Film heat flow meter calibration device

Abstract

The invention discloses a film heat flow meter calibration device, and relates to the technical field of heat flow meter calibration, the film heat flow meter calibration device comprises a heating module located at one side of a uniform temperature module, a first end of a thermal protection module is installed on the uniform temperature module, a second end of the thermal protection module extends in a direction away from the uniform temperature module, and one side of a heat dissipation module is used for placing a calibration plate. The calibration plate is used for placing a heat flow meter to be measured, the thermal protection module comprises a temperature equalizing block, a temperature equalizing rod and a plurality of thermal protection elements, the temperature equalizing block is installed in the temperature equalizing module, the plurality of thermal protection elements are arranged around the periphery of the temperature equalizing rod, and the first end of the temperature equalizing rod and the first ends of the plurality of thermal protection elements are inserted into the temperature equalizing block; the temperature equalizing rod and the thermal protection element are made of the same material, one side, far away from the heat dissipation module, of the to-be-tested heat flow meter is used for contacting with the second end of the temperature equalizing rod, and the second end of the temperature equalizing rod can be completely attached to the to-be-tested heat flow meter. According to the invention, one-dimensional uniform heat flow can be generated at the to-be-measured heat flow meter.

Description

Technical Field

[0001] The invention relates to the technical field of heat flow meter calibration, and in particular to a thin film heat flow meter calibration device. Background Art

[0002] Thin film heat flow meter, that is, an extremely thin heat flow meter with a thickness of usually about ten to twenty microns, consists of a sensitive layer and a thermal resistance layer. It uses one-dimensional Fourier's law to calculate the heat flux through the surface of the heat flow meter. It has the advantages of small size, easy installation, and fast response rate.

[0003] The calibration methods of heat flow meters are mainly divided into three types according to the way the heat flux is generated: the calibration method of thermal conductivity heat flow meter, the calibration method of convection heat flow meter and the calibration method of radiation heat flow meter. Common thermal conductivity heat flow calibration devices are mainly divided into two types: relative calibration and absolute calibration.

[0004] Among them, the relative calibration device consists of a main heating plate, a standard heat flux sensor, a heat flux sensor to be tested, a cold plate, and surrounding thermal protection components. During operation, the heat flux is generated by the main heating plate, passes through the standard heat flux meter and the heat flux meter to be tested in turn, and the heat flux meter to be tested is calibrated by the standard heat flux meter. However, this method is limited by the structure and performance parameters of the standard heat flux meter (standard plate) and is often used for the calibration of low-temperature and small heat fluxes, such as the test of the thermal insulation performance of the thermal enclosure structure of a building; the absolute calibration device does not include a standard heat flux meter, but theoretically calculates the heat flux by calculating the electric power of the heating plate. This type of calibration device is limited by the experimental conditions and the level of thermal insulation protection, and it is usually difficult to achieve high-precision calibration at high temperatures.

[0005] At the same time, for the thin film heat flux meter, the sensitive layer material and the thermal resistance layer material are sputtered onto the alumina substrate through a coating process, wherein the thermal resistance layer thickness is 20μm, and the sensitive layer sensing area is 4mm*4mm. Due to the existence of the thin film, the surface of the heat flux meter is not a complete plane, but has tiny protrusions, which leads to the fact that the hot plate and the substrate cannot be completely fitted during calibration, and a certain air layer is formed. The simulation calculation results show that the uniform heat flow through the hot plate appears uneven in the air layer and the upper surface of the film. This is mainly due to the large thermal resistance at the air interlayer and the difficulty in heat transfer. Therefore, the heat flow at the film is much larger than that at the air layer, and the heat flow distribution on the film shows a trend from the edge to the middle. This is because the heat on the upper part of the air layer outside the film cannot be transferred from the air side, thus generating lateral heat conduction, so that the peripheral heat is transferred from the edge of the film. Therefore, for the calibration of the thin film heat flux meter, the conventional thermal conductivity calibration device can no longer meet the one-dimensional uniformity assumption. The heat flow through the heat flux meter is different from that through the substrate and the cold plate, and its size cannot be measured, resulting in the failure of the calibration device. Summary of the invention

[0006] The object of the present invention is to provide a thin film heat flow meter calibration device to solve the problems existing in the above-mentioned prior art and to generate a one-dimensional uniform heat flow at the heat flow meter to be measured.

