Influence of quantum degeneracy on the performance of a gas Stirling engine cycle

Based on the state equation of an ideal quantum gas, the regenerative loss of aStirling engine cycle working with an ideal quantum gas is calculated. Thermalefficiency of the cycle is derived. Furthermore, under the condition of quantumdegeneracy, several special thermal efficiencies are discussed. Ratios of thermalefficiencies versus the temperature ratio and volume ratio of the cycle are made. Itis found that the thermal efficiency of the cycle not only depends on high and lowtemperatures but also on maximum and minimum volumes. In a classical gas state the thermal efficiency of the cycle is equal to that of the Carnot cycle. In an idealquantum gas state the thermal efficiency of the cycle is smaller than that of theCarnot cycle. This will be significant for deeper understanding of the gas Stirlingengine cycle.