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arXiv · 1708.05846

Passive control of viscous flow via elastic snap-through

Michael Gomez·Derek E. Moulton·Dominic Vella
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Abstract

We demonstrate the passive control of viscous flow in a channel by using an elastic arch embedded in the flow. Depending on the fluid flux, the arch may `snap' between two states --- constricting and unconstricting --- that differ in hydraulic conductivity by up to an order of magnitude. We use a combination of experiments at a macroscopic scale and theory to study the constricting and unconstricting states, and determine the critical flux required to transition between them. We show that such a device may be precisely tuned for use in a range of applications, and in particular has potential as a passive microfluidic fuse to prevent excessive fluxes in rigid-walled channels.

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Michael Gomez, Derek E. Moulton, Dominic Vella. 2017-10-28. Passive control of viscous flow via elastic snap-through. https://doi.org/10.1103/physrevlett.119.144502

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