CN108132303A - A kind of near space vehicle thermal protection structure damage positioning method - Google Patents
A kind of near space vehicle thermal protection structure damage positioning method Download PDFInfo
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- CN108132303A CN108132303A CN201711214193.0A CN201711214193A CN108132303A CN 108132303 A CN108132303 A CN 108132303A CN 201711214193 A CN201711214193 A CN 201711214193A CN 108132303 A CN108132303 A CN 108132303A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/14—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object using acoustic emission techniques
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/44—Processing the detected response signal, e.g. electronic circuits specially adapted therefor
- G01N29/46—Processing the detected response signal, e.g. electronic circuits specially adapted therefor by spectral analysis, e.g. Fourier analysis or wavelet analysis
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
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- G01N2291/02—Indexing codes associated with the analysed material
- G01N2291/023—Solids
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/02—Indexing codes associated with the analysed material
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Abstract
The invention discloses a kind of acoustic emission source locating method, wherein, including：Disconnected lead loss, which is picked up, using acoustic emission sensor hinders acoustic emission signal；Direct wave is chosen in acoustic emission signal；Time-domain operation is carried out to the direct wave in acoustic emission signal；Frequency-domain operations are carried out to performing the direct wave after time-domain operates；Displacement fields map function is carried out to the direct wave after execution frequency-domain operations, signal is mapped to the wave-number domain of signal by frequency domain；Displacement space is mapped to the signal of the direct wave after execution displacement fields map function；To being mapped to the signal extraction peak peak amplitude of displacement space and the length of wave packet, to obtain the length of peak peak amplitude and Bo Bao with the changing rule of phase drift；According to changing rule, judge whether when peak peak amplitude reaches maximum value, the length of wave packet is minimum；Translation numerical value in final time shaft dimension is length of the acoustic emission source apart from acoustic emission sensor, to determine the position of acoustic emission source.
Description
Technical field
The invention belongs near space vehicle thermal protection structure damage monitoring technical fields, and in particular to one kind closes on sky
Between aircraft thermal protection structure damage positioning method.
Background technology
Near space vehicle is the course of new aircraft that a kind of Aeronautics and Astronautics technology is combined closely, and is world today sky day
The main study subject in integrated field, with fast reaction, strong prominent anti-, strong destruction and high maneuver warfare and precision strike etc.
Ability has been considered as the strategic high ground safeguarded national security with development interests by American and Britain, Fa Deng developed countries.Near space
Aircraft high-speed flight will bear harsh aerothermal load during reentering, in order to ensure the component energy of aircraft interior
Enough normal works, need an effective thermal protection structure.With being continuously increased for flight Mach number and endurance, fuselage surface temperature
Degree constantly raising, traditional thermal protection structure and material such as metal thermal protection, heat insulation felt etc. can not continue to meet requirement, must
It must be using temperature tolerance higher, the superior ceramic matric composite thermal protection structure of inoxidizability.Due to ceramic matric composite
Combine the spy of long fiber-reinforcing material (being typically carbon fiber or SiC fibers) and refractory ceramic matrix (being typically carbon or SiC)
Property, compared with metal thermal protection structure, have many advantages, such as that heatproof is high, structure is light, bearing capacity is strong, near space vehicle
It is applied in thermal protection structure, such as fibre reinforced SiC ceramic based composites piecemeal (i.e. C/SiC) has been successfully applied to
The surface of the thermal protection structure of multiple spacecrafts such as X-37, X-43A.
The basis material (such as SiC ceramic) of ceramic matric composite has very high brittleness, in addition to generating new fracture
Other than the required surface energy in surface, almost without other energy absorbing mechanisms.Under extraneous load effect, small surface
Scar (scuffing or gap) or internal flaw (micro-crack, hole or field trash) may all cause sudden destruction.2003
U.S.'s shuttle Columbia accident accident, precisely due in return stage, the tiles on external fuel cabin is heat-insulated compound
Material structure comes off under extraneous load excitation, and hitting thermal protection structure causes to damage, and causes space shuttle in return course
Middle explosion is disintegrated.Fig. 2 is C/SiC plates that NASA ground accident reproduction experiments obtain due to damage results caused by high-speed impact.
Therefore, it is necessary to its initial damage position is detected and is accurately positioned before the work of ceramic base thermal protection structure, so as to timely
Damage unit is replaced, so as to ensure the safety of thermal protection structure or even entire aircraft.
