Numerical simulations and experimental verifications of a three-stage gas-coupled 4.0 K Stirling-type pulse tube cryocooler.

Abstract

This paper conducts theoretical and experimental investigations on a three-stage gas-coupled Stirling-type pulse tube cryocooler (SPTC). A two-dimensional computational fluid dynamics (CFD) model is established in which the interactions between compressor and cold finger (CF) are analyzed and the distributions of PV power simulated as well. The effects of operating frequency and charge pressure on the performances of both compressor and CF are modeled in detail. Based on the above theoretical studies, a three-stage gas-coupled SPTC is then worked out and tested. The experimental results show that it reaches a no-load temperature of 4.5 K. The electric input power and the motor efficiency of the compressor are 320 W and 81.5%, respectively. When using He-3, the no-load temperature reduces further to 4.0 K. Finally, the SPTC prototype shows great potential for 4-10 K space applications due to its compact configuration, high reliability, low vibration and high cooling efficiency.