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Shark skin effect in creeping films

M. Scholle·N. Aksel
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Abstract

If a body in a stream is provided with small ridges aligned in the local flow direction, a remarkable drag reduction can be reached under turbulent flow conditions. This surprising phenomenon is called the 'shark skin effect'. We demonstrate, that a reduction of resistance can also be reached in creeping flows if the ridges are aligned perpendicular to the flow direction. We especially consider in gravity-driven film flows the effect of the bottom topography on the mean transport velocity.

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M. Scholle, N. Aksel. 2006-05-26. Shark skin effect in creeping films. https://arxiv.org/abs/physics/0605232

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