A blackbody radiation source cavity emissivity calibration device and calibration method

Abstract

The invention discloses a blackbody radiation source cavity emissivity calibration device and a calibration method. The calibration device comprises a first constant temperature diaphragm, a second constant temperature diaphragm, a first constant temperature water tank, a second constant temperature water tank, a standard radiation thermometer, a digital multimeter, a standard sample, and a blackbody radiation source cavity to be measured. The calibration method comprises the following steps: S1, installing a control pipeline; S2, making the water temperature in the second constant temperature water tank consistent with the temperature of the second constant temperature diaphragm; S3, making the temperature of the first constant temperature diaphragm consistent with the temperature of the first constant temperature water tank; S4, using a standard radiation thermometer to irradiate the standard sample and the blackbody radiation source cavity to be measured respectively, and recording output voltage one and output voltage two; S5, making the temperatures of the first constant temperature diaphragm and the second constant temperature diaphragm consistent with the water temperature in the second constant temperature water tank; S6, repeating step S4, recording output voltage three and output voltage four; S7, calculating the emissivity, and comparing and calibrating it with the previously calibrated emissivity of the blackbody radiation source cavity to be measured.

Description

Technical Field

[0001] The invention relates to the field of blackbody radiation source cavity emissivity detection, and in particular to a blackbody radiation source cavity emissivity calibration device and a calibration method. Background Art

[0002] With the widespread use of infrared thermometers in airports, stations, shopping malls, etc., it is very important to calibrate infrared thermometers on site. In the prior art, a standard blackbody radiation source cavity is usually used to calibrate infrared thermometers. If the emissivity of the standard blackbody radiation source cavity is not accurate, it will lead to deviations in the detection results of the infrared thermometer. Therefore, it is necessary to study a blackbody radiation source cavity emissivity calibration device to solve the above problem. Summary of the invention

[0003] The object of the present invention is to provide a blackbody radiation source cavity emissivity calibration device and calibration method with simple structure and convenient operation in view of the above problems.

[0004] In order to achieve the above object, the technical solution of the present invention is:

[0005] A blackbody radiation source cavity emissivity calibration device comprises a first constant temperature diaphragm, a second constant temperature diaphragm, a first constant temperature water tank, a second constant temperature water tank, a standard radiation thermometer, a digital multimeter, a standard sample with known coating emissivity, and a blackbody radiation source cavity to be measured, wherein the first constant temperature diaphragm and the second constant temperature diaphragm are arranged side by side, light transmission holes are arranged at the center of the first constant temperature diaphragm and the second constant temperature diaphragm, and the axes of the light transmission holes of the first constant temperature diaphragm and the second constant temperature diaphragm coincide with each other, and a first constant temperature diaphragm is arranged inside the first constant temperature diaphragm. The first accommodating cavity is connected to the first constant temperature water tank, the second accommodating cavity is arranged in the second constant temperature aperture and the second accommodating cavity is connected to the second constant temperature water tank; the standard sample and the measured black body radiation source cavity are arranged side by side on the side of the first constant temperature aperture away from the second constant temperature aperture, the standard radiation thermometer is arranged on the side of the second constant temperature aperture away from the first constant temperature aperture, the emission port of the standard radiation thermometer corresponds to the light transmission hole, and the standard radiation thermometer is electrically connected to the digital multimeter.

[0006] Furthermore, the standard sample and the cavity of the blackbody radiation source to be measured are arranged side by side vertically; a lifter is provided at the bottom of the first constant temperature diaphragm, the second constant temperature diaphragm and the standard radiation thermometer; when the lifter rises, the light coming out of the emission port passes through the light-transmitting hole and irradiates the cavity of the blackbody radiation source to be measured; when the lifter descends, the light coming out of the emission port passes through the light-transmitting hole and irradiates the center position of the standard sample.

[0007] Furthermore, the first constant temperature water tank is connected to the first accommodating cavity through a first control pipe, and a first control valve is provided on the first control pipe; the second constant temperature water tank is connected to the second accommodating cavity through a second control pipe, and a second control valve is provided on the second control pipe; the first accommodating cavity is connected to the second accommodating cavity through a third control pipe; and a third control valve is provided on the third control pipe.

[0008] Furthermore, the first control pipeline and the second control pipeline are both circulation pipelines, and water pumps are respectively provided on the first control pipeline and the second control pipeline.