[0007] To achieve the above object, the present invention provides the following solutions:

[0008] The present invention provides a thin film heat flux meter calibration device, comprising a heating module, a temperature equalizing module, a heat dissipation module and a thermal protection module, wherein the heating module is located at one side of the temperature equalizing module, a first end of the heat protection module is installed on the temperature equalizing module, and a second end of the heat protection module extends in a direction away from the temperature equalizing module, one side of the heat dissipation module is used for placing a calibration plate, and the calibration plate is used for placing a heat flux meter to be measured, the thermal protection module comprises a temperature equalizing block, a temperature equalizing rod and a plurality of heat protection elements, the temperature equalizing block is installed in the temperature equalizing module, a plurality of the heat protection elements are arranged around the periphery of the temperature equalizing rod, and a first end of the temperature equalizing rod and a plurality of first ends of the heat protection elements are both inserted into the temperature equalizing block, the temperature equalizing rod and the heat protection element are made of the same material, the heat flux meter to be measured is used for contacting the second end of the temperature equalizing rod on a side away from the heat dissipation module, and the second end of the temperature equalizing rod can be completely fitted with the heat flux meter to be measured.

[0009] In one embodiment, the heating module is a heating plate.

[0010] In one embodiment, the heating plate includes a tungsten wire and a ceramic matrix, the tungsten wire is embedded in the ceramic matrix, and the ceramic matrix is ​​made of silicon nitride ceramic material.

[0011] In one embodiment, the temperature equalizing module is a temperature equalizing plate, one side of which is used to contact the heating module, a through hole is provided in the middle of the temperature equalizing plate, the temperature equalizing block is installed in the through hole, and an installation hole is also provided on the temperature equalizing plate, and the installation hole is used to install a thermocouple.

[0012] In one embodiment, the temperature homogenizing plate is made of nickel material.

[0013] In one embodiment, a plurality of temperature balancing grooves are provided on one side of the temperature balancing block, and the first end of the temperature balancing rod and the first end of each of the heat protection elements are respectively inserted into the corresponding temperature balancing grooves, and there is a spacing between the temperature balancing rod and each of the heat protection elements, and between adjacent heat protection elements.

[0014] In one embodiment, the thermal protection element is a thermal protection rod, the lengths of the thermal protection rods are the same, and the lengths of the thermal protection rods are greater than the lengths of the temperature-averaging rods, the second ends of the thermal protection rods protrude from the second end of the temperature-averaging rods, and the thermal protection rods are provided with temperature difference thermocouples, which are arranged along the length direction of the thermal protection rods.

[0015] In one embodiment, the temperature-averaging rod and the heat protection rod are both made of chrome steel, and the calibration plate is made of alumina.

[0016] In one embodiment, the size of the temperature-averaging rod is 4mm*4mm*25mm; the size of the heat flux meter to be tested is 4mm*4mm*0.6mm; and the size of the calibration plate is 8mm*8mm*1.4mm.

[0017] In one embodiment, the heat dissipation module includes a heat dissipation seat and a heat dissipation protrusion, the heat dissipation protrusion is fixed to one side of the middle part of the heat dissipation seat, the side of the heat dissipation protrusion away from the heat dissipation seat is used to contact the calibration plate, and the side of the heat dissipation seat away from the heat dissipation protrusion is used to be set toward the air outlet of the air compressor.

[0018] Compared with the prior art, the present invention has achieved the following technical effects:

[0019] The present invention provides a thin film heat flux meter calibration device, wherein the heating module is located on one side of the temperature equalizing module, so as to provide a heat source through the heating module and realize heat transfer through the temperature equalizing module, the first end of the thermal protection module is installed on the temperature equalizing module, the second end of the thermal protection module extends in a direction away from the temperature equalizing module, one side of the heat dissipation module is used to place a calibration plate, the calibration plate is used to place a heat flux meter to be measured, and the heat dissipation function is achieved through the heat dissipation module, the thermal protection module comprises a temperature equalizing block, a temperature equalizing rod and a plurality of thermal protection elements, the temperature equalizing rod is used to transfer a calibration heat flux to the heat flux meter to be measured, the temperature equalizing block is installed in the temperature equalizing module, the plurality of thermal protection elements are arranged around the periphery of the temperature equalizing rod, and the first end of the temperature equalizing rod and the first ends of the plurality of thermal protection elements are all inserted into the temperature equalizing block, the circumferentially arranged thermal protection elements can provide a temperature that is completely consistent with the temperature equalizing rod, and at the same time due to The heat source is the same as that of the temperature-averaging rod, so the overall temperature gradient tends to be similar. At this time, the temperature difference between the thermal protection element and the temperature-averaging rod at the same horizontal position is extremely small. The heat flux meter to be tested is used to contact the second end of the temperature-averaging rod on the side away from the heat dissipation module. The second end of the temperature-averaging rod can be completely fitted with the heat flux meter to be tested, thereby eliminating the influence of the air layer caused by the protrusion. At the same time, the thermal protection elements on all sides are completely consistent with the material of the temperature-averaging rod, so that the thermal protection elements will produce the same temperature gradient as the temperature-averaging rod, and the thermal insulation effect is optimal, so that a one-dimensional uniform heat flow can be generated at the heat flux meter to be tested. In addition, through the above design, when calibrating, since the thermal conductivity of the temperature-averaging rod is known, the heat flux density flowing through the temperature-averaging rod and the heat flux meter to be tested is the same, so the heat flux density flowing through the heat flux meter to be tested can be calculated through the temperature difference in the temperature-averaging rod and calibrated. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] 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 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 work.