Damage check is carried out near space vehicle thermal protection structure using suitable lossless detection method will be to ensureing
The flight safety of near space vehicle plays very crucial effect.NASA is in its advanced Ceramic Matrix Composites Fabricated structural research
In the works, advanced Study on nondestructive detection method considerable position has been placed on.The method of non-destructive testing at present mainly includes
Ultrasound detection, X-ray detection, Computer tomography, infrared detection technology etc..These lossless detection methods have its it is unique should
With field, but there are limitations in thermal protection structure damage monitoring：Such as be difficult to realize whole monitoring in real time, can not be in structure
Orientated damage while damage is only used for small size damage check etc..Correlative study shows C/SiC composite materials
Damage can lead to strong sound emission (Acoustic Emission, referred to as " AE ") characteristic, contain inside acoustic emission signal
About the important information of structural damage, such as damage position, type of impairment and degree of injury etc..In numerous non-destructive testing technologies
In, acoustic emission can be based on from the damage information of itself, position, generation and the expansion of real-time online evaluation structure internal injury
Exhibition process has larger in the engineering practices such as damage identifing source and positioning, crack initiation and propagation monitoring in composite material
Advantage has obtained good application in the detection of C/SiC composite materials.But at present using traditional acoustic emission to knot
The precision that structure damage is positioned is relatively low, seriously constrains it near space vehicle C/SiC thermal protection structure damage reason locations
In application.The Modal Acoustic Emission that developed recently gets up is at a kind of combination Lamb wave theory and the acoustic emission signal of waveform analysis
Reason technology overcomes many deficiencies of traditional parameters acoustic emission detection, is damaged near space vehicle C/SiC thermal protection structures
It has a good application prospect in detection.The basis of Modal Acoustic Emission technology application needs to obtain acoustic emission wave in the medium in advance
Propagation characteristic.However, C/SiC composite materials have anisotropic feature, and there are linkage interfaces so that C/SiC is multiple
Acoustic emission wave propagation characteristic complexity, rule in condensation material thermal protection structure is unknown, it is difficult to realize accurate Modal Acoustic Emission damage
Wound positioning.
Invention content
The purpose of the present invention is to provide a kind of near space vehicle thermal protection structure damage positioning method, for solving
Above-mentioned problem of the prior art.
A kind of acoustic emission source locating method of the present invention, wherein, including：(1) localization region is selected, is arranged in localization region
Acoustic emission sensor；(2) source of damage inside model configuration；(3) it picks up disconnected lead loss using acoustic emission sensor and hinders sound emission letter
Number；(4) direct wave is chosen in acoustic emission signal；(5) time-domain operation is carried out to the direct wave in acoustic emission signal；(6) it is right
The direct wave progress frequency-domain operations after time-domain operation are performed, obtain the frequency domain distribution of signal；(7) to perform frequency-domain operations it
Direct wave afterwards carries out displacement fields map function, and signal is mapped to the wave-number domain of signal by frequency domain；(8) become to performing displacement fields
The signal of the direct wave changed after operating is mapped to displacement space；(9) to being mapped to the signal extraction peak peak amplitude of displacement space
And the length of wave packet, to obtain the length of peak peak amplitude and Bo Bao with the changing rule of phase drift；(10) it is advised according to variation
Rule, judges whether when peak peak amplitude reaches maximum value, and the length of wave packet is minimum,；If it has, then step (11) is performed, if
It is no, then return to step (5), until result is yes；(11) the translation numerical value in final time shaft dimension is acoustic emission source distance
The length of acoustic emission sensor, to determine the position of acoustic emission source.
One embodiment of acoustic emission source locating method according to the present invention, wherein, by being resolved in localization region
Source of damage inside lead test model configuration.
One embodiment of acoustic emission source locating method according to the present invention, wherein, the time-domain operation refers to believe original
Number time domain waveform carries out the translation in time shaft dimension.
One embodiment of acoustic emission source locating method according to the present invention, wherein, direct wave carries out frequency-domain operations use
It is operated for Fast Fourier Transform (FFT).
One embodiment of acoustic emission source locating method according to the present invention, wherein, after execution displacement fields map function
Direct wave carry out inversefouriertransform operation, direct-path signal is mapped to displacement space.
