CN111220652A - High-temperature heat conductivity coefficient measuring device based on protection hot plate method - Google Patents
High-temperature heat conductivity coefficient measuring device based on protection hot plate method Download PDFInfo
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- G01N25/20—Investigating or analyzing materials by the use of thermal means by investigating the development of heat, i.e. calorimetry, e.g. by measuring specific heat, by measuring thermal conductivity
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Abstract
The invention discloses a high-temperature heat conductivity coefficient measuring device based on a protected hot plate method, and belongs to the field of material thermophysical property testing. The invention mainly comprises a core testing system, a vacuum pumping system, a control system and an acquisition system. The core testing system adopts a symmetrical structure of round double samples and alternate cold and hot plates. The whole measuring device is of a circular structure which is symmetrical up and down, and comprises an upper heat insulation layer, a lower heat insulation layer, an upper cold plate, a lower cold plate, a sample to be measured and a central hot plate unit from outside to inside, wherein the central hot plate unit comprises a central hot plate and a heat protection ring; the periphery is provided with an edge protection structure, a peripheral heat insulation layer and a multilayer radiation-proof screen; each heating unit is provided with a thermocouple for measuring temperature. The high-temperature heat conductivity coefficient measurement is realized based on a protective hot plate method, the measurement precision is improved by controlling the temperature uniformity of a cold plate and a hot plate during the test, the temperature measurement range is remarkably widened by using a high-reflectivity radiation-proof screen and an edge protection structure and selecting a proper temperature sensor, and the upper limit of the temperature measurement can reach 1000K.
Description
Technical Field
The invention belongs to the field of material thermophysical property testing, particularly relates to a high-temperature heat conductivity coefficient measuring device, and particularly relates to a high-temperature heat conductivity coefficient measuring device based on a protection hot plate method.
Background
The thermal conductivity coefficient is an important index for representing the thermal conductivity of a substance, is an important parameter for measuring the thermophysical performance of the material, and has important significance for determining the thermal conductivity coefficient of the material at different temperatures in the national defense and military fields of aviation, aerospace, weapons, ships and the like, civil buildings, fire fighting and the like. The measurement method of the thermal conductivity can be mainly divided into a steady-state method and an unsteady-state method, wherein the steady-state method means that the temperature distribution in a test piece is a steady-state temperature field which does not change along with time, and when the test piece reaches thermal equilibrium, the thermal conductivity of the test piece can be directly measured by measuring the heat flow rate and the temperature gradient of the unit area of the test piece, and the measurement method mainly comprises a protective hot plate method, a heat flow method and the like. The protective hot plate method is a method which is recognized at home and abroad at present and has the highest measurement accuracy, and can be used for calibrating reference samples and calibrating other instruments.
At present, the measurement precision of a material thermal conductivity coefficient measuring device based on a protection hot plate method designed by domestic and foreign companies and research institutions is very high, and the temperature range is wide, but because a platinum resistance temperature sensor is generally used as a temperature control and measurement device, the maximum test temperature can only reach 600 ℃, and the measurement of the material thermal conductivity coefficient at higher temperature cannot be realized.
Disclosure of Invention
The invention discloses a high-temperature heat conductivity coefficient measuring device based on a protected hot plate method, which aims to solve the technical problems that: the high-temperature heat conductivity coefficient measurement is realized based on a protection hot plate method, the measurement precision is improved by controlling the temperature uniformity of a cold plate and a hot plate during the test, the temperature measurement range is remarkably widened by a high-reflectivity radiation-proof screen and an edge protection structure and selecting a proper temperature sensor, and the upper limit of the temperature measurement can reach 1000K.
The invention is realized by the following technical scheme.
The invention discloses a high-temperature heat conductivity coefficient measuring device based on a protected hot plate method. The core testing system adopts a symmetrical structure of round double samples and alternate cold and hot plates. The whole measuring device is of a circular structure which is symmetrical up and down, and comprises an upper heat insulation layer, a lower heat insulation layer, an upper cold plate, a lower cold plate, a sample to be measured and a central hot plate unit from outside to inside, wherein the central hot plate unit comprises a central hot plate and a heat protection ring; the periphery is provided with an edge protection structure, a peripheral heat insulation layer and a multilayer radiation-proof screen, and the edge protection structure, the peripheral heat insulation layer and the multilayer radiation-proof screen are used for heat preservation, heat insulation and radiation protection of the testing device; each heating unit is provided with a thermocouple for measuring temperature.
