CN106596034A - Method for judging model testbed rotor wing balance test data validity - Google Patents
Method for judging model testbed rotor wing balance test data validity Download PDFInfo
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- CN106596034A CN106596034A CN201611068400.1A CN201611068400A CN106596034A CN 106596034 A CN106596034 A CN 106596034A CN 201611068400 A CN201611068400 A CN 201611068400A CN 106596034 A CN106596034 A CN 106596034A
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- rotor
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M9/00—Aerodynamic testing; Arrangements in or on wind tunnels
- G01M9/06—Measuring arrangements specially adapted for aerodynamic testing
- G01M9/062—Wind tunnel balances; Holding devices combined with measuring arrangements
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- General Physics & Mathematics (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
- Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)
Abstract
The invention discloses a method for judging model testbed rotor wing balance test data validity. The method for judging model testbed rotor wing balance test data validity includes the following steps: 1. conducting a rotor wing test on a test piece to be tested; 2. obtaining n sets of amplitude-frequency data; 3. solving the fundamental frequency of a rotor wing; 4. obtaining multiple terms of data at testbed rotor wing balance main shaft, and respectively forming correlation arrays; 5. determining a plurality of cross correlation coefficients of the correlation arrays; and 6. judging whether at least two of the plurality of correlation coefficients exceed a threshold value, if yes, model testbed rotor wing balance test data being valid. The method for judging model testbed rotor wing balance test data validity can improve the confidence degree of judging rotor wing performance through a rotor wing balance dynamic load and testbed vibration data fundamental frequency amplitude correlation calculation, and guarantees testbed and test piece safety.
Description
Technical field
The present invention relates to helicopter model Rotor Test technical field, more particularly to a kind of judgment models testing stand rotor
The method of balance test data validity.
Background technology
Rotor balances test data is the test and monitoring parameter that helicopter model rotor hovers and wind tunnel test is important, its
Whether effectively data, are not only related to the Comprehensive Evaluation to rotary wing performance quality, while and ensureing testing stand and testpieces peace
Full key index.
The fundamental frequency of both rotor balances test data and testing stand vibration has close dependency, by its fundamental frequency width
Value relative coefficient is calculated, and the effectiveness of the rotor balances test data that can be obtained to measurement is passed judgment on, and then can be carried
The high confidence level for passing judgment on rotary wing performance quality, and ensure testing stand and testpieces safety.
Current rotor model test only carries out static loading inspection to rotor balances in static state, it is impossible to which rotor is operated
The effectiveness of rotor balances test data during state is passed judgment on.
Thus, it is desirable to have a kind of technical scheme come overcome or at least mitigate prior art at least one drawbacks described above.
The content of the invention
Explanation of nouns：Rotor is always away from the angle referred between rotor blade cross section centrage and horizontal line.
It is an object of the invention to provide a kind of method of judgment models testing stand rotor balances test data effectiveness is come
Overcome or at least mitigate prior art at least one of drawbacks described above.
For achieving the above object, the present invention provides a kind of side of judgment models testing stand rotor balances test data effectiveness
Method, the method for the judgment models testing stand rotor balances test data effectiveness comprise the steps：
Step 1：Rotor Test is carried out to part to be tested；
Step 2：From the test data of the step 1 select rotating speed it is constant, rotor always away from incremental n group test datas,
Each state at least intercepts the data of the scheduled time and carries out fft analysis, so as to obtain n group amplitude-frequency data；
Step 3：According to rotating speed fixed given in the Rotor Test, the fundamental frequency of rotor is asked for；
Step 4：According to the data in the step 2 and the step 3, obtain multinomial at testing stand rotor balances main shaft
Data, and each constitute related array；
Step 5：Multiple cross-correlation coefficients are tried to achieve by the related array in formula and the step 4；
Step 6：Predetermined threshold value, and judge whether at least two cross-correlation coefficients exceed threshold in multiple cross-correlation coefficients
Value, if so, then rig for model test rotor balances test data is effective；If it is not, then rig for model test rotor balances test data without
Effect.
Preferably, the multinomial data include：Hanging down at the course vibration Gx, rotor balances main shaft at rotor balances main shaft
To lateral vibration Gz at vibration Gy and rotor balances main shaft, rotor balances course moment M x, rotor balances vertical bending My, rotation
Wing balance side force Fz and lateral moment M z of rotor balances.
Preferably, the step 3 is specially：According to the test speed rpm of rotor, the fundamental frequency f of rotor is calculated.
Preferably, the computing formula of the fundamental frequency f of calculating rotor is：The unit of f=rpm/60, wherein rpm is：Rev/min,
The unit of f is：Hz.
