CN112067132A - Flame high-temperature measurement calibration method based on random consistency sampling technology - Google Patents

Flame high-temperature measurement calibration method based on random consistency sampling technology Download PDF

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CN112067132A
CN112067132A CN202010667314.2A CN202010667314A CN112067132A CN 112067132 A CN112067132 A CN 112067132A CN 202010667314 A CN202010667314 A CN 202010667314A CN 112067132 A CN112067132 A CN 112067132A
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temperature
flame
image
thermometer
measurement
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祝海江
王旭
李小春
刘兴旺
李卓明
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Beijing University of Chemical Technology
CETC 41 Institute
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Beijing University of Chemical Technology
CETC 41 Institute
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01JMEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J5/00Radiation pyrometry, e.g. infrared or optical thermometry
    • G01J5/0014Radiation pyrometry, e.g. infrared or optical thermometry for sensing the radiation from gases, flames
    • G01J5/0018Flames, plasma or welding
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01JMEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J5/00Radiation pyrometry, e.g. infrared or optical thermometry
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01JMEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J5/00Radiation pyrometry, e.g. infrared or optical thermometry
    • G01J5/48Thermography; Techniques using wholly visual means
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01JMEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J5/00Radiation pyrometry, e.g. infrared or optical thermometry
    • G01J5/80Calibration
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01JMEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J5/00Radiation pyrometry, e.g. infrared or optical thermometry
    • G01J2005/0077Imaging

Abstract

A flame high temperature measurement calibration method based on random consistency sampling technology belongs to the field of digital image processing and parameter measurement application research. The method mainly comprises an image acquisition module and a data processing module, and is characterized in that: the image acquisition module of the method comprises a rectangular asbestos plate, a high-definition camera, a spectral thermometer and a USB transmission line; the data processing module comprises a computer, data processing and interface display software. According to the invention, parameter calibration between temperature and image gray scale is carried out by adopting a random consistency sampling technology according to the temperature value measured by a spectrum thermometer on the round hole on the rectangular asbestos plate in the flame image and the round hole image gray scale value obtained by utilizing a digital image processing technology. The method provided by the invention can reflect the real temperature in the high-temperature process, can process abnormal measurement data points, has high measurement precision, can provide accurate data for flame temperature measurement, and has wide application in the fields of digital image processing, radiation temperature measurement and the like.

