Measurements of interfacial thermal contact conductance between pressed alloys at low temperatures.pdfVIP

Cryogenics 80 (2016) 33–43 Contents lists available at ScienceDirect Cryogenics journal homepage: /locate/cryogenics Measurements of interfacial thermal contact conductance between pressed alloys at low temperatures Jiang Zheng a, Yanzhong Li a,b,?, Pengwei Chen a, Geyuan Yin a, Huaihua Luo a a School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an 710049, China b State Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong University, Xi’an 710049, China article info Article history: Received 13 June 2016 Received in revised form 8 September 2016 Accepted 8 September 2016 Available online 13 September 2016 Keywords: Thermal contact conductance Low temperature Load exponent Hardness abstract Interfacial thermal contact conductance is the primary factor limiting the heat transfer in many cryogenic engineering applications. This paper presents an experimental apparatus to measure interfacial thermal contact conductance between pressed alloys in a vacuum environment at low temperatures. The measurements of thermal contact conductance between pressed alloys are conducted by using the developed apparatus. The results show that the contact conductance increases with the decrease of surface roughness, the increase of interface temperature and contact pressure. The temperature dependence of thermal conductivity and mechanical properties is analyzed to explain the results. Thermal contact conductance of a pair of stainless steel specimens is obtained in the interface temperature range of 135–245 K and in the contact pressure range of 1–9 MPa. The results are regressed as a power function of temperature and load. Thermal conductance is also obtained between aluminums as well as between stainless steel and aluminum. The load exponents of the regressed relations for different contacts are compared. Existing theoretical models (the Cooper-Mikic-Yovanovich plastic model, the Mikic elastic model and the improved Kimura model) are reviewed and comp