The principle of measuring the temperature difference by the thermopile is that the positive electrode and the negative electrode of the thermocouple of two adjacent test points are reversely connected and serially connected, every two adjacent test points form a pair, the temperature difference of the two test points of the central hot plate and the thermal protection ring is measured to form X pairs of temperature differences together, and finally the algebraic sum of all the X pairs of temperature differences is output. Thus, the thermopile is used to measure the temperature difference between the central hot plate and the heat protection ring.
In order to reduce the cost and the complexity of the manufacturing process, preferably, the thermocouple is an N-type thermocouple; the thermopile is an N-type thermopile.
Preferably, a temperature control unit is arranged in the peripheral heat insulation layer, and the temperature of the temperature control unit is controlled to be slightly lower than the test temperature during testing so as to perform environmental heat compensation. The slightly lower amplitude of the slightly lower test temperature depends on the environment heat supplementing requirement.
Preferably, the upper cold plate, the lower cold plate, the central hot plate and the heat protection ring heating wires are arranged in a ring shape, Y N-type thermocouples are used for monitoring the temperatures of the cold and hot plates at different positions simultaneously, and the temperature uniformity of the cold and hot plates during testing is effectively controlled.
More preferably, 5N-type thermocouples are used to simultaneously monitor the temperature of the cold and hot plates at different positions.
Preferably, the multilayer radiation-proof screen is made of high-reflectivity mirror stainless steel, energy loss caused by radiation heat dissipation can be effectively reduced, the heat compensation function of the edge heating protection structure is combined, the N-type thermocouple is selected as the expanded temperature measurement range of the temperature measurement sensor, and the upper limit of the heat conductivity coefficient and the temperature measurement of the whole set of device can reach 1000K.
The invention discloses a working method of a high-temperature heat conductivity coefficient measuring device based on a protective hot plate method, which comprises the following steps:
the first step is as follows: the upper cold plate and the central hot plate unit are sequentially lifted up through the control system, so that the upper cold plate and the central hot plate unit are separated, and the central hot plate unit and the lower cold plate are separated, and the tested sample is conveniently installed;
the second step is that: respectively installing two tested samples with the same diameter between an upper cold plate and a central hot plate unit and between the central hot plate unit and a lower cold plate;
the third step: checking the acquisition system to determine that each temperature sensor is correctly connected;
the fourth step: the central hot plate unit and the upper cold plate are sequentially dropped through the control system, the tested samples are compressed by the aid of self gravity, and the thicknesses of the two tested samples are measured for calculation;
the fifth step: the vacuum chamber is sealed and vacuumized to ensure that the system is in a vacuum state;
and a sixth step: the testing system is started, the central hot plate unit, the upper cold plate and the lower cold plate are controlled to be heated to the testing temperature respectively, when the temperature sensor displays stably, and after the temperature uniformity of the central hot plate unit, the upper cold plate and the lower cold plate meets requirements, the heat conductivity coefficient of a tested sample is obtained through testing calculation, an N-type thermopile structure temperature difference testing method, an edge heating protection structure and a high-reflectivity radiation protection screen are adopted, the testing system meets a one-dimensional heat conduction model, the influence of environmental factors on a testing result can be effectively reduced, and the measuring precision is improved.
Has the advantages that:
1. according to the high-temperature heat conductivity coefficient measuring device based on the protected hot plate method, the temperature difference testing method of the N-type thermopile structure, the edge heating protection structure and the high-reflectivity radiation-proof screen are adopted, so that the testing system meets a one-dimensional heat conduction model, the influence of environmental factors on a testing result can be effectively reduced, and the measuring precision is improved.
