CN103091252A - Material emissivity measuring method based on infrared thermometer - Google Patents

Abstract

The invention discloses a material emissivity measuring method based on an infrared thermometer and belongs to the technical field of thermal performance measurement of high-temperature opaque materials. The method disclosed by the invention aims to solve the problems that conventional material emissivity measuring methods are poor in measuring result accuracy, complex in use and low in measuring speed. The method disclosed by the invention comprises the following steps of firstly measuring the temperature of a blackbody furnace by using an infrared thermometer, obtaining the stray radiation energy received by the infrared thermometer through calculating, measuring the surface temperature of a test piece made from the to-be-measured material by using a thermocouple thermodetector and obtaining the true surface temperature of the test piece. According to the invention, five measuring temperature values are obtained through measuring the surface temperature of the test piece under the condition of five set emissivities of the infrared thermometer; five material emissivities are obtained through bringing the five set emissivities and the five measuring temperature values into a calculating formula; and the emissivity of the to-be-measured material is obtained through taking the average. The method disclosed by the invention is mainly applied to the technical field of emissivity measurement of the high-temperature opaque materials.

Description

Material emissivity measurement method based on infrared thermometer

Technical field

The present invention relates to the measuring method of a kind of material emissivity measurement method based on infrared thermometer and deduction stray radiation, belong to high temperature opaque material thermophysical property measurement technical field.

Background technology

Emissivity be defined as material surface radiation energy and blackbody radiation under equal temperature can ratio.The emissivity of various material surfaces is physical quantitys of exosyndrome material surface emissivity ability, is an extremely important thermal physical property parameter.According to wavelength coverage, emissivity can be divided into full spectral emittance, spectral emittance and band emission rate; Can be divided into hemispherical emissivity and direction emissivity according to direction of measurement.

The measurement of material emissivity relates to a plurality of fields such as Aero-Space, military affairs, chemical industry, building, medical treatment, new forms of energy and atmospheric science.Its typical case uses and comprises: the measurement of the early warning of the ablation on surface, guided missile and interception, railroad car axle temperature, remote sensing radiometric technique etc. when the infrared stealth of aircraft skin, aerospacecraft atmospheric reentry.For the emissivity measurement of material, a lot of researchs were done by the states such as the U.S., France, Britain, Japan.Existing measuring method mainly contains three kinds: (1) calorimetry, and by determining the hot-fluid of sample radiation or absorption in stable state or transient process, utilize energy-balance equation to try to achieve emissivity, general multiplex in the measurement of hemispherical emissivity; (2) reflectometry according to law of conservation of energy and Kirchhoff's law, projects the radiation energy of known strength on tested opaque sample surfaces, and measures surface reflection energy with reflectometer, tries to achieve the reflectivity of sample and then calculates emissivity; (3) energy method is directly measured the radiation energy of sample, according to Planck law, calculates the emissivity of sample surfaces by the definition of emissivity.

Summary of the invention

The objective of the invention is poor for the measurement result degree of accuracy that solves current material emissivity measurement method, use complexity and the slow problem of measuring speed, the invention provides a kind of material emissivity measurement method based on infrared thermometer.

Described material emissivity measurement method based on infrared thermometer is to adopt infrared thermometer, thermocouple probe, thermocouple temperature measurement instrument, blackbody furnace and temperature control system to realize the measurement of material emissivity, described temperature control system comprises heating furnace, well heater, temperature collecting device and temperature patrol inspection are controlled instrument, described heating furnace is provided with circular light hole, realizes that the measuring process of material emissivity is:

Step 1, at first detected materials is made into circular test specimen, wherein detected materials is opaque material, then the entrance pupil mouth of infrared thermometer is aimed at the light hole of blackbody furnace, and the emissivity ε of described blackbody furnace=1, temperature are T _b1, to the adjusting that collimates of the thermometric light path of infrared thermometer, make the light hole of blackbody furnace and the entrance pupil mouth of infrared thermometer be centered close to same level height and staggered relatively, the distance between the light hole of infrared thermometer entrance pupil mouth and blackbody furnace