Description

Flame high-temperature measurement calibration method based on random consistency sampling technology
Technical Field
The invention relates to a method in the field of digital image processing and parameter measurement application research, in particular to a flame high-temperature measurement calibration method based on a random consistency sampling technology.
Background
With the rapid development of CCD and CMOS image sensor technologies, computer hardware technologies, and digital image processing technologies, high-speed cameras with shutter speeds exceeding 1000 frames/second are increasingly being applied to various non-contact measurement fields, such as displacement, vibration, precision part dimension measurement, temperature measurement of instantaneous high-temperature flames, and the like.
The temperature measurement based on the digital image processing technology is a non-contact measurement method which is developed rapidly, deep research is conducted at home and abroad, and the advantages of real-time performance, flexibility, non-contact and the like avoid the defects of the traditional detection method. Among countries in which research on image measurement is performed, industrial countries such as germany, the united states, japan, and the like are in the front and many principles and methods for image measurement are proposed, and research on image measurement is relatively late in our countries, and research on image measurement technology is started from the middle of the 80 s, and at that time, the main application is to measure the length by using a linear Coupled Device (CCD) and measure the diameter of a steel wire, but the accuracy is not high. In addition, CCD cameras are expensive, so image-based measurement methods are not widespread.
In recent years, with the development of semiconductors, microelectronics, computer technologies, and digital image processing technologies, the development of image measurement technologies is rapid both domestically and abroad. Due to rapid development of a CCD manufacturing process and an Integrated Circuit (IC) technology, the cost of the CCD image measurement system is reduced while the performance of the CCD image measurement system is improved, and the development of the temperature measurement technology based on the CCD image can be promoted with low cost and high performance.
At present, in published documents, a high-temperature field measurement calibration method based on a CCD image sensor mainly uses a high-temperature black body furnace to calibrate the relationship between image brightness and corresponding temperature. However, this calibration method has the following problems: (1) all radiation generated by the high temperature process is regarded as black body radiation, so that the real temperature of the high temperature process cannot be reflected; (2) the least square method commonly used in the calibration process is difficult to solve the problem of abnormal data points.
In order to obtain an accurate relationship between the brightness of the calibration image and its corresponding temperature, it is used to measure the combustion flame temperature. The invention utilizes high temperature resistant asbestos material to prepare a rectangular plate, and round holes are distributed on the surface of the rectangular plate; after a CCD image is obtained for the rectangular plate placed in the flame, a function relation curve between the initial temperature and the brightness value is calibrated according to the actual temperature value measured by each round hole and the brightness value estimated by the corresponding image. The invention establishes a high-precision multi-image temperature and brightness calibration method, and the method has important practical significance for measuring the temperature of the high-temperature flame.
Disclosure of Invention
In view of the above problems, the present invention has an object to: a flame high temperature measurement calibration method based on a random consistency sampling processing technology is provided.
The technical scheme adopted by the invention is as shown in figure 1, the method mainly comprises an image acquisition module 1 and a data processing module 2, and is characterized in that: the image temperature acquisition module 1 of the method mainly realizes that a plurality of images are obtained from different visual angles of flame and an asbestos rectangular plate in the flame through a camera, and a spectrum thermometer measures the real temperature of the flame of each round hole on the asbestos rectangular plate; the data processing system 2 realizes a data processing function and establishes a functional relationship between the actual temperature value and the corresponding image brightness value.
According to the invention, the accurate calibration of the high-temperature flame temperature measurement system can be realized, and the large error caused by the fact that the real temperature in the high-temperature process cannot be reflected by adopting the high-temperature black body furnace calibration is avoided.
The flame high-temperature measurement calibration method based on the random consistency sampling technology is characterized by comprising the following steps:
step 1): and reading temperature data measured by the spectral thermometer on the rectangular round hole point of the asbestos plate in the flame image, and recording the temperature data in the computer.
Step 2): the flame and asbestos board images were imaged at multiple angles using a camera and recorded in a computer.
