Simulation and experimentation of a two-stage pulse tube cooler at 20 K

Abstract Small Stirling-type pulse tube cryocooler can be used to cool small optical devices due to the absence of moving elements in the cold head, long life, low vibration, and compactness. This paper reports a small two-stage Stirling-type pulse tube cryocooler that achieves a no-load minimum temperature of 20 K with 500 W of input electrical power and has 0.5 W@25 K cooling capacity. In addition to this, the effect of the second stage double-inlet on the P-U phase of the regenerator and the pulse tube is also simulated. The results show that the double-inlet has a significant effect on increasing the P-U phase difference between the inlet of the regenerator and the outlet of the pulse tube, which is much better than the effect of the length of inertial tube of this stage on the P-U phase.