[0009] A calibration method for a blackbody radiation source cavity emissivity calibration device, characterized in that it comprises the following steps:

[0010] S1, installing the first control pipe between the first constant temperature diaphragm and the first constant temperature water tank, the second control pipe between the second constant temperature diaphragm and the second constant temperature water tank, and the third control pipe between the first accommodating cavity and the second accommodating cavity respectively;

[0011] S2, close the third control pipe, connect the second control pipe, and make the water temperature in the second constant temperature water tank and the second constant temperature aperture maintain a constant temperature value;

[0012] S3, controlling the water temperature in the first constant temperature water tank to be maintained between 20°C and 80°C, and the water temperature in the first constant temperature water tank is higher than the water temperature in the second constant temperature water tank; connecting the first control pipe to make the temperature of the first constant temperature aperture consistent with that of the first constant temperature water tank;

[0013] S4. Use a standard radiation thermometer to irradiate the center of the standard sample, and record the output voltage of the standard radiation thermometer in the digital multimeter. Then, operate the lifter to make the standard radiation thermometer irradiate the cavity of the black body radiation source to be measured, and record the output voltage of the standard radiation thermometer in the digital multimeter again.

[0014] S5, closing the first control pipe, connecting the third control pipe, and making the temperature of the first constant temperature diaphragm and the second constant temperature diaphragm consistent with the water temperature in the second constant temperature water tank;

[0015] S6. Use a standard radiation thermometer to irradiate the center of the standard sample, and record the output voltage of the standard radiation thermometer in the digital multimeter. S7. Use the lifter to raise the standard radiation thermometer to irradiate the cavity of the black body radiation source to be measured, and record the output voltage of the standard radiation thermometer in the digital multimeter again.

[0016] S7. The emissivity of the measured blackbody radiation source cavity is obtained by calculation, and the obtained emissivity is compared with the previously calibrated emissivity of the measured blackbody radiation source cavity, thereby achieving a calibration operation on the emissivity of the blackbody radiation source cavity.

[0017] Furthermore, the calculation formula for calculating the cavity emissivity of the blackbody radiation source under test in step S7 is:

[0018]

[0019] in, is the output voltage two; is the output voltage IV; is the output voltage one; is the output voltage three; ρ s is the reflectivity of the standard sample.

[0020] Compared with the prior art, the present invention has the following advantages and positive effects:

[0021] The present invention establishes a set of calibration experimental devices by using standard sheets with known emissivity and devices such as standard radiation thermometers, and performs mathematical model calculations based on the experimental data obtained, thereby obtaining the emissivity of a blackbody radiation source cavity to be measured; by comparing the emissivity with the previously calibrated emissivity of the blackbody radiation source cavity to be measured, the emissivity calibration operation of the blackbody radiation source cavity to be measured can be achieved; and the present invention can use the device to compile calibration specifications, thereby establishing a new measurement standard, which brings convenience to the test operation of the blackbody radiation source emissivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0023] Figure 1 It is a structural schematic diagram of the present invention. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work, any modifications, equivalent substitutions, improvements, etc., should be included in the protection scope of the present invention.

[0025] like Figure 1 As shown, the blackbody radiation source cavity emissivity calibration device in this embodiment includes a first constant temperature diaphragm 7, a second constant temperature diaphragm 8, a first constant temperature water tank 3, a second constant temperature water tank 4, a standard radiation thermometer 1, a digital multimeter 2, a standard sample 6 with known coating emissivity, and a blackbody radiation source cavity 5 to be measured. The first constant temperature diaphragm 7 and the second constant temperature diaphragm 8 are arranged side by side, and the first constant temperature diaphragm 7 and the second constant temperature diaphragm 8 are both provided with a light transmission hole 9 at the center position, and the axes of the light transmission holes 9 of the first constant temperature diaphragm 7 and the second constant temperature diaphragm 8 coincide with each other. A first accommodating cavity is provided and the first accommodating cavity is communicated with the first constant temperature water tank 3, a second accommodating cavity is provided in the second constant temperature aperture 8 and the second accommodating cavity is communicated with the second constant temperature water tank 4; the standard sample 6 and the measured black body radiation source cavity 5 are arranged side by side on the side of the first constant temperature aperture 7 away from the second constant temperature aperture 8, the standard radiation thermometer 1 is arranged on the side of the second constant temperature aperture 8 away from the first constant temperature aperture 7, the emission port of the standard radiation thermometer 1 corresponds to the light transmission hole 9, and the standard radiation thermometer 1 is electrically connected to the digital multimeter 2.

[0026] The standard sample 6 and the measured black body radiation source cavity 5 are arranged side by side vertically; the first constant temperature diaphragm 7, the second constant temperature diaphragm 8 and the bottom end of the standard radiation thermometer 1 are provided with a lifter; when the lifter rises, the light coming out of the emission port passes through the light transmission hole 9 and irradiates the measured black body radiation source cavity 5; when the lifter descends, the light coming out of the emission port passes through the light transmission hole 9 and irradiates the center position of the standard sample 6.

