CN106950433A - A kind of low electromagnetic scattering background environment implementation method for adapting to condition of high vacuum degree - Google Patents
A kind of low electromagnetic scattering background environment implementation method for adapting to condition of high vacuum degree Download PDFInfo
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- CN106950433A CN106950433A CN201710104222.1A CN201710104222A CN106950433A CN 106950433 A CN106950433 A CN 106950433A CN 201710104222 A CN201710104222 A CN 201710104222A CN 106950433 A CN106950433 A CN 106950433A
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- groined type
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/08—Measuring electromagnetic field characteristics
- G01R29/0807—Measuring electromagnetic field characteristics characterised by the application
- G01R29/0814—Field measurements related to measuring influence on or from apparatus, components or humans, e.g. in ESD, EMI, EMC, EMP testing, measuring radiation leakage; detecting presence of micro- or radiowave emitters; dosimetry; testing shielding; measurements related to lightning
- G01R29/0821—Field measurements related to measuring influence on or from apparatus, components or humans, e.g. in ESD, EMI, EMC, EMP testing, measuring radiation leakage; detecting presence of micro- or radiowave emitters; dosimetry; testing shielding; measurements related to lightning rooms and test sites therefor, e.g. anechoic chambers, open field sites or TEM cells
Abstract
The invention discloses a kind of low electromagnetic scattering background environment implementation method for adapting to condition of high vacuum degree, low amount of gas evolved absorbing material is fabricated to pyramidal shaped structures first, then processing and fabricating cylinder stainless steel groined type backrest, pyramidal shaped structures are mounted in groined type backrest, inside vacuum tank or vacuum tank is heat sink internal installs guide rail, pulley is installed in stainless steel groined type backrest bottom, by pyramidal shaped structures and stainless steel groined type backrest overall structure by pulley and guideway transport into vacuum tank, form the low electromagnetic scattering background environment for adapting to condition of high vacuum degree.The present invention increases low electromagnetic scattering test function on the basis of vacuum tank is existing, realizes the compound of radar invisible test function and vacuum infrared test function, experimental enviroment condition is provided for the test of exoatmosphere Plasma Stealth.
Description
Technical field
The present invention relates to a kind of low electromagnetic scattering background environment implementation method for adapting to condition of high vacuum degree, belong to plasma hidden
Body technical field of performance test.
Background technology
As a kind of emerging stealth technology, plasma has particularity, i.e. plasma relative to general stealth material
It can be combined, can flow in an atmosphere, the Stealth Fighter of target aircraft is difficult in conventional measurement examination hall for plasma
It is middle to be tested.With environmental concerns closely, general large scale free space plasma needs for plasma generation, maintenance
It could be maintained under relatively low air pressure, thus, plasma properties test, which is generally required, possesses vacuum environment.The opposing party's appearance
Marking Stealth Fighter test needs relatively low electromagnetic scattering background, effectively to obtain the scattering signatures of target.Therefore plasma
The test of body Stealth Fighter needs to carry out under the low electromagnetic scattering background of vacuum.
For exoatmosphere Plasma Stealth performance test, particularly the test of scattering property is, it is necessary in simulation space
Low electromagnetic scattering background is set up in the condition of high vacuum degree environment of environment so that plasma generating equipment can work generation plasma
Body material, and there is provided Stealthy Target and the scattering test environment of plasma in test target region reduction backscatter level.
Performance test generally for space environment target is mainly carried out in vacuum tank, current vacuum tank test system
System mainly has following characteristics, 1) most vacuum tanks are tests for vacuum infrared performance, a small number of vacuum tanks possess plasma
The test function of reflecting properties and transmission performance, but do not possess the low electromagnetic scattering environment of Plasma Stealth performance test；
2) existing vacuum tank absorbing material mainly uses polyurethane foam type absorbing material, and the type absorbing material air content is big, is applicable
In more than 100Pa low-atmospheric pressure test environment, it is impossible to meet the condition of high vacuum degree requirement of the outer vacuum environment of simulated atmosphere layer.
The content of the invention
The technology of the present invention solves problem：Overcoming the deficiencies in the prior art, there is provided a kind of low electricity for adapting to condition of high vacuum degree
Magnetic scattering background environment implementation method, on the basis of vacuum tank is existing, increases low electromagnetic scattering test function, realizes radar invisible
Test function is compound with vacuum infrared test function, and experimental enviroment condition is provided for the test of exoatmosphere Plasma Stealth.
