阅读说明：本技术 一种辐射散热修正型航空背景材料的导热系数及界面热阻的稳态测试系统及方法 (Steady-state test system and method for heat conductivity coefficient and interface thermal resistance of radiation heat dissipation correction type aviation background material ) 是由 范利武 涂敬 冯飙 张宇鸿 俞自涛 于 2019-09-18 设计创作，主要内容包括：本发明公开了一种辐射散热修正型航空背景材料的导热系数和界面热阻的稳态测试系统及方法。所述装置由锗太阳能吸收板热源、辐射制冷板冷源、温度测试系统、数据采集系统等组成。热源和冷源均与一段圆柱形航空用铝合金材料相连,铝合金材料上侧向布置高精度温度传感器用于温度测试。冷热源及与之相连的导热体可在机械结构上保持同轴,冷侧固定,热侧可在轴向移动。铝合金导热体和试样放置部分外侧布置防辐射层。温度数据采集仪、温度传感器和连接导线外加防辐射层,采集仪由太阳能电池板供电。热源和辐射制冷板冷源能在太空环境中长期稳定工作,航空用铝合金材料的使用保证了系统能适应太空环境,防辐射层隔绝了测试系统在太空环境中的辐射散热。(The invention discloses a steady-state testing system and method for heat conductivity and interface thermal resistance of a radiation heat dissipation correction type aviation background material. The device comprises a germanium solar absorption plate heat source, a radiation refrigeration plate cold source, a temperature testing system, a data acquisition system and the like. The heat source and the cold source are both connected with a section of cylindrical aviation aluminum alloy material, and the high-precision temperature sensor is laterally arranged on the aluminum alloy material and used for temperature testing. The cold and heat sources and the heat conductor connected with the cold and heat sources can be kept coaxial on the mechanical structure, the cold side is fixed, and the hot side can move in the axial direction. And radiation protection layers are arranged on the outer sides of the aluminum alloy heat conductor and the sample placing part. The temperature data acquisition instrument, the temperature sensor and the connecting wire are additionally provided with a radiation-proof layer, and the acquisition instrument is powered by a solar cell panel. The heat source and the cold source of the radiation refrigeration plate can stably work in the space environment for a long time, the use of the aluminum alloy material for aviation ensures that the system can adapt to the space environment, and the radiation layer isolates the radiation heat dissipation of the test system in the space environment.)

1. A steady-state test system for the thermal conductivity and the interface thermal resistance of a radiation heat dissipation correction type aviation background material is characterized by comprising a germanium solar absorption plate heat source (1), a hot side aluminum alloy heat flow meter (2), a radiation protection layer (3), a cold side aluminum alloy heat flow meter (5), a radiation refrigeration plate cold source (6), a solar cell (7), a data acquisition instrument (8) and a temperature sensor (9); a germanium solar absorption plate heat source (1) is in contact connection with a hot-side heat flow meter (2), and a radiation refrigeration plate cold source (6) is in contact connection with a cold-side heat flow meter (5); the hot side aluminum alloy heat flow meter (2) and the cold side aluminum alloy heat flow meter (5) are coaxial in structure and are arranged oppositely, the germanium solar absorption plate heat source (1) and the hot side aluminum alloy heat flow meter (2) can integrally move along the axial direction, and the hot side heat flow meter (2) and the cold side heat flow meter (5) are respectively used for being tightly attached to two ends of a sample (4) to be tested; radiation protection layers (3) are arranged on the peripheries of the hot-side heat flow meter (2), the cold-side heat flow meter (5) and the sample (4); at least two temperature sensors (9) are arranged in the hot-side aluminum alloy heat flow meter (2), the cold-side aluminum alloy heat flow meter (5) and the sample (4) along the axial direction, and temperature data are acquired by a data acquisition instrument (8); the data acquisition instrument (8) is supplied by a solar cell (7).

2. The steady-state test system for the thermal conductivity and the interfacial thermal resistance of the radiation heat dissipation modified aviation background material according to claim 1, characterized in that the hot-side aluminum alloy heat flow meter (2), the cold-side aluminum alloy heat flow meter (5) and the test sample (4) are all cylindrical, and are coaxially arranged and have the same cross-sectional dimension.

3. The steady-state test system for the thermal conductivity and the interfacial thermal resistance of the radiation heat dissipation modified aviation background material according to claim 1, characterized in that two temperature sensors (9) are arranged in the hot-side aluminum alloy heat flow meter (2), the cold-side aluminum alloy heat flow meter (5) and the test sample (4) along the axial direction.

