Editing Laminar flow (section)

==Examples==
[[Image:Laminar flow.gif|thumb|right|In the case of a moving plate in a liquid, it is found that there is a layer (lamina) that moves with the plate, and a layer of stationary liquid next to any stationary plate.]]

A common application of laminar flow is in the smooth flow of a viscous liquid through a tube or pipe. In that case, the velocity of flow varies from zero at the walls to a maximum along the cross-sectional centre of the vessel. The flow profile of laminar flow in a tube can be calculated by dividing the flow into thin cylindrical elements and applying the viscous force to them.<ref>{{cite web
 |url         = http://hyperphysics.phy-astr.gsu.edu/hbase/pfric.html
 |title       = Laminar Flow
 |last        = Nave
 |first       = R.
 |year        = 2005
 |work        = HyperPhysics
 |publisher   = Georgia State University
 |access-date  = 23 November 2010
 |url-status     = live
 |archive-url  = https://web.archive.org/web/20110219090625/http://hyperphysics.phy-astr.gsu.edu/hbase/pfric.html
 |archive-date = 19 February 2011
}}
</ref>

Another example is the flow of air over an aircraft [[wing]]. The [[boundary layer]] is a very thin sheet of air lying over the surface of the wing (and all other surfaces of the aircraft). Because air has [[viscosity]], this layer of air tends to adhere to the wing. As the wing moves forward through the air, the boundary layer at first flows smoothly over the streamlined shape of the [[airfoil]]. Here, the flow is laminar and the boundary layer is a laminar layer. [[Ludwig Prandtl|Prandtl]] applied the concept of the laminar boundary layer to airfoils in 1904.<ref>{{cite book
 |title=A History of Aerodynamics and Its Impact on Flying Machines
 |last=Anderson
 |first=J. D.
 |year=1997
 |publisher=Cambridge University Press
 |isbn=0-521-66955-3
 |url=https://books.google.com/books?isbn=0521669553
}}</ref><ref>{{cite book
 |title=Laminar flow analysis
 |last=Rogers
 |first=D. F.
 |year=1992
 |publisher=Cambridge University Press
 |isbn=0-521-41152-1
 |url=https://books.google.com/books?isbn=0521411521
}}</ref>

An everyday example is the slow, smooth and optically transparent flow of shallow water over a smooth barrier.<ref>{{cite web |author=((sovereign578)) |title=Laminar Flow in Nature |url=https://www.youtube.com/watch?v=uaqKFeqRLik |website=YouTube |date=5 November 2016 |access-date=17 December 2019 |language=en}}</ref>

When water leaves a [[faucet|tap]] without an aerator with little force, it first exhibits laminar flow, but as acceleration by the force of gravity immediately sets in, the Reynolds number of the flow increases with speed, and the laminar flow of the water downstream from the tap can transition to turbulent flow. Optical transparency is then reduced or lost entirely.