The present invention technical solution be：A kind of low electromagnetic scattering background environment implementation method for adapting to condition of high vacuum degree,
Comprise the following steps：
(1) low amount of gas evolved absorbing material is fabricated to pyramidal shaped structures, the low amount of gas evolved absorbing material is applied to pressure
For 1Pa to standard atmospheric pressure experimental enviroment；
(2) the stainless steel groined type backrest of processing and fabricating cylinder, mounts the angle of step (1) making in groined type backrest
Pyramidal structure, each pyramidal shaped structures close proximity forms the low scattering test zone of cylindrical plasma；
(3) inside vacuum tank or vacuum tank is heat sink internal installs guide rail；
(4) pulley is installed in stainless steel groined type backrest bottom, pyramidal shaped structures and stainless steel groined type backrest are overall
Structure, into vacuum tank, forms the low electromagnetic scattering background environment for adapting to condition of high vacuum degree by pulley and guideway transport.
The method that pyramidal shaped structures are made in the step (1) is as follows：
(2.1) thickness and absorbent of the low amount of gas evolved absorbing material of honeycomb are selected, in the low amount of gas evolved material of honeycomb
Absorbent is soaked on the hole wall of material, the thickness and absorbent of the low amount of gas evolved material of honeycomb ensure the pyramid completed
Shape structure reflectivity is -50dB；
(2.2) in the low amount of gas evolved material surface covering temperature-resistant wet of honeycomb and the macromolecule polyester flat-sheet material of easy cleaning
Material；
(2.3) four isoceles triangles are cut out on the low amount of gas evolved material of honeycomb after step (2.2) processing
Four isosceles triangles are spliced into a pyramidal structure by shape, a height of 30cm-50cm of isosceles triangle.
The integrally-built external diameter of stainless steel groined type backrest is less than vacuum tank internal diameter 3cm-5cm.
Compared with prior art, the present invention has the advantages that：
(1) present invention realizes condition of high vacuum degree environment using vacuum tank, by the way that pyramidal structure is mounted on into stainless steel groined type
In backrest, the low electromagnetic scattering background testing environment of cylinder is formed, and is pushed to groined type backrest with pulley by guide rail
In vacuum tank, formation vacuum tank/heat sink --- groined type background and the low electromagnetic scattering background environment of the vacuum of absorbing material possesses
Normal pressure can form vacuum radar invisible and vacuum to 1Pa condition of high vacuum degree and ambient level -40dB scattering experimental enviroment
Infrared stealth composite test experimental enviroment.
(2) present invention by guide rail and pulley, two kinds of test functions can be realized simultaneously, when need carry out radar invisible experiment
During test, by pyramidal shaped structures and stainless steel groined type backrest overall structure by pulley and guideway transport into vacuum tank, shape
Into the low electromagnetic scattering background environment of vacuum；When needing to carry out the stealthy experiment of vacuum infrared or other vacuum performance experimental tests,
Pyramidal shaped structures and stainless steel groined type backrest overall structure can be pulled out to outside vacuum tank by pulley and guide rail, so as to realize
The switching of radar and infrared composite test environment.
Brief description of the drawings
Fig. 1 is flow chart of the present invention；
Fig. 2 is that pyramidal shaped structures are installed to the schematic diagram after vacuum tank with stainless steel groined type backrest overall structure；
Fig. 3 is pyramidal structure schematic diagram；
Fig. 4 is the low amount of gas evolved material schematic diagram of honeycomb；
Fig. 5 is to transport pyramidal shaped structures and the integrally-built schematic diagram of stainless steel groined type backrest by dolly；
Fig. 6 is the reflectivity performance test curve of pyramid absorbing material sub-assembly.
Embodiment
For the Plasma Stealth performance detection environment of simulated atmosphere layer outer space background, the present invention proposes one kind true
The low electromagnetic scattering background environment implementation method of condition of high vacuum degree is adapted in slack tank, the existing basic condition of vacuum tank can be utilized, newly
Increase low electromagnetic scattering test function, realize the compound of radar invisible test function and vacuum infrared test function, be exoatmosphere
Plasma Stealth test provides experimental enviroment condition, and test wrapper is provided for the RCS attribute testings of aircraft Plasma Stealth
Border implementation method and test site.
As shown in figure 1, the step of the present invention is as follows：
(1) low amount of gas evolved absorbing material is fabricated to pyramidal shaped structures, the low amount of gas evolved absorbing material is applied to pressure
For 1Pa to standard atmospheric pressure experimental enviroment.
