CN103940575B - A kind of appraisal procedure of wind tunnel test balance based on strain signal energy - Google Patents
A kind of appraisal procedure of wind tunnel test balance based on strain signal energy Download PDFInfo
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- CN103940575B CN103940575B CN201410161003.3A CN201410161003A CN103940575B CN 103940575 B CN103940575 B CN 103940575B CN 201410161003 A CN201410161003 A CN 201410161003A CN 103940575 B CN103940575 B CN 103940575B
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Abstract
A kind of appraisal procedure of wind tunnel test balance based on strain signal energy, its way is mainly, dummy vehicle top inwall, model framework and balance are respectively mounted model, framework, balance three-dimensional foil gauge, that measures three foil gauges each carry out Fourier transformation to strain signal and obtains spectrum signal, and then calculate the energy normalized eigenvalue of six frequency bands in 0～300Hz, distinguish the difference of the energy normalized eigenvalue of computation model, framework strain signal in the same direction, and the difference of the energy normalized eigenvalue of model and balance strain signal in the same direction again；When each to the difference of both strain energy normalization characteristic values all in prescribed limit time, assessment result judges that the test data of balance are credible, otherwise judges insincere.Thus the Mechanical Data of the model measured by balance when ensureing wind tunnel test is accurately, reliably；Test data more accurate, reliable is provided for aerospace flight vehicle.
Description
Technical field
The present invention relates to calibration and the appraisal procedure of aerospace flight vehicle wind tunnel test balance, particularly relate to a kind of based on
The appraisal procedure of the wind tunnel test balance of strain signal energy.
Background technology
In the development process of aerospace flight vehicle, in order to understand aircraft performance, reduce aircraft developing risk and become
This, it will usually carry out wind tunnel model test.The aerodynamic force size that under a variety of experimental conditions aircraft test model is subject to, power
Square measures, and is experimental project most basic in wind tunnel test.Its test philosophy is, fixes a model in the bottom of wind-tunnel and props up
Seat, the fixing end that the upper end of model bearing penetrates in test model with balance threadeds, the measurement end of balance and test model
In model framework threaded；Model framework fixes joint test model further through bolt.During test, it is passed through specific toward wind-tunnel
The air-flow of wind speed, test model is acted on by corresponding flight force and moment, and this flight force and moment is passed by model framework
Pass the balance of bearing upper end, balance the flight force and moment sensing and measuring on six-freedom degree.By balance (being subject to)
The flight force and moment measured is inferred as the flight force and moment that test model is subject to.
Due to flight force and moment from test model to model framework and balance transmit time, test model and model framework
The connecting bolt of connecting bolt, model framework and balance, the flight force and moment of transmission all can be caused and decline by model framework itself
Subtracting and disturb, causing in wind tunnel model test, the test error of flight force and moment is big, and precision is low.Accordingly, it would be desirable to balance school
Just or assessment.
Existing balance calibration technology mostly is on balance calibration equipment, balance is applied normal loading, and gathers balance
Output signal, calculates the output signal of each component of balance and the variation relation of normal loading.This calibration steps cycle length, step
Many, and the static characteristic of balance can only be calibrated, it is impossible to the dynamic characteristic of balance under actual condition is estimated, causes
The accuracy of the Mechanical Data of the wind tunnel test under actual condition and reliability are difficult to determine, it is impossible to evaluate boat accurately, reliably
The performance of empty aerospace craft, can not provide test data accurate, reliable for aerospace flight vehicle.
Summary of the invention
It is an object of the invention to provide the appraisal procedure of a kind of wind tunnel test balance based on strain signal energy, the method
It is capable of the assessment of balance dynamic output characteristic in the aerospace flight vehicle wind tunnel model test under actual condition, makes aviation
The test error of the flight force and moment of aerospace craft wind tunnel model test in allowed limits, the power that wind tunnel experiment is measured
Learn data more accurately, reliably；It is thus possible to performance more accurate, evaluation aerospace flight vehicle reliably, also can be Aero-Space
Aircraft provides test data more accurate, reliable.
