Knudsen pump explained

The Knudsen pump also referred to as "thermal transpiration pump" or "Knudsen compressor" is a gas pump that utilizes no moving parts. Instead it uses thermal transpiration, the phenomenon that gas molecules drift from the hot end to the cold end of a narrow channel. Thus a hot vacuum chamber "transpires" into the cold chamber. This thermal transpiration flow is induced when the boundary walls of the pump have a temperature gradient. Because the pump is based simply on temperature differences and has no moving parts, it could provide reliable and precise control of gas flow for a variety of applications, such as gas-sensing breath analyzers, chemical weapons detectors,[1] and in satellite control.[2] It is named after Martin Knudsen, a Danish physicist.

Notes and References

  1. http://www.physorg.com/news147094299.html Gas pump made of minerals has no moving parts, PhysOrg.com
  2. Knudsen Pump and Its Possibility of Application to Satellite Control . Takeshi . Kataoa . Michihisa . Tsutahara . Kazuhiko . Ogawa . Yoshifumi . Yamamoto . Masakazu . Shoji . Yoshihide . Sakai . Theoretical and Applied Mechanics Japan . 2004 . 53 . 155 - 162 . 10.11345/nctam.53.155 . free .