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Non-continuous Froude number scaling for the closure depth of a cylindrical cavity

Stephan Gekle·Arjan van der Bos·Raymond Bergmann·Devaraj van der Meer·Detlef Lohse
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Abstract

A long, smooth cylinder is dragged through a water surface to create a cavity with an initially cylindrical shape. This surface void then collapses due to the hydrostatic pressure, leading to a rapid and axisymmetric pinch-off in a single point. Surprisingly, the depth at which this pinch-off takes place does not follow the expected Froude$^{1/3}$ power-law. Instead, it displays two distinct scaling regimes separated by discrete jumps, both in experiment and in numerical simulations (employing a boundary integral code). We quantitatively explain the above behavior as a capillary waves effect. These waves are created when the top of the cylinder passes the water surface. Our work thus gives further evidence for the non-universality of the void collapse.

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Stephan Gekle, Arjan van der Bos, Raymond Bergmann, Devaraj van der Meer, Detlef Lohse. 2006-12-20. Non-continuous Froude number scaling for the closure depth of a cylindrical cavity. https://doi.org/10.1103/physrevlett.100.084502

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