Space chamber | Stirling Cryogenics
Space simulation chambers
The temperature in outer space is around 3K, however depending on where you are in space (in relation to you position of the earth and sun) this varies. Temperature on the moon can fluctuate from 40K to 396K!!. Morever space can be considered as an almost perfect vacuum.
Organizations like NASA, ESA, Ford Aerospace and others building (parts of) spacecrafts, satellites etc. need to test their equipment and materials at those extreme temperature and vacuum conditions. Thanks to the low temperatures that can be obtained by using liquid nitrogen this is an optimum means to obtain space-like temperatures inexpensively. Parts, complete satellites or space crafts are tested in space simulation chambers or vacuum chambers. Depending on their use these chambers can vary from small (diameter < 0,5 meter) to very large (8 meters or more in diameter). Also they will vary in temperature and vacuum they can achieve.
Space simulation chambers are typically lined with panels at liquid nitrogen temperature (77-100K) to absorb radiation heat from the tested items. Cryogenic vacuum pumps mounted onto the chamber are used to create and maintain high vacuum capturing molecules either from degassing of materials used on the test object or through the intentional release of gases from the object (engine, thrusters etc.).
Smaller chambers may use liquid helium (4K) or gaseous helium (10-80K). The heat load on the shields can vary from a couple of watts to 100’s of kWs.
The reliquefaction system is of high (economic) value to the Georgia Institute of Technology. A technical paper about the system and its performance can be found here: Recirculating Liquid Nitrogen System for Operation of cryogenic pumps by Alexander W. Kieckhafer and Mitchell L. R. Walker
Stirling Cryogenics offers a whole range of products and services for use with space chambers:
GPC-1 & 4
These installations are equipped with a gaseous helium transfer system (CryoFan and heat exchanger). Cold helium gas (20-80K) is circulated from the cryocooler to the space chamber, through the thermal shroud and back to the cooler in a closed loop). Since the 1960’s Stirling has supplied numerous of these units to companies performing (aero)space simulations.
StirLIN liquid nitrogen plants
Liquefier plants are used for on site production for economics and/or to eliminate the need for logistic requirements with bulk supply (large storage tanks, piping, trucks, etc.).
SPC-1 & 4
Basic one and four cylinder cryogenerators to be used in custom build re-liquefication systems. Cold gaseous nitrogen returning from the space chamber is returned to the cryogenic plant where it is liquefied again.
All systems mentioned above can be designed and configured according customers' specific needs.
For use in applications as described the following Stirling Cryogenics products may be considered: