boundary layer


Definition of boundary layer

: a region of fluid (such as air) moving relative to a nearby surface (such as that of an airplane wing) that is slowed by the viscosity of the fluid and its adhesion to the surface

Examples of boundary layer in a Sentence

Recent Examples on the Web Two slots appear in the floor ahead of each of the belts, controlling the boundary layer that would otherwise confuse the results. Jonathan M. Gitlin, Ars Technica, 21 Mar. 2022 For aeroacoustic testing the rolling road is covered, and arrays of microphones set up just outside of the boundary layer. Jonathan M. Gitlin, Ars Technica, 21 Mar. 2022 In the case of airplanes, there’s a fluid boundary layer, a thin layer of air that covers any surface. Manasee Wagh, Popular Mechanics, 11 Mar. 2022 The project planned to study the Mohorovičić discontinuity, an important boundary layer between Earth's crust and mantle situated at an average depth of 49,000 feet (15,000 meters) beneath the continents. David Bressan, Forbes, 22 May 2021 The dimples produce a thin, turbulent boundary layer of air that hugs the ball's surface, decreasing the size of wake at the back of the ball. Jeff Harper,, 11 Mar. 2021 Her specialty was the field of boundary layer effects on aerospace vehicle configurations at supersonic speeds. Julia Musto, Fox News, 27 Feb. 2021 Scientists explain the increasing evening heat by pointing to the section of the atmosphere called the boundary layer, which sits just above the ground. Jane Braxton Little, Scientific American, 27 Oct. 2020 That smoke starts off in the eddies of what atmospheric scientists call the boundary layer. Matt Simon, Wired, 31 Aug. 2020 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'boundary layer.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of boundary layer

1921, in the meaning defined above

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Time Traveler for boundary layer

Time Traveler

The first known use of boundary layer was in 1921

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Dictionary Entries Near boundary layer

boundary condition

boundary layer

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Statistics for boundary layer

Last Updated

19 May 2022

Cite this Entry

“Boundary layer.” Dictionary, Merriam-Webster, Accessed 29 May. 2022.

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