Development of thermal conductivity measurement system based on cryocooler for broad temperature range

Thermal conductivity at cryogenic temperature is one of the important parameters in aerospace, nuclear fusion and superconducting facility. Therefore, broad temperature and continuous measurement are necessary for accurate cryogenic thermal conductivity. Using a cryocooler, the system was designed and fabricated for measuring thermal conductivity from cryogenic to room temperature. To obtain the lowest temperature, the measurement system was optimised and the radiation shield was thermally connected to the second stage for intermediate cooling. The amounts of heat leak at first and second stages were predicted based on the calculation and compared with experimental results. Glass fibre reinforced plastic (GFRP) sample was cooled by a cryocooler and thermal conductivity was measured from 10 K to 100 K. The experimental results showed that the measurement values agreed well within 1% deviation comparing with literature values.