Thermodynamic Analysis and Optimization of 80k Closed-Cycle Joule-Thompson Cryocooler with Gas Mixture

Abstract

Due to using a special mixture as the working substance of a Joule-Thompson cryocooler, the thermodynamic performance of the cryocooler can be greatly improved. In recent years, this kind of cryocooler has seen some new developments, using air-conditioning compressors, and consequently it can now be developed as a highly reliable and low-cost cryocooler. However, some fundamental problems are not well understood. One problem is how to avoid the solidification of high- boiling -temperature -point components. Another problem is how to choose the mixture components and optimize their compositions. In this paper, the thermodynamic aspects of these two problems are described. In addition, a more efficient mixed refrigerant is proposed for such Joule-Thompson cryocoolers.