Passive control of viscous flow via elastic snap-through

TL;DR

This paper presents a passive flow control device using an elastic arch that snaps between states to regulate viscous flow, with potential applications in microfluidic safety devices.

Contribution

The study introduces a novel elastic arch mechanism for passive flow regulation, combining experimental and theoretical analysis to determine transition conditions.

Findings

Arch snaps between constricting and unconstricting states depending on flux.

Hydraulic conductivity varies by up to an order of magnitude.

Device can be tuned for specific flow control applications.

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.