Wherein,

Be the parameter of infrared thermometer, D represents the distance between the infrared thermometer circular test specimen relative with it, S represent infrared thermometer and its to the area of a circle at place, circular test specimen center to be measured, d is the diameter of circular test specimen, the emissivity of infrared thermometer is ε ' _b, the measurement temperature that infrared thermometer is measured the blackbody furnace that obtains is T _mb1,

The temperature of adjusting blackbody furnace is T _b2, and the measurement temperature that adopts infrared thermometer to measure the acquisition blackbody furnace is T _mb2,

Adjusting the temperature of setting blackbody furnace is T _b3, and the measurement temperature that adopts infrared thermometer to measure the acquisition blackbody furnace is T _mb3, wherein, T _b1, T _b2, T _b3Value in room temperature to 1500 ℃ temperature range, and T _b1＜T _b2＜T _b3According to parameter T _mb1, T _mb2, T _mb3Adopt deduction stray radiation algorithm to calculate the stray radiation energy;

Step 2, circular test specimen is inlayed and be fixed in the circular light hole of heating furnace, and described circular light hole is concentric with circular test specimen, to the adjusting that collimates of the mensuration light path of infrared thermometer, make the circular light hole center of heating furnace and infrared thermometer entrance pupil mouth be centered close to same level height and staggered relatively;

Step 3, open the heating furnace power switch, begin circular test specimen heating;

Step 4, when circular test specimen is heated to the experiment measuring temperature, when utilizing temperature patrol inspection to control instrument to make circular test specimen keep constant temperature, the thermocouple probe of thermocouple temperature measurement instrument is contacted the center on circular test specimen surface, measure the measurement temperature value T on circular test specimen surface _r, and it is measured temperature value T _rTrue temperature as circular test specimen;

The scope of the experiment measuring temperature described in described step 4 is 373～1773K.

Step 5, unlatching infrared thermometer, its emissivity is ε ' ₁, and keep distance between the outside surface center of infrared thermometer entrance pupil mouth center and circular test specimen The outside surface center of the circular test specimen of infrared thermometer entrance pupil mouth centrally aligned is measured, and obtains measuring temperature value T _m1

Step 6, infrared thermometer is set the emissivity value successively and be adjusted into ε ' ₂, ε ' ₃, ε ' ₄, ε ' ₅, and after the setting emissivity of each adjustment infrared thermometer, execution in step five obtains corresponding measurement temperature value T successively _m2, T _m3, T _m4, T _m5

The stray radiation energy that calculates in the measurement temperature value of the circular test specimen that obtains in step 7, integrating step four, step 5 and step 6 and step 1 calculates the material emissivity ε of detected materials in room temperature to 1500 ℃ temperature range.

Utilization deduction stray radiation algorithm described in described step 1 calculates the stray radiation energy, and its concrete grammar is:

The service band of described infrared thermometer is atmospheric window, and the thermometric formula table of infrared thermometer is shown,

ε′f(T _m)+(1-ε′)f(T _e)＝εf(T _r)+(1-α)f(T _e)+g(T _e) (1)

In formula, T _mBe the temperature that infrared thermometer records, unit K;

T _rBy the true temperature of the circular test specimen of survey, unit K;

T _eBe environment temperature, unit K;

ε by the emissivity of the circular test specimen of survey;

ε ' sets emissivity for infrared thermometer;

α by the Surface absorption rate of the circular test specimen of survey;

g(T _e) be the stray radiation energy;

The order circular test specimen of surveying is grey body, and α=ε is arranged, bring in formula (1) to get,

ε′f(T _m)+(1-ε′)f(T _e)＝εf(T _r)+(1-ε)f(T _e)+g(T _e) (2)

Get according to Planck law,

f(T)＝CT ⁿ (3)

In formula, C is constant;

N is index, according to the service band value of infrared thermometer 1,

When the service band of described infrared thermometer is 3～5 μ m, get n=9.3,

When the service band of described infrared thermometer is 8～14 μ m, get n=4,

To get in formula (3) substitution formula (2),

${\mathrm{\ϵ}}^{\′}{T}_m^n+(1-{\mathrm{\ϵ}}^{\′})T_e^n=\mathrm{\ϵ}{T}_r^n+(1-\mathrm{\ϵ})T_e^n+h\left(T_e\right)---\left(4\right)$

