Design and development of porous regenerator for Stirling cryocooler using additive manufacturing

The performance of the Stirling cryocoolers essentially depends on the performance of the regenerator. The regenerator used in Stirling cycles has, essentially, having a high surface area and heat capacity leading to large heat transfers. Packed Metal wool, packed wire Mesh screen, randomly packed sphere, porous metal structure are some of the common types of regenerator matrix materials. Wire mesh based regenerators matrix material are common as it provides high heat transfer area with lower entropy generation rate. The paper study in detail the design and structural parameters of mesh type regenerators of Stirling cryocoolers. The work also involves the design, development and attempt to fabricate a prototype porous type Stirling Cryocooler regenerator with a porosity range of 69–71% using Direct Metal Laser Sintering (DMLS) techniques of additive manufacturing, which will enable to use it as a retrofit regenerator to the existing Stirling cycle based liquid nitrogen plants.