By realizing its goal of the invention, the present invention be the technical scheme is that a kind of wind-tunnel based on strain signal energy tries
Testing the appraisal procedure of balance, its step is as follows:
Before A, test, top inwall, model framework and the balance of dummy vehicle are respectively mounted the strain of model three-dimensional
Sheet, framework three-dimensional foil gauge and balance three-dimensional foil gauge, model three-dimensional foil gauge, framework three-dimensional foil gauge and the strain of balance three-dimensional
The signal output part of sheet is all connected with signal condition instrument；Signal condition instrument is connected with computer also by data acquisition equipment；
B, simulation actual condition, carry out wind tunnel test to dummy vehicle；While test, model three-dimensional foil gauge, frame
The strain signal f that frame three-dimensional foil gauge and balance three-dimensional foil gauge will each be measuredpvT () passes through signal condition with sample frequency L
Computer sent into by instrument；Wherein p=1,2,3, represent model three-dimensional foil gauge, framework three-dimensional foil gauge and the strain of balance three-dimensional respectively
The strain signal gathered on sheet, v=X, Y, Z, represent the strain signal that three-dimensional foil gauge collects in the X, Y, Z direction, t respectively
=1,2,3 ..., N, represent strain signal fpvT the sequence number of the sampled point of (), N is total sampling number；
C, computer pass through Fourier transformation by every road strain signal fpvT () is transformed into spectrum signal φpv(ω)；Wherein
ω=1,2 ..., L/2 is frequency Bing Jiangmei road spectrum signal φpv(ω) it is divided into six frequency bands at 0～300Hz frequency band, carries
Take spectrum signal φpv(ω) at the energy normalized eigenvalue r of strain signal of frequency band ii pv, i=1,2 ..., 6, i is frequency band
Sequence number；
Strain signal in D, X by being obtained by model three-dimensional foil gauge, Y, Z-direction is special in the energy normalized of frequency band i
Value indicative ri 1X、ri 1Y、ri 1ZWith the energy normalizing of strain signal at frequency band i in the X obtained by framework three-dimensional foil gauge, Y, Z-direction
Change eigenvalue ri 2X、ri 2Y、ri 2ZBe calculated as follows respectively obtain in X, Y, Z-direction frequency band i model strain with framework strain
Relative difference
In formula | | represent and seek absolute value,
By the strain signal in the X obtained by model three-dimensional foil gauge, Y, Z-direction in the energy normalized feature of frequency band i
Value ri 1X、ri 1Y、ri 1ZWith the energy normalized of strain signal at frequency band i in the X obtained by balance three-dimensional foil gauge, Y, Z-direction
Eigenvalue ri 3X、ri 3Y、ri 3ZIt is calculated as follows the phase obtaining straining at model strain and the balance of frequency band i in X, Y, Z-direction respectively
To difference
If E is X, model at frequency band i strains and the relative difference of framework strain in Y, Z-direction
In maximum strain and the relative difference of balance strain less than model at frequency band i on 5%, and X, Y, Z-directionIn maximum less than 10%, then judge that all of flight force and moment passes through mould from test model
Type framework is delivered to the error of balance in allowed band, and the balance test data of wind tunnel test are credible；Otherwise, it is determined that aerodynamic force
It is delivered to the error of balance beyond allowed band, the balance test number of wind tunnel test from test model by model framework with moment
According to insincere.
Compared with prior art, the invention has the beneficial effects as follows:
One, at test model, the flight force and moment that model framework is subject to it with the strain signal occurred on balance becomes
Linear positive correlation, the strain value that the three-dimensional foil gauge i.e. installed at three is measured and the linear positive correlation of power being each subject to.Cause
This, the difference of the unidirectional strain value that model foil gauge and framework foil gauge are measured reflects flight force and moment from test
Model Transfer is to the decay on model framework and interference；The unidirectional strain value that model foil gauge and balance foil gauge are measured
Difference reflect decay and the interference that flight force and moment is delivered to balance by framework from test model；When both is each
When strain difference is all in prescribed limit, show that all of flight force and moment is delivered to by model framework from test model
The decay of balance and interference are all in allowed band, and assessment result discriminating test data are credible, otherwise assessment discriminating test result
Insincere, need model framework gentle to sky to improve, calibrate.Thus the model measured by balance when ensureing wind tunnel test
Mechanical Data accurately, reliable；Make wind tunnel test can more accurately, evaluate the performance of aerospace flight vehicle reliably, also can be
Aerospace flight vehicle provides test data more accurate, reliable.