In formula, $h\left(T_e\right)=\frac{g\left(T_e\right)}{C}$

Measurement temperature T with blackbody furnace in step 1 _mb1, T _mb2, T _mb3And environment temperature T _eSubstitution (4) formula gets,

$h_1\left(T_e\right)={\mathrm{\ϵ}}_b^{\′}{T}_{\mathrm{mb}1}^n+(1-{\mathrm{\ϵ}}_b^{\′})T_e^n-T_{b1}^n---\left(5a\right)$

$h_2\left(T_e\right)={\mathrm{\ϵ}}_b^{\′}{T}_{\mathrm{mb}2}^n+(1-{\mathrm{\ϵ}}_b^{\′})T_e^n-T_{b2}^n---\left(5b\right)$

$h_3\left(T_e\right)={\mathrm{\ϵ}}_b^{\′}{T}_{\mathrm{mb}3}^n+(1-{\mathrm{\ϵ}}_b^{\′})T_e^n-T_{b3}^n---\left(5c\right)$

Averaging can get stray radiation and can be expressed as,

$g\left(T_e\right)=C\frac{h_1\left(T_e\right)+h_2\left(T_e\right)+h_3\left(T_e\right)}{3}---\left(6\right)$

Calculate the material emissivity ε of detected materials in room temperature to 1500 ℃ temperature range in described step 7, its concrete methods of realizing is,

Material emissivity ε expression formula is as follows,

$\mathrm{\ϵ}=\frac{{\mathrm{\ϵ}}^{\′}(T_m^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(7\right)$

In step 5 and step 6, successively with five emissivity ε ' setting value ε ' of infrared thermometer ₁, ε ' ₂, ε ' ₃, ε ' ₄, ε ' ₅With corresponding five measurement temperature value T _m1, T _m2, T _m3, T _m4, T _m5Obtain five material emissivity in substitution formula (7) respectively,

${\mathrm{\ϵ}}_1=\frac{{\mathrm{\ϵ}}_1^{\′}(T_{m1}^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(8a\right)$

${\mathrm{\ϵ}}_2=\frac{{\mathrm{\ϵ}}_2^{\′}(T_{m2}^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(8b\right)$

${\mathrm{\ϵ}}_3=\frac{{\mathrm{\ϵ}}_3^{\′}(T_{m3}^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(8c\right)$

${\mathrm{\ϵ}}_4=\frac{{\mathrm{\ϵ}}_4^{\′}(T_{m4}^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(8d\right)$

${\mathrm{\ϵ}}_5=\frac{{\mathrm{\ϵ}}_5^{\′}(T_{m5}^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(8e\right)$

To five material emissivity ε obtained above ₁, ε ₂, ε ₃, ε ₄, ε ₅Average and namely obtain the emissivity ε of detected materials in room temperature to 1500 ℃ temperature range and be:

$\mathrm{\ϵ}=\frac{{\mathrm{\ϵ}}_1+{\mathrm{\ϵ}}_2+{\mathrm{\ϵ}}_3+{\mathrm{\ϵ}}_4+{\mathrm{\ϵ}}_5}{5}.---\left(9\right)$

Present embodiment is that the stray radiation energy that calculates in the true temperature, step 1 of the circular test specimen that in the circular test specimen measured temperature under five different set emissivity, step 4, the thermocouple temperature measurement instrument records according to infrared thermometer in described step 7 calculates the material emissivity ε of circular test specimen in room temperature to 1500 ℃ temperature range.

At first the present invention uses infrared thermometer that the temperature of blackbody furnace is measured, and the stray radiation energy that receives by calculating infrared thermometer, then use the thermocouple temperature measurement instrument that the circular test specimen surface temperature of opaque material is measured, obtained the true temperature on circular test specimen surface; Secondly the present invention designs to have realized setting at five kinds and uses infrared thermometer to measure circular test specimen surface temperature under the emissivity condition, obtain five and measure temperature value, utilize five to set emissivity and five measurement temperature value substitution computing formula, obtain circular test specimen emissivity value, calculated the opaque material emissivity of deduction stray radiation.

The advantages such as a kind of beneficial effect of bringing based on the material emissivity measurement method of infrared thermometer provided by the invention is really, and it uses, and simple, measuring speed improves 6%～10%, the measurement result degree of accuracy has improved 5%, and construction cost is low, and is applied widely.

