Kozyreff, G. and Howell, P. D. (2004) The instability of a viscous sheet floating on an air cushion. Journal of Fluid Mechanics . (Submitted)
The dynamics of a thin sheet of viscous liquid levitating on an air cushion is studied. Experimentally, it is observed that, after an initial settling stage, a local disturbance grows, eventually leading to the sheet blowing up like a viscous balloon. We derive a dynamical model for the levitating sheet and propose a mechanism for the onset of the instability. This instability is driven by the local drainage of the sheet due to a growing disturbance on its lower surface and is moderated by surface tension, the bending stiffness of the sheet and advection in the air layer. The balance between these effects determines the most unstable wavelength and this is illustrated by some numerical simulations.
|Subjects:||D - G > Fluid mechanics|
|Research Groups:||Oxford Centre for Industrial and Applied Mathematics|
|Deposited By:||Peter Howell|
|Deposited On:||09 Sep 2004|
|Last Modified:||20 Jul 2009 14:18|
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