Numerical and parametric analysis of Regenerator in SWaP-C miniature Stirling cryocooler for HOT IR technology

Abstract Miniature Stirling cryocoolers based on SWaP-C (Size, Weight, Power Consumption, and Cost) objectives for HOT IR technology have grown their importance in the industries of defense, aerospace, medical devices, and small-scale cryogenic systems. The regenerator is the most essential component of the miniature Stirling cryocooler. The effective geometrical and thermal design of the regenerator plays a major role in the overall cooling performance and compactness of a small-scale miniature Stirling cryocooler based on SWaP-C configuration. A numerical and parametric study of a cryogenic regenerator is conducted using REGEN3.3 and ANSYS Fluent, to determine the ideal values of regenerator operational and geometrical parameters that can either directly or indirectly contribute to the achievement of the SWaP-C objective with optimal performance for a small Stirling cryocooler. The results showed that with increased operating flow frequency, the regenerator’s COP increases while ineffectiveness decreases, potentially tolerating smaller regenerator length which can help in the overall compactness of the cryocooler. A longer regenerator improves thermal performance, but, on the other hand, it also causes a greater pressure drop and interferes with the desired SWaP-C goals. The analyses also revealed that the ideal operational and geometrical parameters of the regenerator with improved thermal performance can achieve enhanced SWaP-C characteristics of a miniature rotary Stirling cryocooler for the applications of HOT IR detectors.