Status and development trends of space mechanical refrigeration system at liquid helium temperature

On the basis of an overall introduction of mission objectives and cryogenics system performance requirements of the launched and developing cryogenic detectors at liquid helium temperature,this work analyzed the design methods and working performance of space oriented mechanical cryogenic technologies at liquid helium temperature,and also predicted the future trends of technical development.Space mechanical cryogenic technologies at liquid helium temperature mainly adopt linear compressor to drive pre-cooled 4He and 3He J-T throttling refrigeration technology,but for Stirling cryocoolers,sorption cryocoolers and high-frequency pulse tube cryocoolers which provide pre-cooling,further improvement of refrigeration efficiency is the key to realize the high efficiency of the entire machine.