Two, the method for the present invention need not sky flat structure and affects the factor of accuracy of balance and carry out strict analysis and build
Mould, it is only necessary to install three three-dimensional foil gauges and subsequent processing device thereof additional, being processed with data by test just can be with rapid evaluation
The measurement accuracy of balance.Equipment simple installation, repeatable utilization, save experimentation cost, shortened the test period, it is easy to extensively
Ground is applied to the detection test of balance performance, and the development to aerospace flight vehicle is respectively provided with important meaning.
Above-mentioned step C is extracted spectrum signal φpv(ω) at the energy normalized eigenvalue of strain signal of frequency band i
ri pvSpecific practice be:
Use energy balane formulaCalculate every road spectrum signal φpv(ω) answering at frequency band i
The ENERGY E of varying signali pv, in formula, ∫ is integration, | |2For absolute value square；It is calculated every road spectrum signal φ againpv(ω)
Energy normalized eigenvalue r at frequency band ii pv,
Using as above method to quantify strain energy and normalized, it calculates simplicity, can also unify simultaneously
The dimension of strain signal, it is simple to investigate the capacity volume variance between the signal of each road；Objectively respond flight force and moment at transmittance process
In decay and interference.
The present invention is described in further detail with detailed description of the invention below in conjunction with the accompanying drawings.
Accompanying drawing explanation
The mounting structure of related device when Fig. 1 is to be estimated wind tunnel test balance by the method for the embodiment of the present invention
Schematic diagram.
In Fig. 1,1b is model bearing, and the direction of arrow is the airflow direction of wind-tunnel.
Detailed description of the invention
Embodiment
Fig. 1 illustrates, a kind of detailed description of the invention of the present invention is, a kind of wind tunnel test balance based on strain signal energy
Appraisal procedure, its step is as follows:
Before A, test, being respectively mounted model three-dimensional on top inwall, model framework 2 and the balance 3 of dummy vehicle 1 should
Become sheet 1a, framework three-dimensional foil gauge 2a and balance three-dimensional foil gauge 3a, model three-dimensional foil gauge 1a, framework three-dimensional foil gauge 2a and
The signal output part of balance three-dimensional foil gauge 3a is all connected with signal condition instrument；Signal condition instrument also by data acquisition equipment with
Computer is connected；
B, simulation actual condition, carry out wind tunnel test to dummy vehicle；While test, model three-dimensional foil gauge 1a,
The strain signal f that framework three-dimensional foil gauge 2a and balance three-dimensional foil gauge 3a will each measurepvT () passes through letter with sample frequency L
Number regulating instrument sends into computer；Wherein p=1,2,3, represent model three-dimensional foil gauge 1a, framework three-dimensional foil gauge 2a and sky respectively
The strain signal gathered on flat three-dimensional foil gauge 3a, v=X, Y, Z, represent that three-dimensional foil gauge collects in the X, Y, Z direction respectively
Strain signal, t=1,2,3 ..., N, represent strain signal fpvT the sequence number of the sampled point of (), N is total sampling number；
C, computer pass through Fourier transformation by every road strain signal fpvT () is transformed into spectrum signal φpv(ω)；Wherein
ω=1,2 ..., L/2 is frequency；Bing Jiangmei road spectrum signal φpv(ω) it is divided into six frequency bands at 0～300Hz frequency band,
Extract spectrum signal φpv(ω) at the energy normalized eigenvalue r of strain signal of frequency band ii pv, i=1,2 ..., 6, i is frequency band
Sequence number；
Strain signal in D, X by being obtained by model three-dimensional foil gauge 1a, Y, Z-direction is in the energy normalized of frequency band i
Eigenvalue ri 1X、ri 1Y、ri 1ZWith the energy of strain signal at frequency band i in the X obtained by framework three-dimensional foil gauge 2a, Y, Z-direction
