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

Air pollutants in the boundary layer are well mixed. Sahana Ghosh, Quartz India, "India’s noxious emissions are messing up neighbours’ air, too," 8 Sep. 2019 The turbulence mixes moist air near the top of the cloud, pushing it up and out through an important boundary layer that caps stratocumulus clouds, while drawing dry air in from above. Natalie Wolchover, WIRED, "As the World Warms, Clouds Could Disappear—Catastrophically," 3 Mar. 2019 The mixture of the boundary layer is slightly cooler dry air and hot humid air which can cause intense storms. Hollie Silverman, CNN, "Severe weather brought flooding and a tornado to the Midwest. It also killed one person," 24 June 2019 That is, astronomers should be able to use the helioseismological measurements to calculate the depth of an important boundary layer in the sun where radiation gives way to convection. Quanta Magazine, "What Is the Sun Made Of and When Will It Die?," 5 July 2018 The forecast called for more on and off snow showers through the early afternoon and the focus was along the lakefront because of boundary layer convergence and the influence of a northeast wind off the lake,’’ Scott said. David Haugh,, "Snow job? Cubs postpone while White Sox play — and both teams made right call," 9 Apr. 2018 The ability to fly low in a hurricane reveals details about the engine of a hurricane: the boundary layer where warm evaporating water energizes the clouds above. Joe Pappalardo, Popular Mechanics, "NOAA's Revolutionary Hurricane-Hunting Drone Program Is Broke," 2 Oct. 2017 The boundary layer also makes them unsuited for desert climates, where the insulation puts them at risk of daytime overheating. Jason Daley, Smithsonian, "Why Are Some Leaves Massive and Others Minuscule?," 1 Sep. 2017

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.

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First Known Use of boundary layer

1921, in the meaning defined above

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Last Updated

20 Sep 2019

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The first known use of boundary layer was in 1921

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