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arXiv · 1709.01694

Gaseous viscous peeling of linearly elastic substrates

Shai B. Elbaz·Hila Jacob·Amir D. Gat
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Abstract

We study pressure-driven propagation of gas into a micron-scale gap between two linearly elastic substrates. Applying the lubrication approximation, the flow-field is governed by the interaction between elasticity and viscosity, as well as weak rarefaction and low-Mach-compressibility, characteristic to gaseous microflows. Several physical limits allow simplification of the governing evolution equation and enable solution by self-similarity. These limits correspond to different time-scales and physical regimes which include compressiblity-elasticity-viscosity, compressiblity-viscosity and elasticity-viscosity dominant balances. For a prewetting layer thickness which is similar to the elastic deformation generated by the background pressure, a symmetry between compressibility and elasticity allows to obtain a self-similar solution which includes weak rarefaction effects. The results are validated by numerical solutions of the evolution equation

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Shai B. Elbaz, Hila Jacob, Amir D. Gat. 2017-09-06. Gaseous viscous peeling of linearly elastic substrates. https://arxiv.org/abs/1709.01694

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