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Scaling at the selective withdrawal transition

Itai Cohen·Sidney R. Nagel
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Abstract

In the selective withdrawal experiment fluid is withdrawn through a tube with its tip suspended a distance S above an unperturbed two-fluid interface. At low withdrawal rates, Q, the interface forms a steady state hump and only the upper fluid is withdrawn. When Q is increased (or S decreased), the interface undergoes a transition so that the lower fluid is entrained with the upper one, forming a thin steady-state spout. Near this discontinuous transition the hump curvature becomes very large and displays power-law scaling behavior. This scaling is used to show that steady-state profiles for humps at different flow rates and tube heights can all be scaled onto a single similarity profile.

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Itai Cohen, Sidney R. Nagel. 2002-01-16. Scaling at the selective withdrawal transition. https://doi.org/10.1103/physrevlett.88.074501

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