Performance Characteristics of a Joule–Thomson Refrigeration System with Mixed Refrigerant Composition

Energy and Exergy Analysis of Cascade Mixed Refrigerant Joule–Thomson System with the Application of a Precooler

“…High-boiling refrigerants serve to condense through the cooling medium during initial operation and simultaneously determine the dew point at the set pressure. A higher dew point implies that at a constant temperature, the state points after the CHX shift further to the left, thereby reducing the compressor's suction and discharge temperatures [30]. Medium-boiling refrigerants are essential for sustaining continuous phase changes, while low-boiling refrigerants play a crucial role in establishing the target temperature and the saturation line.…”

“…A large enthalpy difference at a specific temperature implies that the amount of heat absorbed by the refrigerant (in both liquid and vapor phases) increases as it passes through the expansion valve until it reaches the compressor's suction point. To achieve a smooth temperature reduction in the internal heat exchanger from the fixed temperature at −20 • C (state point 7 in Figure 2) to the target cooling temperature, a consistently high enthalpy difference must be maintained due to the evaporation temperature of the HTC [30,31]. The selected refrigerants can be categorized into three groups: high-boiling refrigerants (R-134a, R-218, R-125), medium-boiling refrigerants (R-116, R-23), and lowboiling refrigerants (R-14, argon).…”