Experimental and dynamic simulation study of the Joule-Thomson cryocooler working at liquid hydrogen temperature

With advantages of long-life time, low level vibration and continuous refrigeration, precooling Joule-Thomson cryocooler (PJTC) working at liquid hydrogen temperature has the potential to be applied to liquid hydrogen storage system in space. For the large-cooling-power PJTC working at liquid hydrogen temperature, its dynamic response characteristic to heat load has a great importance on liquid hydrogen storage system, especially in aerospace applications. In order to study dynamic characteristics of PJTC working at liquid hydrogen temperature, an experimental setup for an open-cycle PJTC is built and its dynamic model is established by MATLAB software. Cool-down process and temperature variation characteristic with a heat load of 10.19 W are simulated and verified with experimental results. Meanwhile, the effect of precooling power on the performance of JT cryocooler is analyzed. It is found that if the precooling power is lower than 50% of the original precooling power, the recovery time of JT cryocooler will increase significantly.