Normalization characteristic value ri 2X、ri 2Y、ri 2ZBe calculated as follows respectively obtain in X, Y, Z-direction frequency band i model strain with framework should
The relative difference become
In formula | | represent and seek absolute value；
Strain signal in the X obtained by model three-dimensional foil gauge 1a, Y, Z-direction is special in the energy normalized of frequency band i
Value indicative ri 1X、ri 1Y、ri 1ZReturn with energy at the strain signal of frequency band i in the X obtained by balance three-dimensional foil gauge 3a, Y, Z-direction
One changes eigenvalue ri 3X、ri 3Y、ri 3ZBe calculated as follows respectively obtain in X, Y, Z-direction frequency band i model strain with balance strain
Relative difference
If E is X, model at frequency band i strains and the relative difference of framework strain in Y, Z-direction
In maximum strain and the relative difference of balance strain less than model at frequency band i on 10%, and X, Y, Z-directionIn maximum less than 10%, then judge that all of flight force and moment passes through mould from test model
Type framework is delivered to the error of balance in allowed band, and the balance test data of wind tunnel test are credible；Otherwise, it is determined that aerodynamic force
It is delivered to the error of balance beyond allowed band, the balance test number of wind tunnel test from test model by model framework with moment
According to insincere.
Step C of this example is extracted spectrum signal φpv(ω) at the energy normalized eigenvalue of strain signal of frequency band i
ri pvSpecific practice be:
Use energy balane formulaCalculate every road spectrum signal φpv(ω) answering at frequency band i
The ENERGY E of varying signali pv, in formula, ∫ is integration, | |2For absolute value square；It is calculated every road spectrum signal φ againpv(ω)
Energy normalized eigenvalue r at frequency band ii pv,
Three-dimensional foil gauge and signal condition instrument that the present invention uses can be selected for various existing foil gauge and regulating instrument, as answered
Becoming sheet and can be selected for BE120-2CA (11) the three-dimensional foil gauge of industry Electrical Measuring Instrument limited company of Air China, strain regulating instrument can
Selecting Beijing Orient vibration and noise technique institute INV1861A portable strain regulating instrument, data acquisition equipment selects Beijing
The INV3020C signal gathering analysis meter of Dongfa Inst. of Vibration & Noise Technology.
Claims (2)
1. an appraisal procedure for wind tunnel test balance based on strain signal energy, its step is as follows:
Before A, test, the top inwall at dummy vehicle (1) installs model three-dimensional foil gauge (1a), on model framework (2)
Installation frame three-dimensional foil gauge (2a), and at balance (3) upper installation balance three-dimensional foil gauge (3a), model three-dimensional foil gauge
(1a), framework three-dimensional foil gauge (2a) is all connected with signal condition instrument with the signal output part of balance three-dimensional foil gauge (3a)；Letter
Number regulating instrument is connected with computer also by data acquisition equipment；
B, simulation actual condition, carry out wind tunnel test to dummy vehicle；While test, model three-dimensional foil gauge (1a), frame
The strain signal f that frame three-dimensional foil gauge (2a) and balance three-dimensional foil gauge (3a) will each be measuredpvT () passes through with sample frequency L
Computer sent into by signal condition instrument；Wherein p=1,2,3, represent model three-dimensional foil gauge (1a), framework three-dimensional foil gauge respectively
(2a) strain signal that gather upper with balance three-dimensional foil gauge (3a), v=X, Y, Z, represents that three-dimensional foil gauge is in X, Y, Z side respectively
The strain signal upwards collected, t=1,2,3 ..., N, represent strain signal fpvT the sequence number of the sampled point of (), N is for always to adopt
Number of samples；
C, computer pass through Fourier transformation by every road strain signal fpvT () is transformed into spectrum signal φpv(ω)；Wherein ω=1,
2 ..., L/2 is frequency；Bing Jiangmei road spectrum signal φpv(ω) it is divided into six frequency bands at 0～300Hz frequency band, extracts frequency