Near space vehicle thermal protection structure damage positioning method of the present invention, it is contemplated that the influence of linkage interface, such as
What carries out the identification of interfacial effect characteristic, carries out the compensation of the propagation effects factors such as frequency dispersion, and development considers what interfacial effect influenced
Acoustic emission source isolation and localization method etc., will provide effective solution and technical method, be remarkably improved at present
Modal Acoustic Emission technology positioning accuracy and reliability in composite structure have apparent characteristic and novelty.
Description of the drawings
Fig. 1 show localization region and divides schematic diagram；
Fig. 2 show the flow chart of near space vehicle thermal protection structure damage positioning method；
Fig. 3 show peak peak amplitude and the length of Bo Bao changes over time rule schematic diagram；
Fig. 4 show acoustic emission signal and is mapped to the signal graph of displacement space.
Specific embodiment
To make the purpose of the present invention, content and advantage clearer, with reference to the accompanying drawings and examples, to the present invention's
Specific embodiment is described in further detail.
Fig. 1 show localization region and divides schematic diagram, and Fig. 2 show near space vehicle thermal protection structure damage reason location
The flow chart of method, Fig. 3 show peak peak amplitude and the length of Bo Bao changes over time rule schematic diagram, and Fig. 4 show sound hair
It penetrates signal and is mapped to the signal graph of displacement space, as shown in Figures 1 to 4, near space vehicle surface segments arrangement
In C/SiC composite material thermal protection structures, if linkage interface of the damage position between adjacent panels, due to position error
In the presence of, then may will damage accidentally positioning to other adjacent plates.This, which may really to damage, to be effectively treated, so as to
Bring serious security risk.For example, illustrate in the sound emission isolation there are linkage interface as shown in Figure 1 with positioning
In figure, when acoustic emission source AE1 is appeared near the interface of P1 plates and P2 plates, the damage position that is positioned by sensor S
P2 plates may be deviated to by P1 by putting, so as to cause erroneous judgement.
The present invention proposes a kind of acoustic emission source locating method, and as shown in Figures 1 to 4, particular content is as follows：
(1) localization region is selected, acoustic emission sensor is arranged in localization region；
(2) carry out resolving lead test in localization region, the source of damage inside model configuration；
(3) it picks up disconnected lead loss using acoustic emission sensor and hinders acoustic emission signal, and store, record；
(4) direct wave, i.e. S0 waves are chosen in acoustic emission signal；
(5) time-domain operation, numerical value a are carried out to the S0 waves in acoustic emission signal；The time-domain operation, refers to original
Time domain plethysmographic signal carries out the translation in time shaft dimension；
(6) frequency-domain operations being carried out to performing the S0 waves after time-domain operates, i.e. Fast Fourier Transform (FFT) (FFT) operates,
Obtain the frequency domain distribution of signal；
(7) displacement fields map function is carried out to the S0 waves after execution frequency-domain operations, signal is mapped to signal by frequency domain
Wave-number domain；
(8) it carries out inversefouriertransform (FFT) to the S0 waves after execution displacement fields map function to operate, signal is mapped
To displacement space；
(9) to being mapped to the corresponding peak peak amplitude of signal extraction of displacement space, the length of wave packet, obtain peak peak amplitude,
The length of wave packet with phase drift changing rule；
(10) according to changing rule judge whether to meet " when peak, it is minimum to reach maximum value, the length of wave packet for peak amplitude " this
Condition；If satisfied, then needing not continue to carry out time-domain operation, if not satisfied, then needing to continue time-domain operation, go forward side by side
Subsequent Fast Fourier Transform (FFT) (FFT) operation of row, until meeting " it is minimum to reach maximum value, the length of wave packet for peak amplitude when peak "
This condition；
(11) the translation numerical value in final time shaft dimension is length of the acoustic emission source apart from acoustic emission sensor, i.e.,
It can determine the position of acoustic emission source.
Although reference example implementation describes the present invention, but it is to be understood that the present invention is not limited to described examples
Property implement or structure.On the contrary, the present invention is directed to include different modifications and equivalent configuration.In addition, though exemplary embodiment
Various elements shown with illustrative various combination and configuration, but including more, less or other groups of single element
It closes and is configured also in the spirit and scope of the present invention.
