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Scaling dependence on the fluid viscosity ratio in the selective withdrawal transition

Itai Cohen
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Abstract

In the selective withdrawal experiment fluid is withdrawn through a tube with its tip suspended a distance S above a two-fluid interface. At sufficiently low withdrawal rates, Q, the interface forms a steady state hump and only the upper fluid is withdrawn.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 transition the hump curvature becomes very large and displays power-law scaling behavior. This scaling allows for steady-state hump profiles at different flow rates and tube heights to be scaled onto a single similarity profile. I show that the scaling behavior is independent of the viscosity ratio.

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Itai Cohen. 2002-01-16. Scaling dependence on the fluid viscosity ratio in the selective withdrawal transition. https://doi.org/10.1103/physreve.70.026302

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