Miniaturization of Thermoacoustic Expander for 50 mW Recuperative Coolers Run Below 40 K

The objective of this program is to demonstrate and miniaturize a new type of cryogenic expander, thermoacoustic expander (TAE), for space cryocoolers which provide the cooling power less than 50 mW and operate in the low temperature range between 40K and 10K for cooling SWIR, MWIR, and LWIR surveillance and interceptor systems. TAEs employ high energy acoustic waves generated with absolutely no mechanical moving parts at the cold expander to produce efficient cooling over a wide temperature range. The TAE can replace more conventional complex mechanical moving part turbines or piston expanders as well as Joule Thomson expanders. The novel expander is applicable to cooling multiple sensors or focal planes especially if they must be vibrationally decoupled from the host vehicle, and allowes for efficient integration of a low mass cold head with remote and/or numerous objects to be cooled. In phase I, a proof of concept unit will be designed, fabricated and tested.