CN110220970A - A kind of eddy current sensor method of evaluating performance based on vortex Energy distribution - Google Patents
A kind of eddy current sensor method of evaluating performance based on vortex Energy distribution Download PDFInfo
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- CN110220970A CN110220970A CN201910424909.2A CN201910424909A CN110220970A CN 110220970 A CN110220970 A CN 110220970A CN 201910424909 A CN201910424909 A CN 201910424909A CN 110220970 A CN110220970 A CN 110220970A
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- 238000011156 evaluation Methods 0.000 claims abstract description 9
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- 230000003993 interaction Effects 0.000 claims description 9
- 238000011835 investigation Methods 0.000 claims description 7
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- G01N27/72—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
- G01N27/82—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws
- G01N27/90—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws using eddy currents
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/72—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
- G01N27/82—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws
- G01N27/90—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws using eddy currents
- G01N27/9006—Details, e.g. in the structure or functioning of sensors
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Abstract
The present invention provides a kind of eddy current sensor method of evaluating performance based on vortex Energy distribution, it will set and investigate region division as multiple annular sections, then the corresponding vortex radial energy Distribution Value of each annular section is obtained according to the vortex energy of each annular section, each vortex radial energy Distribution Value is finally substituted into shannon entropy formula, the comentropy based on vortex radial energy distribution is obtained, the intensity that Eddy Distribution in region is investigated in setting is finally evaluated according to comentropy；It can be seen that the comentropy proposed by the present invention based on vortex radial energy distribution can investigate the evaluation index of the distribution intensity in region as vortex in setting, while also as a kind of quantitative optimization index of eddy current sensor.
Description
Technical field
The invention belongs to technical field of nondestructive testing more particularly to a kind of eddy current sensors based on vortex Energy distribution
It can evaluation method.
Background technique
Flexible flat eddy current sensor is a kind of novel plane cylinder sensor, and relative dimensional eddy current sensor is flexible
Plane cylinder sensor has high sensitivity to the detection with the complex surfaces such as curved surface metal component surface, near surface crackle,
The advantages such as anti-lift-off noiseproof feature is strong.But due to flexible flat eddy current sensor, especially manufacture on a printed circuit board
Sensor, coil turn is less, and the arrangement of the shape of excitation coil and pickup unit is to the shadow of sensor performance
It rings very big.Plane cylinder sensor is directly related with the interaction between crackle and vortex to the detection performance of crackle, and whirlpool
The distribution of stream directly decides its probability and power with crack interaction.Therefore, in the design of plane cylinder sensor,
Seem particularly important to the quantitative assessment for the Eddy Distribution result that emulation or numerical value are calculated.However, in the prior art, not
There is a kind of suitable method to evaluate vortex Energy distribution intensity.
Summary of the invention
To solve the above problems, the present invention provides a kind of eddy current sensor performance evaluation side based on vortex Energy distribution
Method can evaluate the intensity that Eddy Distribution in region is investigated in setting, provide reference for the optimization design of eddy current sensor.
A kind of eddy current sensor method of evaluating performance based on vortex Energy distribution, is placed in test specimen to be measured for eddy current sensor
Top, the evaluation method the following steps are included:
S1: investigating in region in setting, will set outward from eddy current sensor center and investigates region division as two or more
Annular section, wherein each annular section adjoins each other；
S2: the vortex energy of each annular section is obtained；
S3: respectively by the vortex energy of each annular section divided by the vortex energy summation of all annular sections, by gained quotient
Value is respectively as the corresponding vortex radial energy Distribution Value of each annular section；
S4: the corresponding vortex radial energy Distribution Value of each annular section is substituted into shannon entropy formula, is obtained based on whirlpool
Comentropy of the flow path to Energy distribution, wherein the comentropy is used to evaluate the vortex Energy distribution collection in setting investigation region
Middle degree；Wherein, the comentropy is smaller, and what each vortex energy in representative setting investigation region was more concentrated is distributed in certain rings
Shape region, the interaction between eddy current sensor and the annular section is stronger, and the comentropy is bigger, represents setting and investigates area
Each eddy current phasor in domain is more evenly distributed in each annular section, the interaction between eddy current sensor and the annular section
It is weaker.
Further, described set investigates region as the surface of test specimen to be measured or is parallel to the flat of surface of test piece to be measured
Face.
Further, the acquisition methods of the vortex energy of each annular section specifically:
The eddy current amplitude square in each annular section is integrated respectively, gained integral result is the whirlpool of each annular section
Stream energy.
Further, the acquisition methods of the vortex energy of each annular section specifically:
Region is investigated into setting and carries out grid dividing, then the vertex of each grid is as sampled point；
The corresponding eddy current amplitude square of sampled point that each annular section includes is summed respectively, gained and value are each ring
The vortex energy in shape region.
Further, the width of each annular section is equal.
