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critical flow

critical flow The flow that occurs when the flow velocity in a river channel equals the wave velocity generated by a disturbance or obstruction. In this condition the Froude number (Fr) = 1. When the wave velocity exceeds the flow velocity (i.e. Fr is less than 1) waves can flow upstream, water can pond behind an obstruction, and the flow is said to be subcritical or tranquil. When Fr is greater than 1 waves cannot be generated upstream and the flow is said to be supercritical, rapid, or shooting. In this condition a standing wave is formed over obstructions in the river bed. In nature, supercritical flow is found only in rapids and waterfalls, but it is often created artificially by weirs and flumes, with the aim of measuring discharge.

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"critical flow." A Dictionary of Ecology. . Encyclopedia.com. 18 Dec. 2017 <http://www.encyclopedia.com>.

"critical flow." A Dictionary of Ecology. . Encyclopedia.com. (December 18, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/critical-flow-0

"critical flow." A Dictionary of Ecology. . Retrieved December 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/critical-flow-0

critical flow

critical flow Critical flow occurs when the flow velocity in a channel equals the wave velocity generated by a disturbance or obstruction. In this condition the Froude number (Fr) = 1. When the wave velocity exceeds the flow velocity (Fr is less than 1) waves can flow upstream, water can pond behind an obstruction, and the flow is said to be subcritical or tranquil. When Fr is greater than 1 waves cannot be generated upstream and the flow is said to be supercritical, rapid, or shooting. In this condition a standing wave is formed over obstructions in the river bed. In nature, supercritical flow is found only in rapids and waterfalls, but it is often created artificially by weirs and flumes with the aim of measuring discharge.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"critical flow." A Dictionary of Earth Sciences. . Encyclopedia.com. 18 Dec. 2017 <http://www.encyclopedia.com>.

"critical flow." A Dictionary of Earth Sciences. . Encyclopedia.com. (December 18, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/critical-flow

"critical flow." A Dictionary of Earth Sciences. . Retrieved December 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/critical-flow