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A viscous compressible model of soap film flow and its equivalence with the Navier-Stokes equations

Petri Fast
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Abstract

We present a quasi-two dimensional model of flowing soap films that bears striking similarity to the compressible Navier-Stokes equations. The variation in soap film thickness that is commonly used for flow visualization in experiments is analogous to density variations in the Navier-Stokes equations. When the soap film flow velocity is comparable to the Marangoni elastic wave velocity we recover the compressible Navier-Stokes equations and the soap film behaves like a two-dimensional isothermal viscous gas.

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Petri Fast. 2005-11-20. A viscous compressible model of soap film flow and its equivalence with the Navier-Stokes equations. https://arxiv.org/abs/physics/0511175

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