{{short description|BranchType of hydraulicsliquid andflow fluidwithin mechanicsa conduit}}
'''Open-channel flow''', a branch ofIn [[hydraulicsfluid mechanics]] and [[fluid mechanicshydraulics]], '''open-channel flow''' is a type of [[liquid]] flow within a conduit or in channel with a [[free surface]], known as a [[Stream channel|channel]].<ref>{{Cite book|last=Chow|first=Ven Te|url=https://heidarpour.iut.ac.ir/sites/heidarpour.iut.ac.ir/files/u32/open-chow.pdf|title=Open-Channel Hydraulics|publisher=The Blackburn Press|year=2008|isbn=978-1932846188|___location=Caldwell, NJ}}</ref><ref>{{Cite book|last=Battjes|first=Jurjen A.|url=https://www.cambridge.org/core/books/unsteady-flow-in-open-channels/5CCE099F37BCC5AF4E67B35F15666E7B|title=Unsteady Flow in Open Channels|last2=Labeur|first2=Robert Jan|publisher=Cambridge University Press|year=2017|isbn=9781316576878|___location=Cambridge, UK}}</ref> The other type of flow within a conduit is [[pipe flow]]. These two types of flow are similar in many ways but differ in one important respect: the free surface. Openopen-channel flow has a [[free surface]], whereas pipe flow does not.
[[File:Arizona cap canal.jpg|alt=|thumb|[[Central Arizona Project]] channel.]]
