Design of a multi-layer insulation(MLI) measurement system with a G-M cryocooler

27th International Cryogenics Engineering Conference and International Cryogenic Materials Conference 2018

Li, X.^1^2 ; Xu, D.^1^2 ; Shen, F.Z.^1^2 ; Liu, H.M.^1 ; Li, L.F.^1^2

Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing

100190, China^1

University of Chinese Academy of Sciences, Beijing

100049, China^2

关键词: Aerospace propulsion system;    Boundary temperature;    Effective thermal conductivity;    Environment pressure;    Evaporation rate;    Measurement system;    Multi-layer insulation;    System structures;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/502/1/012075/pdf
DOI  :  10.1088/1757-899X/502/1/012075

来源: IOP

【 摘 要 】

Multi-layer insulation (MLI) is widely used in cryogenic systems such as Aerospace propulsion systems and various cryostats. The effective thermal conductivity of MLI used in lab is measured by typical systems using bath cryostat, which is only able to maintain boundary temperatures at critical point of cryogen. A liquid cryogen-free apparatus based on a two stage G-M cryocooler has been developed to measure the effective thermal conductivity of multi-layer insulation(MLI) materials at temperatures ranging from 20-300 K. Unlike traditional measurement systems utilizing evaporation rate of liquid cryogen, a calorimeter supported by a calibrated rod is installed in this system to determine the heat flow through the testing blanket. This design eliminates the error caused by variation of environment pressure to the measured evaporation rate, and meanwhile, simplifies the system structure.Published under licence by IOP Publishing Ltd.