil profile model is cavity structure, and pressure sensor is arranged in cavity, the sky
Dismountable cover plate is provided at cavity configuration.
In the above-mentioned technical solutions, the U-shaped strut is connected to the pressure face of aerofoil profile model.
In conclusion by adopting the above-described technical solution, the beneficial effects of the invention are as follows：
The present invention solve can not directly carry out at present aerofoil profile sideway oscillation（Dynamic plunders effect）The problem of research, in order to obtain
Wind energy conversion system more comprehensively and accurately load value is obtained, the design scheme of multiple-objection optimization is obtained, needs to study sideway oscillation to wind-force
The affecting laws of airfoil type dynamic load characteristic, this will be of great significance to building MW class wind turbine group, the present invention
Wind mill airfoil sideway oscillation unsteady aerodynamic characteristic wind- tunnel investigation means are established, can be that the dynamic of wind mill airfoil plunders effect
The research answered provides important technology support, it will most important to promoting the performance of Chinese large-sized wind energy conversion system autonomous Design research and development ability
Supporting role.
Description of the drawings
Examples of the present invention will be described by way of reference to the accompanying drawings, wherein：
Fig. 1 is the structural schematic diagram of the present invention；
Fig. 2 is a kind of structural schematic diagram of the present invention；
Wherein：1 is wind-tunnel wall, and 2 be motor, and 3 be mounting seat, and 4 be U-bracket, and 5 be aerofoil profile model, and 6 be angle block gauge, 7
It is wing tip.
Specific implementation mode
All features disclosed in this specification or disclosed all methods or in the process the step of, in addition to mutually exclusive
Feature and/or step other than, can combine in any way.
As shown in Fig. 1, entire sideway shaking test device includes such as lower component：
Motor part：Main purpose exports pure oscillation campaign, the characteristics of motion：β=β 0 +β 1 sin2πft；" electric cam "
Replace mechanical cam, not only simplifies mechanical device structure, also achieve the stepless variation of frequency of oscillation and oscillation angle.
Thrust bearing：Model dead weight, strut dead weight and model normal direction aerodynamic force etc. act on thrust bearing, motor
It is not subjected to axial force.Main purpose is so that motor is not subjected to axial force and only output torque, and then drive integral type U-shaped branch
Bar.
Transmission shaft component：Across upper hole wall, the U-shaped strut torque of drive motor means being output in test section hole.
Erection support：Motor is fixedly mounted on to the center position of hole wall on test chamber, ensures the model position of connection
Central area in test section flow field.
Angular displacement sensor：Dynamic test angular displacement signal is important test parameters, and when acquisition wants and pressure sensor
The pneumatic load synchronous recording of impression realizes that synchronizing for pressure sensor signal is adopted with the displacement signal trigger data acquisition system
Collection.It is installed on the photoelectric coding of the output signal and AC servo motor end of the potentiometer type angular displacement sensor at test model end
Device output signal acts on motion controller simultaneously, constitutes position feedback two close cycles servo-control system, realizes oscillating movement rule
Rule accurately controls；The absolute value analog signal of angular displacement sensor output accesses dynamic together with dynamic pressure transducer signal
Data collecting system realizes the synchronous acquisition of angular displacement signal and corresponding dynamic pressure signal, strict guarantee dynamic test number
According to correspondence.
Integral type U-shaped strut：In order to reduce interference of the strut to aerofoil profile dynamic pressure measurement, strut is designed to U-shaped, is propped up
The both ends that bar separates are separately connected the aerofoil profile both ends far from model center area, the levelness that sideway shaking test install aerofoil profile with
Symmetry requires high, and strut is fabricated using integral type, reduction assembling link, to improve model installation accuracy and strut
Whole rigidity.Strut surface is non-smooth surface, annular knurl technique processing strut surface may be used, to weaken flow separation.
Rectification wing tip：Since the model end three-dismensional effect of Airfoil Testing is affected to test result, modelling is
The three stage structure being made of interlude and both ends rectification wing tip, and wing tip structure shape can be replaced according to the different of operating condition of test
Formula shares three kinds of winglet, the blunt wing and tapered wing wing tip forms.
Angle block gauge：Sideway oscillation unsteady aerodynamic characteristic difference of the aerofoil profile under the different angles of attack is larger, different groups of design processing
Angle block gauge can facilitate the Fast transforms of the angle of attack of model.Angle block gauge is designed to the higher pressing block type of positioning accuracy, one end connection
Strut, the coordinate contact surfac of other end link model is tightened connected with screw rod, and briquetting is designed with interior counterbore, ensures stream field
Interference is minimum.As shown in Fig. 2, aerofoil profile model realizes the variation of the angle of attack under the adjusting of angle block gauge.
Built-in type cabling channel：All test cables and pressure measurement pipeline are passed through from the built-in type cabling channel of U-shaped strut, not cruelly
It is exposed in flow fields environment, to avoid the adverse effect of cable and pipeline convection current field uniformity and test repeatability.