[0027] The first constant temperature water tank 3 is connected with the first accommodating cavity through a first control pipe, and a first control valve is arranged on the first control pipe; the second constant temperature water tank 4 is connected with the second accommodating cavity through a second control pipe, and a second control valve is arranged on the second control pipe; the first accommodating cavity and the second accommodating cavity are connected through a third control pipe; a third control valve is arranged on the third control pipe; the first control pipe and the second control pipe are both circulation pipes, and water pumps are arranged on the first control pipe and the second control pipe respectively.

[0028] The calibration process of the blackbody radiation source cavity emissivity calibration device in this embodiment is as follows:

[0029] S1, installing the first control pipe between the first constant temperature diaphragm and the first constant temperature water tank, the second control pipe between the second constant temperature diaphragm and the second constant temperature water tank, and the third control pipe between the first accommodating cavity and the second accommodating cavity respectively;

[0030] S2, close the third control pipe, connect the second control pipe, and keep the water temperature in the second constant temperature water tank and the temperature of the second constant temperature aperture at 20°C;

[0031] S3, controlling the water temperature in the first constant temperature water tank to be maintained at 30° C.; connecting the first control pipe to make the temperature of the first constant temperature aperture consistent with that of the first constant temperature water tank;

[0032] S4. Use a standard radiation thermometer to irradiate the center of the standard sample, and record the output voltage of the standard radiation thermometer in the digital multimeter. Then, operate the lifter to make the standard radiation thermometer irradiate the cavity of the black body radiation source to be measured, and record the output voltage of the standard radiation thermometer in the digital multimeter again.

[0033] S5, close the first control pipe, connect the third control pipe, and make the temperature of the first constant temperature diaphragm and the second constant temperature diaphragm consistent with the water temperature in the second constant temperature water tank, both of which are 20°C;

[0034] S6. Use a standard radiation thermometer to irradiate the center of the standard sample, and record the output voltage of the standard radiation thermometer in the digital multimeter. S7. Use the lifter to raise the standard radiation thermometer to irradiate the cavity of the black body radiation source to be measured, and record the output voltage of the standard radiation thermometer in the digital multimeter again.

[0035] S7. The emissivity of the cavity of the black body radiation source under test is obtained by calculation; the calculation formula is:

[0036]

[0037] in, is the second output voltage, i.e., the output voltage of the measured black body radiation source cavity when the temperature of the first constant temperature aperture is higher than the temperature of the second constant temperature aperture; is the output voltage four, i.e., the output voltage of the measured black body radiation source cavity when the temperature of the first constant temperature aperture and the second constant temperature aperture are the same; is output voltage 1, i.e., the output voltage of the standard sample when the temperature of the first thermostatic diaphragm is higher than the temperature of the second thermostatic diaphragm; is the output voltage three, that is, the output voltage of the standard sample when the temperature of the first thermostatic diaphragm and the second thermostatic diaphragm is the same; ε c is the emissivity of the blackbody radiation source cavity under test; ρ c is the reflectivity of the cavity of the blackbody radiation source being measured; ρ s is the reflectivity of the standard sample;

[0038] For the standard sample, when the first thermostatic diaphragm and the second thermostatic diaphragm have the same temperature,

[0039]

[0040] When the temperature of A2 is constant at 20℃, and the temperature of A1 is changed between 20℃ and 80℃, then

[0041]

[0042] From (1) and (2), we can get

[0043]

[0044] Where: Ta is the ambient temperature; L(Ta) is the radiant brightness at ambient temperature; εs is the effective emissivity of the standard sample; ρs is the reflectivity of the standard sample; L(T 1-l ) is the first thermostatic aperture at temperature T 1-l LS(T1-l) is the radiant brightness of the standard sample at T 1-l The radiant brightness at temperature; T 1-l is the temperature of the first thermostatic diaphragm when the first thermostatic diaphragm and the second thermostatic diaphragm have the same temperature; L(T 1-h ) is the first thermostatic aperture at temperature T 1-h LS(T1-h) is the radiant brightness of the standard sample at T 1-h The radiant brightness at temperature; T 1-h is the temperature of the first thermostatic diaphragm when the first thermostatic diaphragm and the second thermostatic diaphragm have different temperatures;

[0045] S8. Compare the obtained measured blackbody radiation source cavity emissivity with the previously calibrated emissivity of the measured blackbody radiation source cavity, thereby achieving a calibration operation on the blackbody radiation source cavity emissivity.

[0046] The present invention establishes a set of calibration experimental devices by using standard sheets with known emissivity and devices such as standard radiation thermometers, and performs mathematical model calculations based on the experimental data obtained, thereby obtaining the emissivity of a blackbody radiation source cavity to be measured; by comparing the emissivity with the previously calibrated emissivity of the blackbody radiation source cavity to be measured, the emissivity calibration operation of the blackbody radiation source cavity to be measured can be achieved; and the present invention can use the device to compile calibration specifications, thereby establishing a new measurement standard, which brings convenience to the test operation of the blackbody radiation source emissivity.