[0021] Figure 1 It is a structural schematic diagram of the thin film heat flow meter calibration device in the present invention;

[0022] Figure 2 It is a schematic diagram of the structure of the heat dissipation module and the heat protection module in the present invention;

[0023] Figure 3 It is a structural schematic diagram of the temperature equalization module in the present invention;

[0024] Figure 4 It is a schematic diagram of the structure of the heat dissipation module, the heat flux meter to be tested and the calibration plate in the present invention;

[0025] Figure 5 It is a structural schematic diagram of the thermal protection module in the present invention;

[0026] Figure 6 It is a schematic diagram of the structure of the temperature equalizing block in the present invention;

[0027] In the figure: 1-heating module, 2-temperature equalizing module, 3-heat protection rod, 4-heat dissipation module, 5-temperature equalizing block, 6-heat dissipation protrusion, 7-heat dissipation seat, 8-through hole, 9-heat flux meter to be tested, 10-calibration plate, 11-temperature equalizing rod, 12-temperature equalizing tank. DETAILED DESCRIPTION

[0028] 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 are within the scope of protection of the present invention.

[0029] The purpose of the present invention is to provide a thin film heat flow meter calibration device to solve the problems existing in the prior art and enable a one-dimensional uniform heat flow to be generated at the heat flow meter to be measured.

[0030] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] like Figure 1-Figure 6As shown, the present embodiment provides a thin film heat flux meter calibration device, comprising a heating module 1, a temperature equalizing module 2, a heat dissipation module 4 and a thermal protection module, wherein the heating module 1 is located on one side of the temperature equalizing module 2, so as to provide a heat source through the heating module 1 and realize heat transfer through the temperature equalizing module 2, a first end of the heat protection module is mounted on the temperature equalizing module 2, and a second end of the heat protection module extends in a direction away from the temperature equalizing module 2, one side of the heat dissipation module 4 is used for placing a calibration plate 10, and the calibration plate 10 is used for placing a heat flux meter 9 to be measured, and heat dissipation is performed through the heat dissipation module 4, the thermal protection module comprises a temperature equalizing block 5, a temperature equalizing rod 11 and a plurality of heat protection elements, the temperature equalizing rod 11 is used to transfer a calibration heat flux to the heat flux meter 9 to be measured, the temperature equalizing block 5 is mounted in the temperature equalizing module 2, a plurality of heat protection elements are arranged around the periphery of the temperature equalizing rod 11, and the temperature equalizing rod The first end of 11 and the first ends of multiple thermal protection elements are all inserted into the temperature block 5. The circumferentially arranged thermal protection elements can provide a temperature that is completely consistent with the temperature rod 11. At the same time, since the heat source is the same as that of the temperature rod 11, the overall temperature gradient tends to be similar. At this time, the temperature difference between the thermal protection elements and the temperature rod 11 at the same horizontal position is extremely small. The heat flux meter 9 to be tested is used to contact the second end of the temperature rod 11 on the side away from the heat dissipation module 4. The second end of the temperature rod 11 can be completely fitted with the heat flux meter 9 to be tested, thereby eliminating the influence of the air layer caused by the protrusion. At the same time, the thermal protection elements on all sides are completely consistent with the material of the temperature rod 11, so that the thermal protection elements will produce the same temperature gradient as the temperature rod 11, and the thermal insulation effect is optimal, so that a one-dimensional uniform heat flux can be generated at the heat flux meter 9 to be tested, and through the above design. When calibrating the present embodiment, since the thermal conductivity of the temperature-averaging rod 11 is known, the heat flux density flowing through the temperature-averaging rod 11 and the heat flux meter 9 to be measured are the same. Therefore, the heat flux density flowing through the heat flux meter 9 to be measured can be calculated through the temperature difference in the temperature-averaging rod 11 and calibrated. The calibration principle is clear, the structure is simple, the temperature and heat flux are controllable, and the calibration accuracy is high.