4. The steady state test system for thermal conductivity and interfacial thermal resistance of radiation heat dissipation modified aviation background material as claimed in claim 1, wherein said radiation layer (3) is composed of two separable parts.

5. A steady state test method for the thermal conductivity of a radiation heat dissipation modified aviation background material of the test system according to claim 1, characterized in that:

opening the radiation protection layer (3), and moving the germanium solar absorption plate heat source (1) and the hot-side aluminum alloy heat flow meter (2) to a certain distance away from the cold source; placing a single-layer to-be-measured sample (4) which is processed into a cylinder shape and is provided with a temperature measuring point between a hot-side aluminum alloy heat flow meter (2) and a cold-side aluminum alloy heat flow meter (5), moving a germanium solar absorption plate heat source (1) and the hot-side aluminum alloy heat flow meter (2) to a direction close to a cold source to be in mutual contact with the sample (4), and closing an anti-radiation layer (3); after the temperature distribution of the system is stable, recording the temperature data acquired by the data acquisition instrument (8) and measured by the temperature sensor (9); the data is processed to calculate the thermal conductivity of the sample.

6. A steady-state testing method for the interfacial thermal resistance of a radiation heat dissipation modified aviation background material of the testing system according to claim 1, characterized in that:

opening the radiation protection layer (3), and moving the germanium solar absorption plate heat source (1) and the hot-side aluminum alloy heat flow meter (2) to a certain distance away from the cold source; two layers of cylindrical samples (4) to be tested, which are provided with temperature measuring points, are tightly attached and placed between a hot-side aluminum alloy heat flow meter (2) and a cold-side aluminum alloy heat flow meter (5), a germanium solar absorption plate heat source (1) and the hot-side aluminum alloy heat flow meter (2) are moved to the direction close to a cold source to be in contact with the samples (4), and an anti-radiation layer (3) is closed; after the temperature distribution of the system is stable, recording the temperature data acquired by the data acquisition instrument (8) and measured by the temperature sensor (9); processing the data allows the interfacial thermal resistance between the samples to be calculated.

Technical Field

The invention relates to the field of steady-state testing of thermophysical properties of materials in a space environment, in particular to a steady-state testing system and a steady-state testing method capable of meeting the requirements of thermal conductivity and interface thermal resistance of the materials in the space environment.

Background

With the rapid development of aerospace technology, the activities of human beings in outer space are increasing. The human beings can not move in outer space without necessary space equipment and a system consisting of various equipment. These devices and systems are in a high vacuum, microgravity environment in space and require thermal control and management to ensure their proper operation. The mutual contact of various solid materials exists between cold sources and heat sources of the equipment, and the thermal resistance network of the equipment consists of the body thermal resistance of each material and the interface thermal resistance between adjacent materials. Therefore, for completely understanding the heat dissipation condition in the aerospace equipment and carrying out effective heat control and heat management, the heat conductivity coefficient of the aerospace material in the space environment and the interface thermal resistance between the materials are important parameters, and the method has important significance for the research of the aerospace material.

At present, the thermal conductivity and the interface thermal resistance are mainly obtained by means of testing, wherein the result accuracy of a steady-state testing method is concerned more. However, the thermal performance of the aviation material is mostly tested and calculated in a ground simulation environment, and the test of the thermal conductivity coefficient and the interface thermal resistance of the material in a space environment is difficult to realize. The test on the thermal conductivity coefficient and the interface thermal resistance of the aviation material in the space environment is researched, and the method has important significance for further exploring the universe for human beings.