Claims

1. A calibration method for a blackbody radiation source cavity emissivity calibration device, characterized in that: The blackbody radiation source cavity emissivity calibration device comprises a first constant temperature diaphragm, a second constant temperature diaphragm, a first constant temperature water bath, a second constant temperature water bath, a standard radiation thermometer, a digital multimeter, a standard sample with known coating emissivity, and a blackbody radiation source cavity to be measured. The first constant temperature diaphragm and the second constant temperature diaphragm are arranged side by side, and light transmission holes are arranged at the center positions of the first constant temperature diaphragm and the second constant temperature diaphragm, and the axes of the light transmission holes of the first constant temperature diaphragm and the second constant temperature diaphragm coincide with each other. A first accommodating cavity is arranged in the first constant temperature diaphragm, and the first accommodating cavity is connected to the first constant temperature water bath. A second accommodating cavity is arranged in the second constant temperature diaphragm, and the second accommodating cavity is connected to the second constant temperature water bath. The standard sample and the blackbody radiation source cavity to be measured are arranged side by side on the side of the first constant temperature diaphragm away from the second constant temperature diaphragm, and the standard radiation thermometer is arranged on the side of the second constant temperature diaphragm away from the first constant temperature diaphragm. The emission port of the standard radiation thermometer corresponds to the light transmission hole. The standard radiation thermometer The standard sample and the cavity of the black body radiation source to be measured are arranged side by side in the longitudinal direction; the first constant temperature aperture, the second constant temperature aperture and the bottom of the standard radiation thermometer are provided with a lifter; when the lifter rises, the light from the emission port passes through the light-transmitting hole and irradiates the cavity of the black body radiation source to be measured; when the lifter descends, the light from the emission port passes through the light-transmitting hole and irradiates the center position of the standard sample; the first constant temperature water tank is connected to the first accommodating cavity through the first control pipe, and the first control pipe is provided with a first control valve; the second constant temperature water tank is connected to the second accommodating cavity through the second control pipe, and the second control pipe is provided with a second control valve; the first accommodating cavity and the second accommodating cavity are connected through a third control pipe; the third control pipe is provided with a third control valve; the first control pipe and the second control pipe are both circulation pipes, and the first control pipe and the second control pipe are respectively provided with water pumps; The calibration method of the blackbody radiation source cavity emissivity calibration device comprises the following steps: S1, installing the first control pipe between the first constant temperature diaphragm and the first constant temperature water tank, the second control pipe between the second constant temperature diaphragm and the second constant temperature water tank, and the third control pipe between the first accommodating cavity and the second accommodating cavity respectively; S2, close the third control pipe, connect the second control pipe, and make the water temperature in the second constant temperature water tank and the second constant temperature aperture maintain a constant temperature value; S3, controlling the water temperature in the first constant temperature water tank to be maintained between 20°C and 80°C, and the water temperature in the first constant temperature water tank is higher than the water temperature in the second constant temperature water tank; connecting the first control pipe to make the temperature of the first constant temperature aperture consistent with that of the first constant temperature water tank; S4. Use a standard radiation thermometer to irradiate the center of the standard sample, and record the output voltage of the standard radiation thermometer in the digital multimeter. Then, operate the lifter to make the standard radiation thermometer irradiate the cavity of the black body radiation source to be measured, and record the output voltage of the standard radiation thermometer in the digital multimeter again. S5, closing the first control pipe, connecting the third control pipe, and making the temperature of the first constant temperature diaphragm and the second constant temperature diaphragm consistent with the water temperature in the second constant temperature water tank; S6. Use a standard radiation thermometer to irradiate the center of the standard sample, and record the output voltage of the standard radiation thermometer in the digital multimeter. S7. Use the lifter to raise the standard radiation thermometer to irradiate the cavity of the black body radiation source to be measured, and record the output voltage of the standard radiation thermometer in the digital multimeter again. S7. The emissivity of the measured blackbody radiation source cavity is obtained by calculation, and the obtained emissivity is compared with the previously calibrated emissivity of the measured blackbody radiation source cavity, thereby achieving a calibration operation on the emissivity of the blackbody radiation source cavity.

2. The calibration method of the blackbody radiation source cavity emissivity calibration device according to claim 1, characterized in that: The calculation formula for calculating the cavity emissivity of the black body radiation source under test in step S7 is: in, is the output voltage two; is the output voltage four; is the output voltage one; is the output voltage three; ρ s is the reflectivity of the standard sample, ε c is the emissivity of the blackbody radiation source cavity under test; ρ c is the reflectivity of the cavity of the blackbody radiation source being measured.

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