Performance analysis of a micro-scaled quantum Stirling refrigeration cycle

Abstract

The cycle model of a general micro-scaled regenerative quantum refrigerator working with an ideal Bose or Fermi gas is established. The combined effects of quantum boundary and degeneracy on the performance of the cycle are investigated based on the thermodynamic properties of a confined ideal Bose or Fermi gas. The inherent regenerative losses of the cycle are analyzed and calculated. Expressions for several important performance parameters, such as the refrigeration load, work input, and coefficient of performance (COP), are derived under the cases of the gas degeneracy, weak gas degeneracy, high temperature limit, and thermodynamic limit. The curves of the refrigeration load and coefficient of performance versus the volume and surface area ratios of the cycle and the refrigeration load versus the coefficient of performance are represented. The effects of the size effect on the refrigeration load and coefficient of performance are discussed. The general performance characteristics of the cycle are revealed. It is found that both the refrigeration load and coefficient of performance of the micro-scaled quantum Stirling refrigeration cycle depend on the surface area of the cyclic system besides the temperature of the heat reservoirs, the volume of cyclic system, and other parameters, while those of the macro-scaled refrigerator are independent of the surface area of a cyclic system. The results obtained here are more general and significant than those in the current literature.