[0032] The heating module 1 is a heating plate, which includes a tungsten wire and a ceramic matrix. The tungsten wire is used as a heating source. The tungsten wire is embedded in the ceramic matrix and formed into a whole by hot pressing and sintering. Then, it is ground and welded with leads to form a heating plate. The ceramic matrix is ​​made of silicon nitride ceramic material, so that the surface heat load of the heating plate can reach 250Kw / m 2 , temperature resistant to 1200℃.

[0033] Since the heating plate is designed to be long and narrow, it needs to be used in conjunction with the temperature equalization module 2. The temperature equalization module 2 is a temperature equalization plate. One side of the temperature equalization plate is used to contact the heating module 1. The size of the temperature equalization plate is 6cm*6cm*1cm. A through hole 8 is opened in the middle of the temperature equalization plate. The size of the through hole 8 is 2cm*2cm*0.5cm. The temperature equalization block 5 is installed in the through hole 8. The temperature equalization plate is also provided with a mounting hole to achieve the connection and positioning of the temperature equalization plate. The mounting hole is used to install the thermocouple. A through hole 8 with a diameter of 2mm is drilled in the center of the two sides of the temperature equalization plate to install a K-type thermocouple for temperature measurement.

[0034] The temperature plate is made of nickel material with high thermal conductivity and high temperature resistance.

[0035] A plurality of temperature-averaging grooves 12 are provided on one side of the temperature-averaging block 5. The size of the temperature-averaging block 5 is 2cm*2cm*0.5cm and can be connected to the heating plate. The first end of the temperature-averaging rod 11 and the first end of each thermal protection element are respectively inserted into the corresponding temperature-averaging groove 12. The heat flow passes through the temperature-averaging block 5, the temperature-averaging rod 11 and the heat flux meter 9 to be measured in turn, and there is a spacing between the temperature-averaging rod 11 and each thermal protection element, as well as between adjacent thermal protection elements.

[0036] The thermal protection element is a thermal protection rod 3, the length of each thermal protection rod 3 is the same, and the length of the thermal protection rod 3 is greater than the length of the temperature-averaging rod 11, the second ends of the thermal protection rods 3 protrude from the second end of the temperature-averaging rod 11, and temperature difference thermocouples are arranged on the thermal protection rods 3, and the temperature difference thermocouples are arranged along the length direction of the thermal protection rods 3. As a preferred embodiment, an opening is provided at 8 mm and 23 mm in the length direction of the temperature-averaging rod 11, the aperture of the opening is 1 mm, the depth of the opening is 1 mm, and the temperature difference thermocouples are arranged in the opening.

[0037] The temperature-averaging rod 11 and the heat protection rod 3 are both made of chrome steel (WCr=5%), and the calibration plate 10 is made of alumina.

[0038] The size of the temperature-averaging rod 11 is 4mm*4mm*25mm, the size of the heat protection rod 3 is 4mm*4mm*27mm; the size of the heat flux meter 9 to be tested is 4mm*4mm*0.6mm; the size of the calibration plate 10 is 8mm*8mm*1.4mm.

[0039] The heat dissipation module 4 includes a heat dissipation seat 7 and a heat dissipation protrusion 6. The heat dissipation protrusion 6 is fixed to one side of the middle of the heat dissipation seat 7. The side of the heat dissipation protrusion 6 away from the heat dissipation seat 7 is used to contact the calibration plate 10. The side of the heat dissipation seat 7 away from the heat dissipation protrusion 6 is used to be arranged toward the air outlet of the air compressor, and then the high-speed airflow generated by the air compressor and the air nozzle is used to impact and cool the heat dissipation seat 7 to achieve heat dissipation. The heat dissipation module 4 is made of nickel material, the size of the heat dissipation protrusion 6 is 2cm*2cm*1cm, and the size of the heat dissipation seat 7 is 6cm*6cm*1cm.

