TABLE OF CONTENTS The use of stored cryogens has been the preferred method for cryogenic cooling of a wide variety of scientific payloads during the past 30 years. In the future, other programs will rely on the same basic low-temperature storage technologies to enable the long-term storage of fluids for space exploration and military weapons systems. Stored expendable cooling systems are available in a broad range of types and applications, including
stored high-pressure gases used in combination with Joule-Thomson (JT) expansion devices
cryogenic liquids stored in a number of different states, including normal two-phase liquid/vapor (subcritical), low-pressure liquid/vapor (densified), and high-pressure, low-temperature single-phase (supercritical) states
solid coolers in which various expendable coolants are stored in the frozen state
Stored high-pressure gas JT systems have been used for intermittent or short-term cooling of infrared (IR) detectors in air-, space-, and ground-based missile systems. Subcritical fluids such as low-pressure helium have been used to cool very-low-temperature (~ 1.4 K) sensors for astronomy missions. Storage of super-critical fluids (those operating at a higher pressure and in a single-phase state) has provided oxygen and nitrogen for atmosphere constituents in crewed space applications. Solid coolers provide several advantages over the liquid storage systems, including elimination of phase-separation issues, higher density and heat capacity, and the more stable temperature control required for many sensors.
Recently the concept of zero boil-off (ZBO) systems utilizing...