Description of drawings

Fig. 1 is the device schematic diagram that realization the present invention is based on the material emissivity measurement method of infrared thermometer.

Embodiment

Embodiment one: present embodiment is described referring to Fig. 1, the described material emissivity measurement method based on infrared thermometer of present embodiment is to adopt infrared thermometer 1, thermocouple probe 4, thermocouple temperature measurement instrument 7, blackbody furnace 8 and temperature control system to realize the measurement of material emissivity, described temperature control system comprises heating furnace 2, well heater 3, temperature collecting device 5 and temperature patrol inspection are controlled instrument 6, described heating furnace 2 is provided with circular light hole, realizes that the measuring process of material emissivity is:

Step 1, at first detected materials is made into circular test specimen 9, wherein detected materials is opaque material, then the entrance pupil mouth of infrared thermometer 1 is aimed at the light hole of blackbody furnace 8, and the emissivity ε of described blackbody furnace 8=1, temperature are T _b1, to the adjusting that collimates of the thermometric light path of infrared thermometer 1, make the light hole of blackbody furnace 8 and the entrance pupil mouth of infrared thermometer 1 be centered close to same level height and staggered relatively, the distance between the light hole of infrared thermometer 1 entrance pupil mouth and blackbody furnace 8

Wherein,

Be the parameter of infrared thermometer 1, D represents the distance between infrared thermometer 1 and circular test specimen 9, S represent infrared thermometer 1 with its to the area of a circle at circular test specimen to be measured 9 places, center, d is the diameter of circular test specimen 9, the emissivity of infrared thermometer 1 is ε ' _b, the measurement temperature that infrared thermometer 1 is measured the blackbody furnace 8 that obtains is T _mb1,

The temperature of adjusting blackbody furnace 8 is T _b2, and the measurement temperature that adopts infrared thermometer 1 to measure acquisition blackbody furnace 8 is T _mb2,

The temperature of adjusting blackbody furnace 8 is T _b3, and the measurement temperature that adopts infrared thermometer 1 to measure acquisition blackbody furnace 8 is T _mb3, wherein, T _b1, T _b2, T _b3Value in room temperature to 1500 ℃ temperature range, and T _b1＜T _b2＜T _b3According to parameter T _mb1, T _mb2, T _mb3Adopt deduction stray radiation algorithm to calculate the stray radiation energy;

Step 2, circular test specimen 9 is inlayed and be fixed in the circular light hole of heating furnace 2, and described circular light hole is concentric with circular test specimen 9,

To the adjusting that collimates of the mensuration light path of infrared thermometer 1, make the circular light hole center of heating furnace 2 and infrared thermometer 1 entrance pupil mouth be centered close to same level height and staggered relatively;

Step 3, open heating furnace 2 power switches, begin circular test specimen 9 heating;

Step 4, when circular test specimen 9 is heated to the experiment measuring temperature, when utilizing temperature patrol inspection to control instrument 6 to make circular test specimen 9 keep constant temperature, the thermocouple probe 4 of thermocouple temperature measurement instrument 7 is contacted the center on circular test specimen 9 surfaces, measure the measurement temperature value T on circular test specimen 9 surfaces _r, and it is measured temperature value T _rTrue temperature as circular test specimen 9;

Step 5, unlatching infrared thermometer 1, its emissivity is ε ' ₁, and keep distance between the outside surface center of infrared thermometer 1 entrance pupil mouth center and circular test specimen 9

The outside surface center of the infrared thermometer 1 circular test specimen 9 of entrance pupil mouth centrally aligned is measured, and obtains measuring temperature value T _m1

Step 6, successively infrared thermometer 1 is set the emissivity value and be adjusted into ε ' ₂, ε ' ₃, ε ' ₄, ε ' ₅, and after the setting emissivity of each adjustment infrared thermometer 1, execution in step five obtains corresponding measurement temperature value T successively _m2, T _m3, T _m4, T _m5

The stray radiation energy that calculates in the measurement temperature value of the circular test specimen 9 that obtains in step 7, integrating step four, step 5 and step 6 and step 1 calculates the material emissivity ε of detected materials in room temperature to 1500 ℃ temperature range.

