An assessment of the state of cryocooler technology for space applications

A survey is made which identifies more than 30 long life coolers for space applications covering a wide variety of thermodynamic cycles and configuration types. These coolers range in capacities from a few milliwatts to over 10 W at temperatures from 10 K to over 120 K and include single and multi-stage designs. The primary objectives of this study were to provide a hardware summary and performance comparison for potential space cryocooler users and to serve as an aid to the Air Force in determining future cryocooler development. The study identifies several existing flight qualified coolers and at least 12 programs which are likely to provide flight qualified units for cooling in the range of 10 to 150 K before the turn of the century. The survey presents an overview and status of the maturity of the various cryocoolers and performance comparisons are made at 35 K, 60 K, and 100 K.