Maximum attainable performance of pulse tube refrigerators Original Research Article

The nondimensional rate of refrigeration 〈Ḣ〉 of pulse tubes is shown to have a maximum attainable value of 1/4. The analysis is based on a linearized model in which the regenerator is thermally perfect and has negligible dead volume. The temporal variations are taken to be sinusoidal. At maximum 〈Ḣ〉, the coefficient of performance (COP) equals one-half the temperature ratio Tc/Th across the regenerator. In general, COP is a fraction between 0 and 1 of Tc/Th. The difference between the actual power provided at the driver side and the ideal power corresponding to COP=Tc/Th is dissipated in the regenerator. The resulting heat is transported to the warm end of the regenerator, where it is removed as part of the total heat flow rate.