Cryogenics

Channel:

all the knowledge of the universe PRINCIPIA

Subscribers:

1,920

Published on December 10, 2021 9:55:48 AM ● Video Link: https://www.youtube.com/watch?v=_kpoZZyHINE

Duration: 7:08

45 views

0

Cryogenics, by Wikipedia https://en.wikipedia.org/wiki?curid=7176 / CC BY SA 3.0

#Cryogenics
#Cooling_technology
#Industrial_gases
Liquid nitrogen This is a diagram of an infrared space telescope, that needs a cold mirror and instruments.
One instrument needs to be even colder, and it has a cryocooler.
The instrument is in region 1 and its cryocooler is in region 3 in a warmer region of the spacecraft.
（see MIRI （Mid-Infrared Instrument） or James Webb Space Telescope） A medium-sized dewar is being filled with liquid nitrogen by a larger cryogenic storage tank In physics, cryogenics is the production and behaviour of materials at very low temperatures.
The 13th IIR International Congress of Refrigeration （held in Washington DC in 1971） endorsed a universal definition of "cryogenics" and "cryogenic" by accepting a threshold of 120 K （or –153 °C） to distinguish these terms from the conventional refrigeration.
This is a logical dividing line, since the normal boiling points of the so-called permanent gases （such as helium, hydrogen, neon, nitrogen, oxygen, and normal air） lie below −120 °C while the Freon refrigerants, hydrocarbons,
and other common refrigerants have boiling points above −120 °C. The U.S. National Institute of Standards and Technology considers the field of cryogenics as that involving temperatures below −180 °C （93 K; −292 °F）.
Discovery of superconducting materials with critical temperatures significantly above the boiling point of liquid nitrogen has provided new interest in reliable, low cost methods of producing high temperature cryogenic refrigeration.
The term "high temperature cryogenic" describes temperatures ranging from above the boiling point of liquid nitrogen, −195.
79 °C （77.36 K; −320.42 °F）, up to −50 °C （223 K; −58 °F）.
Cryogenicists use the Kelvin or Rankine temperature scale, both of which measure from absolute zero, rather than more usual scales such as Celsius which
measures from the freezing point of water at sea level or Fahrenh...