2. According to the high-temperature heat conductivity coefficient measuring device based on the hot plate protection method, the heating wires of the cold and hot plates are in an annular layout mode, a plurality of N-type thermocouples are used for monitoring the temperatures of the cold and hot plates at different positions at the same time, the uniformity of the temperature of the cold and hot plates during testing can be effectively controlled, and the measuring precision is further improved.
3. According to the high-temperature thermal conductivity coefficient measuring device based on the protective hot plate method, the radiation energy loss is effectively reduced by using high-reflectivity mirror surface stainless steel, the heat compensation function of the edge heating protection structure is combined, an N-type thermocouple is selected as the expanded temperature measuring range of the temperature measuring sensor, and the upper limit of the thermal conductivity coefficient temperature measurement of the whole device can reach 1000K.
Drawings
FIG. 1 is a schematic diagram of a heating wire layout of a cold and hot plate of a high-temperature thermal conductivity measuring device based on a protected hot plate method.
FIG. 2 is a schematic diagram of an N-type thermopile of a central heating plate unit of a high-temperature thermal conductivity measuring device based on a protective hot plate method.
FIG. 3 is a schematic structural diagram of a high-temperature thermal conductivity measuring device based on a protected hot plate method.
Wherein: 1-upper and lower heat insulation layers, 2-edge protection structure, 3-lower cold plate, 4-peripheral heat insulation layer, 5-radiation protection screen, 6-heat protection ring, 7-central hot plate, 8-sample to be tested, 9-N type thermocouple, 10-upper cold plate, 11-displacement sensor, 12-vacuum pumping system, 13-heating wire and 14-thermopile.
Detailed Description
For a better understanding of the objects and advantages of the present invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings and examples.
Example 1:
as shown in fig. 3, the high-temperature thermal conductivity measurement device based on the protected hot plate method disclosed in this embodiment is composed of a core test system, a vacuum pumping system, a control system and an acquisition system, wherein the core test system adopts a symmetrical structure of round double samples and alternate cold and hot plates. The whole measuring device is of a circular structure which is symmetrical up and down, and comprises an upper heat insulation layer 1, a lower heat insulation layer 10, an upper cold plate 3, a sample to be tested 8 and a central hot plate unit from outside to inside, wherein the central hot plate unit comprises a central hot plate 7 and a heat protection ring 6; the periphery is provided with an edge protection structure 2, a peripheral heat insulation layer 4 and a multilayer radiation-proof screen 5 for heat preservation and heat insulation of the testing device; each heating unit is provided with a thermocouple 9 for measuring temperature.
The working method of the high-temperature heat conductivity coefficient measuring device based on the protection hot plate method disclosed by the embodiment comprises the following steps:
the first step is as follows: the upper cold plate 10 and the central hot plate 7 are sequentially lifted by a control system, so that the upper cold plate 10 is separated from the central hot plate 7, and the central hot plate 7 is separated from the lower cold plate 3, and the test sample is conveniently installed;
the second step is that: two tested samples with the diameter of 300mm are respectively arranged between the upper cold plate 10 and the central hot plate 7 unit, and between the central hot plate 7 unit and the lower cold plate 3;
the third step: checking the acquisition system to determine that each temperature sensor is correctly connected;
the fourth step: the central hot plate 7 unit and the upper cold plate 10 are sequentially dropped through a control system, the tested samples are tightly pressed by means of self gravity, and the thickness of the two tested samples is measured for calculation;
the fifth step: the vacuum chamber is sealed and evacuated to 10 by an evacuation system 12-1Pa；
And a sixth step: and a sixth step: the testing system is started, the central hot plate unit, the upper cold plate 10 and the lower cold plate 3 are controlled to be heated to testing temperatures respectively, when the temperature sensor displays stability, and the temperature uniformity of the central hot plate unit, the upper cold plate 10 and the lower cold plate 3 is smaller than 0.4 ℃, the heat conductivity coefficient of a tested sample is obtained through testing calculation, and an N-type thermopile structure temperature difference testing method, an edge heating protection structure and a high-reflectivity radiation protection screen are adopted, so that the testing system meets a one-dimensional heat conduction model, the influence of environmental factors on a testing result can be effectively reduced, and the measuring precision is improved.
