FREE-PISTON STIRLING CRYOCOOLERS.

Abstract

Stirling engines operate well as refrigerators. In the cryogenic range, they have become well established over the past 30 years in various military and commercial applications. Miniature cryocoolers are used extensively in infrared systems for night vision and missile guidance systems. Stirling engines are virtually unchallenged in this field and several thousand units are produced annually. It is the largest single application of Stirling engines for any purpose. Diverse other electronic and instrument applications for miniature or small Stirling cryocoolers exist or are foreseen for the near future. In larger sizes they are used in cryopumping, gas liquefaction, cryo-surgery, communications, high resolution optical systems. A description of integral free-piston Stirling cryocooler and split-Stirling cryocooler variants is presented, Large Stirling cryocoolers for gas liquefaction and refrigeration, as well as liquid-piston Stirling cryocoolers, are briefly discussed.