Investigation On Thermal Contact Resistance By Optical Measurement For Space Application

Thermal contact resistance(TCR) is becoming a popular problem in the field of spacecraft thermal control, it has a significant effect for spacecraft thermal control and pacecraft system design. At the same time, it is becoming an important factor that cannot be ignored in the science and engineering, such as electronics cooling, gas turbine and internal-combustion engine cooling, nuclear-reactor cooling, heat exchanger design.The investigation is supported by National Nature Science Foundation of China(51076013) and the Specialized Research Fund of the Doctoral Program of Higher Education(20040487039). We take the heat transfer problem of two solid material as a cut-in point and have a theoretical and experimental investigation of thermal contact resistance.The classical models of macro mechanism research on TCR in the aspect of the appearance of coarse interface, the distort of contact interface, thermal conductivity of contact point et al. have been discussed and compared. At the same time, there is a new way which is applied AMM and DMM to carry out micro mechanism research on TCR. Firstly,theoretical formula for achieving thermal diffusivity and TCR of solid specimen have been deduced.The cryogenic-vacuum photothermal experimental system is built, which the cool resource is G-M cryocooler. At the condition of cryogenic and vacuum, the thermal diffusivity of copper and aluminium, the TCR of Cu-Cu and Al-Al, have been measured. The experimental data has not reported in China yet. Photothermal measurement is a new approach for measuring cryogenic-vacuum TCR of solid for spacecraft application.From the Micro-Nanocryogenics view, there is a 3D low temperature micrometer(nanometer) interface layer at the two bulks contact interface, the microstructure of the interface layer is different from that of bulk material. The 3D interfacial layer is the main reason that leads to TCR. Therefore, it is of great importance both in application and theory to investigate the microstructure character of the interfacial layer, TCR and the heat transport across the interfacial layer from the point of views of Micro-Nanocryogenics.