Disclosure of Invention

The invention aims to overcome the defects in the existing research and provides a steady-state testing system and method for the thermal conductivity and the interface thermal resistance of a radiation heat dissipation correction type aviation background material. The basic principle of the test system is that the heat conductivity coefficient and the interface thermal resistance are measured by a steady state method, and adaptability change is made according to the difference between the space environment and the ground laboratory environment. The germanium solar absorption plate is used as a heat source of the test system, the radiation refrigeration plate is used as a cold source of the test system, and the germanium solar absorption plate and the radiation refrigeration plate work together to provide stable temperature difference for the test system. In order to respond to the characteristics of large temperature change (-200 ℃ -), microgravity and vacuum of the space environment, an aviation aluminum alloy material with excellent mechanical function, corrosion resistance and heat conductivity is adopted as a heat conductor between a cold source and a sample to be measured and a heat flow meter. In the space environment, heat radiation is the only heat radiation mode, and the circumferential heat radiation of the test part of the isolated steady-state test system can be realized by additionally arranging the radiation protection plate on the test part. The sample to be measured is placed between the aluminum alloys at the two sides of the cold and heat source, and one-dimensional temperature distribution can be obtained in the sample after the sample is stabilized. High-precision thermal resistors are arranged in the aluminum alloy heating flow meter and the sample, so that the internal temperature distribution conditions of the aluminum alloy heating flow meter and the sample can be obtained, and the heat conductivity coefficient of the sample and the thermal resistance of a contact interface between two layers of samples can be obtained through subsequent calculation.

The technical scheme of the invention is as follows:

the invention discloses a steady-state testing system and method for heat conductivity and interface thermal resistance of a radiation heat dissipation correction type aviation background material. The test system consists of a heat source, a cold source, a temperature test system, a data acquisition system and the like. The heat source is a solar energy absorption plate, and can stably work in the space environment. The cold source is a radiation refrigeration plate, and provides stable temperature lower than a constant value of the ambient temperature in the space environment. The heat source and the cold source are both connected with a section of cylindrical aviation aluminum alloy material, and a high-precision temperature sensor is arranged on the aluminum alloy material in the lateral direction and used as a heat flow meter. The material to be measured is also processed into a cylinder with the same diameter as the aluminum alloy heat conductor, temperature measuring points are arranged in the lateral direction, and temperature data are collected by a data collector. The cold and heat sources and the heat flow meter connected with the cold and heat sources are kept coaxial on the mechanical structure, the cold side is fixed in position, and the hot side can move a certain distance in the axial direction and is used for testing samples with different thicknesses. The radiation protection layer is arranged on the outer sides of the aluminum alloy heat conductor and the sample placing part, and the radiation protection layer is composed of two separable parts and can axially move along the direction close to the cold side. The radiation protection layer is additionally arranged on the data acquisition instrument, the temperature sensor and the connecting wire, and the data acquisition instrument is powered by the solar cell panel.

The steady state test system for the thermal conductivity and the interface thermal resistance of the radiation heat dissipation correction type aviation background material mainly comprises the following operation steps:

s1: opening the radiation protection layer, and moving the heat source and the heat conductor at the hot side for a certain distance in the direction away from the cold source;

s2: placing a sample to be tested between the two heat conductors, moving the heat source and the heat conductor at the side of the hot side to the direction close to the cold source to be contacted with the sample, and closing the radiation-proof layer;

s3: after the temperature distribution of the system is stable, recording the temperature data on the data acquisition instrument;

s4: according to the Fourier law, the heat flux density q in the heat conductor is as follows:

the heat flux density q in the cold-side and hot-side heat conductors can be calculated₁And q is₂Taking the average value:

the one-dimensional steady-state heat conduction heat flux density between the heat source and the cold source can be obtained. Wherein λ is_AlIs the heat conductivity coefficient, delta T, of aluminum alloy material_AlIs the temperature difference, delta x, of the adjacent temperature measuring points of the aluminum alloy heat conductor_AlThe distance between adjacent temperature measuring points of the aluminum alloy heat conductor is adopted;

s5: according to Fourier's law, the thermal conductivity of the sample to be measured is lambda_samComprises the following steps:

wherein, Delta T_samIs the temperature difference, delta x, between adjacent temperature measuring points of the sample to be measured_samThe distance between adjacent temperature measuring points of the sample to be measured is calculated;

s6: when two stacked samples are placed for testing, the temperature T of the sample at the hot side of the contact interface can be extrapolated according to the axial one-dimensional temperature distribution in the sample to be tested after the sample is stable_hAnd cold side sample temperature T_cThermal contact resistance R_cComprises the following steps:

compared with the prior art, the invention has the following beneficial effects:

(1) the difference between the space environment and the common laboratory environment is considered, the germanium solar absorption plate is used as a heat source, the radiation refrigeration plate is used as a cold source, and the cold and heat sources of the test system can stably work in the space;

(2) the characteristics of large temperature change, high vacuum and microgravity of the space environment are considered, and an aluminum alloy material for aviation is adopted as a partial material of a heat flow meter of the test system;

(3) the design of the radiation protection layer isolates the only radiation mode in the space environment, and the one-dimensional steady-state heat conduction between the cold and heat sources of the test system is ensured;

(4) the test system can obtain the thermal conductivity coefficient and the thermal resistance of the contact interface of the tested material in the space environment.

