Progress Toward a Pulse‐tube/Reverse‐Brayton Hybrid Cryocooler

Future space‐based systems will require long‐life, active cryocoolers capable of achieving sub‐10 K load temperatures. Currently, the available cryocooler technology at these temperatures is too massive and inefficient. In many cases, reliability is low and vibration high. An innovative hybrid cryocooler is being developed to address these concerns. The cooler directly interfaces a recuperative, reverse‐Brayton, low‐temperature stage with a regenerative, pulse‐tube upper stage. This hybrid, multi‐stage cryocooler has the potential to be an efficient and compact device capable of meeting the cryogenic cooling needs of future space‐based systems. The concept of the hybrid cryocooler is reviewed briefly. Progress towards the development of the components within the hybrid system, including the pulse‐tube stage, rectifying interface, recuperative heat exchanger, and turbine, is described.