[0040] Through the above design, this embodiment can provide 0℃-1000℃, with a maximum of 300KW / m 2 The uniform heat flow has a calibration relative error of <3%, which solves the problem that the thin film bulge introduces an air interlayer during the calibration of the thin film heat flow meter, making the premise of one-dimensional uniform heat flow unsatisfactory and causing the calibration device to fail.

[0041] The basic principle of measuring the heat flux meter 9 to be measured in this embodiment is the one-dimensional Fourier law. When the heat flux passes through the surface of the heat flux meter 9 to be measured, a temperature difference will be generated between the upper and lower surfaces of the thermal resistance layer due to the heat transfer phenomenon. At this time, the temperature difference can be measured in a certain way to calculate the size of the heat flux according to the one-dimensional Fourier law. The heat flux calculation formula is:

[0042]

[0043] Where q is the heat flux through the surface of the heat flux meter 9 to be measured, λ is the thermal conductivity of the thermal resistance layer, δ is the thickness of the thermal resistance layer, T 1 , T 2 are the temperatures of the upper and lower surfaces of the thermal resistance layer, respectively.

[0044] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A thin film heat flow meter calibration device, characterized in that: The heat dissipation module of claim 1, wherein the first end of the heat dissipation module is mounted on the heat dissipation module, the second end of the heat dissipation module is extended in a direction away from the heat dissipation module, and the heat dissipation module is used to place a calibration plate on one side of the heat dissipation module. The calibration plate is used to place a heat flux meter to be tested. The heat protection module comprises a heat dissipation block, a heat dissipation rod and a plurality of heat protection elements. The heat dissipation block is mounted in the heat dissipation module, a plurality of heat protection elements are arranged around the periphery of the heat dissipation rod, and a first end of the heat dissipation rod and a plurality of first ends of the heat protection elements are both inserted into the heat dissipation block. The heat dissipation rod and the heat protection element are made of the same material. The heat flux meter to be tested is used to contact the second end of the temperature dissipation rod on a side away from the heat dissipation module, and the second end of the temperature dissipation rod can be completely fitted with the heat flux meter to be tested.

2. The thin film heat flow meter calibration device according to claim 1, characterized in that: The heating module is a heating plate.

3. The thin film heat flow meter calibration device according to claim 2, characterized in that: The heating plate comprises a tungsten wire and a ceramic matrix, wherein the tungsten wire is embedded in the ceramic matrix, and the ceramic matrix is ​​made of silicon nitride ceramic material.

4. The thin film heat flow meter calibration device according to claim 1, characterized in that: The temperature equalizing module is a temperature equalizing plate, one side of which is used to contact the heating module, a through hole is provided in the middle of the temperature equalizing plate, the temperature equalizing block is installed in the through hole, and an installation hole is also provided on the temperature equalizing plate, and the installation hole is used to install a thermocouple.

5. The thin film heat flow meter calibration device according to claim 4, characterized in that: The temperature balancing plate is made of nickel material.

6. The thin film heat flow meter calibration device according to claim 1, characterized in that: A plurality of temperature balancing grooves are provided on one side of the temperature balancing block, and the first end of the temperature balancing rod and the first end of each heat protection element are respectively inserted into the corresponding temperature balancing grooves, and there is a spacing between the temperature balancing rod and each heat protection element, and between adjacent heat protection elements.

7. The thin film heat flow meter calibration device according to claim 6, characterized in that: The thermal protection elements are thermal protection rods, each of which has the same length and is greater than the length of the temperature-averaging rod. The second ends of the thermal protection rods protrude from the second end of the temperature-averaging rod. The thermal protection rods are provided with temperature difference thermocouples, which are arranged along the length direction of the thermal protection rods.

8. The thin film heat flow meter calibration device according to claim 7, characterized in that: The temperature-averaging rod and the heat protection rod are both made of chrome steel, and the calibration plate is made of aluminum oxide.

9. The thin film heat flow meter calibration device according to claim 7, characterized in that: The size of the temperature-averaging rod is 4mm*4mm*25mm; the size of the heat flux meter to be tested is 4mm*4mm*0.6mm; the size of the calibration plate is 8mm*8mm*1.4mm.

10. The thin film heat flow meter calibration device according to claim 1, characterized in that: The heat dissipation module includes a heat dissipation seat and a heat dissipation protrusion, the heat dissipation protrusion is fixed to one side of the middle part of the heat dissipation seat, the side of the heat dissipation protrusion away from the heat dissipation seat is used to contact the calibration plate, and the side of the heat dissipation seat away from the heat dissipation protrusion is used to be set toward the air outlet of the air compressor.

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