Further, each annular section is back-shaped ring or annulus.
The utility model has the advantages that
The present invention provides a kind of eddy current sensor method of evaluating performance based on vortex Energy distribution, and region is investigated in setting
Multiple annular sections are divided into, the radial energy of the corresponding vortex of each annular section is then obtained according to the vortex energy of each annular section
Distribution Value is measured, each vortex radial energy Distribution Value is finally substituted into shannon entropy formula, is obtained based on vortex radial energy point
The comentropy of cloth finally evaluates the intensity that Eddy Distribution in region is investigated in setting according to comentropy；It can be seen that this hair
The comentropy based on vortex radial energy distribution of bright proposition can investigate the distribution collection intermediate range in region in setting as vortex
The evaluation index of degree, and then the power to interact between eddy current sensor and crackle test specimen to be measured is obtained, be conducive to improve and split
The accuracy of line detection, is particularly suitable for the design and selection of excitation coil in flexible flat eddy current sensor, is currents sensing
A kind of quantitative optimization index of device.
Detailed description of the invention
Fig. 1 is a kind of process of eddy current sensor method of evaluating performance based on vortex Energy distribution provided by the invention
Figure；
Fig. 2 is that region division schematic diagram is investigated in setting provided by the invention；
Fig. 3 is that the schematic diagram that region is divided at equal intervals is investigated in setting provided by the invention.
Specific embodiment
In order to make those skilled in the art more fully understand application scheme, below in conjunction in the embodiment of the present application
Attached drawing, the technical scheme in the embodiment of the application is clearly and completely described.
As the EDDY CURRENT of one of the big common detection methods of non-destructive testing five, on the surface of the metal member, near surface splits
Vital positioning is occupied in the detection of line.But with the heteromorphosis that structural design of fittings manufactures, the complexity of surface shape
Change, such as aircraft engine blade, gear etc..This makes traditional eddy current sensor keep permanent with design of part when detecting crackle
Fixed lift off become problem, therefore, can with tested component surface deform flexible flat eddy current sensor use and
It is raw.
Coil turn is a notable feature of planar flexible eddy current sensor less, this makes such sensor several in coil
Very high, such as round, rectangle and its screw structure are required in the selection and design of what feature.Wherein, planar flexible currents sensing
The Eddy Distribution situation that all kinds of excitation coils of device induce in tested component directly decides vortex and crack interaction
Probability and intensity, and it is stronger to interact, the accuracy of crack detection is higher.Therefore, it is necessary to take certain mode, Lai Dingliang
The rule of evaluation vortex Energy distribution.
Referring to Fig. 1, which is a kind of eddy current sensor performance evaluation side based on vortex Energy distribution provided by the embodiment
The flow chart of method.A kind of eddy current sensor method of evaluating performance based on vortex Energy distribution, is placed in crackle for eddy current sensor
The top of test specimen to be measured, the evaluation method the following steps are included:
S1: investigating in region in setting, will set outward from eddy current sensor center and investigates region division as two or more
Annular section, wherein each annular section adjoins each other.
Optionally, the concrete shape of the present embodiment annular section, can be similar to the shape of eddy current sensor excitation coil,
It can be for rectangle, round or ellipse etc.；For example, with reference to Fig. 2, which is that region division is investigated in setting provided in this embodiment
Schematic diagram.As shown in Figure 2, it is a square that region is investigated in the setting of the present embodiment, then excitation coil is the whirlpool of square coil
The detection in region is investigated in the setting that flow sensor is more suitable for square；At this point, with the friendship of two central axis of square coil
That is, centered on the center of square coil, it is wide as 6 will to set investigation region division along the radial direction of square coil outward for point
The square annular region spent and adjoined each other, wherein the square positioned at bosom is regarded as the annular section that internal diameter is 0.
Optionally, according to actual needs, the width of each annular section can also be different.
Region is investigated as the surface of crackle test specimen to be measured or is parallel to crackle test specimen table to be measured it should be noted that setting
The plane in face.
S2: the vortex energy of each annular section is obtained.
Two kinds of acquisition modes of the vortex energy of annular section are described below.
The first: respectively integrating the eddy current amplitude square in each annular section, and gained integral result is each ring-type
The vortex energy in region.
Second: region is investigated into setting and carries out grid dividing, then the vertex of each grid is as sampled point；Then respectively will
The corresponding eddy current amplitude square of the sampled point that each annular section includes is summed, and gained and value are the vortex energy of each annular section
Amount.
It should be noted that since each annular section is radially dividing along eddy current sensor, then each annular section institute
Corresponding diameter is different, and the width of each annular section is also not necessarily equal, and therefore, the area of each annular section is not
With, then it sets and investigates after region marks off multiple sample points at equal intervals, the sample point number that each annular section includes is not
With, that is, drop into the sample point number difference of each annular section.
