Dynamics of fibers in a wide microchannel

TL;DR

This study investigates how flexible fibers behave in a wide microchannel flow, revealing that proximity to walls, flexibility, and length influence their migration, deformation, and flow dynamics.

Contribution

It introduces a hydromultipole numerical approach to analyze fiber dynamics in microchannels, highlighting the effects of flexibility, length, and wall proximity.

Findings

Fibers closer to walls migrate faster towards the channel center.

More flexible and longer fibers deform more and migrate faster.

Flexibility and length affect fiber translation and deformation in flow.

Abstract

Dynamics of single flexible non-Brownian fibers, tumbling in a Poiseuille flow between two parallel solid plane walls, is studied with the use of the hydromultipole numerical code, based on the multipole expansion of the Stokes equations, corrected for lubrication. It is shown that for a wide range of the system parameters, the migration rate towards the middle plane of the channel increases for fibers, which are closer to a wall, or are more flexible (less stiff), or are longer. The faster motion towards the channel center is accompanied by a slower translation along the flow and a larger fiber deformation.