Passive Control of Viscous Flow via Elastic Snap-Through
Michael Gomez1, Derek E Moulton1, Dominic Vella1
1Mathematical Institute, Andrew Wiles Building, University of Oxford, Woodstock Road, Oxford OX2 6GG, United Kingdom.
Physical Review Letters
|October 21, 2017
Summary
An elastic arch passively controls viscous flow by snapping between constricting and unconstricting states. This tunable device offers potential as a microfluidic fuse for flow regulation.
Area of Science:
- Fluid dynamics
- Soft matter physics
- Microfluidics
Background:
- Controlling fluid flow is crucial in various scientific and engineering applications.
- Passive flow control methods offer advantages in simplicity and energy efficiency.
- Elastic instabilities in fluid-structure interactions are not fully understood.
Purpose of the Study:
- To demonstrate passive flow control using an embedded elastic arch.
- To investigate the bistability and tunable hydraulic conductivity of the arch.
- To explore the potential of this system as a passive microfluidic fuse.
Main Methods:
- Macroscopic scale experiments were conducted to observe flow behavior.
- Theoretical analysis was employed to understand the arch's mechanics.
- The critical fluid flux for state transitions was determined.
Main Results:
- The elastic arch exhibited two distinct states: constricting and unconstricting.
- Hydraulic conductivity differed by an order of magnitude between states.
- A critical fluid flux was identified for transitioning between states.
Conclusions:
- The elastic arch provides a tunable mechanism for passive viscous flow control.
- The system demonstrates potential as a reliable microfluidic fuse.
- This approach offers a novel method for regulating fluid flux in channels.
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