The method for making pyramidal shaped structures is as follows：
(2.1) thickness and absorbent of the low amount of gas evolved material of honeycomb are selected, in the low amount of gas evolved material of honeycomb
Absorbent is soaked on hole wall, the thickness and absorbent of the low amount of gas evolved material of honeycomb ensure the pyramid knot completed
Structure reflectivity is -50dB；It is illustrated in figure 4 the low amount of gas evolved material schematic diagram of honeycomb.
(2.2) in the low amount of gas evolved material surface covering temperature-resistant wet of honeycomb and the macromolecule polyester flat-sheet material of easy cleaning
Material；
(2.3) four isoceles triangles are cut out on the low amount of gas evolved material of honeycomb after step (2.2) processing
Four isosceles triangles are spliced into a pyramidal structure by shape, a height of 30cm-50cm of isosceles triangle.
It is illustrated in figure 3 pyramidal structure schematic diagram.
(2) the stainless steel groined type backrest overall structure of processing and fabricating cylinder, stainless steel groined type backrest overall structure
External diameter be less than vacuum tank internal diameter 3cm-5cm.The pyramidal shaped structures of step (1) making, each angle are mounted in groined type backrest
Pyramidal structure close proximity, forms the low scattering test zone of cylindrical plasma.
(3) inside vacuum tank or vacuum tank is heat sink internal installs guide rail.
(4) pulley is installed in stainless steel groined type backrest overall structure bottom, by pyramidal shaped structures and stainless steel groined type
Backrest overall structure, into vacuum tank, forms the low electromagnetic scattering background ring for adapting to condition of high vacuum degree by pulley and guideway transport
Border.It is illustrated in figure 2 pyramidal shaped structures and is installed to the schematic diagram after vacuum tank with stainless steel groined type backrest overall structure.
Further, pyramidal shaped structures and stainless steel groined type backrest overall structure are passed through into pulley and guide rail in order to realize
Transport in vacuum tank, dolly of the present invention design with guide rail, guide rail and the vacuum tank inside of dolly or vacuum tank are heat sink interior
The guide rail spacing in portion is consistent, and pyramidal shaped structures and stainless steel groined type backrest overall structure are placed on into vehicle guide by crane
On, vacuum tank tank door is transported to by dolly.Guide rail on dolly aligns with the guide rail in vacuum tank, is then pushed away in operating personnel
Dynamic lower realize transports overall structure in vacuum tank, while when not needing low electromagnetic scattering environment, operating personnel will be overall
Structure is withdrawn on dolly and transported.It is illustrated in figure 5 and pyramidal shaped structures and stainless steel groined type backrest entirety is transported by dolly
The schematic diagram of structure.
In order to ensure that the guide rail on dolly aligns with the guide rail in vacuum tank, jack is placed in dolly bottom, in dolly
It is machined with slide bar below guide rail, slide bar is used to align on the guide rail on dolly and guide rail in vacuum tank or so, and jack is used for
By the guide rail consistency from top to bottom in the guide rail and vacuum tank on dolly.
The present invention utilizes the low gas content flow characteristic and easy discharge characteristic of cellular structural material, and combines outside absorbent and structure
Shape is designed, and realizes the low exhaust to the high-selenium corn and adaptation high vacuum experimental enviroment of electromagnetic wave energy.It is existing in order to make full use of
Have vacuum tank experimental enviroment condition, can inside vacuum tank or vacuum tank it is heat sink it is internal two guide rails are installed, inhale ripple for supporting
Material and its mounting structure etc..According to the planform and physical dimension of vacuum tank, the stainless steel well word of processing and fabricating cylinder
Shape backrest overall structure, mounts the absorbing material of pyramidal shaped structures in groined type backrest, and the plasma for forming cylinder is low
Scatter test zone.In addition, pulley is installed in the overall structure bottom, for driving pyramid absorbing material and stainless steel groined type
Mobile transport of the backrest overall structure on two guide rails, when needing to carry out radar invisible experimental test, ripple material is inhaled by pyramid
Material and stainless steel groined type backrest overall structure, into vacuum tank, form the low electromagnetic scattering back of the body of vacuum by pulley and guideway transport
Scape environment；When needing to carry out the stealthy experiment of vacuum infrared or during other vacuum performance experimental tests, can by pyramid absorbing material with
Stainless steel groined type backrest overall structure is pulled out to outside vacuum tank by pulley and guide rail, so as to realize radar and infrared compound survey
The vacuum electromagnetic Environment Design scheme of test system.