The above detailed description is intended to illustrate the objects, aspects and advantages of the present invention, and it should be understood that the above detailed description is only exemplary of the present invention and is not intended to limit the scope of the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (7)
1. The utility model provides a high temperature coefficient of heat conductivity measuring device based on protection hot plate method which characterized in that: the device mainly comprises a core testing system, a vacuumizing system, a control system and an acquisition system; the core test system adopts a symmetrical structure of round double samples and alternate cold and hot plates; the whole measuring device is of a circular structure which is symmetrical up and down, and comprises an upper heat insulation layer (1), a lower cold plate (10), a lower cold plate (3), a measured sample (8) and a central hot plate unit from outside to inside, wherein the central hot plate unit comprises a central hot plate (7) and a heat protection ring (6); the periphery is provided with an edge protection structure (2), a peripheral heat insulation layer (4) and a multilayer radiation protection screen (5) for heat preservation, heat insulation and radiation protection of the testing device; each heating unit is provided with a thermocouple (9) for measuring temperature;
the principle of measuring the temperature difference by the thermopile (14) is that the positive and negative electrodes of the thermocouples (9) of two adjacent test points are reversely connected in series, every two adjacent test points are in a pair, the temperature difference of the two test points of the central hot plate (7) and the heat protection ring (6) is measured, X pairs of temperature differences are formed by the test points, and finally, the algebraic sum of all X pairs of temperature differences is output; therefore, the thermopile is used for measuring the temperature difference of the central hot plate (7) and the heat protection ring (6).
2. The high-temperature thermal conductivity measuring device based on the guarded hot plate method as claimed in claim 1, wherein: in order to reduce the cost and the complexity of the manufacturing process, the thermocouple (9) is an N-type thermocouple; the thermopile (14) is selected from an N-type thermopile.
3. The high-temperature thermal conductivity measuring device based on the guarded hot plate method as claimed in claim 2, wherein: a temperature control unit is arranged in the peripheral heat insulation layer (4), and the temperature of the temperature control unit is controlled to be slightly lower than the test temperature during test so as to carry out environmental heat compensation; the slightly lower amplitude of the slightly lower test temperature depends on the environment heat supplementing requirement.
4. The high-temperature thermal conductivity measuring device based on the guarded hot plate method as claimed in claim 3, wherein: the heating wires of the upper cooling plate (10), the lower cooling plate (3), the central heating plate (7) and the heat protection ring (6) adopt an annular layout mode, Y N-type thermocouples are used for monitoring the temperatures of different positions of the cooling and heating plates at the same time, and the temperature uniformity performance of the cooling and heating plates during testing is effectively controlled.
5. The high-temperature thermal conductivity measuring device based on the guarded hot plate method as claimed in claim 4, wherein: each using 5N-type thermocouples to monitor the temperature of the cold and hot plates simultaneously at different locations.
6. The high-temperature thermal conductivity measuring device based on the guarded hot plate method as claimed in claim 5, wherein: the multilayer radiation-proof screen (5) is made of high-reflectivity mirror surface stainless steel, energy loss caused by radiation heat dissipation can be effectively reduced, the heat supplementing function of the edge heating protection structure is combined, an N-type thermocouple is selected as the expanded temperature measurement range of the temperature measurement sensor, and the upper limit of the heat conductivity coefficient and the temperature measurement of the whole set of device can reach 1000K.
