
Development of Dual flow JT Cooler
A Dewar is a vacuum encapsulation, used for packaging cooled-IR Detectors, which need to be operated at cryogenic temperatures of about 80 to 90K. The Dewar basically insulates the detector from atmospheric heat so that it can be easily cooled to the desired cryogenic temperature and thereafter can be maintained at that temperature, so long as the detector is operational. Normally for an on-board missile application, a Joule Thomson (JT) cooler is used for this purpose, as it is quite compact, offers minimum weight (10 -15 grams), have no moving parts and offers a very quick cool-down time of the order of about 7 to 20 seconds.