Step 3): according to the data recorded in the computer in the previous two steps, a random consistency sampling processing technology is adopted for data processing, and a functional relation between the flame image radiant energy and the recording temperature of the spectrum thermometer is calibrated, and the specific process is as follows:
firstly, the relationship between the gray value of the flame CCD image and the corresponding temperature is deduced by the principle of colorimetric thermometry. The formula of the colorimetric thermometry is as follows (1):
Figure BDA0002580866830000031
wherein R and B are average gray values of an R channel and a B channel of the flame image; lambda [ alpha ]r,λgAnd λbWavelengths of red, green and blue light; t is a flame temperature value measured by a spectrum thermometer; c is a constant in planck's radiation law, with a value of 0.0144 mK; k is an unknown constant and needs to be calibrated. If it is
Figure BDA0002580866830000032
b=-(ln K+5ln(λrb) The unknown constant K to be calibrated is contained in the parameter b, and a and b are the parameters to be calibrated. Then, equation (1) is transformed into:
ln(R/B)=a·T-1+b (2)
and secondly, randomly selecting two groups of sample values and estimating the initial model of the formula (2) by adopting a random consistency sampling technology according to the average gray scale ratio R/B of the R channel and the B channel estimated from the position of the asbestos plate circular hole in the flame CCD image and the temperature value T measured by the spectrum thermometer.
Substituting all recorded R/B and T into the estimated model to calculate all errorsi(i denotes the number of measurement points)
i=||ln(R/B)-(a·T-1+b)|| (3)
Setting an error threshold value tau, wherein the threshold value is usually determined by using a manual experience selection method. And (4) taking the data points with the error larger than tau as abnormal data points, counting the number of the data points meeting the threshold value smaller than tau in the model established by two groups of samples randomly, and finding a group of data points with the least abnormal data points to fit the final model.
Step 4): and 3) measuring the temperature value of any point in the flame CCD image according to the model established in the step 3).
Drawings
FIG. 1 is a block diagram of the system of the present invention;
in the figure: 1 is an image acquisition module, comprising: a1, rectangular asbestos board, A2, camera, A3, USB transmission line and spectrum thermometer, 2 is data processing module, mainly including computer and data processing and display software.
FIG. 2 is a graph plotting temperature values and gray scale values
Detailed Description
The specific structure of this embodiment, referring to fig. 1, this precaution mainly includes image acquisition module 1, data processing module 2, its characterized in that: the image acquisition module 1 for precaution comprises a rectangular asbestos plate A1, a high-definition camera A2 and a USB transmission line A3; the data processing and display interface system 2 comprises a computer, data processing and interface display software; wherein, the high-definition camera and the spectrum thermometer are connected with the computer through a USB transmission line A3.
The contents of the flame pyrometry calibration method based on the random consistency sampling technology of the present invention are further described in detail with reference to the following specific examples:
step 1): images including flames and a rectangular asbestos board were captured by a high-definition camera.
Step 2): processing the flame image to obtain a temperature value and a gray value corresponding to the round hole in the required rectangular asbestos plate;
measuring the temperature of each round hole on the rectangular asbestos plate by using a spectral temperature measuring instrument, and recording the temperature value; then, the average gray values of the red channel R and the blue channel B of the corresponding round hole images in the flame images are read by utilizing an image processing technology. The temperature values, the average gray values of the red channel R and the blue channel B are shown in the following table.
Temperature value (Unit K) R B
1273 17.40 12.18
1330 26.16 14.42
1385 33.23 15.46
1415 46.28 16.90
1477 72.08 20.36
1525 108.25 28.43
1573 150.76 35.34
1626 206.87 44.25
Step 3): abnormal data elimination and parameter calibration are carried out on the temperature value and the gray value by utilizing a random consistency sampling technology;
according to the temperature value and the gray value obtained by measuring the round hole on the rectangular asbestos plate, randomly selecting two groups of samples and estimating parameters a and b according to the formula (2); then, setting an error threshold tau to be 0.1, wherein the threshold is determined by a manual experience selection method, and counting the number of data point pairs (R/B, T) smaller than the error threshold; and taking a group of data with the largest number for parameter calibration, taking a data point smaller than the error threshold value for re-calibrating the parameters, and drawing a curve as shown in FIG. 2. In addition, the method can also remove abnormal data points, such as the abnormal points are not involved in calibration after being removed in figure 2.
And 4) calculating a temperature value according to the calibrated parameters by using the values of any point R and B in the flame CCD image according to the calibrated parameters.