Dismountable cover plate:Model opens up dismountable cover plate, ensures the premise in not damage model and pressure sensor
Under, the Fast Installation of designated position pressure sensor and dismounting inside implementation model, and facilitate connecting cable and pressure-measuring pipe.
Anti- die-filling type：Experimental study shows that airfoil suction side is more sensitive to support interferences, therefore this sideway oscillation device
It is all made of the anti-configuration filled of model with test method, i.e. strut is directly connected to the pressure face of aerofoil profile.
Dynamic pressure measurement hole：Dynamic pressure measurement hole is arranged in the intermediate symmetry section of model, built-in differential pressure type dynamic
Pressure sensor can obtain the pressure fluctuation of airfoil surface in real time, and integrable obtains every dynamic aerodynamics/power of aerofoil profile
Moment coefficient.
Static pressure measured hole：It is mainly used to examine the accurate testing degree of dynamic pressure transducer.Static pressure
Hole measurement and integrate acquisition model Static Gas power/forces square and dynamic pressure transducer measure and integrate acquisition model it is quiet
State aerodynamic force/torque together, is complemented one another and is verified.
The present invention mainly carries out the research of aerofoil profile sideway shaking test, and aerofoil profile sideway vibrates yaw angle changing rule：β=β 0 +β 1 sin2πft；
Aerodynamic characteristic data are vibrated in order to obtain aerofoil profile sideway, are tested in different initial yaw anglesβ 0 , oscillation amplitudeβ 1 、
Frequency of oscillationf, the test windVWith the balance angle of attackα 0 Lower development.
Specific test method is as follows：Driving force is provided by the motor pushed up mounted on hole, using " electric cam " technology generation
For mechanical cam, the sideway oscillating movement of implementation model.Driving motor, gear reducer and transmission shaft component are mounted on above the body of hole
On motor support base, use the configuration of " the symmetrical middle section of model for dynamic pressure measurement section, strut link model both ends ", design according to
According to being：A. strut places both ends, pressure tap can farthest reduce strut and model end three-dismensional effect to dynamic between two parties
The aerodynamic interference of pressure measurement；B. when model weaving, the linear velocity component of the pressure measurement section of center in direction of rotation is minimum
Can even it ignore, convenient for changing just for yaw angle periodic sinusoidal, i.e., " plunderring effect ", problem directly conducts a research.
Concrete methods of realizing is：Model, across in wind-tunnel center, is vibrated transmission shaft component by sideway and is connected mould by level
Type " u "-shaped strut drives aerofoil profile to do pure oscillation；Sideway is vibrated in the different fixation angles of attack（α 0 =-4 ° ~ 20 °, it is spaced 3 °）Under
Carry out, the variation of the angle of attack is realized by replacing the angle block gauge between strut and model.The dynamic pressure drawn from model is surveyed
Amount cable and static tube follow model satellite movement together, and ensure the leakproofness of aerofoil profile upper and lower ends.Mould when sideway vibrates
Type uses the straight wing tip such as rectification wing tip replacement to reduce end three-dismensional effect.Dynamic pressure signal collecting and transmitting method is, from mould
By a side end panel lead-out wire cable and with reference to pressure hose inside type, hose is placed in outside hole to provide referenmce atomsphere pressure in turbulence sphere,
Sensor signal cable is quickly connect by J30J-37 types adapter with 8 multiple twin double shield flexible cable 8-2 × 0.15, is realized
The power supply of sensor and signal transmission, power supply are powered by two Tectronix PWS4305 DC power supplies series connection realization ± 5V.The wing
When type sideway vibrates, fluorescence silk thread is pasted on aerofoil profile top airfoil along incoming along spanwise, carries out Dynamic Flow Field characteristic fluorescence silk
Thread test is studied.
Ensure that multichannel synchronousing collection ability, synchronous acquisition parameter include mainly wind using PXI bus data acquisition systems
Hole incoming is total/static pressure, the real-time yaw angle of model, modal pressure data etc..It is acquired aerofoil profile yaw angle as a parameter in real time,
Ensure aerofoil profile yaw angle and 27 pressure datas while acquiring.Force samples are touched using potentiometer any position signal when experiment
Hair, different model frequencies of oscillation, each cycle number of samples is all 256 points, and the sampling period is fixed as 16 periods.After acquisition
Pressure sensor data carry out six rank Fourier filterings and low-pass filtering treatment, then it is average at 1 cycle data, by 1 period
Data carry out six rank least square polynomial fits, and the fixed quantity angle of attack is exported by equiphase angular spacing（256 points）And correspondence
Pressure data.
The processing method of data is carried out with analysis method using conventional method.
The invention is not limited in specific implementation modes above-mentioned.The present invention, which expands to, any in the present specification to be disclosed
New feature or any new combination, and disclose any new method or process the step of or any new combination.
