Exergy Flow in Pulse Tube Refrigerators and Their Performance Evaluation Based on Exergy Analysis

Exergy flow in Orifice Pulse Tube Refrigerators (OPTR) is investigated. Input power to the compressor provides the source of exergy and the input exergy’s magnitude diminishes as working fluid passes through each component. The exergy destruction is due to the irreversibility of each component in the refrigerator. The only product of the system is the exergy associated with the refrigeration power. It is shown that for an ideal OPTR, where the orifice is the only source of irreversibility, the exergy destruction is equivalent to the refrigeration power resulting in a second law efficiency of (Th − Tc)/ Th for the system. A model for the effect of different system parameters on the irreversibility of the compressor, regenerator, and orifice is developed and exergy flow in the system is analyzed. A proper definition of the second law efficiency for each component is given and it is shown that exergy analysis is a powerful method for understanding the mechanism, performance evaluation, design, and optimizati...