Claims (2)

1. A flame high temperature measurement calibration method based on random consistency sampling technology is characterized in that: the method comprises image acquisition (1) and a data processing module (2), wherein the image acquisition module (1) of the method comprises a rectangular asbestos plate (A1), a high-definition camera (A2), a spectral thermometer and a USB transmission line (A3); the data processing module (2) comprises a computer and related software; the high-definition camera (A2) and the spectrum thermometer are connected with a computer through a USB transmission line (A3) to acquire images and measure temperature.
2. The flame pyrometry calibration method applied to the random consistency sampling technique of claim 1, characterized by the steps of:
step 1): and reading temperature data measured by the spectral thermometer on the rectangular round hole point of the asbestos plate in the flame image, and recording the temperature data in the computer.
Step 2): the flame and asbestos board images were imaged at multiple angles using a high speed camera and recorded in a computer.
Step 3): according to the data recorded in the computer in the previous two steps, a random consistency sampling processing technology is adopted for data processing, and a functional relation between the flame image radiant energy and the recording temperature of the spectrum thermometer is calibrated, and the specific process is as follows:
firstly, the relationship between the gray value of the flame CCD image and the corresponding temperature is deduced by the principle of colorimetric thermometry.
The formula of the colorimetric thermometry is as follows (1):
Figure FDA0002580866820000011
wherein R and B are average gray values of an R channel and a B channel of the flame image; lambda [ alpha ]r,λgAnd λbWavelengths of red, green and blue light; t is a flame temperature value measured by a spectrum thermometer; c is a constant in planck's radiation law, with a value of 0.0144 mK; k is an unknown constant and needs to be calibrated. The unknown constant K to be calibrated is contained in the parameter b, and a and b are parameters to be calibrated. Then, equation (1) is transformed into:
ln(R/B)=a·T-1+b (2)
and secondly, randomly selecting two groups of sample values and estimating the initial model of the formula (2) by adopting a random consistency sampling technology according to the average gray scale ratio R/B of the R channel and the B channel estimated from the position of the asbestos plate circular hole in the flame CCD image and the temperature value T measured by the spectrum thermometer.
Substituting all recorded R/B and T into the estimated model to calculate all errorsi(i denotes the number of measurement points)
i=||ln(R/B)-(a·T-1+b)|| (3)
Setting an error threshold tau, making the data points with the error larger than tau be abnormal data points, counting the number of the data points meeting the threshold smaller than tau in the model established by randomly adopting two groups of samples, and finding a group of data points with the least abnormal data points to fit the final model; τ is 0.1;
step 4): and measuring the temperature value of any point in the flame CCD image according to the model established in the step 3).
CN202010667314.2A 2020-07-13 2020-07-13 Flame high-temperature measurement calibration method based on random consistency sampling technology Pending CN112067132A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114509166A (en) * 2022-01-27 2022-05-17 重庆大学 High transient high temperature plasma temperature measurement system

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105354859A (en) * 2015-12-09 2016-02-24 华中科技大学 Flame visible radiation calibration method
CN105606222A (en) * 2015-09-06 2016-05-25 东南大学 Flame three-dimensional temperature field measurement imaging device, measuring device and measuring method
CN108389169A (en) * 2018-03-07 2018-08-10 哈尔滨工业大学 A kind of temperature rebuilding method applied to the imaging of flame light field refocusing
WO2019048102A1 (en) * 2017-09-06 2019-03-14 Brainlab Ag Determining the relative position between a thermal camera and a 3d camera using a hybrid phantom and hybrid phantom
CN109556736A (en) * 2018-12-04 2019-04-02 南京森林警察学院 A kind of fire scene temperature measuring device and method based near infrared band colorimetric method

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105606222A (en) * 2015-09-06 2016-05-25 东南大学 Flame three-dimensional temperature field measurement imaging device, measuring device and measuring method
CN105354859A (en) * 2015-12-09 2016-02-24 华中科技大学 Flame visible radiation calibration method
WO2019048102A1 (en) * 2017-09-06 2019-03-14 Brainlab Ag Determining the relative position between a thermal camera and a 3d camera using a hybrid phantom and hybrid phantom
CN108389169A (en) * 2018-03-07 2018-08-10 哈尔滨工业大学 A kind of temperature rebuilding method applied to the imaging of flame light field refocusing
CN109556736A (en) * 2018-12-04 2019-04-02 南京森林警察学院 A kind of fire scene temperature measuring device and method based near infrared band colorimetric method

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
王立新;钱扬义;范婉贞;许雯辉;唐文秀;: "利用手持技术探究加热过程中石棉网上表面的温度", 化学教育(中英文), no. 21, pages 1 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114509166A (en) * 2022-01-27 2022-05-17 重庆大学 High transient high temperature plasma temperature measurement system
CN114509166B (en) * 2022-01-27 2024-02-23 重庆大学 High-transient high-temperature plasma temperature measurement system

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