Preferably, the step 4 is specially：
Course vibration Gx from the corresponding testing stand rotor balances main shaft of n group amplitude-frequency extracting data fundamental frequencies, vertical shake
Dynamic Gy and lateral vibration Gz, (1,2,3 ... n), (1,2,3 ... n) (1,2,3 ... n) with Gz for Gy to separately constitute one-dimension array Gx.
From corresponding rotor balances course moment Ms x of n group amplitude-frequency extracting data fundamental frequency f, vertical bending My, side force Fz
With lateral moment M z, separately constitute one-dimension array Mx (1,2,3 ... n), My (1,2,3 ... n), Fz (1,2,3 ... n) and Mz (1,2,
3…n)。
Preferably, the step 5 is specially：
Using cross-correlation function calculate respectively Gx (1,2,3 ... n) and Mx (1,2,3 ... n), Gy (1,2,3 ... n) and My (1,
2,3 ... n), Gz (1,2,3 ... n) and Fz (1,2,3 ... n), (1,2,3 ... n) (1,2,3 ... cross-correlation coefficient n), obtains Gz with Mz
To corresponding cross-correlation coefficient Rxx, Ryy, Rzz1 and Rzz2.
Preferably, n >=5 in the step 2.
The method of the judgment models testing stand rotor balances test data effectiveness of the application is by rotor balances dynamic load
Lotus and testing stand vibration data fundamental frequency amplitude correlation calculations, the effectiveness of the rotor balances test data that measurement can be obtained
Passed judgment on, and then the confidence level for passing judgment on rotary wing performance quality can be improved, and ensured testing stand and testpieces safety.
Description of the drawings
Fig. 1 is the method for judgment models testing stand rotor balances test data effectiveness according to a first embodiment of the present invention
Schematic flow sheet.
Specific embodiment
To make purpose, technical scheme and the advantage of present invention enforcement clearer, below in conjunction with the embodiment of the present invention
Accompanying drawing, the technical scheme in the embodiment of the present invention is further described in more detail.In the accompanying drawings, identical from start to finish or class
As label represent same or similar element or the element with same or like function.Described embodiment is the present invention
A part of embodiment, rather than the embodiment of whole.It is exemplary below with reference to the embodiment of Description of Drawings, it is intended to use
It is of the invention in explaining, and be not considered as limiting the invention.Based on the embodiment in the present invention, ordinary skill people
The every other embodiment obtained under the premise of creative work is not made by member, belongs to the scope of protection of the invention.Under
Face combines accompanying drawing and embodiments of the invention is described in detail.
In describing the invention, it is to be understood that term " " center ", " longitudinal direction ", " horizontal ", "front", "rear",
The orientation or position relationship of the instruction such as "left", "right", " vertical ", " level ", " top ", " bottom " " interior ", " outward " is based on accompanying drawing institute
The orientation for showing or position relationship, are for only for ease of the description present invention and simplify description, rather than indicate or imply the dress of indication
Put or element with specific orientation, with specific azimuth configuration and operation, therefore it is not intended that must be protected to the present invention
The restriction of scope.
Fig. 1 is the method for judgment models testing stand rotor balances test data effectiveness according to a first embodiment of the present invention
Schematic flow sheet.
The method of the judgment models testing stand rotor balances test data effectiveness as shown in Figure 1 includes following step
Suddenly：
Step 1：Rotor Test is carried out to part to be tested；
Step 2：From the test data of the step 1 select rotating speed it is constant, rotor always away from incremental n group test datas,
Each state at least intercepts the data of the scheduled time and carries out fft analysis, so as to obtain n group amplitude-frequency data；
Step 3：According to rotating speed fixed given in the Rotor Test, the fundamental frequency of rotor is asked for；
Step 4：According to the data in the step 2 and the step 3, obtain multinomial at testing stand rotor balances main shaft
Data, and each constitute related array；
Step 5：Multiple cross-correlation coefficients are tried to achieve by the related array in formula and the step 4；
Step 6：Predetermined threshold value, and judge whether at least two cross-correlation coefficients exceed threshold in multiple cross-correlation coefficients
Value, if so, then rig for model test rotor balances test data is effective；If it is not, then rig for model test rotor balances test data without
Effect.
In the present embodiment, the formula in step 5 is cross-correlation function：
It is understood that the formula is existing skill
Art, will not be described here.
In the present embodiment, the multinomial data include：Course vibration Gx at rotor balances main shaft, rotor balances main shaft
Lateral vibration Gz, rotor balances course moment M x at the vertical vibration Gy and rotor balances main shaft at place, rotor balances are vertical curved
Square My, rotor balances side force Fz and lateral moment M z of rotor balances.
In the present embodiment, the step 3 is specially：According to the test speed rpm of rotor, the fundamental frequency f of rotor is calculated.