Drawings

Fig. 1 is a schematic structural diagram of a steady-state test system for the thermal conductivity and the interface thermal resistance of a radiation heat dissipation modified aviation background material.

FIG. 2 is a schematic diagram showing the temperature distribution of the titanium alloy used as the test material in the example.

In the drawings, the list of components is as follows:

1: a germanium solar absorber plate heat source; 2, a hot side aluminum alloy heat flow meter;

3: a radiation protective layer; 4: a sample;

5: a cold side aluminum alloy heat flow meter; 6: a radiation refrigeration plate cold source;

7: a solar cell; 8: a data acquisition instrument;

9: a temperature sensor.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

As shown in fig. 1, the steady-state test system for the thermal conductivity and the interface thermal resistance of the radiation heat dissipation modified aviation background material comprises a germanium solar absorption plate heat source 1, a hot-side aluminum alloy heat flow meter 2, a radiation protection layer 3, a cold-side aluminum alloy heat flow meter 5, a radiation refrigeration plate cold source 6, a solar cell 7, a data acquisition instrument 8 and a temperature sensor 9. The hot side aluminum alloy heat conductor 2 and the cold side aluminum alloy heat conductor 5 are coaxial in structure, and the germanium solar absorption plate heat source 1 and the hot side aluminum alloy heat flow meter 2 can axially move along the axial direction. Germanium solar panel heat source 1 and radiation refrigeration board cold source 6 work jointly, form temperature gradient between hot side aluminum alloy heat flow meter 2, cold side aluminum alloy heat flow meter 5 and sample 4, the circumference heat dissipation of cylindric heat conductor and sample has been isolated to the layer 3 of protecting against radiation, and after the system heat transfer is stable, form one-dimensional steady state heat transfer between the cold and hot source. And temperature sensors 9 are laterally arranged on the hot-side aluminum alloy heat flow meter 2, the cold-side aluminum alloy heat flow meter 5 and the sample 4, and temperature data are acquired by a data acquisition instrument 8. The data acquisition instrument 8 is supplied by a solar cell 7.

Fig. 2 is a temperature distribution condition simulation result after a system test part is in a stable state under the conditions that the temperature of a germanium solar absorption plate heat source 1 is 400K and the temperature of a radiation refrigeration plate cold source 6 is 300K by taking titanium alloy as a test material. The results show that the temperatures in the hot-side aluminum alloy heat flow meter 2, the sample and the cold-side aluminum alloy heat flow meter 5 are distributed in one dimension, and the requirements of the test system in the invention are met.

The working process of the invention is as follows:

s1: opening the radiation protection layer 3, and moving the germanium solar absorption plate heat source 1 and the hot-side aluminum alloy heat flow meter 2 for a certain distance in the direction away from the cold source;

s2: placing a single-layer test sample 4 to be tested between a side aluminum alloy heat flow meter 2 and a cold side aluminum alloy heat flow meter 5, moving a germanium solar absorption plate heat source 1 and the hot side aluminum alloy heat flow meter 2 to a direction close to a cold source to be in contact with the sample 4, and closing an anti-radiation layer 3;

s3: after the temperature distribution of the system is stable, recording the temperature data acquired by the data acquisition instrument 8 and measured by the temperature sensor 9; the thermal conductivity λ of the sample can be calculated from the equations (1) to (3)_sam；

S4: repeating S1 and S2, placing two layers of samples 4 to be tested on the side aluminum alloy heat flow meter 2 and the cold side aluminum alloy heat flow meter 5After the temperature distribution of the system is stable, recording the temperature data acquired by the data acquisition instrument 8 and measured by the temperature sensor 9; the interfacial thermal resistance R between samples can be calculated from the formula (4)_c。

Those skilled in the art will appreciate that the drawings are only schematic illustrations of one preferred embodiment, and the above embodiment numbers are merely for description and do not represent the merits of the embodiments. The above embodiments are only preferred embodiments of the present invention, but the implementation manner of the present invention is not limited by the above embodiments, and any other modifications, substitutions, combinations, simplifications, improvements, etc. within the spirit and principle of the present invention are included in the protection scope of the present invention.