Embodiment：
From the low amount of gas evolved Electromagnetic Wave Absorbing Plate of honeycomb that thickness is 20mm, surface bonding wave transparent fiberglass protection face
Plate, fiberglass protection face board thickness is 0.5mm, then the low amount of gas evolved Electromagnetic Wave Absorbing Plate of honeycomb is cut and pyramid is assembled into
Shape structure, pyramidal shaped structures are highly 300mm, and the present embodiment is assembled into 500mm × 500mm pyramid by 25 pyramidal shaped structures
Absorbing material sub-assembly.It is illustrated in figure 6 the reflectivity performance test curve of pyramid absorbing material sub-assembly.This kind of pyramid is table
Face monocoque, inside is porous honeycomb, special using the low gas content of cellular porous easy discharge characteristic and monocoque
Property, it is possible to achieve low amount of gas evolved of the absorbing material in vacuum, after tested this kind of pyramidal shaped structures not dry linting, capacity
Small, free from extraneous odour, be easy to cleaning, available for normal pressure --- 1Pa high vacuum environment, while the reflectivity of this kind of pyramidal shaped structures can
Reach -50dB.
This kind of pyramid absorbing material sub-assembly is mounted in stainless steel groined type backrest, the low scattering back of the body of cylinder is formed
Scape test environment, and groined type backrest is pushed in vacuum tank by guide rail and pulley, formation vacuum tank/heat sink --- well word
Shape background and the low electromagnetic scattering background environment of the vacuum of absorbing material, groined type backrest can be installed in vacuum tank, dismantled, real
Two kinds of test functions, i.e. radar invisible and infrared stealth composite test are provided simultaneously with a present vacuum tank.
The content not being described in detail in description of the invention belongs to the known technology of those skilled in the art.
Claims (3)
1. a kind of low electromagnetic scattering background environment implementation method for adapting to condition of high vacuum degree, it is characterised in that comprise the following steps：
(1) low amount of gas evolved absorbing material is fabricated to pyramidal shaped structures, it is 1Pa that the low amount of gas evolved absorbing material, which is applied to pressure,
To the experimental enviroment of standard atmospheric pressure；
(2) the stainless steel groined type backrest of processing and fabricating cylinder, mounts the pyramid of step (1) making in groined type backrest
Structure, each pyramidal shaped structures close proximity forms the low scattering test zone of cylindrical plasma；
(3) inside vacuum tank or vacuum tank is heat sink internal installs guide rail；
(4) pulley is installed in stainless steel groined type backrest bottom, by pyramidal shaped structures and stainless steel groined type backrest overall structure
By pulley and guideway transport into vacuum tank, the low electromagnetic scattering background environment for adapting to condition of high vacuum degree is formed.
2. a kind of low electromagnetic scattering background environment implementation method for adapting to condition of high vacuum degree according to claim 1, its feature
It is：The method that pyramidal shaped structures are made in the step (1) is as follows：
(2.1) thickness and absorbent of the low amount of gas evolved absorbing material of honeycomb are selected, in the low amount of gas evolved material of honeycomb
Absorbent is soaked on hole wall, the thickness and absorbent of the low amount of gas evolved material of honeycomb ensure the pyramid knot completed
Structure reflectivity is -50dB；
(2.2) in the low amount of gas evolved material surface covering temperature-resistant wet of honeycomb and the macromolecule polyester plate material of easy cleaning；
(2.3) four isosceles triangles are cut out on the low amount of gas evolved material of honeycomb after step (2.2) processing, etc.
Four isosceles triangles are spliced into a pyramidal structure by a height of 30cm-50cm of lumbar triangle shape.
3. a kind of low electromagnetic scattering background environment implementation method for adapting to condition of high vacuum degree according to claim 1, its feature
It is：The integrally-built external diameter of stainless steel groined type backrest is less than vacuum tank internal diameter 3cm-5cm.
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| CN113033053A (en) * | 2021-03-26 | 2021-06-25 | 北京理工大学 | Efficient electromagnetic scattering modeling and calculating method for composite target with wave-absorbing honeycomb structure |
| CN114256632A (en) * | 2021-12-24 | 2022-03-29 | 中国人民解放军空军工程大学 | Novel honeycomb wave-absorbing composite structure based on inductively coupled plasma |
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