In the present embodiment, the computing formula of the fundamental frequency f of calculating rotor is：The unit of f=rpm/60, wherein rpm is：
Rev/min, the unit of f is：Hz.
In the present embodiment, the step 4 is specially：
Course vibration Gx from the corresponding testing stand rotor balances main shaft of n group amplitude-frequency extracting data fundamental frequencies, vertical shake
Dynamic Gy and lateral vibration Gz, (1,2,3 ... n), (1,2,3 ... n) (1,2,3 ... n) with Gz for Gy to separately constitute one-dimension array Gx.
From corresponding rotor balances course moment Ms x of n group amplitude-frequency extracting data fundamental frequency f, vertical bending My, side force Fz
With lateral moment M z, separately constitute one-dimension array Mx (1,2,3 ... n), My (1,2,3 ... n), Fz (1,2,3 ... n) and Mz (1,2,
3…n)。
Preferably, the step 5 is specially：
Using cross-correlation function calculate respectively Gx (1,2,3 ... n) and Mx (1,2,3 ... n), Gy (1,2,3 ... n) and My (1,
2,3 ... n), Gz (1,2,3 ... n) and Fz (1,2,3 ... n), (1,2,3 ... n) (1,2,3 ... cross-correlation coefficient n), obtains Gz with Mz
To corresponding cross-correlation coefficient Rxx, Ryy, Rzz1 and Rzz2.
In the present embodiment, n >=5 in the step 2.
The method of the judgment models testing stand rotor balances test data effectiveness of the application is by rotor balances dynamic load
Lotus and testing stand vibration data fundamental frequency amplitude correlation calculations, the effectiveness of the rotor balances test data that measurement can be obtained
Passed judgment on, and then the confidence level for passing judgment on rotary wing performance quality can be improved, and ensured testing stand and testpieces safety.
By way of example the application is described in detail below.It is understood that this is illustrated do not constitute to this
Any restriction of application.
Example is as follows：
(1) carry out Rotor Test, rotor rotating speed rpm is 1002 revs/min, obtain respectively always away from for 2 °, 3 °, 4 °, 5 °,
6 °, 7 °, 8 °, 9 ° of test data, each state at least intercept 10 second datas and carry out fft analysis and obtain corresponding 8 groups of amplitude-frequency numbers
According to.
(2) according to test speed rpm, fundamental frequency f is calculated, computing formula is：F=rpm/60=1002/60=16.7.
(3) course vibration Gx from the corresponding testing stand rotor balances main shaft of 8 groups of amplitude-frequency extracting data fundamental frequency f, hang down
To vibration Gy and lateral vibration Gz, separately constitute one-dimension array Gx (1,2,3 ... 8), Gy (1,2,3 ... 8) and Gz (1,2,3 ... 8),
Test data see the table below 1.
(4) from corresponding rotor balances course vibration moment M x of 8 groups of amplitude-frequency extracting data fundamental frequency f, vertical bending My, side
To power Fz and lateral moment M z, (1,2,3 ... 8), (1,2,3 ... 8), (1,2,3 ... n) and Mz for Fz for My to separately constitute one-dimension array Mx
(1,2,3 ... 8), and test data see the table below 1.
1 Rotor Test data of table
(5) Gx (1,2,3 ... 8) and Mx (1,2,3 ... 8), Gy (1,2,3 ... 8) and My are calculated respectively using cross-correlation function
(1,2,3 ... n), Gz (1,2,3 ... n) and Fz (1,2,3 ... n), Gz (1,2,3 ... n) and Mz (1,2,3 ... cross-correlation coefficient n),
Corresponding cross-correlation coefficient Rxx, Ryy, Rzz1 and Rzz2 are obtained, cross-correlation coefficient see the table below 2.
2 cross-correlation coefficient of table
| Rxx | Ryy | Rzz1 | Rzz2 |
| 0.8431 | 0.9899 | 0.9904 | 0.9945 |
(6) if numerical value >=0.95 of Rxx, Ryy, Rzz1 and Rzz2 at least 2, can be determined that rotor balances are tested
Whether data are effective.Understand that Ryy, Rzz1 and Rzz2 are more than 0.95 from upper table 2, therefore can determine that this example rotor balances are tested
Data are effective.
It is last it is to be noted that：Above example only to illustrate technical scheme, rather than a limitation.To the greatest extent
Pipe has been described in detail to the present invention with reference to the foregoing embodiments, it will be understood by those within the art that：Which is still
Technical scheme described in foregoing embodiments can be modified, or equivalent is carried out to which part technical characteristic and replace
Change；And these modifications or replacement, do not make the essence of appropriate technical solution depart from the essence of various embodiments of the present invention technical scheme
God and scope.
