Theoretical study on an innovative ejector enhanced Joule-Thomson cycle

This paper describes an innovative ejector enhanced Joule-Thomson cycle for low-temperature refrigerators. Since an ejector is introduced into the cycle, the cycle performance is profoundly affected by the pressure lift ratio and entrainment ratio of the ejector. As a case study, the performance characteristic of the novel cycle refrigerator using the non-azeotropic refrigerant mixture R14/R23 with the molar fraction of 0.6/0.4 is theoretically investigated in detail. The theoretical results show that in a typical refrigeration temperature range from -65°C to -95°C, the novel cycle refrigerator has 24.4%-41.5% improvement in coefficient of performance and 60%-220% enhancement in refrigeration capacity when compared to a basic Joule-Thomson cycle low-temperature refrigerator. This achieves a significant advantage as the use of the novel cycle is applied to low-temperature refrigerators for the medical and commercial applications.