Claims (10)
1. a kind of aerofoil profile sideway vibrates flow tunnel testing device, it is characterised in that the installation bottom being fixed on wind-tunnel outer wall including one
, there are one motors, the power output shaft of motor to enter in wind-tunnel and connect across wind-tunnel outer wall for setting in the mounting seat
A U-shaped strut is connect, the opening both ends of open end towards wind-tunnel center and the U-shaped strut of the U-shaped strut are connected to aerofoil profile mould
In type；
It is connected separately with rectification wing tip on two ends of the aerofoil profile model, is arranged along symmetrical section on the aerofoil profile model
There are several dynamic pressure measurement holes of a circle, the side in dynamic pressure measurement hole is provided with a circle several static pressures measurement
Hole；
It is provided with several pressure sensors in the aerofoil profile model, the angular displacement sensor at aerofoil profile model end is watched with exchanging
The photoelectric encoder for taking motor side constitutes position feedback two close cycles servo-control system.
2. a kind of aerofoil profile sideway according to claim 1 vibrates flow tunnel testing device, it is characterised in that the output revolving shaft
Thrust bearing is provided between U-shaped strut, the thrust bearing is fixed in mounting seat, one end of thrust bearing and U-shaped
Strut connects, and the other end connects the output revolving shaft of motor.
3. a kind of aerofoil profile sideway according to claim 1 vibrates flow tunnel testing device, it is characterised in that according to claim 2
A kind of aerofoil profile sideway vibrates flow tunnel testing device, it is characterised in that the output revolving shaft of the motor is not subject to U-shaped strut
Axial tension, and only output torque.
4. a kind of aerofoil profile sideway according to claim 1 vibrates flow tunnel testing device, it is characterised in that the aerofoil profile model
For three stage structure, the rectification wing tip of intermediate mold segment and both ends, the rectification wing tip can be replaced.
5. a kind of aerofoil profile sideway according to claim 4 vibrates flow tunnel testing device, it is characterised in that the rectification wing tip
Including three kinds of winglet, the blunt wing and tapered wing wing tip forms.
6. a kind of aerofoil profile sideway according to claim 1 vibrates flow tunnel testing device, it is characterised in that the U-shaped strut
Two connecting pins are symmetrically connected on aerofoil profile model, are respectively set between two connecting pins of the U-shaped strut and aerofoil profile model
Angled piece.
7. a kind of aerofoil profile sideway according to claim 6 vibrates flow tunnel testing device, it is characterised in that the U-shaped strut
The different location of two connecting pins and angle block gauge is fixedly connected, to change the angle of attack of aerofoil profile model.
8. vibrating flow tunnel testing device according to a kind of any aerofoil profile sideway of claim 1-3,6-7, it is characterised in that institute
The U-shaped strut stated is integrated design, and U-shaped strut is non-smooth surface, is cavity structure, the sky in the bar of the U-shaped strut
Cavity configuration is communicated in aerofoil profile model.
9. a kind of aerofoil profile sideway according to claim 8 vibrates flow tunnel testing device, it is characterised in that the aerofoil profile model
For cavity structure, pressure sensor is arranged in cavity, and dismountable cover plate is provided at the cavity structure.
10. a kind of aerofoil profile sideway according to claim 1 vibrates flow tunnel testing device, it is characterised in that the U-shaped strut
It is connected to the pressure face of aerofoil profile model.
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| CN201820578724.8U CN207991788U (en) | 2018-04-23 | 2018-04-23 | A kind of aerofoil profile sideway oscillation flow tunnel testing device |
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| CN201820578724.8U CN207991788U (en) | 2018-04-23 | 2018-04-23 | A kind of aerofoil profile sideway oscillation flow tunnel testing device |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108414182A (en) * | 2018-04-23 | 2018-08-17 | 中国空气动力研究与发展中心低速空气动力研究所 | A kind of aerofoil profile sideway oscillation flow tunnel testing device |
| CN110887633A (en) * | 2019-12-25 | 2020-03-17 | 中国航空工业集团公司西安飞机设计研究所 | Elastic gust response wind tunnel test device |
| CN116242578A (en) * | 2023-05-11 | 2023-06-09 | 西北工业大学 | Wing-shaped space flow field display device of string type fluorescent microfilament |
-
2018
- 2018-04-23 CN CN201820578724.8U patent/CN207991788U/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108414182A (en) * | 2018-04-23 | 2018-08-17 | 中国空气动力研究与发展中心低速空气动力研究所 | A kind of aerofoil profile sideway oscillation flow tunnel testing device |
| CN108414182B (en) * | 2018-04-23 | 2023-11-10 | 中国空气动力研究与发展中心低速空气动力研究所 | Wing type yaw oscillation wind tunnel test device |
| CN110887633A (en) * | 2019-12-25 | 2020-03-17 | 中国航空工业集团公司西安飞机设计研究所 | Elastic gust response wind tunnel test device |
| CN116242578A (en) * | 2023-05-11 | 2023-06-09 | 西北工业大学 | Wing-shaped space flow field display device of string type fluorescent microfilament |
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Granted publication date: 20181019 Termination date: 20210423 |