For example, with reference to Fig. 3, which is that the schematic diagram that region is divided at equal intervals is investigated in setting provided in this embodiment.
Region is investigated in rectangular setting shown in Fig. 2 to be divided at equal intervals, it is clear that the ring-shaped area of outermost annular section and inner layer
The area in domain is different, and the sample point quantity respectively contained is also different therewith.
S3: respectively by the vortex energy of each annular section divided by the vortex energy summation of all annular sections, by gained quotient
Value is respectively as the corresponding vortex radial energy Distribution Value of each annular section.
S4: the corresponding vortex radial energy Distribution Value of each annular section is substituted into shannon entropy formula, is obtained based on whirlpool
Comentropy of the flow path to Energy distribution, wherein the comentropy is used to evaluate the vortex Energy distribution collection in setting investigation region
Middle degree.
Wherein, the comentropy is smaller, and what each vortex energy in representative setting investigation region was more concentrated is distributed in certain
Annular section, the interaction between eddy current sensor and the annular section is stronger, and the comentropy is bigger, represents setting and investigates
Each eddy current phasor in region is more evenly distributed in each annular section, the phase interaction between eddy current sensor and the annular section
With weaker.
Specifically, the calculation formula of comentropy H is as follows:
Wherein, p (i) is the corresponding vortex radial energy Distribution Value of i-th of annular section, and m is the number of annular section,
Log is logarithmic function, and the bottom of logarithmic function is 2 in present embodiment.Therefore the unit of H is dB, which is known as being vortexed radial
The comentropy of Energy distribution.
Certainly, the invention may also have other embodiments, without deviating from the spirit and substance of the present invention, ripe
Various corresponding changes and modifications can be made according to the present invention certainly by knowing those skilled in the art, but these it is corresponding change and
Deformation all should fall within the scope of protection of the appended claims of the present invention.
Claims (6)
1. a kind of eddy current sensor method of evaluating performance based on vortex Energy distribution, is placed in test specimen to be measured for eddy current sensor
Top, which is characterized in that the evaluation method the following steps are included:
S1: investigating in region in setting, will set outward from eddy current sensor center and investigates region division as more than two rings
Shape region, wherein each annular section adjoins each other；
S2: the vortex energy of each annular section is obtained；
S3: respectively by the vortex energy of each annular section divided by the vortex energy summation of all annular sections, by gained quotient point
It Zuo Wei not the corresponding vortex radial energy Distribution Value of each annular section；
S4: the corresponding vortex radial energy Distribution Value of each annular section is substituted into shannon entropy formula, is obtained based on vortex diameter
To the comentropy of Energy distribution, wherein the comentropy is used to evaluate the vortex Energy distribution collection intermediate range in setting investigation region
Degree；Wherein, the comentropy is smaller, and what each vortex energy in representative setting investigation region was more concentrated is distributed in certain ring-shaped areas
Domain, the interaction between eddy current sensor and the annular section is stronger, and the comentropy is bigger, represents setting and investigates in region
Each eddy current phasor be more evenly distributed in each annular section, the interaction between eddy current sensor and the annular section is got over
It is weak.
2. a kind of eddy current sensor method of evaluating performance based on vortex Energy distribution as described in claim 1, feature exist
In described set investigates region as the surface of test specimen to be measured or be parallel to the plane of surface of test piece to be measured.
3. a kind of eddy current sensor method of evaluating performance based on vortex Energy distribution as described in claim 1, feature exist
In the acquisition methods of the vortex energy of each annular section specifically:
The eddy current amplitude square in each annular section is integrated respectively, gained integral result is the vortex energy of each annular section
Amount.
4. a kind of eddy current sensor method of evaluating performance based on vortex Energy distribution as described in claim 1, feature exist
In the acquisition methods of the vortex energy of each annular section specifically:
Region is investigated into setting and carries out grid dividing, then the vertex of each grid is as sampled point；
The corresponding eddy current amplitude square of sampled point that each annular section includes is summed respectively, gained and value are each ring-shaped area
The vortex energy in domain.
5. a kind of eddy current sensor method of evaluating performance based on vortex Energy distribution as described in claim 1, feature exist
In the width of each annular section is equal.
6. a kind of eddy current sensor method of evaluating performance based on vortex Energy distribution as described in claim 1, feature exist
In each annular section is back-shaped ring or annulus.
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| CN112268950A (en) * | 2020-08-31 | 2021-01-26 | 北京工业大学 | Double-layer magnetic shielding type rectangular eddy current sensor |
| CN112557498A (en) * | 2020-11-27 | 2021-03-26 | 兰州理工大学 | Method and device for quantitatively detecting eddy current energy distribution based on cross entropy |
| CN112798683A (en) * | 2020-12-09 | 2021-05-14 | 兰州理工大学 | Vortex sensor performance detection method and device based on relative entropy of tangential angle spectrum |
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Application publication date: 20190910 |