The Knudsen pump is a gas pump that utilizes no moving parts. Instead it uses the so-called thermal transpiration, the phenomenon that gas molecules drift from the cold end to the hot end of a narrow channel. 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, and even in satellites. It is named after Martin Knudsen a Danish physicist.
- Gas pump made of minerals has no moving parts, PhysOrg.com
- Knudsen Pump and Its Possibility of Application to Satellite Control, Kataoka, T. Tsutahara, M. Ogawa, K. Yamamoto, Y. Shoji, M. Sakai, Y., THEORETICAL AND APPLIED MECHANICS 2004, VOL 53, pages 155-162