Device for accurately measuring heat conductivity coefficient of metal
By using a constant temperature steam bath in the thermal conductivity measurement instrument to insulate the thermal conductivity measurement instrument, an insulating layer is formed to isolate the sample from the external environment, and the problem of low thermal conductivity measurement accuracy in the prior art is solved, and a higher precision measurement result is achieved.
Patent Information
- Application Number
- CN202421010080.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-10
- Publication Date
- 2025-02-28
- Estimated Expiration
- 2034-05-10
AI Technical Summary
In the prior art, the accuracy of the thermal conductivity measurement instrument is low and difficult to improve, mainly due to the difficulty in correcting the error caused by energy loss during the measurement process.
A device including an upper unit and a lower unit is designed to insulate heat using a constant temperature steam bath, steam is passed through the first to fourth chambers, forming an insulating layer, isolating the sample from the external environment, and reducing environmental interference.
Through the isolation of the thermal insulation layer, the accuracy of thermal conductivity measurement is significantly improved, measurement errors are reduced, and measurement results are provided with higher accuracy.
Smart Images
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Abstract
Description
Technical Field
[0001] The utility model relates to the field of thermal conductivity measuring instruments, in particular to a device for accurately measuring the thermal conductivity of metals. Background Art
[0002] Thermal conductivity is a physical property of materials. Accurately measuring the thermal conductivity of metal materials can deepen the application of materials in different industries.
[0003] In a physical laboratory, the thermal conductivity of a material can be measured by an instrument. However, during the measurement process, part of the energy will be lost to the experimental environment through heat conduction and heat convection, resulting in a large error in the determination of the thermal conductivity of the material sample. The parameters of the experimental environment cannot be controlled, resulting in the inability to effectively correct such experimental results. Therefore, in the prior art, the accuracy of thermal conductivity measurement instruments is relatively limited and difficult to improve.
[0004] It is not difficult to see that the existing technology still has certain defects. Utility Model Content
[0005] The technical problem to be solved by the utility model is to provide a device for accurately measuring the thermal conductivity of metals, which improves the measuring accuracy by performing heat insulation through a constant temperature steam bath.
[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:
[0007] A device for accurately measuring the thermal conductivity of metals, comprising an upper unit and a lower unit that can be opened and closed, and a constant temperature steam bath;
[0008] The upper unit is provided with two first cavities and a second cavity arranged up and down, the inlets of the first cavity and the second cavity are connected to the constant temperature steam bath, and the outlets of the first cavity and the second cavity flow back to the constant temperature steam bath through the reflux pipe; a thermocouple for detecting temperature is provided at the bottom of the upper unit;
[0009] The lower unit is provided with two third cavities and a fourth cavity arranged up and down, the inlets of the third cavity and the fourth cavity are connected to the constant temperature steam bath, and the outlets of the third cavity and the fourth cavity are refluxed to the constant temperature steam bath through a reflux pipe; a test cavity for accommodating a metal sample to be tested is provided on the top of the lower unit, directly opposite to the thermocouple of the upper unit, the top of the test cavity is open and a copper sheet for heat conduction is provided on the bottom, and a heater is provided under the copper sheet; a thermocouple for detecting temperature is provided on the lower surface of the test cavity.
[0010] Furthermore, the number of thermocouples provided on the upper unit and the number of thermocouples provided on the lower unit are both two.
[0011] Furthermore, the widths of the first cavity, the second cavity, the third cavity and the fourth cavity are equal to the width of the test cavity.
[0012] Furthermore, the upper unit and the lower unit are made of polymer materials.
[0013] Furthermore, a valve for controlling the switch is provided at the outlet of the constant temperature steam bath.
[0014] The utility model provides a device for accurately measuring the thermal conductivity of metal, which has the following advantages:
[0015] During the measurement process, steam is introduced into the first to fourth cavities, and the constant temperature characteristic of steam is utilized to isolate the sample in the instrument from the external environment, thereby reducing environmental interference and obtaining a thermal conductivity coefficient with higher accuracy. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the embodiments of the utility model 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 utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0017] Figure 1 The utility model provides an overall structural diagram of a device for accurately measuring the thermal conductivity of metal.
[0018] Figure 2 Schematic diagram of the internal structure of the upper unit and the lower unit.
[0019] Description of reference numerals:
[0020] 1. Upper unit 2. Lower unit
[0021] 3. Constant temperature steam bath 4. Valve
[0022] 5. First cavity 6. Second cavity
[0023] 7. The third cavity 8. The fourth cavity
[0024] 9. Thermocouple 10. Test chamber
[0025] 11. Copper sheet 12. Heater DETAILED DESCRIPTION
[0026] In order to make the purpose, technical scheme and advantages of the embodiment of the utility model clearer, the technical scheme in the embodiment of the utility model will be clearly and completely described below in combination with the embodiment of the utility model and the accompanying drawings. It should be noted that the described embodiment is only a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.
