Mesoscale simulations of polymer dynamics in microchannel flows

TL;DR

This study uses mesoscale simulations to explore how flexible polymers behave in microchannel flows, revealing two transport regimes and unique tumbling dynamics under confinement.

Contribution

It provides new insights into polymer dynamics in confined microchannel flows, highlighting the effects of confinement strength and flow on polymer behavior.

Findings

Two distinct transport regimes identified based on confinement strength.

Polymer length independence in strong confinement transport properties.

Non-periodic tumbling dynamics with sublinear flow dependence.

Abstract

The non-equilibrium structural and dynamical properties of flexible polymers confined in a square microchannel and exposed to a Poiseuille flow are investigated by mesoscale simulations. The chain length and the flow strength are systematically varied. Two transport regimes are identified, corresponding to weak and strong confinement. For strong confinement, the transport properties are independent of polymer length. The analysis of the long-time tumbling dynamics of short polymers yields non-periodic motion with a sublinear dependence on the flow strength. We find distinct differences for conformational as well as dynamical properties from results obtained for simple shear flow.