Embodiment two: the difference of present embodiment and embodiment one is, the utilization deduction stray radiation algorithm described in described step 1 calculates the stray radiation energy, and its concrete grammar is:

The service band of described infrared thermometer 1 is atmospheric window, and the thermometric formula table of infrared thermometer 1 is shown,

ε′f(T _m)+(1-ε′)f(T _e)＝εf(T _r)+(1-α)f(T _e)+g(T _e) (1)

In formula, T _mBe the temperature that infrared thermometer 1 records, unit K;

T _rBy the true temperature of the circular test specimen 9 of survey, unit K;

T _eBe environment temperature, unit K;

ε by the emissivity of the circular test specimen 9 of survey;

ε ' is that infrared thermometer 1 is set emissivity;

α by the Surface absorption rate of the circular test specimen 9 of survey;

g(T _e) be the stray radiation energy;

The order circular test specimen of surveying is grey body, and α=ε is arranged, bring in formula (1) to get,

ε′f(T _m)+(1-ε′)f(T _e)＝εf(T _r)+(1-ε)f(T _e)+g(T _e) (2)

Get according to Planck law,

f(T)＝CT ⁿ (3)

In formula, C is constant;

N is index, according to the service band value of infrared thermometer 1,

To get in formula (3) substitution formula (2),

${\mathrm{\ϵ}}^{\′}{T}_m^n+(1-{\mathrm{\ϵ}}^{\′})T_e^n=\mathrm{\ϵ}{T}_r^n+(1-\mathrm{\ϵ})T_e^n+h\left(T_e\right)---\left(4\right)$

In formula, $h\left(T_e\right)=\frac{g\left(T_e\right)}{C}$

Measurement temperature T with blackbody furnace in step 18 _mb1, T _mb2, T _mb3And environment temperature T _eSubstitution (4) formula gets,

$h_1\left(T_e\right)={\mathrm{\ϵ}}_b^{\′}{T}_{\mathrm{mb}1}^n+(1-{\mathrm{\ϵ}}_b^{\′})T_e^n-T_{b1}^n---\left(5a\right)$

$h_2\left(T_e\right)={\mathrm{\ϵ}}_b^{\′}{T}_{\mathrm{mb}2}^n+(1-{\mathrm{\ϵ}}_b^{\′})T_e^n-T_{b2}^n---\left(5b\right)$

$h_3\left(T_e\right)={\mathrm{\ϵ}}_b^{\′}{T}_{\mathrm{mb}3}^n+(1-{\mathrm{\ϵ}}_b^{\′})T_e^n-T_{b3}^n---\left(5c\right)$

Averaging can get stray radiation and can be expressed as,

$g\left(T_e\right)=C\frac{h_1\left(T_e\right)+h_2\left(T_e\right)+h_3\left(T_e\right)}{3}.---\left(6\right)$

Embodiment three: the difference of present embodiment and embodiment two is, calculates the material emissivity ε of detected materials in room temperature to 1500 ℃ temperature range in described step 7, and its concrete methods of realizing is,

Material emissivity ε expression formula is as follows,

$\mathrm{\ϵ}=\frac{{\mathrm{\ϵ}}^{\′}(T_m^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(7\right)$

In step 5 and step 6, successively with five emissivity ε ' setting value ε ' of infrared thermometer 1 ₁, ε ' ₂, ε ' ₃, ε ' ₄, ε ' ₅With corresponding five measurement temperature value T _m1, T _m2, T _m3, T _m4, T _m5Obtain five material emissivity in substitution formula (7) respectively,

${\mathrm{\ϵ}}_1=\frac{{\mathrm{\ϵ}}_1^{\′}(T_{m1}^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(8a\right)$

${\mathrm{\ϵ}}_2=\frac{{\mathrm{\ϵ}}_2^{\′}(T_{m2}^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(8b\right)$

${\mathrm{\ϵ}}_3=\frac{{\mathrm{\ϵ}}_3^{\′}(T_{m3}^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(8c\right)$

${\mathrm{\ϵ}}_4=\frac{{\mathrm{\ϵ}}_4^{\′}(T_{m4}^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(8d\right)$

