Difference between revisions of "Knudsen Number"
From ExoDictionary
(No difference)
| |
Latest revision as of 17:00, 30 April 2007
This definition page has been automatically generated. You can help ExoDictionary by expanding, updating, or correcting it. |
| This autostub has not yet had its initial copyediting proof and may contain significant formatting and even factual errors. You can improve Exodictionary by cleaning up the page markup and verifying that the definition is correct and then removing this tag. |
| This autostub has not yet had its initial categorization proof and may be categorized incorrectly. You can improve Exodictionary by removing inappropriate categories and then removing this tag. |
Knudsen Number
</dt>
A number used to describe the flow of a low density gas, equal to the
ratio λ/l where λ is the mean free path of the gas molecule and l
is a characteristic length, such as boundary layer thickness, or apparatus
dimension.
</dd>
The Knudsen number is used most commonly to define the extend to which
the gas behaves like a collection of independent particles (free-molecule
regime, Knudsen number much larger than unity), or like a viscous fluid
(continuous regime, Knudsen number much smaller than unity). Intermediate
regimes are termed transition region, and slip flow
region. See rarefied
gas dynamics, note. [[/a>|/a>
]]
References
This article is based on NASA's Dictionary of Technical Terms for Aerospace Use