7. The high-temperature thermal conductivity measuring device based on the guarded hot plate method as claimed in claim 6, wherein: the working method comprises the following steps of,
the first step is as follows: the upper cold plate (10) and the central hot plate unit are sequentially lifted through the control system, so that the upper cold plate (10) is separated from the central hot plate unit, and the central hot plate unit is separated from the lower cold plate (3), and a tested sample is conveniently installed;
the second step is that: two tested samples with the same diameter are respectively arranged between an upper cold plate (10) and a central hot plate unit, and between the central hot plate unit and a lower cold plate (3);
the third step: checking the acquisition system to determine that each temperature sensor is correctly connected;
the fourth step: the central hot plate unit and the upper cold plate (10) are sequentially dropped through a control system, the tested samples are compressed by the aid of self gravity, and the thicknesses of the two tested samples are measured for calculation;
the fifth step: the vacuum chamber is sealed and vacuumized to ensure that the system is in a vacuum state;
and a sixth step: the testing system is started, the central hot plate unit, the upper cold plate (10) and the lower cold plate (3) are controlled to be heated to the testing temperature respectively, when the temperature sensor displays stably, and after the temperature uniformity of the central hot plate unit, the upper cold plate (10) and the lower cold plate (3) meets requirements, the heat conductivity coefficient of a tested sample is obtained through testing calculation, an N-type thermopile structure temperature difference testing method, an edge heating protection structure and a high-reflectivity radiation protection screen are adopted, the testing system meets a one-dimensional heat conduction model, the influence of environmental factors on a testing result can be effectively reduced, and the measuring precision is improved.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112305019A (en) * | 2020-10-26 | 2021-02-02 | 山东众盛工程检测有限公司 | Building outer wall heat preservation detection device |
| CN113376207A (en) * | 2021-06-07 | 2021-09-10 | 长安大学 | Over-and-under type coefficient of heat conductivity test instrument of constant temperature basin |
| CN114047223A (en) * | 2021-11-09 | 2022-02-15 | 中国航空工业集团公司北京长城计量测试技术研究所 | Two sample coefficient of heat conductivity measuring device of steady state method |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000329718A (en) * | 1999-05-20 | 2000-11-30 | Nippon Light Metal Co Ltd | Method and apparatus for measurement of thermal conductivity of foam sample |
| CN101738414A (en) * | 2009-12-22 | 2010-06-16 | 大连水产学院 | Device for testing low-temperature heat conduction rate of foam heat insulation material in loaded state |
| CN106814103A (en) * | 2016-12-17 | 2017-06-09 | 珠海彩珠实业有限公司 | A kind of device for measuring vacuum glass heat transfer coefficient |
| CN108663398A (en) * | 2017-03-31 | 2018-10-16 | 青岛理工大学 | Building glass thermal conductivity instrument |
-
2020
- 2020-03-30 CN CN202010233816.4A patent/CN111220652A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000329718A (en) * | 1999-05-20 | 2000-11-30 | Nippon Light Metal Co Ltd | Method and apparatus for measurement of thermal conductivity of foam sample |
| CN101738414A (en) * | 2009-12-22 | 2010-06-16 | 大连水产学院 | Device for testing low-temperature heat conduction rate of foam heat insulation material in loaded state |
| CN106814103A (en) * | 2016-12-17 | 2017-06-09 | 珠海彩珠实业有限公司 | A kind of device for measuring vacuum glass heat transfer coefficient |
| CN108663398A (en) * | 2017-03-31 | 2018-10-16 | 青岛理工大学 | Building glass thermal conductivity instrument |
Non-Patent Citations (4)
| Title |
|---|
| V.SCOARNEC: "A New Guarded Hot Plate Designed for Thermal-Conductivity Measurements at High Temperature", 《INTERNATIONAL JOURNAL OF THERMOPHYSICS》 * |
| 中华人民共和国国家质量监督检验检疫总局 等: "《中华人民共和国标准GB/T 10294-2008》", 31 December 2008, 中国标准出版社 * |
| 刘暐 等: "《传感器原理及应用技术》", 31 July 2019, 北京理工大学出版社 * |
| 李桂华 等: "《传感与检测技术项目式教程》", 31 January 2018, 北京理工大学出版社 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112305019A (en) * | 2020-10-26 | 2021-02-02 | 山东众盛工程检测有限公司 | Building outer wall heat preservation detection device |
| CN113376207A (en) * | 2021-06-07 | 2021-09-10 | 长安大学 | Over-and-under type coefficient of heat conductivity test instrument of constant temperature basin |
| CN114047223A (en) * | 2021-11-09 | 2022-02-15 | 中国航空工业集团公司北京长城计量测试技术研究所 | Two sample coefficient of heat conductivity measuring device of steady state method |
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