${\mathrm{\ϵ}}_5=\frac{{\mathrm{\ϵ}}_5^{\′}(T_{m5}^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(8e\right)$

To five material emissivity ε obtained above ₁, ε ₂, ε ₃, ε ₄, ε ₅Average and namely obtain the emissivity ε of detected materials in room temperature to 1500 ℃ temperature range and be:

$\mathrm{\ϵ}=\frac{{\mathrm{\ϵ}}_1+{\mathrm{\ϵ}}_2+{\mathrm{\ϵ}}_3+{\mathrm{\ϵ}}_4+{\mathrm{\ϵ}}_5}{5}.---\left(9\right)$

Present embodiment is that the stray radiation energy that calculates in the true temperature, step 1 of the circular test specimen 9 that in circular test specimen 9 measured temperatures under five different set emissivity, step 4, thermocouple temperature measurement instrument 7 records according to infrared thermometer 1 in described step 7 calculates the material emissivity ε of circular test specimen 9 in room temperature to 1500 ℃ temperature range.

Embodiment four: the difference of present embodiment and embodiment one is, the scope of the experiment measuring temperature described in described step 4 is 373～1773K.

Embodiment five: the difference of present embodiment and embodiment two is, when the service band of described infrared thermometer 1 is 3～5 μ m, gets n=9.3.

Embodiment six: the difference of present embodiment and embodiment two is, when the service band of described infrared thermometer 1 is 8～14 μ m, gets n=4.

Infrared temperature-test technology has noncontact, the advantage such as directly perceived, highly sensitive, quick, safe, patrols and examines at high-tension bus-bar, the civil area such as commercial production is widely used; On the other hand, the thermal infrared imaging technology also is widely applied in the military domain such as scouting and guidance, camouflage design and detection.Infrared thermometer is generally operational in atmospheric window wave band 3 μ m～5 μ m and wave band 8 μ m～14 μ m, and the emissivity measurement of these two wave bands has great importance.

Infrared thermometer is to be abutted against the infrared radiation of receiving the measured surface emission to determine its temperature, and during measurement, effective radiation that infrared thermometer receives comprises three parts: target self radiation, reflection environment radiation and stray radiation.

At first the present invention uses the temperature of 1 pair of blackbody furnace 8 of infrared thermometer to measure, and the stray radiation energy that receives by calculating infrared thermometer 1, then use circular test specimen 9 surface temperatures of 7 pairs of opaque materials of thermocouple temperature measurement instrument to measure, obtained the true temperature on circular test specimen 9 surfaces; Secondly the present invention designs to have realized setting at five kinds and uses infrared thermometer 1 to measure circular test specimen 9 surface temperatures under the emissivity condition, obtain five and measure temperature value, utilize five to set emissivity and five measurement temperature value substitution computing formula, obtain circular test specimen 9 emissivity values, calculated the emissivity of the detected materials of deduction stray radiation.

Claims (6)

1. based on the material emissivity measurement method of infrared thermometer, it is characterized in that, it is to adopt infrared thermometer (1), thermocouple probe (4), thermocouple temperature measurement instrument (7), blackbody furnace (8) and temperature control system to realize the measurement of material emissivity, described temperature control system comprises heating furnace (2), well heater (3), temperature collecting device (5) and temperature patrol inspection are controlled instrument (6), described heating furnace (2) is provided with circular light hole, realizes that the measuring process of material emissivity is:

Step 1, at first detected materials is made into circular test specimen (9), wherein detected materials is opaque material, the entrance pupil mouth of infrared thermometer (1) is aimed at the light hole of blackbody furnace (8), the emissivity ε of described blackbody furnace (8)=1, temperature are T again _b1To the adjusting that collimates of the thermometric light path of infrared thermometer (1), make the light hole of blackbody furnace (8) and the entrance pupil mouth of infrared thermometer (1) be centered close to same level height and staggered relatively, the distance between the light hole of infrared thermometer (1) entrance pupil mouth and blackbody furnace (8)

Wherein,

It is the parameter of infrared thermometer (1), D represents the distance between infrared thermometer (1) and circular test specimen to be measured (9), S represent infrared thermometer (1) with to the area of a circle at circular test specimen to be measured (9) place, center, d is the diameter of circular test specimen (9), and the emissivity of infrared thermometer (1) is ε ' _b, the measurement temperature that infrared thermometer (1) is measured the blackbody furnace (8) that obtains is T _mb1,

