Abstract: In this paper, the effect of thermal resistance, heat leak and finite rate processes on the optimal performance of a irreversible quantum stirling refriger at or is studied. The maximum refrigeration rate and the optimal relation between the rate of refrigeration and the performance coefficient is derived. The results provides some theoretical guidance to the optimum design of a quantum refrigerator.

Key words: thermodynamics in finite time, harmonic oscillators, quantum ST refrigerator, quantum statistical mechanics