Near space vehicle thermal protection structure damage positioning method of the present invention proposes to damage in C/SiC composite structures
Hinder the frequency dispersion compensation method of acoustic emission wave, eliminate the Dispersion of acoustic emission signal；Then the signal processing methods pair such as EMD are utilized
The mode of acoustic emission wave is identified, and whether extraction crosses the feature at interface；For the situation for not crossing interface, in the base of dispersion compensation
Damage position is positioned using time reversal method and principle of stacking on plinth；The situation at interface is crossed for acoustic emission wave,
On the basis of obtaining interfacial effect characteristic, m- range conversion when being utilized with reference to frequency dispersion compensation method damage is accurately isolated and fixed
In position to practical damage plate, so as to the sound hair damaged in the C/SiC composite structures in the case of being formed there are linkage interface
Penetrate source isolation and localization method.
Near space vehicle thermal protection structure damage positioning method of the present invention, there are the C/ in the case of linkage interface for foundation
The acoustic emission source isolation damaged in SiC ceramic matrix composite material structure and localization method, this C/SiC that will be promoted near space vehicle
The security reliability of composite material thermal protection structure further pushes acoustic emission to be applied to structural damage detection field.
Near space vehicle thermal protection structure damage positioning method of the present invention, it is contemplated that the influence of linkage interface, such as
What carries out the identification of interfacial effect characteristic, carries out the compensation of the propagation effects factors such as frequency dispersion, and development considers what interfacial effect influenced
Acoustic emission source isolation and localization method etc., will provide effective solution and technical method, be remarkably improved at present
Modal Acoustic Emission technology positioning accuracy and reliability in composite structure have apparent characteristic and novelty.
The above is only the preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art
For member, without departing from the technical principles of the invention, several improvement and deformation can also be made, these are improved and deformation
Also it should be regarded as protection scope of the present invention.
Claims (5)
1. a kind of acoustic emission source locating method, which is characterized in that including：
(1) localization region is selected, acoustic emission sensor is arranged in localization region；
(2) source of damage inside model configuration；
(3) it picks up disconnected lead loss using acoustic emission sensor and hinders acoustic emission signal；
(4) direct wave is chosen in acoustic emission signal；
(5) time-domain operation is carried out to the direct wave in acoustic emission signal；
(6) frequency-domain operations are carried out to performing the direct wave after time-domain operates, obtains the frequency domain distribution of signal；
(7) displacement fields map function is carried out to the direct wave after execution frequency-domain operations, signal is mapped to signal by frequency domain
Wave-number domain；
(8) displacement space is mapped to the signal of the direct wave after execution displacement fields map function；
(9) to being mapped to the signal extraction peak peak amplitude of displacement space and the length of wave packet, to obtain peak peak amplitude and Bo Bao
Length with phase drift changing rule；
(10) according to changing rule, judge whether when peak peak amplitude reaches maximum value, the length of wave packet is minimum；If it has, then
Step (11) is performed, if it has not, then return to step (5), until result is yes；
(11) the translation numerical value in final time shaft dimension is length of the acoustic emission source apart from acoustic emission sensor, to determine sound
The position of emission source.
2. acoustic emission source locating method as described in claim 1, which is characterized in that resolve lead by being carried out in localization region
The source of damage of test simulation inside configuration.
3. acoustic emission source locating method as described in claim 1, which is characterized in that the time-domain operation refers to believe original
Number time domain waveform carries out the translation in time shaft dimension.
4. acoustic emission source locating method as described in claim 1, which is characterized in that direct wave progress frequency-domain operations, which use, is
Fast Fourier Transform (FFT) operates.
5. acoustic emission source locating method as described in claim 1, which is characterized in that after execution displacement fields map function
Direct wave carries out inversefouriertransform operation, and direct-path signal is mapped to displacement space.
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| CN201711214193.0A CN108132303A (en) | 2017-11-28 | 2017-11-28 | A kind of near space vehicle thermal protection structure damage positioning method |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111812210A (en) * | 2020-07-08 | 2020-10-23 | 丁刚 | Method and device for positioning damage source of three-dimensional braided composite material |
| CN113884573A (en) * | 2021-09-02 | 2022-01-04 | 北京强度环境研究所 | Method for identifying fault sound source position of movement mechanism |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111812210A (en) * | 2020-07-08 | 2020-10-23 | 丁刚 | Method and device for positioning damage source of three-dimensional braided composite material |
| CN111812210B (en) * | 2020-07-08 | 2023-04-18 | 丁刚 | Method and device for positioning damage source of three-dimensional braided composite material |
| CN113884573A (en) * | 2021-09-02 | 2022-01-04 | 北京强度环境研究所 | Method for identifying fault sound source position of movement mechanism |
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