The temperature of adjusting blackbody furnace (8) is T _b2, and the measurement temperature that adopts infrared thermometer (1) to measure acquisition blackbody furnace (8) is T _mb2,

The temperature of adjusting blackbody furnace (8) is T _b3, and the measurement temperature that adopts infrared thermometer (1) to measure acquisition blackbody furnace (8) is T _mb3, wherein, T _b1, T _b2, T _b3Value in room temperature to 1500 ℃ temperature range, and T _b1＜T _b2＜T _b3According to parameter T _mb1, T _mb2, T _mb3Adopt deduction stray radiation algorithm to calculate the stray radiation energy;

Step 2, circular test specimen (9) is inlayed and be fixed in the circular light hole of heating furnace (2), and described circular light hole is concentric with circular test specimen (9),

To the adjusting that collimates of the mensuration light path of infrared thermometer (1), make the circular light hole center of heating furnace (2) and infrared thermometer (1) entrance pupil mouth be centered close to same level height and staggered relatively;

Step 3, open heating furnace (2) power switch, begin circular test specimen (9) is heated;

Step 4, when circular test specimen (9) is heated to the experiment measuring temperature, when utilizing temperature patrol inspection to control instrument (6) to make circular test specimen (9) keep constant temperature, the thermocouple probe (4) of thermocouple temperature measurement instrument (7) is contacted the center on circular test specimen (9) surface, measure the measurement temperature value T on circular test specimen (9) surface _r, and it is measured temperature value T _rTrue temperature as circular test specimen (9);

Step 5, unlatching infrared thermometer (1), its emissivity is ε ' ₁, and keep distance between the outside surface center of infrared thermometer (1) entrance pupil mouth center and circular test specimen (9)

The outside surface center of the circular test specimen of infrared thermometer (1) entrance pupil mouth centrally aligned (9) is measured, and obtains measuring temperature value T _m1

Step 6, infrared thermometer (1) is set the emissivity value successively and be adjusted into ε ' ₂, ε ' ₃, ε ' ₄, ε ' ₅, and after the setting emissivity of each adjustment infrared thermometer (1), execution in step five obtains corresponding measurement temperature value T successively _m2, T _m3, T _m4, T _m5

The stray radiation energy that calculates in the measurement temperature value of the circular test specimen (9) that obtains in step 7, integrating step four, step 5 and step 6 and step 1 calculates the material emissivity ε of detected materials in room temperature to 1500 ℃ temperature range.

2. the material emissivity measurement method based on infrared thermometer according to claim 1, is characterized in that, the utilization deduction stray radiation algorithm described in described step 1 calculates the stray radiation energy, and its concrete grammar is:

The service band of described infrared thermometer (1) is atmospheric window, and the thermometric formula table of infrared thermometer (1) is shown,

ε′f(T _m)+(1-ε′)f(T _e)＝εf(T _r)+(1-α)f(T _e)+g(T _e) (1)

In formula, T _mBe the temperature that infrared thermometer (1) records, unit K;

T _rBy the true temperature of the circular test specimen of survey (9), unit K;

T _eBe environment temperature, unit K;

ε by the emissivity of the circular test specimen of survey (9);

ε ' is that infrared thermometer (1) is set emissivity;

α by the Surface absorption rate of the circular test specimen of survey (9);

g(T _e) be the stray radiation energy;

The order circular test specimen of surveying is grey body, and α=ε is arranged, bring in formula (1) to get,

ε′f(T _m)+(1-ε′)f(T _e)＝εf(T _r)+(1-ε)f(T _e)+g(T _e) (2)

Get according to Planck law,

f(T)＝CT ⁿ (3)

In formula, C is constant;

N is index, according to the service band value of infrared thermometer (1),

To get in formula (3) substitution formula (2),

${\mathrm{\ϵ}}^{\′}{T}_m^n+(1-{\mathrm{\ϵ}}^{\′})T_e^n=\mathrm{\ϵ}{T}_r^n+(1-\mathrm{\ϵ})T_e^n+h\left(T_e\right)---\left(4\right)$

