Collective behavior of particles in fluids
Paris, December 14-17, 2020

Leonid Berlyand (Penn State University)

From Active Swimmers in Newtonian Fluids to Living Liquid Crystals

We present a three-part review of our work on microswimmers over the last decade. In each part we begin from the experimental observations of our collaborators and proceed with PDE models and their rigorous analysis. First we discuss bacterial suspensions in Newtonian fluids. Here we describe PDE models that explained drastic reduction of the effective viscosity in dilute suspensions and emergence of the collective swimming in the semi-dilute suspensions. Next we discuss mimetic (artificial) microswimmers such as Janus self-propelled particles in Newtonian fluids leading to the concept of active ink in 3D printing and present rigorous analysis of kinetic models that explains the phenomena of bordertaxis and rheotaxis of these microswimmers. We conclude with an outline of the recent work in progress on bacteria swimming in anisotropic fluids (Living Liquid Crystals).

Several PSU PhD students and postdocs participated in the works which we present in this talk.

See slides and record.