Second-order Study of Micro-Stirling Cryocooler with Corrected Regenerator Temperature: Performance and Loss Analysis

Abstract

In this work, we present a second-order prediction of micro-Stirling Cryocooler with the dynamic loss factor incorporations in the overall analyses. Moreover, we also introduced the realistic distributions of the regenerator temperature into the second-order analysis. The second-order predictions differ significantly from the actual performances, primarily because of the inaccurate estimation of different thermodynamic, mechanical, and fluid dynamic losses. Thus, the impact of key input parameters such as average pressure, phase angle, and expansion temperature on these losses is explored extensively. Usually, the increase in average pressure improves heat transfer but also elevates pressure drops and mechanical friction, leading to higher fluid dynamics and mechanical losses. Similarly, the phase angle deviations from the optimal angle increase thermodynamic and mechanical losses, while the expansion temperature influences regenerator efficiency and thermal losses. A novel pythonbased second-order analyses package has been developed to investigate the overall performance of a single-stage Stirling cryocooler. The current approach predicts a lesser cooling effect (4% less) and COP (1.5% less) than the earlier findings, which brings the prediction closer to reality. Further, the variations in cooling effect and COP with different average pressure, phase angles (), and expansion temperatures (TE) are explored, and the optimal phase angle for maximum COP is found between 80𝑜 −90𝑜 .