The performance of a single-stage closed-cycle miniature Joule-Thomson (JT) cryocooler operating with eight different neon-nitrogen-hydrocarbon mixtures is studied in this work. The cryocooler can provide refrigeration between 90 and 100 K and meet a cooling capacity requirement of 1 to 3 W \(\:{\text{d}}_{\text{h}}\) . Experimental studies are conducted using a miniature compressor with a stroke volume of \(\:\:1.4\:{\text{c}\text{m}}^{3}\) , and a coiled tubes-in-tube heat exchanger with an effectiveness greater than 98% is employed. A lowest temperature of 92 K and a maximum cooling capacity of. 3 W at 104 K are recorded. A sophisticated numerical model that includes all irreversibilities is developed to simulate a complete JT cryocooler. Parametric studies are conducted to understand the wide variation in cryocooler performance observed across different mixtures in the experimental studies. The numerical model helps select the optimal operating pressures for a given JT cryocooler’s hardware to achieve the maximum refrigeration potential of the mixture (maximum cooling capacity). The development of a single-stage mixed-refrigerant miniature JT cryocooler, its performance under applied heat load, and the results of parametric studies using the numerical model are presented.