[0027] Embodiment 1
[0028] See also Figure 1 to Figure 2 , the embodiment of the utility model provides a device for accurately measuring the thermal conductivity of metal, comprising an upper unit 1 and a lower unit 2 which can be opened and closed to each other, and a constant temperature steam bath 3;
[0029] The upper unit 1 is provided with two first cavities 5 and second cavities 6 arranged up and down, the inlets of the first cavities 5 and the second cavities 6 are connected to the constant temperature steam bath 3, and the outlets of the first cavities 5 and the second cavities 6 flow back to the constant temperature steam bath 3 through the reflux pipe; a thermocouple 9 for detecting temperature is provided at the bottom of the upper unit 1;
[0030] The lower unit 2 is provided with two third cavities 7 and fourth cavities 8 arranged up and down, the inlets of the third cavity 7 and the fourth cavity 8 are connected to the constant temperature steam bath 3, and the outlets of the third cavity 7 and the fourth cavity 8 are refluxed to the constant temperature steam bath 3 through the reflux pipe; the top of the lower unit 2 is provided with a test cavity 10 for accommodating the metal sample to be tested, which is directly opposite to the thermocouple 9 of the upper unit 1. The top of the test cavity 10 is open and the bottom is provided with a copper sheet 11 for heat conduction, and a heater 12 is provided under the copper sheet 11; the lower surface of the test cavity 10 is provided with a thermocouple 9 for detecting temperature.
[0031] Before testing, the sample metal is cut into sheets matching the test cavity 10, such as a 10mm*10mm metal sheet with a thickness of 1mm, and placed in the test cavity 10. Then the upper unit 1 and the lower unit 2 are closed so that the upper and lower surfaces of the sample metal are pressed tightly, and the thermocouples 9 on the upper unit 1 and the lower unit 2 are in close contact with the sample metal.
[0032] The measurement was performed at least 3 times to calibrate the measurement data.
[0033] Each time the measurement is performed, the initial temperature T1 of the sample metal is first measured; then the heater 12 is powered on for heating, the current I and voltage V of the heater 12 are adjusted and recorded, and at the same time, the temperature of the thermocouples 9 of the upper unit 1 and the lower unit 2 is measured and the average value T2 of the temperature is calculated. The cross-sectional area of the test cavity 10 is A. Therefore, the thermal conductivity of the sample metal can be calculated according to the following formula:
[0034]
[0035] In this process, the physical properties of steam are applied. Under certain circumstances, the boiling point of the medium is determined, so the temperature of the steam is a stable value. For example, under a standard atmospheric pressure, the boiling point of water is a stable 100°C. Therefore, the steam in the first to fourth cavities 8 can form an insulating layer to isolate the test cavity 10 from the laboratory environment. Among them, a double-layer cavity insulation structure is adopted. The first cavity 5 blocks the second cavity 6, stabilizes the temperature of the second cavity 6, and thus makes the test cavity 10 unaffected by the outside world. Similarly, the fourth cavity 8 blocks the third cavity 7, thereby stabilizing the test cavity 10.
[0036] It should be noted that the steam medium does not necessarily have to be water vapor. Any medium with stable physical and chemical properties can be used as the steam medium in this device.
[0037] As an improvement, the number of thermocouples 9 provided on the upper unit 1 and the lower unit 2 is two. Equipping the upper and lower surfaces with two thermocouples 9 can avoid measurement errors and more accurately measure the temperature of the sample metal. When calculating the average value T2, the average value of the four thermocouples 9 is taken.
[0038] Preferably, the widths of the first cavity 5 , the second cavity 6 , the third cavity 7 and the fourth cavity 8 are equal to the width of the test cavity 10 , so as to match the sample metal.
[0039] As a further improvement, the upper unit 1 and the lower unit 2 are made of polymer materials, so as to reduce heat loss during the measurement process and avoid affecting the measurement results.
[0040] Preferably, a valve 4 for controlling the switch is provided at the outlet of the constant temperature steam bath 3 , so as to control the steam entering the constant temperature steam bath 3 .
[0041] The utility model provides a device for accurately measuring the thermal conductivity of metals, which utilizes the physical property of stable steam temperature and designs the first to fourth cavities 8 to pass steam as an insulation layer. Thus, the measured parameters are protected from the influence of the external environment, thereby measuring the thermal conductivity of the sample metal with higher accuracy. The device has a simple structure and high practicality.
[0042] The above-mentioned embodiments only express several implementation methods of the utility model, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent of the utility model. It should be pointed out that, for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, and these all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.
Claims
1. A device for accurately measuring the thermal conductivity of metals, characterized in that: It includes an upper unit and a lower unit that can be opened and closed, and a constant temperature steam bath; The upper unit is provided with two first cavities and a second cavity arranged up and down, the inlets of the first cavity and the second cavity are connected to the constant temperature steam bath, and the outlets of the first cavity and the second cavity flow back to the constant temperature steam bath through the reflux pipe; a thermocouple for detecting temperature is provided at the bottom of the upper unit; The lower unit is provided with two third cavities and a fourth cavity arranged up and down, the inlets of the third cavity and the fourth cavity are connected to the constant temperature steam bath, and the outlets of the third cavity and the fourth cavity are refluxed to the constant temperature steam bath through a reflux pipe; a test cavity for accommodating a metal sample to be tested is provided on the top of the lower unit, directly opposite to the thermocouple of the upper unit, the top of the test cavity is open and a copper sheet for heat conduction is provided on the bottom, and a heater is provided under the copper sheet; a thermocouple for detecting temperature is provided on the lower surface of the test cavity.
2. The device for accurately measuring thermal conductivity of metal according to claim 1, characterized in that: The number of thermocouples arranged on the upper unit and the number of thermocouples arranged on the lower unit are both two.
3. The device for accurately measuring thermal conductivity of metal according to claim 1, characterized in that: The widths of the first cavity, the second cavity, the third cavity and the fourth cavity are equal to the width of the test cavity.
4. The device for accurately measuring thermal conductivity of metal according to claim 1, characterized in that: The upper unit and the lower unit are made of polymer materials.
5. The device for accurately measuring thermal conductivity of metal according to claim 1, characterized in that: A valve for controlling the switch is arranged at the outlet of the constant temperature steam bath.