Effect of thermal and load cycle on thermal contact conductance across dissimilar joints at cryogenic temperature.pdfVIP

Applied Thermal Engineering 111 (2017) 1622–1628 Contents lists available at ScienceDirect Applied Thermal Engineering journal homepage: /locate/apthermeng Effect of thermal and load cycle on thermal contact conductance across dissimilar joints at cryogenic temperature Reji Joseph a,?, Jophy Peter a, S. Sunil Kumar a, N. Asok Kumar b a Liquid Propulsion Systems Centre, I.S.R.O., Thiruvananthapuram, Kerala 695547, India b Government Engineering College, Painavu, Idukki, Kerala 685603, India article info Article history: Received 31 March 2016 Revised 29 June 2016 Accepted 1 July 2016 Available online 2 July 2016 Keywords: Thermal contact conductance Cryogenic Load cycle Thermal cycle Dissimilar joint Hysteresis abstract Thermal Contact Conductance (TCC) at low temperature is of keen interest to researchers in the ?elds of aerospace, superconductivity, high speed semiconductor devices, cryogenic interfaces, etc. Change in thermal contact conductance at low temperature is associated with different factors like differential contraction, radial deformation of asperities and improved mechanical properties. When the joints undergo thermal, load or combined thermal and load cycles, changes in thermal contact conductance and heat ?ow across the joint are expected. In this work, experimental investigation of dissimilar metallic joints with temperature and load cycles was taken up. Joints formed by titanium alloy, stainless steel and aluminium alloy were considered for the study. Variation in thermal contact conductance across different joints with thermal and load cycles were investigated. The hysteresis associated with thermal contact conductance after load and temperature cycling was evaluated. The hysteresis effects are more for aluminium alloy joints which is known to have low hardness and high conductivity. ó 2016 Elsevier Ltd. All rights reserved. 1. Introduction Pressed joints are used in many cryogenic applications like aerospace joints, supports for cryogenic storage