In formula, $h\left(T_e\right)\text{=}\frac{g\left(T_e\right)}{C}$

Measurement temperature T with blackbody furnace in step 1 (8) _mb1, T _mb2, T _mb3And environment temperature T _eSubstitution (4) formula gets,

$h_1\left(T_e\right)={\mathrm{\ϵ}}_b^{\′}{T}_{\mathrm{mb}1}^n+(1-{\mathrm{\ϵ}}_b^{\′})T_e^n-T_{b1}^n---\left(5a\right)$

$h_2\left(T_e\right)={\mathrm{\ϵ}}_b^{\′}{T}_{\mathrm{mb}2}^n+(1-{\mathrm{\ϵ}}_b^{\′})T_e^n-T_{b2}^n---\left(5b\right)$

$h_3\left(T_e\right)={\mathrm{\ϵ}}_b^{\′}{T}_{\mathrm{mb}3}^n+(1-{\mathrm{\ϵ}}_b^{\′})T_e^n-T_{b3}^n---\left(5c\right)$

Averaging can get stray radiation and can be expressed as,

$g\left(T_e\right)=C\frac{h_1\left(T_e\right)+h_2\left(T_e\right)+h_3\left(T_e\right)}{3}---\left(6\right)$

3. the material emissivity measurement method based on infrared thermometer according to claim 2, is characterized in that, calculates the material emissivity ε of detected materials in room temperature to 1500 ℃ temperature range in described step 7, and its concrete methods of realizing is,

Material emissivity ε expression formula is as follows,

$\mathrm{\ϵ}=\frac{{\mathrm{\ϵ}}^{\′}(T_m^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(7\right)$

In step 5 and step 6, successively with five emissivity ε ' setting value ε ' of infrared thermometer (1) ₁, ε ' ₂, ε ' ₃, ε ' ₄, ε ' ₅With corresponding five measurement temperature value T _m1, T _m2, T _m3, T _m4, T _m5Obtain five material emissivity in substitution formula (7) respectively,

${\mathrm{\ϵ}}_1=\frac{{\mathrm{\ϵ}}_1^{\′}(T_{m1}^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(8a\right)$

${\mathrm{\ϵ}}_2=\frac{{\mathrm{\ϵ}}_2^{\′}(T_{m2}^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(8b\right)$

${\mathrm{\ϵ}}_3=\frac{{\mathrm{\ϵ}}_3^{\′}(T_{m3}^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(8c\right)$

${\mathrm{\ϵ}}_4=\frac{{\mathrm{\ϵ}}_4^{\′}(T_{m4}^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(8d\right)$

${\mathrm{\ϵ}}_5=\frac{{\mathrm{\ϵ}}_5^{\′}(T_{m5}^n-T_e^n)-\frac{g\left(T_e\right)}{C}}{T_r^n-T_e^n}---\left(8e\right)$

To five material emissivity ε obtained above ₁, ε ₂, ε ₃, ε ₄, ε ₅Average and namely obtain the emissivity ε of detected materials in room temperature to 1500 ℃ temperature range and be:

$\mathrm{\ϵ}=\frac{{\mathrm{\ϵ}}_1+{\mathrm{\ϵ}}_2+{\mathrm{\ϵ}}_3+{\mathrm{\ϵ}}_4+{\mathrm{\ϵ}}_5}{5}.---\left(9\right)$

Present embodiment is that the stray radiation energy that calculates in the true temperature, step 1 of the circular test specimen (9) that in circular test specimen (9) measured temperature under five different set emissivity, step 4, thermocouple temperature measurement instrument (7) records according to infrared thermometer (1) in described step 7 calculates the material emissivity ε of circular test specimen (9) in room temperature to 1500 ℃ temperature range.

4. the material emissivity measurement method based on infrared thermometer according to claim 1, is characterized in that, the scope of the experiment measuring temperature described in described step 4 is 373～1773K.

5. the material emissivity measurement method based on infrared thermometer according to claim 2, is characterized in that, when the service band of described infrared thermometer (1) is 3～5 μ m, gets n=9.3.

6. the material emissivity measurement method based on infrared thermometer according to claim 2, is characterized in that, when the service band of described infrared thermometer (1) is 8～14 μ m, gets n=4.

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