Claims (7)
1. a kind of method of judgment models testing stand rotor balances test data effectiveness, it is characterised in that the judgment models
The method of testing stand rotor balances test data effectiveness comprises the steps：
Step 1：Rotor Test is carried out to part to be tested；
Step 2：From the test data of the step 1 select rotating speed it is constant, rotor always away from incremental n group test datas, each
State at least intercepts the data of the scheduled time and carries out fft analysis, so as to obtain n group amplitude-frequency data；
Step 3：According to rotating speed fixed given in the Rotor Test, the fundamental frequency of rotor is asked for；
Step 4：According to the data in the step 2 and the step 3, many item numbers at testing stand rotor balances main shaft are obtained
According to, and each constitute related array；
Step 5：Multiple cross-correlation coefficients are tried to achieve by the related array in formula and the step 4；
Step 6：Predetermined threshold value, and judge whether at least two cross-correlation coefficients exceed threshold value in multiple cross-correlation coefficients, if
It is that then rig for model test rotor balances test data is effective；If it is not, then rig for model test rotor balances test data is invalid.
2. the method for judgment models testing stand rotor balances test data effectiveness as claimed in claim 1, it is characterised in that
The multinomial data include：The vertical vibration Gy at course vibration Gx, rotor balances main shaft and rotor at rotor balances main shaft
Lateral vibration Gz, rotor balances course moment M x at balance main shaft, rotor balances vertical bending My, rotor balances side force Fz
With lateral moment M z of rotor balances.
3. the method for judgment models testing stand rotor balances test data effectiveness as claimed in claim 2, it is characterised in that
The step 3 is specially：According to the test speed rpm of rotor, the fundamental frequency f of rotor is calculated.
4. the method for judgment models testing stand rotor balances test data effectiveness as claimed in claim 3, it is characterised in that
The computing formula of fundamental frequency f for calculating rotor is：The unit of f=rpm/60, wherein rpm is：Rev/min, the unit of f is：Hz.
5. the method for judgment models testing stand rotor balances test data effectiveness as claimed in claim 2, it is characterised in that
The step 4 is specially：
Course vibration Gx from the corresponding testing stand rotor balances main shaft of n group amplitude-frequency extracting data fundamental frequencies, vertical vibration Gy
With lateral vibration Gz, (1,2,3 ... n), (1,2,3 ... n) (1,2,3 ... n) with Gz for Gy to separately constitute one-dimension array Gx.
From corresponding rotor balances course moment Ms x of n group amplitude-frequency extracting data fundamental frequency f, vertical bending My, side force Fz and side
To moment M z, (1,2,3 ... n), (1,2,3 ... n), (1,2,3 ... n) and Mz (1,2,3 ... for Fz for My to separately constitute one-dimension array Mx
n)。
6. the method for judgment models testing stand rotor balances test data effectiveness as claimed in claim 5, it is characterised in that
The step 5 is specially：
Gx (1,2,3 ... n) and Mx (1,2,3 ... n), Gy (1,2,3 ... n) and My (1,2,3 ... are calculated respectively using cross-correlation function
N), Gz (1,2,3 ... n) and Fz (1,2,3 ... n), Gz (1,2,3 ... n) and Mz (1,2,3 ... cross-correlation coefficient n) obtains correspondence
Cross-correlation coefficient Rxx, Ryy, Rzz1 and Rzz2.
7. the method for judgment models testing stand rotor balances test data effectiveness as claimed in claim 6, it is characterised in that
N >=5 in the step 2.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108020396A (en) * | 2017-12-29 | 2018-05-11 | 北京航天测控技术有限公司 | A kind of intelligent monitoring device and system suitable for wind-tunnel measurements system |
| CN112697387A (en) * | 2020-12-23 | 2021-04-23 | 中国空气动力研究与发展中心超高速空气动力研究所 | Method for analyzing validity of measurement data of film resistance thermometer in wind tunnel aerodynamic heat test |
| CN113155270A (en) * | 2021-04-28 | 2021-07-23 | 广东天信电力工程检测有限公司 | Vibration sensor data validity online intelligent judgment method |
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| JPH02161331A (en) * | 1988-12-14 | 1990-06-21 | Mitsubishi Electric Corp | Intermittent blowdown type wind tunnel testing device |
| CN202066487U (en) * | 2011-01-10 | 2011-12-07 | 江西昌河航空工业有限公司 | Rotor dynamic balancing testing stand co-taper measuring device |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112697387A (en) * | 2020-12-23 | 2021-04-23 | 中国空气动力研究与发展中心超高速空气动力研究所 | Method for analyzing validity of measurement data of film resistance thermometer in wind tunnel aerodynamic heat test |
| CN113155270A (en) * | 2021-04-28 | 2021-07-23 | 广东天信电力工程检测有限公司 | Vibration sensor data validity online intelligent judgment method |
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