Year: 2025
Type: article
Abstract: Adding swimming bacteria to a liquid causes its effective shear viscosity to decrease, eventually reaching a regime of zero viscosity. We examined whether this property leads to viscous fingerlike displacement fronts like those observed when a less viscous fluid displaces a more viscous liquid. Our study revealed that this system exhibits more complex dynamic characteristics than the classical Saffman-Taylor instability. We discovered that this instability occurs when the bacterial volume fraction exceeds a critical value and the imposed shear rate is below critical value, for which the viscosity of the suspension is zero.
Source: Physical Review Letters
Authors: Akash Ganesh, Carine Douarche, Harold Auradou
Institution: Université Paris-Saclay
Language: English
Topic: Micro and Nano Robotics
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4408815788