Spectrum signal φpv(ω) at the energy normalized eigenvalue r of strain signal of frequency band ii pv, i=1,2 ..., 6, i is the sequence of frequency band
Number；
Strain signal in D, the X that will be obtained by model three-dimensional foil gauge (1a), Y, Z-direction is special in the energy normalized of frequency band i
Value indicativeWith the energy of strain signal at frequency band i in the X obtained by framework three-dimensional foil gauge (2a), Y, Z-direction
Normalization characteristic valueBe calculated as follows respectively obtain in X, Y, Z-direction frequency band i model strain with framework should
The relative difference become
In formula | | represent and seek absolute value
Strain signal in the X that will be obtained by model three-dimensional foil gauge (1a), Y, Z-direction is in the energy normalized feature of frequency band i
ValueReturn with energy at the strain signal of frequency band i in the X obtained by balance three-dimensional foil gauge (3a), Y, Z-direction
One changes eigenvalueBe calculated as follows respectively obtain in X, Y, Z-direction frequency band i model strain with balance strain
Relative difference
If E is X, model at frequency band i strains and the relative difference of framework strain in Y, Z-directionIn
The model that big value is less than on 5%, and X, Y, Z-direction at frequency band i strains and the relative difference of balance strain
In maximum less than 10%, then judge that all of flight force and moment is delivered to balance from test model by model framework
Error is in allowed band, and the balance test data of wind tunnel test are credible；Otherwise, it is determined that flight force and moment leads to from test model
Crossing model framework and be delivered to the error of balance beyond allowed band, the balance test data of wind tunnel test are insincere.
The appraisal procedure of a kind of wind tunnel test balance based on strain signal energy the most according to claim 1, its feature
It is: described step C is extracted spectrum signal φpv(ω) at the energy normalized eigenvalue of strain signal of frequency band i's
Specific practice is:
Use energy balane formulaCalculate every road spectrum signal φpv(ω) strain at frequency band i is believed
Number energyIn formula, ∫ is integration, | |2For absolute value square；It is calculated every road spectrum signal φ againpv(ω) at frequency
Energy normalized eigenvalue with i
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| CN106017857B (en) * | 2016-05-26 | 2017-07-11 | 中国人民解放军63820部队吸气式高超声速技术研究中心 | The measuring method of Air-breathing hypersonic vehicle segmented part aerodynamic force |
| CN106126915B (en) * | 2016-06-23 | 2017-03-22 | 中国人民解放军63820部队吸气式高超声速技术研究中心 | Prediction method for vibration signal stable value of wind tunnel balance |
| CN112461494B (en) * | 2020-11-09 | 2022-09-02 | 中国空气动力研究与发展中心 | Pulse combustion wind tunnel model support-balance integrated force measuring device |
| CN116296243B (en) * | 2023-03-03 | 2024-02-23 | 西南交通大学 | Pneumatic identification method based on large-size nuclear dense blocks |
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| CN103674472A (en) * | 2013-12-25 | 2014-03-26 | 中国航空工业集团公司沈阳空气动力研究所 | Automatic three-level weight loading device and loading method for wind tunnel balance calibration |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JP5354660B2 (en) * | 2009-04-08 | 2013-11-27 | 独立行政法人 宇宙航空研究開発機構 | Substation support interference correction method in subsonic half model wind tunnel test |
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| CN1260481A (en) * | 2000-01-19 | 2000-07-19 | 山西省气象局 | Method and device for automatic detection and control of wind tunnel speed |
| CN101968399A (en) * | 2010-10-18 | 2011-02-09 | 西南交通大学 | Wind tunnel testing system for vehicle and bridge models |
| RU2477460C1 (en) * | 2011-07-14 | 2013-03-10 | Российская Федерация, от имени которой выступает Министерство промышленности и торговли Российской Федерации (Минпромторг России) | Method of defining factors of aerodynamic forces and moments at steady-state rotation of aircraft model and device to this end |
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